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harryball
09-01-2006, 04:18 PM
I have a few questions so far... some I'm sure are very newbie.

When I run the simulation in the control software, the cut runs are very very fast. Is there a way to set the simulation to run at real speed?

I created a cut file for a 1/2" sheet of plywood. I didn't intend on it, but in the simulation the tool it cutting from 0 (board surface) to a depth of .4875" and it's taking 4 or 5 passes. How do I control the number of passes to complete a cut?

Whenever I go to cut a file, by default in the Part file execute, Plunge from 0 is set to off. How do I default this to on so the tool will cut each time?

Is there a chart somewhere of suggested bit sizes, material thickness/type, number of passes and cutting speeds?

How do I control the spindle speed from software? So far I'm using the arrow keys on the VFD and setting the speed which I'm also not quite clear on... see next question.

What is the math for spindle speed on the VFD? I was told it was 60 x the number on the box. But that doesn't seem right. It's currently set at 20 and 20x60 = 1200 that's low for RPM but if I go x60 seconds to a minute... 72000 RPM... that seems too high. I'm running a single phase 4HP HSD Spindle.

I'm sure more Q's to come.

Thanks,
Robert

phil_o
09-01-2006, 05:28 PM
My understanding on the VFD spindle is that the speed is proportional. Max speed on my HSD 2.2 HP is 18000 rpm. Max setting on the VFD is 300 therefore 100=6000rpm, 200=12000rpm. This matches your formula 60x100=6000rpm, 60x200=12000rpm, 60x300=18000rpm.

harryball
09-01-2006, 06:41 PM
Yeah, you're right... I'm seeing 180, not 18, looking at it upside down got the decimal in the wrong place. So I'm running at 10,800 RPM right now.

scott_smith
09-01-2006, 07:15 PM
No there is not a chart for speeds, bits, and materials other than some from bit manufactures like Onsrud that are not practical to us using a PRT with a PC router. It seems to be something we all need to figure out on our own.

There is a nice chip load calculator that someone made a wile ago search the forum for “chip load”.

I use mostly 3/8 cutters to profile parts. It seems to be a nice compromise between ¼ and ½.

As for the number of passes:
When you select the tool in Part Wizard click edit and look at the stepdown box.

phil_o
09-02-2006, 08:27 AM
In the SB control software under the TOOLS menu the last item is a Chipload Calculator.

beacon14
09-02-2006, 08:40 AM
If you are making part files in PartWizard you won't need to "plunge from 0" as the toolpath will be referenced from the either the top of the material or the table, depending on how your model is set up.

Plunge from 0 only works if you also set a plunge distance per rep and number of reps, and is usually used when there are no Z moves in the file - this is all handled automatically in PartWizard using the Stepdown parameter as Scott mentioned above.