Prusa I3 on a budget

Dermot · 16 February 2019 14:34

https://londonmakerfestival.co.uk/well-have-3d-printers-but-then-you-knew-that/

mikekelly · 17 February 2019 13:57

Hi @Dermot
There’s a good chance I can make it along. If I’m free I’m happy to bring it. I could bring my drawing machine too if there’s any space for it?

dsikar · 4 March 2019 13:55

Anyone up for continuing the builds tomorrow evening?

peter_hellyer · 4 March 2019 13:58

I’ve wombled my way though mine (except the electicals, which have me scratching my head), but at some point would love a ‘tuning and twiddling etc’ session.

dsikar · 5 March 2019 15:53

Could you please post the link for assembly instructions - the page you are looking at the last group build photos?

peter_hellyer · 5 March 2019 16:27

You’ll mostly need this: https://manual.prusa3d.com/c/Original_Prusa_i3_MK2S_kit_assembly

but when it comes to the extruder, its this upgraded titan extruder: https://www.thingiverse.com/thing:2065461

peter_hellyer · 5 March 2019 18:48

oh, and also be careful with routing the cables , dont get ahead of yourself but instead leave it until the last minute! also make sure to get the legs of the frame the right way around!

I also found the nut-traps to be a little loose on the legs so made 6 of these, which combined with a little hot/super glue, you may or may not find helpful

dsikar · 5 March 2019 21:40

Thanks @peter_hellyer. Would you and/or @mikekelly be able to post photos of z axis assembly?

dsikar · 6 March 2019 00:25

Also @peter_hellyer @mikekelly did you have to adjust lengths for any of the smooth rods?

dsikar · 6 March 2019 01:38

Furthered the build a bit more:
Front view

Side view

Top view

Plenty of activity - great to see welding going on !

And Howard fine tuning his dulcimer

mikekelly · 6 March 2019 17:24

No. I had to trim the threaded rods though, the ones used for the y-axis structure.

mikekelly · 6 March 2019 17:25

I’ll post some pics when I get home or tomorrow. Anything in particular you need to see?

dsikar · 7 March 2019 08:33

Thanks - I’ve manage to womble frame together. Orthogonal view would be grand to get an idea of your cable management solution.

peter_hellyer · 7 March 2019 10:05

@mikekelly what diagram did you follow for the wiring? I’m having quite a few problems getting the steppers working. Also keen to know how you wired up the endstops and PINDA probe?

mikekelly · 7 March 2019 11:30

@peter_hellyer instructions for generic Ramps 1.4 boards should work. This one for example looks right: https://www.reprap.org/mediawiki/images/0/06/RAMPS_dossier.pdf
See the image after the Contents page.

It is important to get the polarity right with the end stops, or you could damage the board. See my pic below. In our build the Pinda probe is effectively the z-endstop, so that connects where the z-endstop should be.

Stepper orientation doesn’t matter apart from determining the direction of travel. If it moves the wrong way plug it into the board the other way round. On the other hand if your stepper is just juddery rather than turning smoothly that would mean that the poles of the motor are not wired correctly. But i think we tested all the ones we wired up so that shouldn’t be an issue.

mikekelly · 7 March 2019 11:35

@dsikar Are these useful?

One thing you might consider doing differently is wiring the cables from the heated bed to the middle entry point in the box which houses the arduino, instead of the one at the bottom. That will stop it dragging against the frame. My wires were a bit too short to do that comfortably.

Also you can see I didn’t trim and rewire all the cables just yet, so they would fit into the box. I just tidied the excess with a cable tie for now. (2nd pic)