Next upgrade project, several ideas

Ive got several thoughts about where to go next, after fighting a Z axis issue that loosening a few bolts fixed mostly.I’m thinking of ball screws for the Z axis, an openrail X axis, or switching to a horizontal X axis still using rods, maybe larger. I’m also experimenting with a bowden setup but my first attempt kept extruding long after the stepper stopped. I think the PTFE tube stretches, storing energy that is released when the extruder stops. I’m not sure how to address that. I can’t use much more retract because there isn’t enough cooling in the hex part of the hotend to keep from sucking mushy plastic through it. Water cooling could work, but I’d rather not have so much retract. Has anyone tried some other type of tubing for a bowden setup? Something that would also work with flexy filiment too?

I’m sure someone has thought about the X axis being much better supported on both sides of the Z rods with a horizontal arrangement. Any thoughts?

What do you guys (and the occasional girl) think about which way I should go to eliminate wobble? Right now the Z axis is by far my biggest problem but I’m going to try to brute force that with some 84 in/oz steppers, may 96. I’m willing to buy quality parts IF they lead to real improvements.

I’m also thinking real hard about adding encoders to the Z steppers, or linear endcoders on the vertical supports with sensors on top of the X ends. The more I think about it the more I like the idea. I’ve already double sided taped a ruler to the right side vertical support so I can tell if the Z axis is coming up short during printing. I have to abandon the print, but at least I know about 1/4 or the way through if issues are going to ruin it. I can write firmware upgradesto read encoders and either try to correct, or abandon a bad print.

any other ideas for improving TAZ 5 accuracy?


For the x carriage, the old ao-10x series printers actually had a horizontal x axis. The main issue with the horizontal style is it doesn’t really arrest the biggest potential x axis error as well as the vertical arrangement can. The motion transition from left to right induces a bit of a pendulum effect in the direction of travel. Having a rail above the nozzle pivot point makes it a bit more difficult for the nozzle to get out of allignment. A good accurate axis can be made either way if you engineer it right, but in my experience the over under arrangement is easiest to get right.

I’ve toyed with the idea of nozzle water cooling, but the extra mass on the x axis carriage worries me.