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View Full Version : Need Help! Machine Home in relation to MadCAM Model Home



subnoize
07-30-2013, 02:10 PM
Hey!

Can someone please explain where 0,0,0 is in MadCAM in relation to machine homing and what the "Home Position" parameters in the post processor screen do?

My last cut was a lot of trial and error and I would love this next cut to be spot on as a true test of a properly setup machine. To get the Z axis right last time I took the stock off the the table and watched where the cutter landed a few lines into the program and move the stock to match. Yeah, I know, noob!

Thanks for your help!

subnoize
07-30-2013, 03:34 PM
actually, i think I answered part of my own question. so the parameters for "Home Position" are not effective unless they are also in the Post Processor.

So, maybe I can take it from here...

mactec54
07-30-2013, 09:31 PM
subnoize

Your machine home has nothing to do with your Part 0.0 the ( 2 ) are totally separate, once you have homed your machine, you then set up your work X0.Y0 & your Tool zero, which is the top of your part for your tool, these settings will be saved in the control

Your work offset or X0.Y0 is what is called a G54, this G54 will be near the start of your program The Z offset is a G43 , These Tool & Part offsets are in the control

When you do your drawing in cad or cam, you will have a X0.Y0 point on your part, this is were you would set your machine to for machining

subnoize
07-30-2013, 11:26 PM
Err, thanks. I'm still getting weird misses when I touch off from the work piece. I just discovered that the values input into the offsets is persisted when LinuxCNC is shut down so I may have an old value floating around in there making me frustrated.

Thanks for helping though!

subnoize
07-31-2013, 08:49 PM
Well, second project with MadCAM in the bag I am more convinced I have to have MadCAM!

The image is my three attempts while spending more time setting up the project instead of just accepting the defaults like the first cut. MadCAM being Venus on the right.

Why Venus De Milo you ask? Hard to cut and as you can tell from the picture, easy to see which software package rocks! I'm sure everyone else can get better than I do here, but the test was how quick can I get the highest quality cut. So far MadCAM is really, really kicking butt!

I am hoping to raise the cash to invest in MadCAM here soon and I'm excited to see what happens when we get G93 (inverse timing) and cut this using 4 axis. Now, when that happens, expect a YouTube video! That will worth showing everybody, right?

So, now what I would love to hear is from you wizards telling me how to make the checkerboard pattern disappear and get a smoother finish without going too much over 2 hours.


thanks!

194192

PS. the two on the left were cut with a 1/16" Niagara Ball Nose. The MadCAM on the right was cut with a 1/8" Niagara Ball Nose. The heads are all the same size, I just tilted the camera to favor the MadCAM cut.

PSS. I was not measuring the height of the piece in Rhino correctly which is the original intent of my question. I did a measure of the green box with everything turned off and used that for the fixture coords solving my problem! Woo-Whooo!