Messages

1

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 23, 2008, 07:30:58 PM »

Well I suppose you could always roll up your sleeves and get programming to fix it. Since there is no Windows based competitior for Mach3, having comp pretty close to fully functional is a better option than we've had to date.

Well that's exactly what I'm doing. Not programming, but extensive testing of the new code which Brian was kind enough to give me and advance copy of. I've in return been giving him all the feedback I can, both offline and on. Its best to get these things sorted while they are being worked on rather than revisiting them later. The comp crowd has waited a long time for some attention and now that we getting it, I'm making the most of it. Brian has invited the comments and feedback and I've been giving them. Mach has become the top class product it is through user involvement and feedback. It sounds like you have a problem with this process....

Graham

2

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 23, 2008, 11:18:38 AM »

Seems to me that specifying a cutter diameter .0001" undersize (even if the cutter is onsize) will result in 50 millionths error in the part whilst allowing the comp path to run. My mill can't split .00005", can yours?
Joe

Hi Joe

I think you missing the point. Its fine to do that, if you know about it and know what to do as a fudge to make it work. The fact is that it remains a fudge and does not work as someone would reasonably expect it to. Do you enter all your cutters in the tool table .0001 undersized? Its not about the error in the part but the fact you had to follow special procedures to use comp.

Graham

3

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 23, 2008, 01:06:44 AM »

Okay it will now run the part.. I have tested it on as many files as I can find and they all work without killing the part.
I have changed the price of mach3 to reflect this enhancement LOL (there will be a 10% increase the first of the year and that is not a joke... )

Sounds good Brian, I knew the bitching would pay off.    Let me know when I can give it a run...

Graham

4

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 23, 2008, 01:02:20 AM »

Hello Graham H. ,
Just a note if you are going to use the P for setting the offset amount. the P is the offset ammount not the DIA of the tool that you would like to run..

So G41 P.25 would be what you would put in for a .5 tool

Yes that is correct. in my example above you will see I was using .5 radius arcs with a 1 inch diameter cutter (.5 radius hence P.5000). I could have used .25 arcs with a P word of .2500 or .125 arcs with a P word of .1250, its all the same thing. None of those will work.

I agree that any cutter less than .5 will work with .5 arcs....  What we discussing is if the arc is the same as the cutter radius.

Graham

5

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 22, 2008, 10:28:32 PM »

If you round your numbers in the cad system to the safe side (Make the arc bigger by where you place the arc center) I can be sure that I cut all the parts right..  I can not change Mach3 to round because the guys running micro machines will have trouble. You need to fix it on your side and I need to run many types of machines.

The following comp code is a simple square with 1 inch sides and .5 arc corners. If you look at the I and J words of the four corner arcs you will see they are all exactly .5000 or .0000 so there has been no rounding on the CAM side. These are the exact coordinates in the precise location and yet the new comp code will not work with it. If I change the G42 P.5000 line to G42 P.499999999999 it works fine. That would indicate the error is on the Mach side and not with the CAM as there would be no rounding I could do on the CAM side to fix this.

Using the R-word in place of an I and J is not really an option as it has its own problems with ambiguity of arcs greater than 180 degrees. 

G00 Z.3
G00 X0 Y0
G00 X1.5000 Y-.2500
G42 P.5000
G00 Z.1000
G01 Z-.1000 F10
G01 X.7500 Y-.2500 F20
G02 X.0000 Y.5000 I.0000 J.7500
G01 X.0000 Y1.0000
G02 X.5000 Y1.5000 I.5000 J.0000
G01 X1.5000 Y1.5000
G02 X2.0000 Y1.0000 I.0000 J-.5000
G01 X2.0000 Y.0000
G02 X1.5000 Y-.5000 I-.5000 J.0000
G01 X.5000 Y-.5000
G02 X.0000 Y.0000 I.0000 J.5000
G01 X.0000 Y.5000
G02 X.7500 Y1.2500 I.7500 J.0000
G40  (cancel cutter radius comp)
G01 X1.5000 Y1.2500
G00 Z.3

Graham

6

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 22, 2008, 07:32:06 PM »

Yes the tool must be less.. You could se the same size tool if you use R style progamming   The problem that I have is the rounding from the cam programs... I can't make a .5 tool fit in a .499999 space.. The math blows up..

But right now a .5 tool wont fit a .5 space. The problem as I see it is, if the gcode is only to 4 decimal places, so the space you trying to fit the tool into should also only be calculated to 4 places. By using double float math, an arc calculated as .5000000001 should be rounded to .5000 as the original I or J word was .5000. The resolution of the error should not exceed the resolution of the gcode.

Graham  

7

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 22, 2008, 07:21:20 PM »

so what is wrong with using a 6mm (.236") cutter

Nothing wrong with that unless you live in USA, Liberia or Myanmar (the last three countries in the world using imperial measurement) or unless you have 3mm inside arcs.   

I guess you've never tried to buy a 6mm cutter in the USA, they hard to find and cost twice that of an imperial cutter. But really where does this reduction end? A .5 cutter should fit a .25 arc.

Graham

8

General Mach Discussion / Re: New Cutter Comp code and Examples

« on: December 22, 2008, 12:03:07 PM »

Rule 3.

You can not use a cutter larger than the smallest internal diameter, if your smallest rad is .25" then the largest cutter you can use is .5" diameter.

Rule 3 is the only one I think is a problem with the new comp. Firstly the rule says the inside arcs must be greater than the comp, and I found this to be the case in my testing of the new comp code.

So if the smallest rad is .25 then the largest cutter must be .4999 or smaller. A .5 cuter with a comp of .25 wont work as its equal to the smallest arc. Very limiting as code with .125 inside arcs almost cant be cut now.

Graham Hollis

9

Competitions / Re: ******Guess and win a G100 Grex******

« on: May 16, 2007, 12:21:23 AM »

Considering feed, spindle speed and size of part remaining.... 2305100

10

Third party software and hardware support forums. / D2nc release V1.2

« on: November 21, 2006, 09:05:57 PM »

Version 1.2 of D2nc is online at www.d2nc.com

There have been several major changes since the last release. The display routines has been completely rewritten using OpenGL graphics which improves the look and feel of the program. There is enhanced functionally in the shape description language with the introduction of a tangent line function. Examples of its use is in the tutorial. The installer has been improved to allow a standalone install of D2nc so you can run it from the desktop or launch it from with in Mach3. A modified Mach3 screen set for Mach3 V2.x which adds D2nc integration is included.

The website has seen some changes. There are now screenshots along with a brief video demo of D2nc in use, as well as some sample shape definitions showing the power of the shape description language. I hope to add more videos in the near future.

To celebrate this new release I have a promotional price through the end of the year. I welcome any and all feedback or suggestions.

Many thanks,
Graham
www.d2nc.com