Some Enhancements

[whi-tw]

Hello!

So, I've been looking for a good buffer solution, and this one works really well!

I have made some changes. Unfortunately CadQuery won't work properly on my machine (M1 Mac), so I have had to use the tools I am used to (onshape). Unfortunately this has meant I've had to re-design a number of parts, as 'deriving' from STEP files is a bit garbage.

The onshape document is here: Printable Single Buffer - Onshape.

Key changes:

• add some extra geometry to the shaft the bearing sits on, to ensure the bearing sits in the right place, not too close to either of the covers
• Increase the size of the hole on the 'back' of the wheel, to stop it from rubbing against the center of the bearing
• Allow an ECAS bowden inlet to be used, rather than a screw-in one (I have a large number of these left over from my ERCF build).
• Create an extra part to allow the 'wheelhouse' to be magnetically attached to the rest of the buffer, rather than screwed in.
  • This makes threading new filament in, and allows the wheel to be more enclosed
• Increase the diameter of the cutouts in the wheelhouse, to increase clearance to avoid rubbing.
• Improve alignment of filament inlet, so the filament goes in a straight line directly to the edge of the wheel

I've also redone all the extensions, so they all match. The 150mm one seems different to all the others, and seems to be 'right'.

This means the BOM needs:

• 4x M3x8 SHCS
• 2n M3x8 SHCS (n=number of buffer extensions)
• 1x M3x12 (potentially should be longer)
• 1x 608ZZ
• 4x 3x6mm magnets (same as the ones in the ERCF BOM)
• 2x ECAS bowden inlet

I haven't yet had a chance to investigate mounting, but that's my next job.