Centroid Community CNC Support Forum

Bought my Acorn board a few months ago and finally had the time to start setting it up but have run into an issue where I can't move the axis. The motors don't lock into place as I can turn them by hand. I when through the whole video step by step and followed this diagram https://www.centroidcnc.com/dealersuppo ... 980.r3.pdf

after that didn't work I hooked it up just like the video described it with the 24 V input just incase that was needed but still nothing.

I have attached pictures and the report down below. Any help will be appreciated Thank you

I am assuming that your control failed. That is usually the result of a failure in the Testra "box" (shown circled below). You need to remove the Testra and wire your motors, limit switches and estop into the Acorn to replace it.

OR: viewtopic.php?t=10476

the schematic you posted is for a G540 drive wired in legacy configuration (not recommended)
do you have a G540?

what drives are you using?

I think the testra is power supply, stepper drives, and other inputs all in one similar to a G540. So basically you are hooking up a controller to a controller. I would not do that. Get you a power supply and some stepper drivers to replace the testra and build it from scratch.

IronCaliber wrote: ↑Fri Apr 25, 2025 6:46 pm Bought my Acorn board a few months ago and finally had the time to start setting it up but have run into an issue where I can't move the axis. The motors don't lock into place as I can turn them by hand. I when through the whole video step by step and followed this diagram https://www.centroidcnc.com/dealersuppo ... 980.r3.pdf

after that didn't work I hooked it up just like the video described it with the 24 V input just incase that was needed but still nothing.

I have attached pictures and the report down below. Any help will be appreciated Thank you

i would put new closed loop units on this machine, they run so much better and they are cheap. big performance upgrade per dollar
https://amzn.to/42yPrKV

and here is how to hook up.
https://www.centroidcnc.com/dealersuppo ... 265.r2.pdf

cnckeith wrote: ↑Mon Apr 28, 2025 2:10 pm the schematic you posted is for a G540 drive wired in legacy configuration (not recommended)
do you have a G540?

what drives are you using?

I do not have have a G540. When I first called Centroid a couple months ago they told me to use that diagram to wire up my CNC. I was not told that it was not recommended I attached a picture of the Router drive below.

Ken Rychlik wrote: ↑Mon Apr 28, 2025 2:21 pm I think the testra is power supply, stepper drives, and other inputs all in one similar to a G540. So basically you are hooking up a controller to a controller. I would not do that. Get you a power supply and some stepper drivers to replace the testra and build it from scratch.

Gary Campbell wrote: ↑Sat Apr 26, 2025 8:47 am I am assuming that your control failed. That is usually the result of a failure in the Testra "box" (shown circled below). You need to remove the Testra and wire your motors, limit switches and estop into the Acorn to replace it.

OR: viewtopic.php?t=10476

Testra.PNG

Is there any way to test it to confirm the Testra box is the issue?

its possible you could get the testra box turning motors.
do you know if it works?
do you know the pin out that it uses on the DB-25?
the Acorn defaults to the G540 pin out. If the testra box if different then you have to change it using the Wizard db25 pin out assignment page.
do you have a link to the testra manual?

what i meant to say is i don't recommend using the g540 in legacy mode (which means using the i.o running thru it, since acorn has its own its, it is a simple matter to use the Acorn i/o instead of having it run thru the g540 or any other device. its just not necessary and adds complication and potential issues. you can use a g540 in DRIVE ONLY mode, just like any other drive. i would suspect the testra is similar in that you might be able to use it as a stepper drive and keep the i/o out of it. (home switches for example)

either way with new motors and drives that are way better (and cheap) than the open loop testra setup the recommendation is to use new motors and drives that are well documented and easy to get running. or you can figure out the testra if you think it still works.

I have not seen it work, the CNC PC that came with it was dead so I decided to switch it to Centroid to get it to work. The previous owner used it for a few years and then got stored away for 8+ years and then donated it to a church that just wanted to get rid of it.
I'll look into the pinouts for the DB-25 and see if I can at least get it to move.

I read up into the differences of closed and open looped systems and definitely want to upgrade it to closed loop now. I'll still try to get it to move with the DB-25 but if not I'll pick up these motors. couple questions though

Will these be a pretty much drop in replacement when it comes to mounting them on to the machine?

The CNC needs an air assist to lift the router head, will I still need it with this new motor?

Just my 2 cents but I would not waste any of my valuable time trying to get the old controller to work. It’s old, outdated and not worth the effort. Buy the closed loop stepper system you want. The biggest concern is getting a closed loop drive system whose motors are a direct bolt on if you don’t have the ability to machine adaptor plates for larger motors. Also, motor shaft size must remain the same if you plan on using the same gears, pulleys or couplings. I don’t know how that machine moves but you have one of those on the motor shaft.

Is there a “bolt on replacement” like you ask? Yes, but you’ll have to do your homework to find it. It won’t be that hard to do. Research the motors that are on the machine and find its mechanical specs. Bolt pattern, shaft size, etc and match those to a new motor. I’m guessing that’s a 60 mm NEMA 23 or 24 motor frame from the part number.

As for the PC that came with it, it’s old junk also so recycle it too. Make sure you get a PC (not a laptop) that meets the minimum requirements to run CNC12.