Messages

3821

VB and the development of wizards / Re: Any new WIZARD ideas to work on ???

« on: October 19, 2012, 04:44:27 PM »

Dan a thought about multipass is to make the Root radius a variable starting with it being the same as the MAJOR diameter then do each complete pass based on that depth then lower the Radius value  a step and repeat. That is basically how I had planned to do it. It ADDS a lot more LOOPS BUT it should not cut air either.

CAM lobe as in engine camshafts are a beast math wise. You have a nonconcentric lobe and a ROUND gringing wheel that wears as it goes.  The point of contact to calculate depth of cut is a huge variable based on lobe rotation vs wheel diam. Basically is is a forever changing variable that you have to account for.

The big boys do it differently as they do it as a Live axis that Follows the contour mathematicaly like a C axis on the lathe as a live axis GEARED to the rotation of the spindle. EMC2 can do this but not mach3 as of yet.

I have the math here BUT not the brains to make it work ON THE FLY in mach3,  YET.

Another tuffy is a crank grinder easier than a LOBEas the shape is consistant but the variable is that the cut axis dips below the Zero point of the axis and the mat has has to invert.  

I cheat and use a special POST in sheetcam to do the path then use the Scale trick to cut the lobes also each lobe path loop  alternates with another to help keep heat out of the lobe. AND it generates a HUGE Gcode file. AN eight cylinder cam will generate well over a MILLION lines of code in mach3.

Been there done that one already(;-)  , (;-) TP

3822

General Mach Discussion / Re: BT30 spindle from scratch - with power drawbar and ATC of course

« on: October 19, 2012, 04:00:22 PM »

Getting close to miller time(;-)

(;-) TP

3823

VB and the development of wizards / Re: Any new WIZARD ideas to work on ???

« on: October 19, 2012, 03:43:35 PM »

Practical Application ??  Probably not as you see the rake angles are extreme and the Power needed to  rotate the shaft slowly and cut is HIGH  and not readily available on a DIY type lathe. ALSO most lathes do NOT have an encoder to run it as a 4th or follow mode.

IT is just NEAT to think about.

(;-) TP

3824

General Mach Discussion / Re: Run From Here hangs on M03

« on: October 19, 2012, 02:32:42 PM »

AH I see you found the catch 22 with plasma and many of the sub fucntions such as Rehome and G31. (;-)

You cannot run the RFH IF you use the G28.1 or the G31 routines to find the top of material (TOM).  The G28.1 will actually try to run BUT your Z will end up in outerspace NOT at the top of material.

You just use the Set Next Line and then have at it. IF needed you prerun the TOM routine next to your restart point prior to restarting your cut code.
NOTE that using the SNL you must NOT try to start on a line that contains ARC data as it cannot restart in an arc.  Mach will erro out because it does not have all the arc data to run the arc.

Just a thought, (;-) TP

3825

VB and the development of wizards / Re: Any new WIZARD ideas to work on ???

« on: October 19, 2012, 02:01:41 PM »

OK Makes sense. What you are describing would be the Root Radius of the flats?  Hard to measure diam across a 3 sided object (;-)

One easy way at this point to make it multpass would be to scale the routine oversize on the first pass then reduce the scale for each pass down to the root diam of the flat.

We do this with cam grinding to make it simple as the math there is horribly complicated.

(;-) TP

3826

VB and the development of wizards / Re: Any new WIZARD ideas to work on ???

« on: October 19, 2012, 12:33:21 PM »

Dan I redid the front end of YOUR code to solve for the Flat lengths based on Diameter of shaft and #of flats.

D  =  Diameter of shaft
C = angle of flats (360/#flats)
R= (D/2)  Convert to Radius

Chord length = ((2*R) * Sin(C/2))

NOW you can input the major functions via front end macro to program the Polygon function.

Shaft Diameter
#flats
Flat length

It does the same thing as you did only makes it a touch easier for the OP to program on the fly.

Just a thought, (;-) TP

3827

VB and the development of wizards / Re: Any new WIZARD ideas to work on ???

« on: October 19, 2012, 11:25:58 AM »

You did good DAN, What I am working on has a couple of good points. You do not have to know what the flats distance is Just what the shaft diam is and the # of flats.

A simple set of  Question boxes for the inputs will work fine.

THE ugly part of it is the MATH to swing an arc into and out of a cirlce (;-) Still working on that part.

GUYS G91 can be your friend OR your enemy.

I have an old hit and miss engine here that sounds a LOT like that.


(;-) TP

3828

VB and the development of wizards / Re: Any new WIZARD ideas to work on ???

« on: October 19, 2012, 12:10:45 AM »

Dan here is what I meant for cutting the flats like a thread.  The Program is just a demo I cooked up to test the idea. THe math is NOT DONE for cutting the flats as an arc(working on that part). THere is just a simple cut where the flats arc CODE will be.

It creates the proper number of flats as requested.  AND yes SOME of the math is fixed for now more Variables to be added later.

It runs like a thread cutting the flats along the way AND then come back and cuts the flat deeper and so on until you get to the end value of the flat.

Just a thought, (;-) TP

3829

Mach SDK plugin questions and answers. / Re: Input Multiplexing

« on: October 18, 2012, 11:04:39 PM »

I think you missed the point. To do MUXing in mach3 you need a plugin to control the Mach3 side AND you need a BOB that has the MUX controls code built into the board to control the flip flopping of the signals.

A standard BOB cannot do MUXing in mach3.

I do not see where you board can do MACH3 MUXing.

Just  a thought, (;-) TP

3830

G-Code, CAD, and CAM discussions / Re: Symmetry problem... Is the problem in mach 3 set up?

« on: October 18, 2012, 10:56:05 PM »

I checked teh DXF file it is fine , I checked the Gcode file it iooks ok, I converted the Gcode file back to a dxf and verified it is fine as well.

That eliminates the drawing and the Gcode.

That leaves the machine and mach3. Mach3 is NOT known to be wrong in its geometry. Are you running any FORMULAS in MACH3??

That leaves out of square machine, lost steps, Cutting deflection, Slow ACCELL for feedrate causing CV to compensate.

BUT you say you have veried the square and deflection and exact stop cuts the same.

NOW they ALL can't be right and it still cut wrong (;-). I would go back and check everything machine related step by step until you find the problem.

(;-) TP