Vitamins for Prusa Iteration 2

I've printed a set of parts for Prusa iteration 2. Aside from not needing the bottom plate for the bed, are there any other changes to the vitamins needed? If so, is there a modified BOM somewhere?

Github

That link should take you to it.

I forgot about that. I had looked at that earlier but it didn't seem to be up-to-date. For example, shouldn't there be 5x 608 skate bearings instead of 3 only. The extruder, which is included in the instructions, needs 3 and the x and y axes need one each. It also did not list the smooth and threaded rods. I expect that the threaded rods are the same but I'm not sure about the smooth rods.

Hmm. The extruder plastics are even included in the BOM. Perhaps you should log an issue with the project.

That casts a lot of doubt on the accuracy of the rest of the BOM as well.

Does anyone know the length of the smooth rods for the X-axis? Is the length of 420 mm in the wiki still correct for iteration 2?

Also - surely we need 2 X Z-motor mounts? Anyone printing the parts from that list might have difficulty putting the second Z-motor on, as it only says to print 1x Z motor mount.

...any follow-up to this?

I'm not even sure which *printed* parts are necessary.. I started printing out a Prusa Iteration 2 (never printed the first iteration), and went based on the README in github. That says:

6x frame-vertex-without-foot or 2x -without-foot and 4x -with-foot
2x coupling
3x endstop-holder
1x x-carriage
1x x-end-idler
1x x-end-motor
2x z-motor-mount
4x belt-clamp
8x bar-clamp
2x rod-clamp
1x y-motor-bracket
2x pulley
12x pla-bushing

(which at least has the 2x on z-motor-mount), but the github metric-prusa-lm8uu directory has a bunch of additional files in it:

bearing-guide.stl
belt-clamp-nut-holder.stl
y-bushing.stl

I take it ybrac-t.stl is y-motor-bracket now?

And as an aside, why aren't the belt-clamps using some of the tensionable belt-clamp solutions like [www.thingiverse.com] or [www.thingiverse.com] ?

But still, the BOM for the vitamin parts.. is the one in the bill-of-materials.txt file on github correct?

..Jeff Keegan
[www.keegan.org]

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--Jeff Keegan (Just Another RepRap blog)

That readme does look outdated. I just printed the build plates in the lm8uu folder. But since I'm using a direct drive extruder, I removed the parts and gears for Greg's extruder using Meshlab. The plates looks complete to me.

Yeah I hadn't thought to just look in the plate scad files to see how many were printed out.. All that leaves is the B.O.M. for the vitamin parts. Is this still being worked on?

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--Jeff Keegan (Just Another RepRap blog)

They're still working on it.

Meanwhile, the I understand that the only changes to the rods are with the x smooth rods which are shorter at 405 mm. Kliment also mentioned that they did away with all the M4 nuts and bolts.

brnrd: The extruder is still being held in place by M4 hardware.

Issues or points to take note with the STL files in the release....I'll assume the packs are the same STL's as the individual ones.

Z bar couplings - won't fit 5mm shafted motors
Pulley rings - bearing is loose, and the part fit between the two parts is loose.
Extruder Body- M3 Nut size in the top is too small for the nut to fit
Extruder Pinch wheel - pocket for the M3 nut is too small
Large extruder gear - recess area for the Head of the hobbed bolt is too small for common hardware.

All these points could be adjusted/fixed in SCAD if your comfortable do so.

The hole in the x carriage in the set that I printed had holes for M3 screws.

Also, the M3 nut size is small on purpose so that the nuts can be inserted while heating the nut with a soldering iron as shown in Prusajr's video.

The M8 nut size was too large (14 instead of 13 mm) apparently to accomodate SAE and metric nuts. But my SAE and metric nuts were both very loose. I might try printing a spacer (single walled hexagon) and see if that works.