Had one of the Gantry wheels split in half on the GF Basic
Only noticed it because I took the Laser head off for cleaning and saw it laying in pieces
Even though I was a little out of warranty GF sent me a new one.
In the mean time I trudged thru the GF user forum and found several references, seems like this happens a lot
https://community.glowforge.com/t/broken-glowforge-rollers-a-trip-to-the-hardware-store/62632/54
A known problem it is a weak design that has little alternative but to break in two
The choice of the 12 x 6 x 4 bearing is likely not a problem but the root cause is the close placement of the wheels to the rail
The plastic roller pressed onto the bearing is about a 1/2 mm thick in the middle and so it is thinnest where the splitting forces are the greatest
While waiting for the replacement (it came very quickly) I thought I would try one of the 3D models offered in the users thread, they are not workable.
I went thru careful efforts to measure a good one and came up with a very good CAD model hear for your use
I increased the thin mid section as much as possible and made the roller a little taller because the 3D45 needed a little more material to print reliably.
I'm going to run the 3D version until it breaks.
3D Printed at the highest resolution, solid fill
For a test I made the gauge for setting dividers
Precision is right on and the straight lines show no waviness
Update!
Finally got an Optical comparator so I can truly measure the original wheel. I'll be looking into that this summer.
