Parametric Design of Plastic Y-Axis Backplate for 8", 10" or 12" i3v

[PyramidDave]

I have been looking at a way to replace this part for a while & having my clip brackets work so well with the LCD housing & Right side electronics cover, I realized this same idea might work for the Y-Axis Back Plate. I am ready to print my last test prints hopefully & thought I would see if anyone else has some suggestions for this design. I have been bouncing some ideas off of voodoo28 this week who has a 12" i3v. I have a 10" Prusa i3v, so that is the only one I can really test it on. I did get the key dimensions from Colin for the 8" version, so they should be correct. I already had the dimensions for the 10" & 12". I am test printing just the top & vertical profiles before printing the final part. The exploded view of this assembly should show how it will go together. I am not using nut traps, but clips on the sides with 3 holes for M3 bolts. There is 18mm of plastic to go thru, but might be able to countersink the bolts & nuts to use M3x16mm bolts on each side. The 2 peg holes on each side, I made an insert with a M3 hole in the center, so I can put a M3 bolt thru the center of 1 or both peg holes on each side. It seems like that should work. I am using M5 bolts for the middle clips, but may not be able to countersink those since there might not be enough clearance. I started to use M3 bolts there, but M5's for that structural support seem to be needed. I was also pondering some ideas for hole patterns to dissipate vibration & decided to try an f cut under each V-slot like are cut in Violins. I added a few more cuts for the 10" version, but have not added any others for the 8" or 12" before seeing how well these work.

One dimension Colin was not sure of on the 8" was the offset distance for the slots in the top of each side where the heat bed bolts clear. It seems to be the same for the 10" & 12". The dimensions I have for those slots are measuring from the center of V-Slot to the Left side of the slots, I have 36.2mm on the Left side & 24mm on the right.

I could print these 2 backplates in either of 2 orientations, either like they are or back face down. I am planning to print them back face down, since that seemed to work well for the Front Y-axis. I am using openscad for this design & DraftSight for the 2d geometry calculations. I also have an option for a L bracket under each V-slot. I was playing around with an offset angle bracket to use with 12" version that would connect to the side of the V-slot & angled towards the bottom middle. I included 3 screen shots that show the Assembly of parts, the Key dimensions and an earlier version that shows what that angle bracket looks like.

I am planning to print the final version of this in PETG with 50% 3d honeycomb infill.
Let me know if you have any suggestions.Y-AxisBackPlateParametric_10inch_Rev20.JPGY-AxisBackPlate_KeyDimenions.JPGY-AxisBackPlate_10inch_WithVSlotBrace.JPG