Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: mikecahill on April 04, 2011, 08:52:16 AM

Title: copycat, cutting an arc in the xz plane
Post by: mikecahill on April 04, 2011, 08:52:16 AM
Sorry it's probably just me, but I can't find a manual for copycat, I want to be able to cut an arc in the xz plane, using copycat, it just doesn't  want to do it, I am picking a start, middle and end point, but instead of describing a concave arc on the xz plane,it starts at the start point, and then the z axis rises, until by the time x reaches it's end point it is about an inch above where it should be, it works as a "v" if tell it to go in straight line moves, why not an arc?
Cheers
Mike
Title: Re: copycat, cutting an arc in the xz plane
Post by: RICH on April 04, 2011, 12:05:57 PM
Mike,
There is a manual for Copycat in MEMBERS DOC's.
No other information exists other than what is in the manual.
If it's not in there, well, i guess......your on your own.

BTW, You need a NFS license to post code from it if I remember correctly.
RICH
Title: Re: copycat, cutting an arc in the xz plane
Post by: mikecahill on April 04, 2011, 02:10:56 PM
Had what I thought was a brainwave, and lowered z axis 0.0 point to below the lowest point in the arc, so that it stayed in positive numbers because the error message said it couldn't divide by zero, but it hasn't made any difference, anyone else had this problem, and worked out a workaround?
cheers
mike
Title: Re: copycat, cutting an arc in the xz plane
Post by: BR549 on April 04, 2011, 03:48:24 PM
It appears the Copy Cat does not allow arcs ouside of the G17 plane(XY) even thought it will produce a spiral (;-)

(;-) TP

Title: Re: copycat, cutting an arc in the xz plane
Post by: mikecahill on April 04, 2011, 04:14:34 PM
It appears the Copy Cat does not allow arcs ouside of the G17 plane(XY) even thought it will produce a spiral (;-)

(;-) TP


I don't understand that, I can't be the only person who wants to cut a dish shaped profile, what is the difference between xy and xz movements? is this a bug in the software?
cheers
mike
Title: Re: copycat, cutting an arc in the xz plane
Post by: Overloaded on April 04, 2011, 04:53:25 PM
Hi Mike,
  I'd say that it's not the software (Mach) or a bug, but rather a limitation of the Wizard.
When you hit the "New Teach File" button you can see G17 planted in the preamble.
Ron Ginger might share some insight on the subject as he is the Wizard Master.
Russ
Title: Re: copycat, cutting an arc in the xz plane
Post by: RICH on April 04, 2011, 05:17:28 PM
Mike,
There are some basic differences. The ZX ( G18 ) defines a different plane of reference for the arc motion as to what is cw or ccw ( GO2 / G033 ) and uses IK instead of IJ. So to get the arc motion correct the G18 plane is called out in the code, and if not,  ie; I& J are used in G17 you will get an error. Now something you may want to try is just use the Y axis instead of the Z axis ( swap cables ) or for that matter manipulate the produced Gcode.

BTW, Your the first person to post something on CopyCat in a long time. If you have a camera and an XBox  you can do some neat stuff for tracing out patterns and generating gcode for them. Now I know there is more than one user........ ;)

Have fun,
RICH



Title: Re: copycat, cutting an arc in the xz plane
Post by: mikecahill on April 04, 2011, 05:56:33 PM
got a camera, but no xbox, I was thinking of rigging up a couple of laser pointers to locate the place where the beams coincide "a la dam busters" what is the story with the xbox? won't a computer do?
Title: Re: copycat, cutting an arc in the xz plane
Post by: BR549 on April 04, 2011, 05:56:41 PM
You will also find that mach cannot do an arc in the G19/19 planes IF it is offset from the parent plane in a radial fashion. Such as cutting a bowl using only G17 arcs and rotating around the centerpoint with the arcs to form the bowl.  It would require a 3rd operator to define the arc through the 3 planes at the same time.

But that is just the way it has always been, so nothing new. You just have to learn to work around it.

(;-) TP
Title: Re: copycat, cutting an arc in the xz plane
Post by: mikecahill on April 04, 2011, 06:09:58 PM
I'll try the trick with swopping the leads, let you know how it works out
Title: Re: copycat, cutting an arc in the xz plane
Post by: RICH on April 04, 2011, 08:35:57 PM
Lee wrote a plug in for using Microsofts X360 controller. You can use computer keys to move around but it is so much easier to follow a profile with the
handheld controller. It can be set up a number of different ways, thus you can go fast or just creap along sort of like an MPG to or from a viewed point.
I only use it for copying things, which is not to often, but works just great for the intended purpose. Have a look in the manual and you will find how i increased the magnification when using a $19 webcam from Radio Shack. I wanted a fairly good manification of the part along with a reasonable working distance from the piece.
BTW, you want a webcam which has a manual  adjustable focus.

RICH
Title: Re: copycat, cutting an arc in the xz plane
Post by: mikecahill on April 06, 2011, 03:53:41 PM
well, as suggested, I swopped the Y and Z leads over, and went through the plotting process, and it worked!! I rigged a retractable ball point pen as a probe which when it pressed a contact made from a little strip of brass, it lit a bulb, it worked fine, the only problem was when I told the machine to "goto zero"