Mach 3 question

[T.R.MacMunn]

Someone told me there are some Mach3 gurus on here.
Can I switch from Exact Stop to Constant Velocity in the middle of a cut?
I'm routing a bitmap ( excruciatingly slow) but there's raised lettering in the middle & I know "constant velocity " is going to round off corner or two.
I can sandblast a square foot every minute but I'm around 4 hours per sq.' routing it.
I don't care to just do a clean-up profile because I want to fool people into thinking it's cedar.

Thanks

[Greolt]

Program G61 to put the machining system into exact stop mode, or G64 for constant velocity mode.

Greolt

[T.R.MacMunn]

Thanks Greolt.
There are some options on Constant Velocity that I never noticed before. I made some adjustments there & ( insert Snoopy dance here) I'm a very happy camper.
7hrs & 16min down to 31 minutes. Yabbadabbadoo!

[jimwill2]

Rodger, that's what we want... Happy Campers!!! Had a great time in Columbia at McGrew's!

[fretsman68]

Thanks Greolt.
There are some options on Constant Velocity that I never noticed before. I made some adjustments there & ( insert Snoopy dance here) I'm a very happy camper.
7hrs & 16min down to 31 minutes. Yabbadabbadoo!

Can you please share what you did so that we may learn as well?

That's quite a substantial difference so I'd love to see the job and how and what you adjusted to get that.

Thanks!
Dave

[T.R.MacMunn]

In Mach 3, open Config, then the General Config box. Check "constant velocity" . In the lower right, there's a box CV Control.

I set CV Distance Tolerance at 100 units ...... I have no idea what a unit is.
I set Stop CV on angles over.... to 35.

Worked spiffy, although the bit caught corners on the raised lettering, but only on square corners. I think this will just require fine tuning.
When I get a chance, I'm going to make a new file, much smaller, to try different options on.

BTW, the smaller stepover added an hour to my time on the 2nd sample, but it's still one fifth the time of doing it in exact stop.

[fretsman68]

Interesting, so basically this is a trial and error type of thing, and more to the point, it's very machine and type of work specific, correct?

In other words, depending on the job, you would tweak these settings to get the optimal result? It would not just remain at a certain setting for all jobs/machines?

Thanks again-
Dave

[T.R.MacMunn]

Dave, I'm hoping to find a "sweet spot", although just knowing what each adjustment will do is a good thing.
It's like stepover ....... you don't always want the same.

[fretsman68]

Understood, and thanks for your time-

Dave

[kak]

Here is the explanation:
http://www.machsupport.com/docs/Mach3_CVSettings_v2.pdf