can mach3 control rotation head for vertical saw blade

[mwgranit]

Hi, I have built a bridge CNC 4axis saw to cut kitchen worksurfaces. The blade motor is attached to the Zaxis with a rotary table. I have all the axis working with mach3, but would like to know if Mach3 can control the rotational saw head to cut in any direction according to the DXF drawing. If it can, how do I set it up to travel in the direction the blade is aming?
Thanks
Curt Kilian
Granite Objects
South Africa

[Hood]

Have a look at the tangential knife control. I have never used it but seem to recall that it will not work with arcs but rather needs the arcs to be lots of short segments, but that is just from memory so may not be the case   I think the manual may have some info but if not do a search here for tangential knife and hopefully you will get some info.
Hood

[mwgranit]

thank you, i have checked it out. I am convinced it will work!

[fer_mayrl]

just be aware that when using tangential knife, the cutter follows a curve while rotating the blade,
this is mainly used for vinyl cutting where the blade just barely pierces the material.

I assume that you are just cutting straight lines and most corners will be 90 degrees, make sure that the blade moves up on all direction changes, I'm not sure if that is possible, i've never worked with tangential knife control.
I believe there is a lift angle dro and a lift z dro, im guessing just put the angle to 1, and the lift just so your blade moves out of the material.

Regards
Fernando

[ostie01]

I think this could be easy to do if you program it manually with Z axis and A axis as rotation.

Program would be simple as it is only X Y code.

Lift the saw, rotational move, move down the saw and G1 X?, lift the saw.

Need to know the exact center of the A axis and the offset between center and saw.

Jeff

[fer_mayrl]

I agree with ostie,
Comming up with a CAM program that can output the toolpath for a setup like this will be difficult, specially with the difference of width of cut and diameter of the blade.
I might be wrong and some CAM packages might have a module for that or something

[mwgranit]

Thanks All.

The problem I has was that if I wanted to do a straight cut at for eg. 33deg - there is no JOG or MOVE button to tell the machine to now move into the direction which the blade is facing.

I have solved the problem by adding a new Manual input screen for the saw blade use with one MOVE button extra. I have entered VB code to make the machine move into the direction which the blade is pointing at for a set distance at g01 feed by just clicking the button. Now, I just aim the laser to the required cut direction, enter the required cut distance in a DRO and click the MOVE button. It works great - I can now cut into any 0-360deg direction. Works great for templates which are marked on the stone.

[poppabear]

you could also use G68 coordinate plane rotations, that you would just need to enter the angle that the saw blade is, in relation to true 0 degrees, once you rotate your coordinate system, and say for instance move X4", it would move in the new X0 to X4 along that angle since the X plane for instance would be "along" the new rotated angle.....

scott