by Tdeagan » 2013-Jun-Tue-22-Jun
Thank you so much! It's really helpful to have someone else looking at this.
The blocks have 4 set screw holes but the set only came with 2 set screws per block (which should be fine.) The image I'm playing with in my mind right now is replacing the two wood perpendicular cross pieces with pieces of aluminum bar stock. These would attach to the blocks via the set screw holes on one side and two new tapped holes on the block's bottom. They don't even _have_ to attach to each other at that point. If my machining mojo is good, I could mill out the tabs that attach to the frame and tap them (heck, as long as I'm fantasizing, I might as well mill out the cross cuts to hold the nuts

In any event, the block could serve to hold the cross pieces at a right angle, the bar stock could serve to anchor the assembly to the frame.
I like the approach you're taking, I just have a terror of working with wood. I can generally machine to a few tenths ( 0.0001") on my little Sherline, but I can't manage to cut wood to an eight of an inch to save my life

I had a hard time deciding to buy the blocks from Printrbot or make my own (that'll teach me!) Too bad the deck is too wide for the PB+ print bed or I could try printing one!
Maybe I'm not thinking far enough out of the box, maybe I should be trying to think of a way to mount these on top of the deck instead of below. If I have to start modding the frame, might as well leave it rigid and add to it instead of subtracting. My other plans are to drop the printrboard and put in a RAMPS 1.4 for the dual extrusion capabilities. I've just about finished my bowden conversion.
Thanks again for the help!!
--tim
Tim Deagan
KC5QFG
(optional Dual Extrusion) Printrbot Plus V1 [3/2013]
bed stabilizers, bed levelers, Y & X belt tensioners,
50mm fan mount, LED ring light, Z-axis screw Isolators,
Z-shaft stabilizers,optional Bowden conversion, GT2 belts/pulleys,
M8x1.25 Z Screws, Flex. Z-couplers,
RAMPS 1.4 w/ LCD,
Quick Change Extruders:
Option 1- Dual hybrid geared Wade's/Bowden w/ 3mm & 1.75mm Ubis,
Option 2 - Dual direct geared Wade's w/ 3mm & 1.75mm Ubis
Option 3 - Single geared Wade's w/ 3mm or 1.75mm Ubis
Option 4 - Single belt drive Wade's w/ E3D
MIC-6 metal bed
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