# Specific 3D Printers, Scanners, & Hardware > Peachy Printer Forum >  Mount and Reservoir Discussion

## Toasterboy

Hey folks, with the Peachy printer hitting 1.0 and hopefully shipping soon, let's talk about reservoir, build area, and mounting options.

I'm planning to use straightwall industrial containers for my build area.  I have a place in my shop where I can mount the printer to a wood beam and the build area can sit on a shelf below it.  For the reservoir, my plan is a Costco milk jug or two.  Also planning to mask off the area with cardboard to shield against stray UV.  I'm also considering mounting the printer on a milk crate (can do both to have options).

I got several sizes of this for my build area:
http://www.globalindustrial.com/g/st...all-containers
Looking forward to trying the 24x22.5x14.5 one and printing some larger items. Has anybody tested printing larger items?

From the videos, looks like Rylan is using Montana jars.  I assume that straight vertical walls help make the z-level consistent (i.e. no variance due to container shape).  Montana jars seem to top out in size around 2.5 gallons.  Besides industrial crates, and Montana jars, what else works?  Containers with actual straight, vertical walls are uncommon as most things are designed with a taper for stacking. 

What are you all planning to use?

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## jontelling

I'm glad you've started this thread, I thought about it but felt I was spamming a little. 

For the build container I'm thinking a science lab beaker, they have straight sides and a very small curve at the bottom. 
Anything for the salt water container. 

As for the build area, it will be nice to know the projection degrees on the peachy, after all that will give you both the heigh to build width ratio. 

I'm looking to use the same sort of thing as used in the videos for the build base, maybe something with a tighter mess, but not too much more. 

Still unsure how I'm going to project it from UV light and build the peach support, maybe some orange plastic film around an cheap wooden frame.  :Smile:

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## rylangrayston

Hey Great Thread guys 
Ill just make a bunch of points

- if your dripping ( ie not using a pump hack or something) keep it SMALL and tall , like 2 litres, if you dont then prints take a long time or should i say a cubed time  :Smile: 
The smaller the printer the faster you print, the quicker you solve problems.
- The standard setup that we recommend you get working first uses 2 liter pop bottle for the bottom resivour 
- We plan to let you tell the software the top and bottom dimensions of your container so that it can solve 
- To block uv light we will make an orange plastic film available in our on line store, by the foot.
- put an old towl under your printer and surrounding aria, so little drops of salt water and resin don't make a mess. 

lets see what else can i say on this topic...
We will be making instructions for a standard setup, and while im totally all for the wild variety of ways people will customize there peachy printers, I really think
that everyone should start out by building a standard setup first! There is just so many things to learn because of how unconventional the peachy is. 
Once you get a standard peachy printer setup working in only takes a min to transfer the parts over to your awsome uniqe setup, and I guarantee the knowledge you gain
printing in a standard setup will save you lots of time. 

having said that here are some things to consider for your none standard setups. 

- the standard dripper can do about 2 liters per hour. 
- pic a container that is rigid enough that the side walls dont bow out as you fill it with water. 
- slightly tapered containers still work, we print in 1 litre yogourt containers all the time. ( the taper squashes the tops of your taller prints a bit, but maybe your just having fun and you dont care) 
- pick something clear so you can see the printing happen
- dont print in something that you might eat out of ever again ( because resin is really spicy in a chemically bad kind of way ) 
- What ever your setup be sure to post It in the forums!  that way we all learn together, and who knows maybe peachy printer will sponsor your project  :Smile:

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## Chayat

I'm interested to know what has been learnt about the base for a print. You seem to be using a bit of wire mesh has there been experiments with mesh size, orientation and the like?

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## rylangrayston

> I'm interested to know what has been learnt about the base for a print. You seem to be using a bit of wire mesh has there been experiments with mesh size, orientation and the like?


  basically any porous bump surface works great, we have printed on aluminum window screen and the 1/4 mesh you see in our recent videos. 
very early on ( befor the crowd funding ) i printed on the rocks you get for a fish tank.... i would just fill the bottom half of a jar with rocks and every print came out with about 10 pebbles attached.... it made starting the printer again a breeze. 

as for what dosent work 
flat smooth surfaces... in the crowd funding video some of our prints were done on the iner surface of an aluminum can that we cut open... you could blow those prints off there bases .. it was annoying but it looked smooth and didn't distract the eye from the action in the shot.

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## Toasterboy

How big of a build area have you actually tested?

What is the maximum deflection angle for the peachy like?  I'd like to get an idea of how high the printer needs to be mounted as related to desired build area dimensions.  (i.e. height above top of build area container). 

If it works (even if somewhat slowly) with the dripper for larger volumes (i.e. 2'x2'x2'), then it could make sense to look at ways to increase the fill rate of the build container (a pump hack, or whatever, to make the print times less painful).  Maybe something involving a pair of motorized ball valves and a continuously running small pump to facilitate "scaling up" the drips for larger containers. With an adjustable size holding reservoir between the valves (i.e. with a diaphragm or something like a syringe + stepper motor so it can be controlled, and with open air overflow so the holding tank always fills to the exact correct volume), it might be fully automated (just enter the build volume size in the software and it can solve for the correct settings), and provide extremely consistent Z on the scaled up "drips".

If the printer angle is narrow, it may make trying to print a lifesize canoe require an impractical mounting height though=) 

And with napkin math, at 2 liters per hour, something like the ~24"x22.5"x14.5" build area I suggested above would only take about 64 hours to fill  (if I calculated correctly), which isn't that much worse than print times I've heard of for other large build area printers.  Definitely would want to look at increasing the fill rate if I try to print at that size though... 

This thread is insightful.  You've been fantastically open about the details of this project and it's been fun watching as you have brought the Peachy to life... Thanks!

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## Toasterboy

I did some more napkin math.... if the pump/holding tank/ valve setup is calibrated to drop ~.35ML for each "drop", that would correspond to about 1 micron Z in a tank sized 24"x22.5"x14.5".   So...a modified syringe with the valves I described would work pretty well for that volume.  Seems like you could maintain extremely fast print speeds simply by scaling up the size of the "drops" in larger containers.  

So how wide  can we make the deflection angle on the printer?  It would be cool if it can be made wide enough to accommodate mounting the printer on the ceiling and then printing into a vat on the floor.... it could probably scale to printing car sized objects easily enough.

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## jontelling

> ....... then it could make sense to look at ways to increase the fill rate of the build container.........


I'm not sure this is the case, bigger build area, bigger build therefore more resin to cure, as with all lasers the power is limited this means the laser will take longer to cure each layer. Which means it needs to be kept slow.

If the current limiting factors on build speed are related to the moving the mirrors (slow and steady to avoid vibrations etc) then you can up the Z-axis speed. If the laser is the limiter then the z-axis will need to be kept just as slow.

I could be totally wrong though…

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## Toasterboy

I'm not suggesting scaling up the fill rate with small containers; only for large containers.  Keep the fill rate proportional to what works in small containers.  They used water drops in the design because they are consistent in volume and provided an extremely cheap , easy to sense z mechanism.

Rylan mentioned in another thread that they are working on a software modification to allow the laser to stay on continuously; right now it shuts off and pauses waiting for the z level to reach the desired level between layers.  That suggests that the z-level rate is a strong limiting factor.  It's also a good question what the deflection speed performance of the laser is.  The videos are sped up, but they seem to show the laser moving fast enough so as to appear to be a continuous line...   I would expect the surface dynamics (i.e. the interface between water, resin, and laser) to behave similarly to the small scale build reservoir;  I expect you would need to account for additional travel time on the laser for curing for larger objects, but that should essentially scale linearly with the surface trace path length.  It seems like the z-level rise rate is the larger limiting factor in a large container.  Using a calibrated valve system for z-filling essentially makes it digital, and with digital 2-way control, it could be software controlled rather than depending on sensing the drip rate.  It only makes sense with containers above some size threshold though, as it's harder to calibrate and deliver smaller water volumes approaching water drop size, making the drops a better choice for small containers.

Certainly you will use more resin on larger objects, although with hollow shells, that is still pretty economical.  

Perhaps this a is a feature that the Pro could explore.  I'm definitely going to play around with this concept though.  If only I had the printer in hand.  I missed the original Kickstarter window and ordered my Peachy through BackerKit. =)

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## Toasterboy

Aha, didn't know about peristaltic pumps.  One of those would work great and be much cheaper than I was thinking.

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## jontelling

> Aha, didn't know about peristaltic pumps.  One of those would work great and be much cheaper than I was thinking.


I may make a syringe pump one day  :Smile:

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## Toasterboy

Reading the peachy beta kit instructions, it looks like the calibration step is smart enough to scale the Z per "drip" based on the height provided. Is that correct? 

If so, and we replace the basic dripper with a peristaltic pump, it seems like the drip contact detection mechanism should still work about the same.  If  the volume of the pulses from the peristaltic pump is small enough that the z-level rise in the container per pulse is appropriate for the target layer height (i.e. operates at a similar scale to dripping in a small container does), I would think it would be OK.   Looks like I can get an appropriate 12V pump (one which pushes 20-100ml per minute) for about $10 plus power supply (I have a 12v dc controller for a train that should work for testing).  May be a very easy mod?

So....that still leaves the question of what the maximum deflection angles the printer can support are, so it doesn't have to be mounted 30' in the air to get larger build volumes.

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## jontelling

> Reading the peachy beta kit instructions, it looks like the calibration step is smart enough to scale the Z per "drip" based on the height provided. Is that correct? 
> 
> If so, and we replace the basic dripper with a peristaltic pump, it seems like the drip contact detection mechanism should still work about the same.  If  the volume of the pulses from the peristaltic pump is small enough that the z-level rise in the container per pulse is appropriate for the target layer height (i.e. operates at a similar scale to dripping in a small container does), I would think it would be OK.   Looks like I can get an appropriate 12V pump (one which pushes 20-100ml per minute) for about $10 plus power supply (I have a 12v dc controller for a train that should work for testing).  May be a very easy mod?
> 
> So....that still leaves the question of what the maximum deflection angles the printer can support are, so it doesn't have to be mounted 30' in the air to get larger build volumes.


From the other thread Rylan said the drips as the z-axis can be out by 5%, but a peristaltic pump is 1%. As you say the drip detector should be be the same so it should work great and better than a passive dripper.  :Smile: 

I can see speed printing becoming a thing,  :Smile:

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## rylangrayston

Hey Tosterboy
The peachy printer is very easy to modified and it was built with that in mind, including the way we write the software. 
You can definitely signal the drip detection pins with other things like photo interrupters or reed switches, what ever you like. 

As for deflection 
We typically print with deflections of up to 20 degrees ether side of zero.  ( so 40 deg total swingl) 
But even the peachys max deflection is very easy for you to change by changeing the spring force ( moving a few magnets) 
By lowering the spring force you can get the mirror to go a full 180 deg (not that the laser will hit the mirro at this point, but you cant do it. 

We have yet to Write a feature where you get N calibration points. ( Right now you just get 8.) 
and because higher deflections require dealing with many none linear we ares We plan to avoid them for the time being.

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## oninoshiko

hopefully the community will help with a lot of these kinds of mods and experiments once we start seeing more peachys out there!

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## Toasterboy

Awesome.  40 degrees of deflection is great.  With those angles, 10' of height (e.g. a ceiling mount) gives you 7.2' square of surface below the top of your build area, so this seems like it's already operating at a good scale for doing very large prints. 

How long does the laser need to cure each layer?   Say, if you are targeting 1 micron layers or so.  This is important for understanding how much acceleration of the dripping actually makes sense to attempt.  Does the software compensate (or need to compensate) for longer cure times at the larger outside angles ?

Oh, what is the interface for the 2-way digital communication?  Is it going to be possible to signal a drip command and/or other parameters? Would be sweet to digitally control the dripping.  I have also been thinking about using a used automotive fuel injector; they typically have open/close times in the neighborhood of 2ms, so an injector would provide excellent digitally controllable variable drip size and frequency, though it would also require a pump.

Thanks again for the great work on this printer project.  I can't wait to get my hands on one.

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## oninoshiko

> Awesome.  40 degrees of deflection is great.  With those angles, 10' of height (e.g. a ceiling mount) gives you 7.2' square of surface below the top of your build area, so this seems like it's already operating at a good scale for doing very large prints. 
> 
> How long does the laser need to cure each layer?   Say, if you are targeting 1 micron layers or so.  This is important for understanding how much acceleration of the dripping actually makes sense to attempt.  Does the software compensate (or need to compensate) for longer cure times at the larger outside angles ?
> 
> Oh, what is the interface for the 2-way digital communication?  Is it going to be possible to signal a drip command and/or other parameters? Would be sweet to digitally control the dripping.  I have also been thinking about using a used automotive fuel injector; they typically have open/close times in the neighborhood of 2ms, so an injector would provide excellent digitally controllable variable drip size and frequency, though it would also require a pump.
> 
> Thanks again for the great work on this printer project.  I can't wait to get my hands on one.


If memory serves, one of the project goals was to try and print a full-sized canoe, so large prints was always something that needed to be possible.

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## rylangrayston

> Awesome.  40 degrees of deflection is great.  With those angles, 10' of height (e.g. a ceiling mount) gives you 7.2' square of surface below the top of your build area, so this seems like it's already operating at a good scale for doing very large prints. 
> 
> How long does the laser need to cure each layer?   Say, if you are targeting 1 micron layers or so.  This is important for understanding how much acceleration of the dripping actually makes sense to attempt.  Does the software compensate (or need to compensate) for longer cure times at the larger outside angles ?
> 
> Oh, what is the interface for the 2-way digital communication?  Is it going to be possible to signal a drip command and/or other parameters? Would be sweet to digitally control the dripping.  I have also been thinking about using a used automotive fuel injector; they typically have open/close times in the neighborhood of 2ms, so an injector would provide excellent digitally controllable variable drip size and frequency, though it would also require a pump.
> 
> Thanks again for the great work on this printer project.  I can't wait to get my hands on one.



The software dose no yet do exposure compensation for the laser spot becoming elongated at higher deflections, but this is planed. 
Since the laser spot isnt round It draws like a calligraphy pen ( its a very suttle effect) but that hasnt been accounted for in exposure ether.

how long would it take to cure a 7.2 ft long layer (say were printing a 7.2 foot long wall)  from a celing mount....
The peachy printer software dosent use accelaration yet, instead we just go the speed at which we can turn a sharp corner and still have it look sharp.
Which is about 1 second per 40 degrees of deflection. But by the time we ship acceleration will very likely be working so the printer will be much faster than it is now.
ok so we know that we can go about 7.2 ft per second in this masive setup what is that in mm per second
7.2  * 12 * 25.4 = 2194 mm per second is the speed the laser spot would be travleing. 
To expose the resin at that speed we will need lots more laser power.
typicaly in a small printer we go at 100 mm/s  so now we need 22 times the laser power of a standard setup ( 2194 / 100)
I cant quote exactly how many mw a standard printer emits just yet. 

now here i need to be careful I dont want anyone to think that a normal peachy printer emits an extremely powerful laser beam, that can burn the flesh on your arm... 
We have put various measures in place limit the laser power to safer levels, so that you only need laser saftly glasses, and or a good enclosure around your printer, to be safe. 
We also dont want the diodes to burn out so we are shipping diodes that are over rated for the job, technically they could handle emitting 50 mw with no aperture and a heat sink. 
Which would be very dangerous to the eye! For liability reasons im sure its a bad idea for me to explain how to make the laser more powerful but I trust the community of expert hackers here has all the skills necessary to thwart our safety measures and get a printer to emit more laser power.
So I will just end with a warning, Lasers can be really dangerous, make sure your taking the necessary precautions, alwase where laser safety glasses, not just normal safely glasses and build a completely  enclosed printer, so that when others walk in to the room unexpectedly, they are safe too.


As for a hack to tell the peachy that you have just Put water in the printer.. There will be lots of ways to do this but here is one I did just yesterday it works like this :

paristaltic pump shaft > IR inturpt sensor > arduino( with debounce script) ----voltage divider----> peachy printer circuit  ----USB---> peachy printer software

Peachy circuit is 3.3 volt hence the voltage divider between it and the arduino and the 10k resistor between the peachy circuit and ground makes me feel safe if i happen to create a ground loop between it and the arduino. So when pin 13 goes high the peachy gets 2.5 volts, which is over the 1.8 volt on threshold for its 3 volt circuit. 

IMG_3793.jpg


and here is the debounce code for the arduino:



```
int ledPin = 13;
int sensorPin = 8;
int debounceTime = 1000 / 20 ;

void setup() {                
  pinMode(ledPin, OUTPUT); 
  
}

void loop() 
{
  
  if (digitalRead(sensorPin) == HIGH )
  {
  
    digitalWrite(ledPin, HIGH);   
    delay(debounceTime);
    
  }
   
  
  
  else if( digitalRead(sensorPin) == LOW ) 
  {
    
    digitalWrite(ledPin, LOW);
    delay(debounceTime);
  }
  
}
```

I love the injector + pump Idea , I dont know how injectors will like salt water but i know there are some injectors that put water into diesel engines ( making steam that makes extra power from the heat in the engine) 
I hope you will post all about some it day.

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## jontelling

Nice informative reply Rylan. But as always I have more questions.  :Smile: 

Do you plan (I'm sure you do) allow serial input to the peachy board? I ask as this would allow an arduino (are in my case as I had a bad habbit of blowing them an atmega chip) to bridge the gap between a PC (via wifi) or an SD card or even just tell the peachy that you added XXml to the build area of salt water.

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## Toasterboy

Yes, thanks for the great response. I'm really excited about the printer.

Are there any other I/O pins for output on the peachy board?  It sounds like there is a drip sensor pin on the board ; wondering if there's another pin for output besides USB, or if the expectation for this hardware version is that the Peachy software would signal other (separate) devices (like a drip assembly) through other I/O mechanisms on the computer.  

It seems like long term, the printer (or its successor) should have the capability to signal the zlevel rise directly rather than relying only on external passive decoupled drip + detection.  Since the travel path of the laser for each layer is variable, to get optimal print speed it would benefit from being controlled by signal rather than depending on an external sensed rate.  But I can certainly see where it makes sense to focus engineering on a whole list of other areas, like laser speed and accuracy, and variable laser focus and power output that need to be tackled first.  It might be a bit silly to build a super accurate, super fast Z level control mechanism to support larger build areas if the laser speed / power needed requires minutes to cure each layer. =)  Still, accurate, controlled z-level on smaller volume build areas is still useful and important.

>We have yet to Write a feature where you get N calibration points. ( Right now you just get 8.)
Can you comment on this further?  8 points for which calibration?  for Z or for XY?

I picked up a used 300cc fuel injector on Ebay for really cheap.  The math suggests that for the ~2'x2' container, @~40psi the injector should be held open about 80ms per pulse to get 0.33ML, the amount needed to raise 1 micron in this container. (roughly)  Assuming that salt water flows similarly to gasoline, and the used injector is in more or less good condition, and the thing is actually accurate.  That's a lot of assumptions.  Will need to experiment and see if it's in the ballpark.  

I also picked up a peristaltic pump.  It's a bit hard to tell from the specs what the pulse size will be.  Anyway, I can play with both ideas.  What size pump are you playing with above?

I'm not going to attempt to run anything bigger than 2'x2' for now.  That size is still manageable to build UV cage around for safety (not to mention it will be a while yet before you guys are ready to ship).  And anyway, even if the injector can do the z-level rise at ~12.5 pulses per second as the napkin math suggests, the laser speed has a long way to go before it can cure that many layers per second (if it's even possible to go that fast).

What is the layer height you are using on your test prints? With surface tension and other effects, how would you say the printer is performing with respect to z-layer height?

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## rylangrayston

> Nice informative reply Rylan. But as always I have more questions. 
> 
> Do you plan (I'm sure you do) allow serial input to the peachy board? I ask as this would allow an arduino (are in my case as I had a bad habbit of blowing them an atmega chip) to bridge the gap between a PC (via wifi) or an SD card or even just tell the peachy that you added XXml to the build area of salt water.


along these lines here is what we were thinking ( but have not done yet) 
use the extra IO pins to create ic2 and or SPI communication ports, so that an arduino can send and receive any message to the printer via the peachy circuit and so that 
the peachy circuit could posibly control things like LCD screen, button panel etc. 

What we do have working now is the peachy software sending commands thru a separate serial port, this is how we do our time lapses of prints an arduino is instructed to open the shutter while the laser drawing 1 layer.  We also have send codes to the arduino to turn the peristaltic pump on and off, or whatever else we want.

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## rylangrayston

> Yes, thanks for the great response. I'm really excited about the printer.
> 
> Are there any other I/O pins for output on the peachy board?  It sounds like there is a drip sensor pin on the board ; wondering if there's another pin for output besides USB, or if the expectation for this hardware version is that the Peachy software would signal other (separate) devices (like a drip assembly) through other I/O mechanisms on the computer.  
> 
> It seems like long term, the printer (or its successor) should have the capability to signal the zlevel rise directly rather than relying only on external passive decoupled drip + detection.  Since the travel path of the laser for each layer is variable, to get optimal print speed it would benefit from being controlled by signal rather than depending on an external sensed rate.  But I can certainly see where it makes sense to focus engineering on a whole list of other areas, like laser speed and accuracy, and variable laser focus and power output that need to be tackled first.  It might be a bit silly to build a super accurate, super fast Z level control mechanism to support larger build areas if the laser speed / power needed requires minutes to cure each layer. =)  Still, accurate, controlled z-level on smaller volume build areas is still useful and important.
> 
> >We have yet to Write a feature where you get N calibration points. ( Right now you just get 8.)
> Can you comment on this further?  8 points for which calibration?  for Z or for XY?
> 
> ...


There are about 8 extra io pins( i dont have the details memorized because we havent started using them yet) 

a more direct Z height will definitively get implemented something like a g code to the micro that says goto this height travleing at this speed. 

more on calibration.. 
We are working on a 3dmentional matrix of points that can be used to interpenetrate out all the non-linearities for all the places the laser can be in the build volume... but dam thats a wordy way to say it, and a year ago I wouldn't have understood what I just wrote.. so ill try to put it into an analogy too. This analogy by the way is actually how i prefer to think of it: 

say you had a clear cube of Jellow and inside this cube of jelow was a bright red capital letter T.
To get the Red T in the clear block of jellow you cast the T first, then placed flopy red T in a cube and then poured clear jellow around it. 
Great just one problem, The Upper Right tip of the T  is sagging down, but the upper left side is bent towards you and also bent up. 
What can you do to correct this. 
what if you had put iron balls in the upper right and upper left parts of the T.  Then you could use magnets pull on the balls just enugh to unwarp the 
Saggy T.  The balls would squish and warp the jellwo around them, Such that the T could become less saggy. 
Now what if you had 100 magic balls that you could move magicaly in the jellow, then you could really straighten out that saggy T to perfection. 

In this analogy above the magic balls are our calibration points. We get to magically move the balls because we have a mathematical representation ( a 3d matrix ) of the jello cube / build volume.  The atoms of jellow are akin to every resolution point in our build volume, just like the position of each atom in affected by the balls near to it, we interpolate the position of every resolution point so that our calibration points affect the resolution points near them. 

Currently we only have done the work to have 1 ball at each corner of the cube shaped build volume, so we only have 8 balls  and there only in the corners. 
  This means currently we can only remove linear artifacts, for example we can correct for things like the entire T leaning, but we cant yet unwarp a specific part of the T.  Some day we will do work to allow you to decide to have as many calibration points as you like, and when that day comes your printer could be much more accurate. 

hope that analogy made thing better not worse  :Smile: 

Glad to here of the progress on the injector pump idea already Toasterboy! 
lets see whats next.., pump size.. We have been making our own pumps so now its time for my napkin math
Today I was printing in a 6 in diamter cylinder, and there are 206 pump rotations per mm so ....
6* 2.54 = 15.24 cm diameter
15.24/ 2 = 7.62 cm radius
7.62 * 7.62 = 58.06
58.06 * 3.14 = 182.32mL
182.23/2000 pumps per cm = .091 mL per pump rotation 

The pump uses between 100 and 200 mA depending on speed which is controlled via votages between 3 and 20 volts. 

as for how its doing in the z resolution. I think there is a recent post where I explained this in some detail... ill see if i can find it...
EDIT: found the posts with details about z resolution, there on the 3rd page of update 51 thread.. here is a link
http://3dprintboard.com/showthread.p...Printer!/page3


Great questions everyone, Im happy to answer them now while the community is still small, someday there may be thousands of people joining and posting, and Ill be glad to have all the help I can get from those of you who are here now learning about the peachy printer in detail before anyone else  :Smile:

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## Toasterboy

Ok, Cool.
You might be able to play with the Mesh Deform Cage in Blender to rapidly zero in on the required deformation matrix.  i.e. model a concentric onion cube (with smaller cubes inside) like shape, print, measure, and play with the deformation in Blender .. seems like it wouldn't take too many prints and a caliper to get the deformation seed matrix close to correct.  Probably help the larger you can print the test object.

Cool.. so the sample prints are about 10 micron Z or so.

Your results with the peristaltic pump sound promising. =)  
Has anyone done any tests with vibrating the build area to overcome surface tension/meniscus?

I got the injector in the mail today, but I'm waiting for the pump still, so it will be a bit (and a trip to the hardware store for other bits) before I  can play with it further.

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## jontelling

> I got the injector in the mail today, but I'm waiting for the pump still, so it will be a bit (and a trip to the hardware store for other bits) before I  can play with it further.


Are you a beta tester or are you just doing a ad-hoc test of water levels before the V1.0 arrives? Please post pics etc, will be nice to see. 

You mentioned the meniscus, ive only thought about it a little, but was there a mention that it was an issue or are you thinking once you go to a super high Z resolution? heh you could have a rod moving up and down in the build fluid, as long as it doesn't fully emerge there shouldn't be any ripple. hehe i can see it now, a big pully and a rod attached.  :Smile:

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## rylangrayston

> Ok, Cool.
> 
> Has anyone done any tests with vibrating the build area to overcome surface tension/meniscus?
> 
> I got the injector in the mail today, but I'm waiting for the pump still, so it will be a bit (and a trip to the hardware store for other bits) before I  can play with it further.


Its alwase great to here of people taking actual actions like ordering parts for unique setups, this kind of thing really excites me! I second jontelling, post pics!

as for vibration, very early in the project I spent hours tapping the printer in different spots watching how vibration actualy helped in many situations ( such as when your using a higher powerd laser) I bough a bunch of cellphone vibrators, sealed them in hot glue and diped them into the resin while printing, but i didnt spend enugh time experimenting to really say anything other than there seems to be potential in this idea. My next step on this one would be to get big speaker to set the bottom tank on, and then make the speaker do a range of feq and wave forums over the course of a print to see what works. It been funny because usually I here people talking about how vibration will make the printer fail. I Think controlled vibration could improve things, and if the same vibration that improves surface tension also causes the mirros to shake, its prety easy to vibrate in between the drawing of each layer.  Oh ultasonic mixers are another thing to try ( if set to a low power, so they dont actually mix the resin and water)

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## Toasterboy

=)

I'm not a beta tester.  Would be fun though.. wish I had my hands on a Peachy. =)   The dripper assembly is decoupled from the actual printer, so it's quite feasible to experiment with the dripper without a printer.

I was thinking meniscus would be more of a problem the faster you go (i.e. more powerful laser) and the thinner the layers are, and the thinner the laser beam is.  If the printer ever gets "accelerated" to the point that it can do multiple layers per second for example. 

I'm missing a few parts still. Attaching a pic of what I have so far.

The question is really just whether the fuel injector will accurately/consistently dispense in a range appropriate for controlling z-level in a build vat (of variable size).  Since that's similar to what injectors are designed to do in an engine, chances are good that it will.  

The injector seems to fire just fine at 12volt 3 amps. (some of them need 6 amps)  I don't have specs on it so I'm not sure if it needs more.  Don't have a scope.  3 amps might not be enough to get the injector open as fast as it can go.

Initially I'll just program the arduino to dispense at a fixed rate and dispense into a measuring container with stopwatch.  If that works out to be in the ballpark over a good range, I'll probably add a display and buttons to make it adjustable without uploading new code to the arduino.

I'm thinking the peristaltic pump makes more sense for the Peachy at the speed it's currently operating at.  Something like this injector setup probably won't be needed unless the laser is beefed up and the Peachy can handle moving the laser much faster so it can cure multiple layers in a second.
arduino_injector_bench_small.jpg

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## rylangrayston

Intresting that you brought up layers per second 

so way back in this update we were doing some very small prints. they were esp small in the xy 
at a square collum that is 2mm x 2mm for example has a 2* 4 sides so a circumference of 8 mm
100 mm/s /8mm = 12.5 layers per second. 
so even the basic printer when given small jobs can do many layers per second.

you can see lots of examples of this fast printing here:



PS Thanks for posting that pic!

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## Toasterboy

Fantastic!  Yeah, I thought you had mentioned that early on.  Do you think that prints #76-78 might have gone better with a buzzer breaking the surface tension and an injector or pump providing really stable Z raise in synchronization with the laser?  The implication is that with a 1 or 2 watt laser (or focusing the 20mw one) the printer could go very fast indeed if the surface tension effects can be solved.

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## Toasterboy

Ok, so I programmed the arduino to fire the injector 20 times a second and hold it open 80 ms each pulse.   Wired up the pump, and connected the hydraulics with surgical tubing (and zip ties, after the hoses popped off the first time) =)   Using regular water for now.

Latex tubing expands in such a way that it provides approximately constant pressure, apparently.  (people use variations of it to power homemade cps supersoakers).

#1 Wow, the clicking from the relay I bought is annoying... it's a lot louder than the injector, which is quiet.

#2 It basically works.... fired it up and the injector pulses water at what appears to be the programmed rate.  Dispensing volume and pressure unknown, but it's pretty quick... maybe approaching the rating of the injector, which is 300cc per minute.

#3 Need to solve pressure regulation before it makes sense to do any measuring... the pump I bought is adding pressure to the system faster than it leaves the injector, and that's with an undersized power supply. I might have gotten a pump that's too beefy (500  ml/ minute and 40psi). Clearly need to get some kind of pressure sensor, and shut off the pump when pressure is above target level, and probably control the current too.  The latex tubing can only handle so much volume before it expands (and that's destructive, it can only handle that a few times).

#4 I didn't have the right arduino pin cables, so I jury rigged with bits of wire and alligator clips.  It works, but if water leaks it's going to short out and potentially electrocute me.  Need to get the right bits and bobs and re-arrange the parts so as to minimize mixing water and electricity.

#5 The jets from the injector come out with a good bit of force.  Looks like some of the nozzles on the used injector I got are clogged... will need to get some brake cleaner and try to salvage the clogged ones.

But yeah, it basically works, and it's pretty clear that it will be able to adjust dispensing rate to match a given  container. (above some minimum drop size, which depends on the pressure, and physical characteristics of the injector).

Yay, fun!

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## Toasterboy

Here's a video of the proof of concept injector setup:



It is configured to open the injector for 80ms, and close it for 50ms. That works out to ~7.69 pulses per second (not 20).  After the video I did another test and measured it dispensing ~100ml in ~91 seconds. I don't think that it's operating at full capacity yet though.

That works out to ~0.14ml per pulse. (which is about 1/2 micron per pulse z level rise in a ~2'x2' container)  Also, the dispense rate would be ~4000ml/hour with this setup, which is about twice as fast as the siphon dripper.  Haven't played with varying the open/close durations yet.

I suppose the next steps are to research and select a pressure sensor, and figure out a better tubing solution, so it will take a while before I'll be able to proceed.  I'm also pretty sure that the latex tubing isn't sufficient to run at the right pressure.... suspect it's well below 40psi currently and will perform better at higher pressure.  I used latex initially because it fails gracefully, and pops like a balloon rather than exploding on overpressure.

It seems pretty clear that this concept can provide some pretty fine control over volume dispensing and timing though.

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## 3dspider

You might try some braided vinyl tubing. The stuff I have is rated for 250 psi.

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## Toasterboy

Yeah, that's what I have in mind to try after I get a sensor (and probably an emergency release valve).  Will the braided stuff hold around 100psi with barb connectors and zip ties?  Rather not have the connections pop off under pressure.

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## erikk

Maybe you can use a whole system from a car -pump, pressure regulator, injector, relays-

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## 3dspider

I usually use barbed fittings and worm gear hose clamps. I'm not sure if zip ties will provide enough pressure.

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## Toasterboy

OK.  I found a $1.56 absolute pressure sensor on Mouser that should work.  Might be a bit of a pain to mount it.  I think I can drill a hole in a PVC Tee joint, glue the sensor die on carefully without clogging the sensor hole (the sensor die is 1.6mmx1.6mm), solder the contacts, and then put hot glue or epoxy over the whole thing to make sure the glue holds. (can then put the emergency pressure release valve on the tee, so it can blow off pressure instead of exploding if the sensor or injector fail for some reason). Safety first.  

Working car parts are generally expensive.  The injector I'm using is unsuitable for use in a car anymore, but seems to work fine for this. (injectors are commonly replaced for various reasons, so they are cheap used).  Not so much with the other parts that might be harvested from a car.

Printed Peristaltic pump+ interrupt sensor and/or a position sensor on the pump wheel is definitely cheaper than the injector approach, and doesn't need pressure, so is also safer.  Injector will probably go faster, and hopefully have more dynamic control over drip size and timing, and thus finer control over the z resolution of the prints.  Likely more expensive in the end though.  Hard to say whether it's worth doing vs the simpler pump hack Rylan mentioned without building and testing it.

Anyway, I'm stuck until I get the sensor in the mail in 3-10 days.

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## Anuvin

I have taken further inspiration from the scientific community and I think that I may have come up with a very effective setup. I have just ordered a 500ml separatory funnel, an 800 ml beaker, and a ring clamp from my favorite local lab supply, KLM Bioscientific. The funnel has a teflon valve, and glass stopper on top, and looks something like this:



I think this tool will be capable of double duty, and will be absurdly useful for separating resin from saline. With the Peachy team nearing shipment of the finished printer, it seems like a good time to start thinking about reservoirs again. Anyone else got any bright ideas for reservoirs?

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## Deadbot1

I'm thinking of custom building my reservoir and build tank from fiberglass. Might try to design them to be a single unit with a peristaltic pump driven drip and recovery setup. I'll probably use a cardboard mock-up as a base and glass it in as I figure out small improvements. Might use a foam core if I decide to try the heated tank system. That way I end up with  a nice opaque insulated tank for the build and an easy to heat reservoir.

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## Alchemy

Has anyone tried salted Tonic water in the reservoir. As most people know quinine fluoresces in *ultraviolet.

*Wondering what it looks like how it effects the print or different liquids effect the drip count.

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## rylangrayston

EDIT:
oops this is a reply to stuff in page one of this Thread... I thought I was reading the end of the thread... oh well there is probably good info in this post any way ill leave it here even if it dosent fit the flow of conversation. : 

In the standard build the printer has a total usable deflection of approximately  45 deg, that is 22.5 deg ether side of zero. 
we typically print with speeds between 50 and 100 mm per second at a distances of 80- 20 mm away from the print head.  
Im pulling all these numbers off the top of my head, but these are good ball park numbers to work with. 

That is the standard setup, we chose to have a standard because peachy printer is so so hack-able that we are going to need some "normal" that we can all 
refer to and test on to get repeatable results. 

So haveing said that you can simply bend 4 wires and make the deflection of the printer 90 degrees, you can remove those 4 wires and get closer to 180 degrees max deflection( which of course is not actually usefully) .  This works by decreasing the spring force in the system.  Lowering the spring force reduces the speed you can rotate the mirror at ( in a controlled fashion) 

The largest build volume we have tested is a printing in a 5 gallon pail. This is just starting to work reliably, and we are still using the dripper! 
Sometimes we print at speeds of about 400 mm per second in the 5 gallon pail we can do this because the printer head is farther away from the resin in the 5 gallon pail setup  so, each degree of mirror rotation counts for much more distance travelled by the laser dot. 
Ether Way the short answer is that we really encurage you to get a standard set up working first, once you have that working you will have the 
basic understandings of the peachy printer, then move to pushing the limits with a Ceiling mounted printer, printing in an inflatable swimming pool, and using a pump. 

I Still think the speed limiting factor for large prints will be laser power, and the size limiting factor will be shrinkage. 
With what we are shipping you can chose to use much more laser power than what is recommended, and there are resins out there that have less shrinkage. So at the end of the day, with everyting I know right now, my intuiiton
is that a canoe is still possible, using 100 dollar peachy printer + a pump or...  alot of drippers.

Thanks for the Great Questions and awesome conversation!

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## MistahBradley

So I've been looking at 3D printing videos for awhile, and doing research on other printers, as well as this one. But I am very confused about the whole print bed being customizeable in size. Would someone be able to point me to the correct direction so I can see how that works? I saw the video on the site, but it seems like the printer is a tiny tower with the resevoir on the bottom, and print bed on top (which seems logical). But How can the peachy print on a larger scale if the mechanics are fairly small? Just a very ill-informed, confused animation-student :/

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## Anuvin

The print bed is custom because the peachy uses a laser to print. See the video on the home page of http://www.peachyprinter.com . At 00:12-00:15 into the video, you can see the complete printer, a 4 inch plastic contraption with a circuit board and the lasers and mirrors and whatnot. This little printer can be mounted to whatever you choose. It shoots the laser into a pool of resin that floats on top of saline. These are the reservoirs we are discussing, the upper reservoir being full of saline, connected to the bottom reservoir, which contains the print bed. The print bed is any surface you choose that resin will stick to, but is currently 1/4 inch steel mesh, raised away from the lower res with risers of some kind, bolts or bits of hose, whatever will work. At :30-:36 you can see the same printer set up with three different reservoir sizes. If you look carefully, you can also see the saline solution with resin on top. The saline drips into the lower res and the drips are counted by the printer, this, along with some calibration, is how the printer knows what the z axis height is. Feel free to ask more questions if this doesn't explain.

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## rylangrayston

Also this video is a bit out of date but most of the info is still helpfull. The one thing that is different is that instead of using your sound card we now ship you a circuit board that is essentially a custom "USB sound card" AKA ( dual Chanel DAC output). 

https://www.youtube.com/watch?v=80HsW4HmUes

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## Anuvin

Just got the separatory funnel I mentioned on the last page. Here is a picture of my setup: 



For those who might consider a set up like this, you can save yourself a good bit of coin on a stand using a barbell weight and a metal dowel. If you have a tap and die kit, you might have everything you need around the house. Take a barbell weight of sufficient size (25 pounds, in my case), drill a hole slightly smaller than your dowel, tap the hole and the dowel, and now you have a heavy duty stand.

If you need even more room to mount clamps to, like for multiple reservoirs or printers, you could by a lab frame, but they cost a ton. With two barbell weights, some 7/16 dowels from a hardware store, and some bar clamps, you can save yourself around $950.

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## MemorianX

Another way to separate the resin and the salt water is to hack to together a separation funnel which could easily be done from a soda bottle where the buttom has been cut off and a hose that can be clamped shut mounted  on the other end

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## MistahBradley

> The print bed is custom because the peachy uses a laser to print. See the video on the home page of http://www.peachyprinter.com . At 00:12-00:15 into the video, you can see the complete printer, a 4 inch plastic contraption with a circuit board and the lasers and mirrors and whatnot. This little printer can be mounted to whatever you choose. It shoots the laser into a pool of resin that floats on top of saline. These are the reservoirs we are discussing, the upper reservoir being full of saline, connected to the bottom reservoir, which contains the print bed. The print bed is any surface you choose that resin will stick to, but is currently 1/4 inch steel mesh, raised away from the lower res with risers of some kind, bolts or bits of hose, whatever will work. At :30-:36 you can see the same printer set up with three different reservoir sizes. If you look carefully, you can also see the saline solution with resin on top. The saline drips into the lower res and the drips are counted by the printer, this, along with some calibration, is how the printer knows what the z axis height is. Feel free to ask more questions if this doesn't explain.


Thanks for the reply, and excuse my late response. Your explanation makes sense because it pertains to the setup in the video (all of it makes sense, honestly), but what I'm having trouble understanding is how someone can make the Peachy Printer work in a build area such as this: http://www.globalindustrial.com/g/st...all-containers

It's the first post on this thread. That's what I'm not understanding :/ if that makes more sense to you, haha.

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## Anuvin

Good question, but the answer may be simpler than you realize. The peachy really can print in any size reservoir. You could use a reservoir as small as a cup of water, or as large as a swimming pool. Here is a picture of my old setup: 


You can see that the reservoirs are card storage boxes for baseball cards. You could use those, or a 2 liter bottle, or a laboratory beaker, or a bathtub, or any other thing that will contain water and has nominally straight sides. It can be cylindrical, rectangular, octagonal, whatever! That is one of the best things about the peachy printer. There is no upper limit or lower limit on print bed size. Very cool feature that you can't get with any other printer.

This is a pretty sophisticated thing, so don't feel bad if this doesn't quite answer your question. Soon, there will be a lot of backers who have the same questions, just as I did when I started researching the Peachy printer. So please ask if this is still not the info you were looking for!  :Smile:

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## Toasterboy

So, been a while since I have posted.  The pressure sensors I ordered turned out to be smaller than expected and just too tiny to successfully solder, so I haven't worked on the project for a while.  I just ordered a different (much more expensive) pressure sensor that should be easier to deal with (it's much larger and comes more or less assembled with leads large enough to solder or alligator clip to easily).  Will post updates again when I have a chance to play with it.  

The results I had before show that the basic idea with using pump and injector will work, and I think that will be useful when attempting to scale up to much larger print reservoirs... just have to regulate the pressure so the tubing doesn't explode on me.  With pressure regulated, the fluid delivery for each pulse should be extremely consistent, and programmable.     Whether it's cost effective or worthwhile to do it this way remains to be seen though. =)  As discussed before, to really scale up the printer design, i.e. to print something the size of a car, would probably need a more powerful laser to keep the print times more reasonable and probably some tweaks to the angular control, in addition to the precision drip control.  But basically feasible.

It's pretty clear that the basic design of the Peachy printer would easily be able to print car size objects given enough time, and/or scaling up to a larger version of the same basic mechanism.  It could really revolutionize rapid prototyping and manufacturing, in addition to the stated goals of making 3D printing accessible to everyone. 

I'm so excited that the Peachy printer is going to start shipping soon!

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## MistahBradley

> Good question, but the answer may be simpler than you realize. The peachy really can print in any size reservoir. You could use a reservoir as small as a cup of water, or as large as a swimming pool. Here is a picture of my old setup: ... 
> ... So please ask if this is still not the info you were looking for!



Thanks again. Would you have an image of a setup of a pool sized printer? Seriously, I can understand setting it up for something like a small cardboard box, but anything bigger than 2x2x2 ft is difficult to understand. Especially since I've never seen one in person before :/

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## Toasterboy

The "print head" for Peachy is basically a laser which is deflected by mirrors controlled by electromagnets.  The print volume is then basically a pyramid or cone below whatever height the print head is mounted at, so the higher it is mounted, the greater the surface area of the print vat can be.

As far as I know, larger print configurations have not actually been tried yet, but from the discussion we know that the Peachy team has focused engineering effort for the 1.0 printer on small print reservoir scenarios (as they should).  There will be challenges in getting larger prints to work well.  Theoretically, the 1.0 printer should be able to print to large areas if it is for example mounted on the ceiling in your garage (depending on the height of the garage ceiling).  However, print times for a large vat will be prohibitive, among other things, so some of the optimizations discussed on this thread would be needed to make larger print scenarios feasible.  That's why folks are playing around with pump hacks to replace the basic dripper, which is great for small print vats, but won't scale well for bigger vats.  It's the first of several components that need upgrading to enable the larger scenarios.  Bear in mind, too, that laser safety with a small vat configuration, and laser safety with something mounted on your ceiling are completely different animals.

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## Anuvin

Toasterboy nailed it. Just imagine the jars you see in the video were pool sized and the printer was mounted higher.

I am going to be doing a bunch of videos very soon, so keep checking the forums and you will get a lot more info soon.  :Smile: 

Here is my unboxing video of the Peachy Printer, if you are interested:

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## MemorianX

Now that's alot of parts, not sure what i expected but it's goign to be fun to assemble

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## quertz

The Video is 16:9 with added black bars to become 4:3 and then the Youtube-Player again adds black bars for it to be 16:9 again.
Now I have a black rim around the video  :Frown: 
But apart from that I like the video  :Wink: 

quertz

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## Anuvin

quertz - Good catch, got that fixed. Thanks for commenting.

Memorian X - Not as many parts for the printer itself, surprisingly few, in fact. Check out my build video:

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## MemorianX

That amount of parts looks more manageable, i just saw both your build videos and they are very well done, it doesn't look to hard to assemble, cant wait till your next videos where the printer does some work

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## Feign

I tried following the official first draft of the assembly video, but then switched to Anuvin's version.  There is a fine art to keeping your hands in the frame of a how-to video while talking about and apparently showing the audience key parts and their orientation on the assembly.  Also the scanner portion was a bit hard to watch...  Hot glue for paper, _really_?  I can't complain about the scanner though, it was basically a freebie along with the printer.

As for the build reservoir, I found a better container to use than a pop bottle.  My wife's favorite drink:
Attachment 8493
Still 2 liters, but the plastic is maybe 50% thicker and completely straight sided.

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## Anuvin

Hey Feign, hope I made things a little easier for ya! The software is up now and I can't wait for you to get a print out. Speaking of...



Just recalibrating and then more  prints to come!

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## rylangrayston

Ah the very first successful print from a backer using a V1 printer! 
been waiting for this moment for a long time. 
Great work everyone.
lets all get up from our computers and go crack a cold one, to celebrate. 
The pic above marks the beginning of a new era for peachy printer.

Cheers, to all the prints to come!

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## MistahBradley

> The "print head" for Peachy is basically a laser which is deflected by mirrors controlled by electromagnets.  The print volume is then basically a pyramid or cone below whatever height the print head is mounted at, so the higher it is mounted, the greater the surface area of the print vat can be.
> 
> As far as I know, larger print configurations have not actually been tried yet, but from the discussion we know that the Peachy team has focused engineering effort for the 1.0 printer on small print reservoir scenarios (as they should).  There will be challenges in getting larger prints to work well.  Theoretically, the 1.0 printer should be able to print to large areas if it is for example mounted on the ceiling in your garage (depending on the height of the garage ceiling).  However, print times for a large vat will be prohibitive, among other things, so some of the optimizations discussed on this thread would be needed to make larger print scenarios feasible.  That's why folks are playing around with pump hacks to replace the basic dripper, which is great for small print vats, but won't scale well for bigger vats.  It's the first of several components that need upgrading to enable the larger scenarios.  Bear in mind, too, that laser safety with a small vat configuration, and laser safety with something mounted on your ceiling are completely different animals.


Well played sir. Thank you everyone for explaining this to me. Been busy with classes and work so I'm super late on the response. I apologize if I made it difficult to explain, or whatnot, but it's hard to visualize without the physical parts, but it makes sense now. So thank you very much :]

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## MistahBradley

Okay well how about another resevoir question? I searched but nothing came up, unless my wording was off.

Anyways:  would it be possible to somehow configure/rig/hack the peachy to print multi-colored pieces? Like invest in a slightly bigger pump/print mechanism to hook 2 resevoirs up to? or is that thinking too far ahead at the moment? :P Just curious.

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## rylangrayston

> Okay well how about another resevoir question? I searched but nothing came up, unless my wording was off.
> 
> Anyways:  would it be possible to somehow configure/rig/hack the peachy to print multi-colored pieces? Like invest in a slightly bigger pump/print mechanism to hook 2 resevoirs up to? or is that thinking too far ahead at the moment? :P Just curious.


great minds think alike...
http://peachyprinter.ipbhost.com/ind...ial-raft-hack/

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## Toasterboy

That's way cool.  You could sort of print in full color that way.  I guess the question is whether you would be selecting one of n colors per gcode line segment (probably simplest way to do it, with n being 3 or 4), or if you would lase the same spot multiple times under different resin pools in order to try to  mix a custom pigment for each line segment, and how well such mixing might work out.  You definitely would not be limited to having whole layers be the same color, but this would probably  slow down maximum printing speed and introduce surface waves to deal with potentially.  Probably is more difficult to pull off the more separate colors are attempted.

Another approach might be to rig a gantry that follows behind the laser spot and dumps or sprays pigment powder onto the curing resin gel.

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## Synchron

i hope that someone would test the color-fill-method.
Print a hollow object with multiple seperate chambers and fill the cambers after the print with colored resin.
The problem is the shrinking of the inner-resin. Maybe it is strong enough to crack the shell.

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## Toasterboy

Resin doesn't really shrink much when it cures in a mold anyway, at least, the casting resins I have used don't.  Plaster and hydrostone are also rather dimensionally stable.  If anything you would have problems with the resin foaming and expanding from contact with water left in the print.   Unless these "fill-behind" chambers are very large with adequate escape vents, you also would have problems with air bubbles and getting your chambers to fill unless you also cast in a pressure chamber, so I would think the raft idea above is more feasible?  Automating the creation of the fill behind chambers in the model might be challenging as well (i.e. like implementing the auto support features of various slicers).

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## oninoshiko

> So, been a while since I have posted.  The pressure sensors I ordered turned out to be smaller than expected and just too tiny to successfully solder, so I haven't worked on the project for a while.  I just ordered a different (much more expensive) pressure sensor that should be easier to deal with (it's much larger and comes more or less assembled with leads large enough to solder or alligator clip to easily).  Will post updates again when I have a chance to play with it.  
> 
> The results I had before show that the basic idea with using pump and injector will work, and I think that will be useful when attempting to scale up to much larger print reservoirs... just have to regulate the pressure so the tubing doesn't explode on me.  With pressure regulated, the fluid delivery for each pulse should be extremely consistent, and programmable.     Whether it's cost effective or worthwhile to do it this way remains to be seen though. =)  As discussed before, to really scale up the printer design, i.e. to print something the size of a car, would probably need a more powerful laser to keep the print times more reasonable and probably some tweaks to the angular control, in addition to the precision drip control.  But basically feasible.
> 
> It's pretty clear that the basic design of the Peachy printer would easily be able to print car size objects given enough time, and/or scaling up to a larger version of the same basic mechanism.  It could really revolutionize rapid prototyping and manufacturing, in addition to the stated goals of making 3D printing accessible to everyone. 
> 
> I'm so excited that the Peachy printer is going to start shipping soon!


Hey tosterboy, how small are the leds? I know I've had luck with SOIC-8 packages which, frankly, I thought were going to be a lot more difficult. If that happens to be your package format, sparkfun sells some adapter boards. The other option for you is, (again you'll need an adapter board, really) is get some solder paste, and you can use a toaster oven as a reflow oven.

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## Toasterboy

The first set of pressure sensors I got were exactly as specified, 1.6mm x 1.6mm... it's just that I didn't realize how small the contacts on the chip would really be and I am a noob with soldering. (us comp sci guys rarely touch actual hardware). It would be cool if there's an easier way to use these, but if not they were only about $1.56 each so no big deal. I do have a toaster oven.
http://www.mouser.com/ds/2/400/AEAC3...580-525808.pdf

Anyway, I got a different Honeywell sensor with a hole mount and leads that are big enough for alligator clips, so it will be much easier to use.  (and I won't have to convert readings in bar into psi with the new one I got).

I think I'll install the sensor into a pipe cap so I can use a pipe T  and nipples to adjust to different tubing in the future.  I can get a second T and hook up an analog pressure gauge also. I have a spare gauge from when I built my pressure pot for resin casting.

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## MistahBradley

> great minds think alike...
> http://peachyprinter.ipbhost.com/ind...ial-raft-hack/


That actually makes more sense than what I had in mind: imagine an external pump connected to 4 resevoirs via tubes.... I'm no engineer by any means xD But at least it has been brought up before. Can't wait to see where the Peachy production ends up at :P

----------

