6.1.59 Problems

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David_Lelen01
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Re: 6.1.59 Problems

Post by David_Lelen01 » Fri Sep 13, 2019 11:41 am

TestShapes-OperationOvercut0.1 shows the problem, when the operation overcut is not zero and the start point is specified to be overcut 0, the leadin is not tangent.
TestShapes-OperationOvercut0 shows the leadin actually tangent to the cutpath, regardless of the start point setting.

Start point in question is the outside path in the lower right corner.

My guess is its a rounding error somewhere. I dont know what else could cause that. I could be totally wrong though.
Attachments
TestShapes-OperationOvercut0.job
(84.98 KiB) Downloaded 10 times
TestShapes-OperationOvercut0.1.job
(84.98 KiB) Downloaded 11 times

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Les Newell
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Re: 6.1.59 Problems

Post by Les Newell » Fri Sep 13, 2019 12:30 pm

That is deliberate. A tangent leadin makes more sense than a perpendicular one when you are on an outside corner with no overcut. With a perpendicular leadin the machine has to make a sharp change in direction at the end of the lead, which slows down cutting and can affect cut quality. Instead it uses a tangent as this takes up no more space and it should result in a better cut. Does this cause a problem for you?

David_Lelen01
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Re: 6.1.59 Problems

Post by David_Lelen01 » Fri Sep 13, 2019 2:25 pm

I dont think we are talking about the same thing here... In the TestShapes-OperationOvercut0.1 file, the leadin is not tangent to the path. That is the problem.
with overcut.JPG
with overcut.JPG (58.12 KiB) Viewed 270 times

In the TestShapes-OperationOvercut0 file, the leadin is tangent to the path as it should be.
without overcut.JPG
without overcut.JPG (47.79 KiB) Viewed 270 times

If i change the leadin to perpendicular, the path is tangent, but it has the step offset and the slow down you are talking about.
with perpendicular.JPG
with perpendicular.JPG (74.44 KiB) Viewed 268 times

Is it showing up differently on your system?

LesNewell
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Re: 6.1.59 Problems

Post by LesNewell » Fri Sep 13, 2019 3:03 pm

I now see what you mean. Yes, that is a bug and it will be fixed in the next release.

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Re: 6.1.59 Problems

Post by David_Lelen01 » Fri Sep 13, 2019 8:14 pm

Ok, thanks Les! Sorry for the confusion.

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Re: 6.1.59 Problems

Post by David_Lelen01 » Mon Nov 11, 2019 9:26 pm

Hey Les,

Still having an issue with the leadins. You fixed the problem i described before, but now i have noticed if i set the overcut negative (in order to place a small tab to prevent the part from falling and jamming sideways and the machine head ramming into the part on a rapid move) the tangent leadin is still not tangent to the corner.

These tabs are absolutely critical on some parts, this machine rapids at 2,000in/min. It hit a part that got sideways a few weeks ago and actually shifted a 4ft x 10ft sheet of 1/2" steel plate about 2 inches when it hit. How it didnt break the machine, we have no clue. Since then, i have started using this 0.020" negative overcut and its just enough to work perfectly.

See attached screenshot.

Thanks,
David
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Sheetcam Leadin Issue.PNG
Sheetcam Leadin Issue.PNG (126.91 KiB) Viewed 175 times

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Les Newell
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Re: 6.1.59 Problems

Post by Les Newell » Tue Nov 12, 2019 10:41 am

That is technically correct, even though it is not what you want. I'll see what I can do.

I'm a little surprised your machine doesn't have a breakaway on the head so if you have a crash like that something cheap lets go and protects the expensive parts. Tip-ups are a nasty fact of life with plasma, waterjet and laser cutters. For instance on plasmas it is not uncommon to use a magnetic or spring mount for the torch. In the event of a crash the mount lets go, saving the torch. I've also seen plastic bolts used to protect machines. The bolts are strong enough for normal operation but in a crash they snap or strip out.

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Les Newell
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Re: 6.1.59 Problems

Post by Les Newell » Tue Nov 12, 2019 11:56 am

Well, that was easy enough. A new release is uploading now.

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Les Newell
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Re: 6.1.59 Problems

Post by Les Newell » Tue Nov 12, 2019 12:04 pm

Oops - That last upload included some experimental code so I pulled it. It may be a week or so before I can get that experimental code working.

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Re: 6.1.59 Problems

Post by David_Lelen01 » Tue Nov 12, 2019 12:10 pm

Awesome!! Thanks! No problem to wait for it, not an urgent need, just a improvement.

The head of the machine is magnetically attached to the machine axes and it did knock it off very easily. Usually it will hit a part right as the rapid starts and before the travel is up to full speed, but this part was several inches away and the operator didnt see it. The travel was already full steam ahead when she hit.

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Les Newell
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Re: 6.1.59 Problems

Post by Les Newell » Tue Nov 12, 2019 12:17 pm

Wow, even then it managed to move a sheet of 1.2" steel? That's scary!

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