Messages

11

General Mach Discussion / Re: Router cuts angles wrong

« on: June 17, 2013, 10:37:59 AM »

Many thanks, Ian.  Here's part of the problem:

X departure = 14.75 - 3.503 = 11.247
Y departure = 3.998 - .25 = 3.748
sin(x) = 3.748 / 11.247 = .3332
arcsin(.3332) = 19.46 deg.
arcTAN(.3332) = 18.4 deg.!!!!!  

Oops. I've been calculating the wrong trig function. That's embarrassing. I needed to refresh my brain on what function I was calculating before I did it. At least I can duplicate that mistake.

So the problem lies within the design chain of DesignCAD 3D Max -> .DXF file -> CamBam. -> gcode. DCad swears the angle is 38 deg.

Now all I have to do is figure out where that degree got lost. Anyone? Beuller?

Again, many thanks, Ian.

Brad

12

General Mach Discussion / Router cuts angles wrong

« on: June 16, 2013, 10:38:17 PM »

Machine is a CRP4896 with CRP NEMA 34 drives & electronics, latest Mach3, Dell optiplex running Windows XT Pro.

I was trying to rout some angled dadoes and ran into this  problem:  The dadoes are off about a degree. Picture a ">" pointing in the X+ direction, with an included angle of 38 degrees. Each side of the ">" is off by about -1  degree (the included angle comes out as 36 degrees). I trigged out the gcode and it is correct. X & Y axis are both 1272 steps/inch. It comes out the same when cut left to right or right to left, 10 IPM or 50 or 125 IPM. The machine is square and backlash in both axes is less than .005". 

The problem is consistently repeatable. It is not due to cut deflection, as it does it with a V cutter set at .025" DOC as well as a .25 endmill taking a quarter inch deep cut.

The XML file and sample Gcode are in the attached zip.

Someone please check that the gcode really produces 19 deg per side, not 18. It wouldn't be the first time I thought I did something math-y and actually did something else.   

13

General Mach Discussion / Re: Anyone have a list of New router companies that run Mach 3?

« on: February 16, 2012, 12:24:10 PM »

Mechanically, the build is going just fine. I'm having some angst getting the steppers to move. Computer? Connection? Electronics? Mach3 setup? Operator error? Haven't narrowed it down, yet.

14

General Mach Discussion / Re: Anyone have a list of New router companies that run Mach 3?

« on: February 15, 2012, 06:26:52 PM »

Also try CNC Router Parts. They offer a line of kits that are well made. I'm building one now. You can find them on CNC Zone and http://www.cncrouterparts.com/machine-kits-c-29.html

15

Mach4 General Discussion / Re: New people welcome !! Come in here and introduce your self!

« on: February 15, 2012, 05:24:20 PM »

Hi! I'm Brad, in Round Rock, Texas. I'm a newbie and an old-timer at the same time, as I programmed 2 axis NC lathes and 4 axis NC mills, back when those newfangled CNC machines were first coming out. I'm building a CNC Router Parts CRP4896 Router which I plan to use for general woodworking. Retired. Hobbyist. Forgotten more than I ever knew. Still trying to get the steppers to turn. I'll be lurking.