LinuxCNC angular axis and inverse timing

Thanks for the try! Its just the first few lines that look like that because the first layers are mostly featureless. When it gets to the multi-axis moves I'm sure it will get crazier. I just used those lines to highlight my problem.

I have an email out to ask if DeskProto can extend the JavaScript engine to be a post processor. Right now DeskProto automates a lot of features with the scripting engine just not the post processor.

Till then, I'm stuck in 3 axis only! Sad but I'll live!

Yes, I am running the DeskProto 6.1 Beta, no, can't tell it to put angular movements on separate lines. I dug for config files to help and couldn't see any that would effect this.

I'm pretty much SOL but the guy from DeskProto made a great point and it is surprising to me there isn't a tool already written. I will write a tool I guess to make this conversion. It will take time and my CNC will have to remain motionless while I make this tool... oh well! Hopefully the end result is this will never be a problem for anyone again!

andypugh wrote:

However…
It seems that you can run the Beta in a VM. I have to say that I am quite impressed with the software itself.
Have you tried altering the "factor" of the A axis in the "movement" tab of the postprocessor? If you set that correctly for the approximate diameter you are working at, then you may be able to increase the cutting speed to the right value.

There is no doubt the guy writing DeskProto is talented. Even with my trouble using the A axis I would still recommend his program for 3 axis milling. Some of the cuts I've done with an 1/8" ball nose end mill came out with more detail than another more expensive package did using a 1/16" ball nose.

I haven't played with the "factor" for the A axis yet. Another fix is to set the Axis to machine at one slow (but way faster that the command tell it) speed. I ran it like that for a few minutes but I just couldn't keep it set like that. It would be like buying a race car and driving it around in first gear.

I'm actually finished with the g-code parser for my tool to convert the files to work with LinuxCNC. It really wasn't all that hard. I'm thinking about making the rules and processors JavaScript (by default) or whatever scripting engine you want so that way others can tweak without getting dirty. Then, if you don't like JavaScript you can bang it out in whatever language you feel comfy with.

Actually, I didn't catch it at first but I run Rhino and DeskProto in a VMware instance under Winders 8.1 beta on my Ubuntu 13 machines and never have had a problem.

OK, so first blush at turning the "inches per minute" into "degrees per minute" is below. What I did is used the Z axis to figure out the surface speed as the program was originally written and turned that into degrees per minute;


With Z1.4500

Original:

Converted:

What is scary is as the cuts get deeper the degrees per inch rises to account for less surface;

Original:

Converted:

Even though that number, 4225.4 degrees per minute sounds huge, its only 11.74 RPM which is admittedly still too fast! That's running full tilt on my A axis though so its doable but still scary to see and hear.

Anything sound out of place with this theory?

Also, does anyone have a good, short example of a inverse timing 4 axis g-code? i want something to compare to the is known to work.