Centroid Community CNC Support Forum

I just got my acorn controller that I want to control an older PRS shopbot with Gecko Drivers. I have been reading a lot and think I am up to it. I got the breakout board also. I will be asking a lot of questions so I hope you will put up with some stupid questions.

hello.
good answers require good info, start with making a google photos photo album so we can 'see' your machine/setup etc..
here is how.
https://centroidcncforum.com/viewtopic.php?f=60&t=1043

Sorry for not getting back but I was gone and haven't had a chance to work with the acorn. Right now I am gathering up the parts to get it setup.

Due to the high inductance of SB's OEM Oriental motors (PK Series) you will have to use Gecko drives to run them. If you have one of the 4G boards you can reuse the existing drives. You should check to see how much backlash those old gearmotors have as they are known for being a bit sloppy.

Centroid has schematics for most Gecko drives that you can follow and there are a number of users here on the forum that have followed that same path. There are also a number of build threads and success stories from users that upgraded from SB3 control.

If you do find that your gearmotors have too much slop and want to upgrade to modern motors and drives I sell adapter plates, 5:1 planetary gearboxes and pinion gears that fit the later model PRT rack gears (1/2" wide) and all PRS models.

Good luck with your build!

Thanks Gary I do have an extra set of Gecko 203v drives from an old 4g board hooked up now. I have the board set up on a table to check out the works. Right now I get all 3 axis but the software is not saving the pairing setting after I test it. both X steppers turn when I use the X button but when I home it the pairing changes back to no. I know you used to sell the conversion and was wondering if you had a copy of the CNC12 with the Macros and settings for my machine. My email is teriseluke@gmail.com

install pro license. axis pairing is a Pro Router/Mill feature

luke wrote: ↑Mon Feb 06, 2023 5:34 pm Thanks Gary I do have an extra set of Gecko 203v drives from an old 4g board hooked up now. I have the board set up on a table to check out the works. Right now I get all 3 axis but the software is not saving the pairing setting after I test it. both X steppers turn when I use the X button but when I home it the pairing changes back to no. I know you used to sell the conversion and was wondering if you had a copy of the CNC12 with the Macros and settings for my machine. My email is teriseluke@gmail.com

Luke...
The stepper based setups that I used to sell are now being produced by Scott Worden. Unfortunately none of those controllers used the same drives, motors or gearbox ratios as the OEM SB products, so our settings would do more harm than good if put on your control.

I have everything hooked up on a test bed with just the Gecko and steppers. I have run a test file and it seems to run smooth. What I need now is the values and the VFD speed hook up. I have a Yaskawa V7-4X vfd Here are my Shopbot values

Sadly, the steps per rev on Gecko drives is locked at 2000, so you would enter that into the "steps per rev" box

Use the chart below to determine your "turns per inch" setting for each axis based on what gearboxes you have and the tooth count of the pinions. Note that with 3.6 gearmotors and a 25 tooth pinion your turns per inch range will be less than 1 which is contrary to Centroid recommendations. If that is the combination that you have, I recommend replacing the 25T versions with 20T.
The connections below are for the GCnC Spindle harness, but it will give you the connections you need and parameters to program for software on/off and speed control

Thank you for the info going to try it on the shopbot sometime this week