Improving Rigidity?

[Mhagan]

now we need someone with cad skills to make it for us.

I got some CAD skills, just give me some specs and I'll crank it out.

I also got CAD, I will look up a suitable screw on MCmaster and draw something up tonight

[Mhagan]

I have drawn up a knob that you can press fit and/or glue on to a 6-32 socket head Cap screw. I used Mcmaster Part number 92185A165 to model the knob

[Eaglezsoar]

I have drawn up a knob that you can press fit and/or glue on to a 6-32 socket head Cap screw. I used Mcmaster Part number 92185A165 to model the knob

Thank you for creating this, it should make it easier to adjust the stop screws and improve the repeatability.

[Mhagan]

No problem, I am happy to contribute to the community.

Let me know how it works I made some guesses regarding tolerances. With the acrylic enclosure I made on my printer, my printer calibration has been rock solid. So, I will not likely be installing these on my own machine.

[bubbasnow]

FWIW, the acrylic pieces seemed to limit much of the variability I was having around the hotend and the zero was very close today.

Can we see a photo of this acrylic piece?

[img]http://i.imgur.com/E9r0gyM.jpg[/img]
The entire effector plate can now be moved by moving the bowden clamp. Before that would have simply moved the nozzle about a bunch.

I designed some tower alignment clamps but they are only intended for use with the Onyx and EZStruder dismounted. I have a backburner project to move the threaded rods outside the print radius, so that the clamps can be left installed with the bed and extruder. This would help alignment, and add some rigidity to the structure.

My machine was ordered pre-Onyx so that's not a big problem and I have moved my Steve's extruder up above the top plate. Any idea on the impact of these?

I also had the idea to take the Onyx's wooden standoff and mill a new version that extends all the way out to the towers and wraps around them, helping to hold them in place.

I was thinking along the same lines and with another piece across the top that could tie the towers together up there and double as a mounting platform for the filament spool (kinda like the ones sold at tricklaser with a spool attachment integrated). But I didn't want to go waste school money on acrylic if the rigidity of the frame isn't my problem.

MSU, this image caught my eye. you have the zero lash straps up so high that it could have a direct impact on the arm length. do you notice a difference if you were to move the straps down to this distance [img]http://www.tricklaser.com/images/136929 ... 81593.jpeg[/img]

[Flateric]

I have made some progress for this issue, it may or may not apply to your machine however. The towers each have a square spacer at the top that fits between the two bearing retainers. They are made of wood of course and they have a small screw through their centers that hold the top plate up and also serve to secure the towers in place to this top plate.

I have replaced the wooden ones with printed PLA solid parts that are also much thicker and wider. I also use larger bolts to secure the plate to them. Seems to have the effect of making the entire structure more "solid".

I also have tied all three towers toegether with one very large zip tie in a big circle effectively pulling them all towards each other and holding their position to the top plate inwards with a constant force.

Before this if I gripped two of the towers halfway up the aluminium extrusion and gently tried twisting the entire structure I could observer some movement. Now there appears to be far less.

A minor tweak and far from a solution but may help give you a little better results for the time being. I would guess that the tricklaser parts that have additional cross members up top do not suffer from this problem nearly as much.