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kcress
Posts: 13
Joined: Mon Jan 26, 2009 12:12 am

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Post by kcress »

Hi,

So I now have a system for text generation, thanks to you folks, that works great. But.

Always a 'but'. :)

I'm having some routing artifacts that I'm only guessing about their causes. I know a lot of you have way more experience in this stuff than I and can probably tell me what's causing these two problems at a glance.

Image

Image

Notice The 'BL' is low.
The 'R' is low.
and the 'c' is sized like a lower case one and it's not.

This is a servo driven router not a stepper running Mach3.

Thoughts?
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Les Newell
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Posts: 3668
Joined: Thu May 11, 2006 8:12 pm

Post by Les Newell »

Does it look correct in Mach? If so you are losing position somehow. What drives are you using? I have experienced lost steps with Gecko drives if they are pushed too hard. Try reducing your acceleration and see if it makes any difference.

Another possibility is electrical noise. Be very careful with your grounding. In your control cabinet ground everything to one central point. Ferrite rings on the motor cables can help a lot as well.
kcress
Posts: 13
Joined: Mon Jan 26, 2009 12:12 am

Post by kcress »

Hi Les,

Thanks for the ideas. I'm pretty sure they're Gecko 320's.

I've been running an accel of 19.97in/sec/sec on the misbehaving Y axis. I reduced it to 15in/sec/sec with no improvement. Then to 13 then to 10 then to 5. At five the "BL" offset went away but the upper two thirds of an "H" disappeared. sigh.

I suspect it's not noise as it's so repeatable and the layout is clean with short wires and a shielded printer cable.

Oh yeah, it looks fine in SheetCam and in Mach3, which I just installed as part of the troubleshooting after using Mach2 for years - which never showed anything correctly on the screen..

Today I'll change the pulse width timing and see what happens. I think it's the default which is a pretty fast 1us and it should probably be more like 3us I'm reading.
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