KEEVO Printer (corexy)

nuverian

Hello again,

I just wanted to share with you the last build I made, which of course uses Duet

(KEEVO = Cube in Greek)

(yeah the cables need some management)

It is also posted on Thingiverse -> https://www.thingiverse.com/thing:4129443

Any feedback is welcome of course!

Also, regarding the 3 leadscrews (which are only really mounted on the bottom), do you think that the forces from the Z belt will bend the leadscrews in the long run. I don't really see any bending though. It can be seen more clearly in this video which was the previous version (an hbot without duet and other stuff, but z axis is the same) -> https://www.youtube.com/watch?v=K0pcGKAQ4eA

Cheers

Phaedrux

@nuverian said in KEEVO Printer (corexy):

do you think that the forces from the Z belt will bend the leadscrews in the long run

Unlikely.

Nice looking printer.

nuverian

@Phaedrux Hey thanks!

Great printer you have as well Similar Z concepts. I see you use two bearings (as far as I understood). Was that for the same reason and for peace of mind?

I also don't think it will be a problem, but what I was thinking is adding a counter bearing on the bottom so that when the belt pulls, the leadscrew won't budge. Something like this mockup:

Maybe an overkill, maybe not

Phaedrux

Yes, the double bearing block was mostly to help keep the lead screw stable vertically, but also would help counter and pulling forces from the belt tensioner.

https://www.thingiverse.com/thing:2401504

A Former User

@nuverian said in KEEVO Printer (corexy):

@Phaedrux Hey thanks!

Great printer you have as well Similar Z concepts. I see you use two bearings (as far as I understood). Was that for the same reason and for peace of mind?

I also don't think it will be a problem, but what I was thinking is adding a counter bearing on the bottom so that when the belt pulls, the leadscrew won't budge. Something like this mockup:

Maybe an overkill, maybe not

Double shear is nearly always better than single shear.

mrehorstdmd

The screw is 8mm diameter and you're pulling on it with the same belt that's pulling on the 5 mm motor shaft. If it's OK to do that at the motor shaft, it's probably OK at the larger diameter lead screw.

You could easily fabricate a two-bearing mount for the lead screw as a single piece either from rectangular aluminum tubing or by printing a part with a tang that fits in the t-slot. I did this in my sand table (the brown part):

alt text

The two pieces that make up the pulley mount are aligned by bosses. The bearings press-fit tightly into the top and bottom pieces.

nuverian

Thanks for your comments.
I ended up adding a counter bearing on the bottom to help with the belt forces, as well as a collar on the leadscrew above the pillow bearing to help with vertical/gravity forces.