Remixed Parametric/Adjusable Replicator1 Spool Holder with extended bearings

For 5 years, I've been using joeyC's excellent Parametric/Adjustable Replicator 1 Spool Holder ( https://www.thingiverse.com/thing:40084 ). It's given me years of reliable service with no issues. However, I've run into a problem with it recently. Some filament manufacturers (CC3D is one example) have adopted a spool width which doesn't seem to play nice with the spacing on the original spool holder. The spool will sometimes slide and get stuck between the frame and a bearing. In at least two cases, this has caused the spool to roll off the table, which does tend to get your attention at 2am.

At first, I wanted to make long, solid rollers to replace the bearings, in the hopes of alleviating the problem. Unfortunately, there really isn't a lot of clearance in the original design for that. So instead, I extended the original bearing shafts to accommodate 3 608ZZ skate bearings in a line, instead of one. This means that the spool holder requires 12 bearings instead of 4, but skate bearings are cheap and this works amazingly well.

As a side benefit, the beveled grooves which form when you push the bearings together have a tendency to redirect the spool if it wanders a bit. It seems to have tamed the issues I was having. Also, it means that I can leave it adjusted to its widest setting and accommodate all of the different spool widths that I own. In addition to the added bearings, I did round the edges of the tab on the t-shaped spool hanger to make it more easy to insert into the main body. All other aspects of the models have been left as they were in the original.

When I built the original spool holder, I printed it at 100% infill in natural PLA. In 5 years, it didn't warp or bend, so I went with 100% infill again, using Hatchbox black PLA. That seems to be the best-performing PLA on my old Replicator. I used some self-tapping screws which were liberated from an old Samsung laser printer, which worked well enough. Refer to joeyC's original Thingiverse page for hardware/assembly instructions.