Machsupport Forum

G-Code, CAD, and CAM => LazyCam (Beta) => Topic started by: cpayne on December 19, 2009, 01:11:15 AM

Title: pockets messing up
Post by: cpayne on December 19, 2009, 01:11:15 AM
Hi.  I am trying to get a pocket to work.  Its a rather complex shape, but its not working at all. I have fiddles with all the settings and have had no luck.  All the radius are 1/16 and I plan on using a 1/8 endmill.   I will not create a pocket.  As shown in the blue the pocket is actually going beyond the chain and not filling into the inner island.  I tried a 1/16 end mill and it kept it inside the chain, but did only one sweep and did not fill the pocket.  I have played with the connection tollerances too.   Please help.   Screen shot attached.

Title: Re: pockets messing up
Post by: Overloaded on December 19, 2009, 09:02:47 AM
Best to provide your DXF but try this. Label your 1/8" tool as Diameter .124 in the tool description and see what you get. LCam is weird when the tool and drawing radiusses match exactly.
Just a guess,
RC
Title: Re: pockets messing up
Post by: cpayne on December 19, 2009, 11:02:39 AM
That did not work either, did not create any entities...   DXF attached
Title: Re: pockets messing up
Post by: RICH on December 19, 2009, 11:11:51 AM
There is more than one way to get the pocketing done. But attach the DXF as RC suggested.

RICH
Title: Re: pockets messing up
Post by: RICH on December 19, 2009, 11:54:48 AM
I want to look at and try try a few things with your file.
It will be later on today. Snow won't let me open the door........ so need to do a few things first before i can play.
It will pocket!

RICH
Title: Re: pockets messing up
Post by: cpayne on December 19, 2009, 12:05:36 PM
Thanks!

I tried this DXF too, same negative results.   I removed the 1/16 inside fillets that would be created by the endmil anyways to try to make it simplier. I kept the outside fillets because I need them as a relief.

I can draw in all the pockets manually, but that kinda takes the fun out of it...

Thanks!
Charlie
Title: Re: pockets messing up
Post by: Overloaded on December 19, 2009, 12:17:27 PM
Curious to see what you find Rich, this is a strange one here.
The radiusses are actually .06 (by my CAD) instead of .0625 but a .119 cutter still doesn't work as it normally would.
The first file DOES however offset AND pocket well w/Sheetcam and Vectrics.
I gotta go dig out my truck.
RC
Title: Re: pockets messing up
Post by: RICH on December 19, 2009, 03:50:04 PM
RC,
Snow.....my opinion nowdays.......WHAT GOD PUT ON THIS EARTH LET HIM TAKE IT AWAY!  ;)
So we we got the first round of snow shoveled. Some requests are not answered!  ???

You may want to increase your unit precision in CAD and  then you will see that the radius is .0625.
I will post what i did to make it work.
RICH
Title: Re: pockets messing up
Post by: Overloaded on December 19, 2009, 04:09:44 PM
Yup.....see that now, Thanks.
Never had THAT change before. Always at .0001, till now.
rc
Title: Re: pockets messing up
Post by: cpayne on December 19, 2009, 04:33:49 PM
I had drawn it with 0.63 so to try it with a slightly different fillet than the endmill to see if it had an effect.   Here is the file with the fillets in 1/16 increments, same result.  All the paths are big enough for a 1/8 endmill, which is what I drew this for.    I have been playing around with the overhang and finish with no results either, I am not sure what they do...   

Charlie
Title: Re: pockets messing up
Post by: RICH on December 19, 2009, 08:03:09 PM
Overhang is not functional. Finish is the amount of stock you want to leave for another finish pass. So you would clean out the area and then make a finish pass.

BTW This particular profile is a PITA!
RICH
Title: Re: pockets messing up
Post by: cpayne on December 19, 2009, 08:21:40 PM
Thanks.  So any idea how to make a PITA pocket?  Or are we refering to the other deffintion of Pita?
Title: Re: pockets messing up
Post by: RICH on December 19, 2009, 09:20:13 PM
cpayne,
For this PITA file just take one read of the attached file before going to bed and then
apply  the verbage  to the attached Lcam.  :D

I have seen this kind of problem when trying to do a pocket. When it dosen't work, which can be due to a whole
bunch of things, the drawing, the tool, practical machining approach, corrupted file. Sometimes it's just better to take a different approach and it will get pocketed. BTW, i tried to pocket it with a different program and it was even worse. You won't pocket something if you can't create an offset for the profile. So that is always my 2nd option after a check of the drawing.
Please note that i wanted to do this using  an 1/8" end mill. with smaller cutters it probably would have been easier i guess.

RICH
Title: Re: pockets messing up
Post by: ger21 on December 19, 2009, 09:41:20 PM
Yup.....see that now, Thanks.
Never had THAT change before. Always at .0001, till now.
rc

Decimal precision is saved in the .dxf file. So when you open it, it **should** change the settings in your CAD program as well.
Title: Re: pockets messing up
Post by: Overloaded on December 19, 2009, 10:10:11 PM
I thought that MIGHT be the case but wasn't sure.....Thanks Gerry
Title: Re: pockets messing up
Post by: cpayne on December 20, 2009, 01:59:18 PM
Well after much fiddling and what not, I decided to try to draw the pocket cuts in CAD.  I managed to get the outside and inside offsets as one continous chain.    In drawing the offsets in CAD (Solidworks) i releasized why LazyCam had trouble with it.  Just offseting the lines kept creating all sorts of illegal overbound situations, but I finally faked it inot working.   Next is to try it out and see what happens.   THe issue will be as I need to make tweaks to the design, etc I will have to manually repocket it or manipulate it so lazycam can handle it each time, both time consuming...

THanks for all the help.

Charlie