Slow Cornering

[Keith Larrett]

I was cutting cabinet parts yesterday using the eCabinets ShopBot Link. The machine was coming to a stop at corners. Like it was thinking about what to do next. Going down the straights it was cutting at normal speeds (270 ipm or 4.5 ips), but when it came to a corner it would stop before continuing. Also, when cutting out a bunch of fixed shelves with tenons, it was going around the corners of the tenons painfully slow.

I know I didn't change any of the settings in the eCabinets ShopBot Link. Is it possible some settings got changed in the SB3 software? If so, which ones and what can I do to restore them?

I'm concerned about burning bits/plywood. Any help or advice would be greatly appreciated! Thanks!

I shot a short video with my phone showing the problem:

[Tim Lucas]

Keith

Check out one of Brady's post about corner speed settings and see if something is set totally wrong

http://www.talkshopbot.com/forum/sho...t=corner+speed

[Keith Larrett]

Thanks Tim. On my way to the shop now. I will read the articles and check my settings. I was wondering if that was the issue. I don't see anything in the eCabinets Link that could affect the cut like that.

[Keith Larrett]

Somehow my ramp values got changed. Not sure how that happened

Anyway, the first screen shot shows the changed values and the second screen shot shows the ramp values after resetting them. I ran an air cut of one of the files I cut yesterday and it seems to be cutting normally. I guess the main culprit was the XY Move Ramp Speed being set to 0.1 instead of 0,4

Thanks again for pointing me in the right direction Tim!

If anyone has any tips for tweaking these values, aside from the valuable information in Brady's post, I'd be interested in learning more. I'm primarily cutting sheet goods for cabinet parts. It seems a lot of the info on tweaking these values is geared towards cutting intricate parts, 3D etc

[GeneMpls]

I can't help, Keith, but I'm wondering what the air cylinder (?) on the Z is or does? Thanks Gene

[Keith Larrett]

I can't help, Keith, but I'm wondering what the air cylinder (?) on the Z is or does? Thanks Gene

Gene. I have an ATC. The air hoses you see open and close the gate at the back of the dust skirt so the machine can back up to the tool holders to change tools. There is also air on the Z for a couple other things. The Z-axis has a pneumatic assist, the spindle is air cooled and there is a pneumatic draw bar in the spindle to hold the tools.

[Tim Lucas]

Keith

Brady has a article that breaks down the whole thing but I can not find it

Hopefully Brady will chime in with a link to it again

Tim

[Keith Larrett]

Is this the one you were thinking of Tim?


http://www.shopbotblog.com/2008/03/a-ramping-the-vr-command-and-how-to-tune-your-tool-for-maximum-performance/

It was in the thread that you linked to. I read it and it was very informative.

[Tim Lucas]

Yes that is it

[dlcw]

Somehow my ramp values got changed. Not sure how that happened

Anyway, the first screen shot shows the changed values and the second screen shot shows the ramp values after resetting them. I ran an air cut of one of the files I cut yesterday and it seems to be cutting normally. I guess the main culprit was the XY Move Ramp Speed being set to 0.1 instead of 0,4

Thanks again for pointing me in the right direction Tim!

If anyone has any tips for tweaking these values, aside from the valuable information in Brady's post, I'd be interested in learning more. I'm primarily cutting sheet goods for cabinet parts. It seems a lot of the info on tweaking these values is geared towards cutting intricate parts, 3D etc

I've had a perfectly working Shopbot on Friday afternoon, shut it down for the weekend, then on Monday morning values have changed, speed control for the spindle doesn't work anymore, ramp settings are all goofed up, etc.

I don't know what happens when the machine is turned off, but this is something I brace for every Monday when I enter the shop to go to work. I don't know if Shopbot control screws up the settings when it is shut down or if there are gremlins in my shop powering up my computer when I'm gone and raising havoc. I just find it irritating.