Filament monitor for FlashForge printers

I had just posted about our Tunell filament monitor on the 3D printer parts forum, but I wanted to bring it especially to the attention of the group here -- the Tunell monitor was desgined specifically to connect easily to the FlashForge Creator (and other machines that have the 4-pin endstop cable Mightyboards and running Sailfish firmware). For those of you doing long-running prints or need production reliability, this device can pay for itself very quickly by detecting out-of-filament and other filament feeding problems, and pausing the printer. More details are on the Tunell monitor page at ToyBuilder Labs.

Thanks.

I'm new to 3D printing and like this upgrade.

But I'm wondering, if the print gets paused.....say for 4 or 5 hours....can you just restart a paused print with no problem?

Short answer is it's fine.

The more nuanced answer: because pausing the print may allows the part and the printer (heated bed, nozzle) to cool down significantly, there's a chance your part will shrink or warp enough that when the print is resumed, you could end up with seam lines and/or gaps at the point where the stop and restart happened. The extent depends on the amount of cooling and the material. In some cases, people use temperature-sensitive bed material that results in the print popping off the print bed when cool. If that's the case, long period of cooling can still result in a failed print, but at least you won't be running your printer continuously without fresh filament.

thanks. That helps

With my setup, pausing the printer for more than 20-30 min would kill the print anyway, and for 90 bucks (dual extruder) there is very little ROI versus a simple end of spool sensor connected to a MySensor.org sensor to send notifications. The price has to come way down for it to work for my setup.

Its worth mentioning that your print may loosen from the build platform when it cools.

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Originally Posted by Sebastian Finke

Its worth mentioning that your print may loosen from the build platform when it cools.

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Yes. I did point that out earlier - for build plates that tend to release upon cooling, if you have cool-on-pause enabled, it will cause the print to come off. If you use heated pause, the part won't come off, but you may still have shrinking of parts, enough to show a seam line.

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Originally Posted by ServiceXp

With my setup, pausing the printer for more than 20-30 min would kill the print anyway, and for 90 bucks (dual extruder) there is very little ROI versus a simple end of spool sensor connected to a MySensor.org sensor to send notifications. The price has to come way down for it to work for my setup.

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Well, the Tunell monitor is intended for uses where more sophisticated monitoring is desired -- clogged nozzle, knotted up spools, filament diamter way over or under size causing feeding problems, filament that broke inside the feed tube, etc. UPDATE: And, of course, when the filament has run out.

For anyone that wants a simple out-of-filament detection, you could just wire a microswitch to the printer -- that would be the least expensive way to go.

You mean to tell me these 3D printers won't detect when the spool runs out ?

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Originally Posted by Ward

You mean to tell me these things won't detect when the spool runs out ?

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That's the most common use case for the Tunell monitor -- to detect when the filament has run out -- but it also is able to detect other filament feeding problems. Sorry for the confusion!

Here are some videos from Aaron Tunell, the original creator of the Tunell monitor. We have a collaboration with Aaron and are now selling an upgraded version (Version 4) now.

Filament running out: https://www.youtube.com/watch?v=JWRNVMoyRus
Filament getting stuck: https://www.youtube.com/watch?v=ItIOlt-Mq-k
Dual-monitoring: https://www.youtube.com/watch?v=Kw9-eVxrqn8

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Originally Posted by toybuilder

That's the most common use case for the Tunell monitor -- to detect when the filament has run out -- but it also is able to detect other filament feeding problems. Sorry for the confusion!

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I'm sorry. I meant the printers....not your sensor. I figured your sensor device could do it.
I fixed the post above.

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Originally Posted by Ward

I'm sorry. I meant the printers....not your sensor. I figured your sensor device could do it.
I fixed the post above.

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Oh! :)
That's correct - almost all printers that I know of do not check for filament right out of the box.

lol why don't people check how much filament they have BEFORE starting a print ?
The slicer tells you how much you'll need. It's not rocket science :-)

These days I don't get snags or snaps - you just need to buy the right filament. Had a few when I was starting out.

Never run out of filament - 'cos i check before starting a print.

But there are going to be alot of people who don't take sensible precautions and if you've got a bunch of machines going, a sensor might be a good idea.

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Originally Posted by curious aardvark

lol why don't people check how much filament they have BEFORE starting a print ?
The slicer tells you how much you'll need. It's not rocket science :-)

These days I don't get snags or snaps - you just need to buy the right filament. Had a few when I was starting out.

Never run out of filament - 'cos i check before starting a print.

But there are going to be alot of people who don't take sensible precautions and if you've got a bunch of machines going, a sensor might be a good idea.

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I would be grateful if you could tell me how to do that.
I know that software like S3D tells you how much filament you will need but lets say for example it says I need 2500mm of filament. (random number)
How do I know I have at least that much and not 2400mm ?
Would I have to take it off the spool and measure it?

I wonder if you could use something like this (if you made a groove to guide the filament) ?
It would be even cooler if you could set it to count DOWN from the total length of the filament on the spool backward to zero. :-)
Provided there's accuracy.
Attachment 7885

Quote:

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Originally Posted by Ward

I would be grateful if you could tell me how to do that.
I know that software like S3D tells you how much filament you will need but lets say for example it says I need 2500mm of filament. (random number)
How do I know I have at least that much and not 2400mm ?
Would I have to take it off the spool and measure it?

I wonder if you could use something like this (if you made a groove to guide the filament) ?
It would be even cooler if you could set it to count DOWN from the total length of the filament on the spool backward to zero. :-)
Provided there's accuracy.
Attachment 7885

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Well, we don't have filament odometer implemented in the Tunell monitor, but that is one of several potential future updates to the product that I had in mind when I redesigned the Tunell monitor to the current version.

On Mightyboard machines (like the FlashForge Creator), there is a filament odometer feature. It's a bit hidden in the Utility menu, but it's definitely there!

BTW, we've further lowered the price on the Tunell monitor for our Black Friday weekend sale (we've got stuff up to 50% off).

I just received my dual monitor in the mail, and am downloading some brackets for it. I will have an update for you all this weekend.

Hello all,
I had purchased this filament monitor from Toybuilder.com on Black Friday. I printed this bracket, http://www.thingiverse.com/thing:695387, and after a few modifications everything is mounted and working
.Attachment 7955The circuit board end of the wiring goes in the black socket in the middle of the picture, along with the 3 gray wires
.Attachment 7957The monitor wire can be put into the split loom which will keep it from being damaged. To open these brackets insert a small screwdriver as shown and the bracket will pop open.
Attachment 7958I had wanted to continue the sensor wire in the split loom but the sensor wire needs another 1/2" to do so. The sensor wire is JUST long enough with little room to spare.
Attachment 7960The brackets that I printed needed to have this slot moved more towards the back. Move this slot 1/4" towards the silver mark. I modified the one I printed with my Dremel tool. Also, the wiring connector slot, on the back face, needs to be moved outward another 1/8" so the sensor will sit flush in the bracket.
Attachment 7961I used eight 4-40 sheet metal screws 1/2" long to assemble the bracket. Note that I mounted one sensor, the bracket and then the other sensor. I did not like the amount of tension on the gray ribbon cable from the split loom.

Other notes:
I cut 6 1/2" from the black plastic filament guides and discarded. If you do not add a filament tube below the sensors, you can now load the filament from the front of the printer!! Nice!

Remember you must press the red reset button whenever you start a job or take the pause off. Fortunately, this button is on the right side of the sensor when standing in front of the printer. Nice!

In all this sensor fit well and seems to be working correctly but my first failure will tell. As noted on tunell.us there is a timeout that is settable for no movement of filament. I am going to look at that further to see if it is the right amount.

This hardware, along with the UPS I added, should save a lot of time from failed prints.

Enjoy.

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I would be grateful if you could tell me how to do that.
I know that software like S3D tells you how much filament you will need but lets say for example it says I need 2500mm of filament. (random number)

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it also tells you what weight of filament you will use. and what it will cost.
Even makerware desktop tells you that.

As long as you tell is3d what density the filament is and what it costs per kg. Manufacturers pretty much always have the density info on their websites. Although unless you're using something like bronzefill - the densities don't change enough to generally worth worrying about.

so what you do is weigh a new roll of filament. Take away 1kg and you'll have the weight of the reel.
You can simply weigh a roll before putting it on the printer - make a not of how much filament it has and every time you print something, take that weight away from your starting figure.
Digital scales are cheap: http://www.amazon.com/Ozeri-Digital-...digital+scales
http://www.amazon.co.uk/Savisto-Elec...digital+scales

Way cheaper than sensors.
I really don't see what the problem is or why anyone would print something for which they didn't have enough filament.

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Originally Posted by bkochis

Other notes:
I cut 6 1/2" from the black plastic filament guides and discarded. If you do not add a filament tube below the sensors, you can now load the filament from the front of the printer!! Nice!

Remember you must press the red reset button whenever you start a job or take the pause off. Fortunately, this button is on the right side of the sensor when standing in front of the printer. Nice!

In all this sensor fit well and seems to be working correctly but my first failure will tell. As noted on tunell.us there is a timeout that is settable for no movement of filament. I am going to look at that further to see if it is the right amount.

This hardware, along with the UPS I added, should save a lot of time from failed prints.

Enjoy.

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Besides the cost of this thing and it's limited capabilities, that right there is a serious deal breaker.

At the current cost, I would want these functions added:
1) This reset chore to be automated by the printers control board.
2) I would also want a filament width measurement system.
3) A way to notify (text or e-mail) me when a failure is detected.

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Originally Posted by ServiceXp

Besides the cost of this thing and it's limited capabilities, that right there is a serious deal breaker.

At the current cost, I would want these functions added:
1) This reset chore to be automated by the printers control board.
2) I would also want a filament width measurement system.
3) A way to notify (text or e-mail) me when a failure is detected.

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#1 depends on the printer to signal a start of a new job to the monitor. The monitor itself could support this feature. In fact, one could wire already wire a signal line to the RST pin on the expansion connector to do this.
#2 Width measurement would add complexity and cost; and would require software on the host software or firmware on the printer to do something useful with the information. I believe people at SD3D is trying to do something along those lines. On Sailfish-based firmware (FF's for example), there's no good way for dynamically compensating for filament diameter, as the x3g format specifies target positions in stepper counts.
#3 Would require additional hardware to connect to the network, which this device cannot do on its own. Your sensors.org idea could work, though.

The reason for the manual reset of the sensor is simply because there's no other way to tell the difference between an end of a print job and a failed print. So the Tunell monitor is designed to take a "start of job" signal in the form of the reset button. As I mentioned, with additional development (firmware on the Tunell monitor and the firmware or software of the device connected to the monitor), it would be possible to automate this process.

All,
I installed this monitor on my FF Creator Pro and have run it for several days now. Initial thoughts: Works Great! :cool:

I had 2 prints pause because of knotted filament. I was able to back up to the utilities menu, unload, straighten the knot, reload, and 'unpause' the printer. There was no noticeable flaw in the print job. I was using Makerware 2.4 at the 'Standard' settings and a 10 second delay on the monitor

For this printer, I would extend the mounting rails so the filament entrance is aligned with the center of the spools which would decrease the potential problems. I had to remove the filament tube holder, https://www.thingiverse.com/thing:409297 that I had installed.

Major note: the slower the print speed the longer the delay needs to be otherwise the monitor pauses the printer frequently. I was testing Ninjaflex filament at 30 mm/sec print speed and had to increase the delay to almost 30 seconds.

Enjoy!

Quote:

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Originally Posted by toybuilder

#1 depends on the printer to signal a start of a new job to the monitor. The monitor itself could support this feature. In fact, one could wire already wire a signal line to the RST pin on the expansion connector to do this.
#2 Width measurement would add complexity and cost; and would require software on the host software or firmware on the printer to do something useful with the information. I believe people at SD3D is trying to do something along those lines. On Sailfish-based firmware (FF's for example), there's no good way for dynamically compensating for filament diameter, as the x3g format specifies target positions in stepper counts.
#3 Would require additional hardware to connect to the network, which this device cannot do on its own. Your sensors.org idea could work, though.

The reason for the manual reset of the sensor is simply because there's no other way to tell the difference between an end of a print job and a failed print. So the Tunell monitor is designed to take a "start of job" signal in the form of the reset button. As I mentioned, with additional development (firmware on the Tunell monitor and the firmware or software of the device connected to the monitor), it would be possible to automate this process.

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Thinking outside the box, brings features that add value to a product. Currently the cost verses the value of the product is to great for me, but again that's just me.

Outside the box thinking: (a few example)

1) Monitor machine wattage : If watts > X and filament stops, go into fault. No need for user intervention.
2) Add small display to simply display average filament width over distance. Yes it would require more technical expertise but it's a HUGE value to the product. If it was easy, then everyone would be doing it.. :p
3) Maybe out of the scope of the device, but you must admit, it's main purpose is notification, and hence far more value over a simple tone.

I don't mind spending money on things, but there has to be value to the device, IMO currently this device does not have any more value then the $25 alternatives out there. Cheaper if you build one yourself.

I hope you keep working on it and improve and expand it's functionality, because I think the idea is sound.

I need something like this so I can tell when this cheap a$$ SainSmart filament breaks.

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Originally Posted by ServiceXp

1) Monitor machine wattage : If watts > X and filament stops, go into fault. No need for user intervention.
2) Add small display to simply display average filament width over distance. Yes it would require more technical expertise but it's a HUGE value to the product. If it was easy, then everyone would be doing it.. :p
3) Maybe out of the scope of the device, but you must admit, it's main purpose is notification, and hence far more value over a simple tone.

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#1 and #2 adds more complexity to the device. If you can do it for $25, great!

#3 - I think the Tunell monitor's approach of pausing the printer is the right way to go. Sending a notification without pausing the printer won't help if you're not there to fix the problem right away. Similarly, those simple filament detectors that just turns on an alarm have the same problem - you have to be there to hear it.

Just about anyone can do this for much less then 25 bucks. With this and this we are talking less then 5.00 really, albeit only detecting outages, add a MySenors board (another 10 bucks) and you have a communicating system (for those who have that infrastructure already setup) that will push alerts to any number of people.

If one wants to get really fancy, use a simple encoder, and CT circuit on the same MySensors 'board' and you have a monitor (not just detecting outages), and current sensing system for printer state detection (no need to hit a reset switch on every start) along with a communication system, all for around 40 bucks.

I know it sounds like I'm hassling you over your project, and perhaps that is a bit true.:p I'm not saying your product is bad, I'm just saying for ME the ROI is way to low. For those that lack the motivation/time and have the money to spend; your product looks like its perfect for simple filament movement detection.