# Specific 3D Printers, Scanners, & Hardware > RepRap Format Printer Forum >  Geoff's Mini Kossel Adventure

## Geoff

Hai!

***Edit now that it is finished and working... I have to say, this is the quickest, easiest printer to build.

2 days build time - taking it slowly, I could do it in half a day now after building one. Calibration took about a day of tweaking, another day of just adjusting and tightnening things, belts etc, getting all the little artifacts out of the prints, and yeah.. about 3-4 days total buld to print time and it was my first one. The prusa took me days to build, ordering more parts, printing more crap... and it was about a 2 week process of getting it right, and still, the delta prints are AWESOME!!!

This is hands down the best machine I have used for 0.1mm prints... it is flawless, zero wobble and backlash, even if your print comes unstuck from the bed, there is so little backlash the thing doesnt move!! not joking, my hats off to you Mr Kossel, you design a magnificent printer.
*
Well, I thought I would have a crack at building a mini Kossel, mainly for the small footprint they have, which is only about 30cm wide, fits neatly on my desk  :Smile:  

I started my journey by buying one of Blomkers kits,  and while all his parts were great, the plastic frame parts he sent were unusable. 

The picture below is the reason I not only decided to print my own parts, but also because ABS in my simplistic brain is far more durable, stronger and overall more feasible to use when *building* a printer.

"OH BUT PLA IS FINE!!!"

Ok ok calm down, I didn't mean to offend you PLA fanboys, but let's face it - it *does* degrade over time, no one can deny that. ABS *does not* degrade.

This is the Orange 'Blomker Industries" PLA parts I was sent, they all have the same warped split quality. If I didn't have my own printer and ability to make my own parts, I would have been very angry.



I don't think I need to point out the issues with these parts. The main one, the Openbeam 240mm V-slots DID NOT fit in the holes, they were so far out I had to drill new ones, and then the structure was so weak, 
they split like  when it was all put together..

So using my flashforge in 1 day, i pumped out all my kossel parts AND prusa parts, the flashforge was glowing red hot by night time... 20 hours straight printing.

YES ITS A MESS!
The prusa build is my "Tinker' machine... I *plan* on it never being finished and upgrading it constantly. haha



Base was relatively easy, now onto the rest




Gizmo the cat, photobombing...




And we are almost there, there is more done than this photo, but still messy, am doing the final wiring hookup tonight and then the auto level probe..

of all the things I didn't have in my house, a safety pin... I can't believe I didn't have a safety pin lol... so yeah tonight is test night

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## jaguarking11

That looks very good. I am curious what is the build volume supossed to be? 300mm footprint, in my mind there is around 200mm cylinder capable? How about height?

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## DrLuigi

Nice printer, Liking those Black aluminium bars, How did this kit cost anyway?

Ive been thinking to get my printer all taken apart and making a Delta, But aint sure yet at this moment.

They look damn awsome and have some nice speeds without to much vibiration nor sound.

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## jimc

I do like the biohazard gear! Cool

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## Geoff

> Nice printer, Liking those Black aluminium bars, How did this kit cost anyway?
> 
> Ive been thinking to get my printer all taken apart and making a Delta, But aint sure yet at this moment.
> 
> They look damn awsome and have some nice speeds without to much vibiration nor sound.





> Nice printer, Liking those Black aluminium bars, How did this kit cost anyway?
> 
> Ive been thinking to get my printer all taken apart and making a Delta, But aint sure yet at this moment.
> 
> They look damn awsome and have some nice speeds without to much vibiration nor sound.


if you bought the parts seperately, about $400, but in a kit with everything ready was about 600, but now I know what's in it and what I can get parts for, it wont be anything near that price.

#1 most expensive item is the bearing sliders for the arms, from $50 onward each... i see now why people use V-slot runner wheels instead ... 

The aluminum bars are $18 for 1 meter, I bought 10 meters, but you need to calculate your grinder size as you will lose like 3mm per cut, the black are like out of stock everywhere .
M3 screws are much required in this kit, there is 16xM3-15 in each base foot, 5 in each top.. 

Allen key / spring / safety pin / endstop microswitch makes up the autolevelling feature..

Traxas rod ends and graphite rods so easy to get... everyone has got them... 

The speed is unbelievable from what I have seen, for me it means double the reliable speed at 150ms feed rate.




> That looks very good. I am curious what is the build volume supossed to be? 300mm footprint, in my mind there is around 200mm cylinder capable? How about height?


My round glass plate that came with it is 180mm, but I have a boroscillate round glass at 170mm and a 160mm *round* hotbed,  so will prob use the 170mm.

I find height is what I want more, and the kossel mini is rated to 240mm high prints!  so I will have a print area of 170x170x240

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## Mjolinor

I decided to see how cheaply it was possible to make a delta printer. This one is under $100 so far not including the Azteeg board.

It's a long way off finished, I am currently making a multi extruder hot end and Bowden push thing for it. It doesn't look as nice as yours but it should print fine. I have run it for hours as it is and it's repeatability surprises me even though it has string to move the axes instead of steel Bowden cable. I bought some steel cable for it and it worked very well but after 20 minutes or so the strands started snapping because of the tight bending radius of the pulleys, I need to source some good flexible cable for it really but that can wait.

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## Geoff

Nice work! 
Oh man I like your workshop... i'd be like a kid in a candy store in there lol  :Smile:

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## Mjolinor

It is a good mancave but it's a bit overfull though when one is reduced to building printers on the only spare seat in the room.  :Smile: 

http://homepage.ntlworld.com/dknpowe...es/mancave.jpg

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## jaguarking11

> My round glass plate that came with it is 180mm, but I have a boroscillate round glass at 170mm and a 160mm *round* hotbed,  so will prob use the 170mm.
> 
> I find height is what I want more, and the kossel mini is rated to 240mm high prints!  so I will have a print area of 170x170x240


That must be one fast beast. Are you looking into light weight build for the head? I have an idea of making the carriage and the hot end one part. Should reduce the number of steel fasteners and reduce the weight drastically. IF your printing in abs, use abs carriage, if your printing in pla still use an abs carrige. My pla parts warped after 2-3 prints. 

I went oversize with my build and I am using abs, this means the main moving parts are like 2x the weight they should be, maybe more. Tuning and tweaking is next.  I am liking the alu extrussions. I will be experimenting with a different rail system once I have my heated chamber built. I printed a 220mm long part yesterday. It took about 12 hours, and at the end I had some ridiculous lift on the edges. The part is still usable as it looks like a uniform lift, but the part warped 3mm on each corner. I have to get a heat spreader and heated chamber built asap or else this thing wont be able to do the rest of the parts I need.

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## Geoff

> That must be one fast beast. Are you looking into light weight build for the head? I have an idea of making the carriage and the hot end one part. Should reduce the number of steel fasteners and reduce the weight drastically. IF your printing in abs, use abs carriage, if your printing in pla still use an abs carrige. My pla parts warped after 2-3 prints. 
> 
> I went oversize with my build and I am using abs, this means the main moving parts are like 2x the weight they should be, maybe more. Tuning and tweaking is next.  I am liking the alu extrussions. I will be experimenting with a different rail system once I have my heated chamber built. I printed a 220mm long part yesterday. It took about 12 hours, and at the end I had some ridiculous lift on the edges. The part is still usable as it looks like a uniform lift, but the part warped 3mm on each corner. I have to get a heat spreader and heated chamber built asap or else this thing wont be able to do the rest of the parts I need.


I have to admit. it's the first machine I've used/built that has a feeder external to the head. I have never really liked the idea of feeding the filament from half a meter away from the head.  I am keen to try it to see how light it makes it and if they makes much of a difference, all I can go on is youtube videos so far and they look great

I would love to say I used a couple of machines to print my kossel parts, but the only one I could get the corners to print without warping was the flashforge, with 50% infill they take a long time to print need a fair bit of heat.

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## Geoff

I thought I should put some finished shots up, thanks again to Roxy as her help with my issues got me printing finally, and the output so far has been great. It needs some tweaking but so far so good... and yeah some things I will change like the carriage belt sliders, but for now I just want to get it calibrated before I go trying to 'improve' it... so far it prints pretty nicely for a machine thats barely been setup.

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## Kingoddball

Really nice!
I started a delta.. Stopped as 3 prints - Might pick it back up again now!

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## nka

Altrougt I love the Delta design. I'll be moving to the CoreXY. Just becose I dont have the time to tune it right... and I'll wish to have something a little bigger than 170mm. And it should be more solid (less chance of having to recalibrate when moving it.

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## Geoff

> Altrougt I love the Delta design. I'll be moving to the CoreXY. Just becose I dont have the time to tune it right... and I'll wish to have something a little bigger than 170mm. And it should be more solid (less chance of having to recalibrate when moving it.


Can you clarify something for me please?

The Core X/Y.

Is that basically what my flashforge is? Z moves up down, the carriage moves X/Y? 

I agree strongly on the moving the printer comment, I can put my flashforge on its SIDE and it will still print (_I am not joking... it will print at 90 degrees_ and the steppers are strong enough to hold it all ) I flipped it up to check underneath when it was printing once, I left it standing on its side and the print was not affected at all, should video it actually!)

The delta, if you pick it up the frame can flex and thats bad as you know... luckily the autolevel does do a good job and compensates somewhat.

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## Mjolinor

CoreXY just moves both X and Y motors off the carriage making the inertia of the head very small because the moving mass is very small.

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## Geoff

> CoreXY just moves both X and Y motors off the carriage making the inertia of the head very small because the moving mass is very small.


that totally didnt answer my question  :Big Grin:

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## Mjolinor

> that totally didnt answer my question


Sorry

No

Is that better.  :Smile:

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## paradiddle65

> that totally didnt answer my question


Your Flashforge has an "H-bot" style XY gantry, AKA the X axis stepper moves with the extruder carriage. A CoreXY design is similar to an Ultimaker; both steppers are stationary and utilizes two crossing belts to more the extruder.

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## nka

> Is that basically what my flashforge is? Z moves up down, the carriage moves X/Y?


Yes, exactly. Everything is printed from top to bottom (Z Axis bed is moving to the bottom). XY are drived with 2 stepper using crossbelt and three carriage (2 for Y, 1 for X).

www.corexy.com for the "XY part", just need to add the "Z".

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## MK-X

Core XY is a very nice platform, I just don't like dealing with Z-wobble.

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## Geoff

> Yes, exactly. Everything is printed from top to bottom (Z Axis bed is moving to the bottom). XY are drived with 2 stepper using crossbelt and three carriage (2 for Y, 1 for X).
> 
> www.corexy.com for the "XY part", just need to add the "Z".


Ok I got it now, I think that would be like the Mantaki I saw where the head is on an X and Y slider with cross beams coming out all 4 sides of the head. 

I am not sure now what to build next lol... I am so happy with the Delta and the fact it not only doesnt wobble, but can print when something isnt even stuck to the build plate (literally.. when I say mine has no backlash, I don't know whether my belts are just super tight or what but man... i have never seen a printer work so well when a print is failing.

I printed a 10cm tall bust, I heard a cracking noise about halfway, and I knew the crappy first layer I saw go down came off, it was my fault for not restarting the job when I saw it, but I saw to hell with it, print away  

... but it was a 4 hour print and I was 2 hours in... oh man what do I do??

I paused the job, positioned the bust back to where it was supposed to be (which was easy to see thanks to the brim) and resumed printing, I held my breath... HOLY CRAP.. it worked. It printed 2 hours worth of 0.1mm printing without so much as knocking the model more than 0.5mm. A couple of small step lines  - but for a job that was not stuck to the plate, i have to say for zero wobble at all, kossel seems to be the winner there.

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## Geoff

Printed my first Bust on the kossel!!
This is my walter white sculpt from thingiverse

http://www.thingiverse.com/thing:459366

0.2mm, 10%infill, no raft or brim... 3 hours.. came out great

kosbust.JPG

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