2in Cyl becomes Square, 10in Cyl becomes Decagon.

Discussion of tinyG control platform
Post Reply
SniperTeamTango
Posts: 19
Joined: Sun Jun 22, 2014 12:15 am
Location: Niagara Ontario Canada
Contact:

2in Cyl becomes Square, 10in Cyl becomes Decagon.

Post by SniperTeamTango » Wed Sep 24, 2014 12:57 am

http://camforum.autodesk.com/index.php?topic=5400.0
TLDR: Arc codes do weird crap.

I'm trying to use Inventor HSM 2015 (full version) for GCODE production because makercam isn't cutting it and meshcam costs a lot. (I know inventor does too but I already have had it for years and just get the upgrades now that Im in school again)

The part I originally tried making was the back of a dust shoe for my spindle, but the machine merely milled a slot into the material. So I exported a 2in cyl from makercam and from HSM. the 2in cyl draws a circle (I took out my tool at this point, funds running low, no need to burn material), but the inventor part draws a square at 45°from either axis. I tried this with the Fanuc processor (A gcode standard), a tinyG processor, and a grbl processor. Later when trying the grbl processor, I tried a 10" cylinder, and it drew a decagon.

I officially am lost. Camforum says its the board, I dont know if I agree with them since Ive updated the firmware to fix tgfx issues and now my machine *was* running amazingly from makercam.

Enclosed are the NC files, and TGFX screenshots.
Attachments
TGFX Screenshot.png
Makercam 2in vs Inventor 2in
TGFX Screenshot.png (455.57 KiB) Viewed 1143 times
TGFX Screenshot Two.png
Decagon?
TGFX Screenshot Two.png (437.28 KiB) Viewed 1143 times
Gcode Files.zip
Zip file containing the Gcode files (.nc) and the two tgfx screenshots.
(3.03 KiB) Downloaded 47 times

SniperTeamTango
Posts: 19
Joined: Sun Jun 22, 2014 12:15 am
Location: Niagara Ontario Canada
Contact:

Re: 2in Cyl becomes Square, 10in Cyl becomes Decagon.

Post by SniperTeamTango » Thu Sep 25, 2014 3:31 pm

Bump

trying to get this fixed and get back into production.

criznach
Posts: 220
Joined: Sat Dec 14, 2013 5:28 pm
Location: Great Falls, Montana, USA

Re: 2in Cyl becomes Square, 10in Cyl becomes Decagon.

Post by criznach » Thu Sep 25, 2014 5:07 pm

I don't have a tinyG but I looked at your file in a gcode viewer and the circ file looks round. Just a guess, but I'd investigate the Arc segment length and Segment timing (interpolation interval) settings. The problem looks like your arc commands are being divided into too few line segments to make a smooth circle. Since the gcode looks good, I'd assume it's the controller. Those two settings look like they may control arc division.

aldenhart
Posts: 132
Joined: Tue Apr 10, 2012 2:17 pm

Re: 2in Cyl becomes Square, 10in Cyl becomes Decagon.

Post by aldenhart » Sat Sep 27, 2014 1:22 am

What is your setting for chordal tolerance $ct? It should be about 0.1mm

SniperTeamTango
Posts: 19
Joined: Sun Jun 22, 2014 12:15 am
Location: Niagara Ontario Canada
Contact:

Re: 2in Cyl becomes Square, 10in Cyl becomes Decagon.

Post by SniperTeamTango » Sat Sep 27, 2014 1:40 am

aldenhart wrote:What is your setting for chordal tolerance $ct? It should be about 0.1mm
This was it, fixed it last night. It was around 6.5mm (and I have no idea how it got there)

I basically went down the list of $ things and made sure everything was default other than my axis settings.

Works great now, time to clock it up!

Post Reply