@Joe_Spanier did you go with the ones that are all plastic? Or the ones with the aluminum outer housing?
The PBC linear bearing I used are all aluminum with a Teflon hybrid inner coating (trade named Frelon). They are smooth as butter going straight. But the sideload from a corexy belt turning 90deg to the x carriage for the extruder causes tiny micro chatter at changes in direction.
It’s funny. Everything in straight lines is perfect to .1mm or better. My only problem is circles. At first I thought in might be issues with marlin coordinate transform from corexy to Cartesian. But no one else seems to indicate that problem on thief corexy.
Mine where straight plastic sleeves. I can probably dig around and find the part numbers. Im going to try the acetal bearings from spd-si like @Tim_Rastall is using in his platform for this. Ill let you know how it goes. Im just using drill rod for my shafts
@Joe_Spanier
actually, I’m using the sintered bronze versions as they are harder wearing than acetal ones but then I’m using induction hardened shaft too :). The coated shafts and igus bushings will be super smooth but those shafts ain’t cheap.
Nope I meant the shafts. I used half inch because I found them through surplus resellers. Ried supply for the shafts, link above. Looks like they are out of stock right now.
@Eclsnowman , check out http://3dprinterhell.blogspot.com/?m=1
He did a lot of work with spectra and core xy and had issues with tensioning. He also had posts on the reprap forums and then his progress just vanished. Not sure if he ever got it working
@Eclsnowman is the move to gt3 (which I never knew existed) to further reduce any backlash? Are your belts actually flexing more than your frame? Just curious, one of these days I will eventually compete my design… when work settles down (it’ll never settle down, ugh)