Guest
Show Posts
1
General Mach Discussion / N00b - DRO innacurate / calibration
« on: April 05, 2020, 06:18:43 PM »
Hey, I'm new to CNC and the forum. I have a 2030/3040 CNC router hooked up to an old pc tower with windows XP. My business partner purchased this little setup in a job lot on eBay and there is a bunch of extra boards and stepper motors in a box, I have no idea what any of it is so I will probably be asking questions about all of that at a later stage. The lot has been sat in the workshop for years, we never touched it and said partner left the business last year. What with the current lockdown situation I figured it would be great fun to get this little machine up and running 
The learning curve has been steep! I have never had anything to with CNC until last week, I am a TIG welder. Never heard of Mach3 and I've got a basic level of CAD experience. So, I have managed to get up to speed with CAM in Fusion, created g-code, run it through Mach and I now have an engraving of my logo in a piece of ply. I was pretty chuffed with myself to be fair. But it hasn't been without trouble, I've pulled what little hair still grows on my head more than once over.
Right now my problem is with the axis' being inaccurate. Just to re-iterate, the CNC is the bog-standard cheapo thing off eBay, the controller is a "T-D 3 axis controller" with the JP-328C board, Windows XP.
So I have gone through the calibration and got my steps per kinda sorted etc. The numbers there are:
G's - 0.00509. Pulse. 5 Dir - 1
x- Steps - 398.5. Vel - 1000. Acc - 50.
y- 540 - 1000 - 50
z- cannot get it anywhere near
Basically it won't stay accurate. I run my programme and at the end when it goes back to zero it's in a completely different place and most of the time it hits the stop and the motor freaks out. If I lay a ruler on the x-axis and run up and down the bed, each time it loses or gains a few mm. Same on the Y and the Z is just all over the place.
I have no idea what it could be and I can't seem to return any results on my searches... Please help.
The learning curve has been steep! I have never had anything to with CNC until last week, I am a TIG welder. Never heard of Mach3 and I've got a basic level of CAD experience. So, I have managed to get up to speed with CAM in Fusion, created g-code, run it through Mach and I now have an engraving of my logo in a piece of ply. I was pretty chuffed with myself to be fair. But it hasn't been without trouble, I've pulled what little hair still grows on my head more than once over.
Right now my problem is with the axis' being inaccurate. Just to re-iterate, the CNC is the bog-standard cheapo thing off eBay, the controller is a "T-D 3 axis controller" with the JP-328C board, Windows XP.
So I have gone through the calibration and got my steps per kinda sorted etc. The numbers there are:
G's - 0.00509. Pulse. 5 Dir - 1
x- Steps - 398.5. Vel - 1000. Acc - 50.
y- 540 - 1000 - 50
z- cannot get it anywhere near
Basically it won't stay accurate. I run my programme and at the end when it goes back to zero it's in a completely different place and most of the time it hits the stop and the motor freaks out. If I lay a ruler on the x-axis and run up and down the bed, each time it loses or gains a few mm. Same on the Y and the Z is just all over the place.
I have no idea what it could be and I can't seem to return any results on my searches... Please help.