WTB: PRS Belt Drive Adapters Or 3D/2D Drawing

[PaulWall]

Long story short is I'm wanting to slowly piece together a new Centroid Acorn controller system for my PRS 2008 4' x 8' for use with the stock motors, with the eventual plan of upgrading the motors to after market steppers or clearpaths.

I don't want to invest in locked ratio planetary gear reducers, and with my budgetary constraints I'd like to use a belt drive adapters.

I know a few designs have floated around but I'm unable to find the source drawings for them if they were ever shared publicly.

That said, does anyone have a set of belt drive adapters they would sell, or the corresponding drawings for sale?

Thanks!
Paul

[Gary Campbell]

Paul...
Good luck with your system. There are a lot of SB'ers on the Acorn forum that will assist you in the process.

You may want to rethink the belt vs. planetary choice. I used to sell them, (close to 100) but as component prices rose, gearbox prices have come down. Currently, gearboxes for most systems can be purchased for around the same $$ as the components to build a belt reduction system. And the components still have to be machined. Add to that, the fact that few router machines can cut "press fit" bearing recess's well, the outsourced machining costs tip the scale towards gearboxes on price. Reliability and maintenance are both better with gears too.

By the way, I mfgr adapters for stepper and servo gearboxes to both PRT and PRS models

[srwtlc]

I agree with Gary. I'm just past my first year with my Centroid Acorn conversion and I'm telling ya, it's a whole new machine! I went with the 5:1 planetary gear boxes with closed-loop NEMA 23 motors. Yup, not a typo, NEMA 23's. Best bang for the budget buck. They along with the gear boxes and the Acorn controller will run circles around the old PRS Alpha controller/motors all day long and do it with better resolution, same or even more torque, same feed/rapid rate, closed-loop, and the best most awesome feature of all is a missing feature....not one comm error in over a year!

Running circles.

[PaulWall]

Hey thanks guys! Gary, I've bugged you enough as it is over methods of approach here ha. The message is clear, gearboxes is the way to go.

Scott & Gary - With keeping expenses down but gearboxes being preferred here, do either of you have any experience with the cheap Chinese eBay gearbox alternatives over the top shelf ultra-low backlash units? I won't be cutting micro 3D reliefs anytime in the foreseeable future, but would like a motion system that lasts a few years.

Admins feel free to move me to a different forum page!

[Gary Campbell]

I have purchased, tested and returned a half dozen sets of eBay gearboxes. Most are junk as they have lots of backlash. You may find some that are better.

The NEMA23 planetary's that Scott has are about 1/2 the price of the SureGear (my favorite) NEMA34 units and have no perceivable backlash. They can be mated to NEMA23 steppers, closed loop steppers, ClearPath Servos and 400w AC servos, all of which offer performance at or above any SB OEM system. He can tell you if after a year of commercial, close to full time use, if backlash has increased. (even tho I know the answer

[tomkbud]

I did a retrofit to my circa 2016 SB Buddy PRS Alpha 48x48x12" 4 axis machine using the Acorn board, Clearpath motors, SureGear 5:1 boxes (XYZ, Shimpo 15:1 on A), and the performance and reliability boost is fantastic. I did it all myself and, although it took a lot of time, was fairly straight forward and works perfectly. I also added an aluminum slot table (8020 type 15 extrusions), and a vacuum table configuration (Blackbox Hurricane and table mod a la A. Coholic). I've added some pics.
Tom

sb machine.jpg
sb vac.jpg
sb cabint.jpg
sb xmot.jpg