Messages

411

General Mach Discussion / Re: Losing Steps on x

« on: November 19, 2012, 12:37:54 PM »

Tweakie, I too have experienced this or a similar issue in 1 of my set ups. This is the only variable I didnt accept. I figured if it would run mach, good enough. But there is something subtly different. In my case reducing speeds did help but I dont find it an acceptable solution. I think I still have an extra card around here somewhere.

412

General Mach Discussion / What would cause my limit switches to trip?

« on: November 19, 2012, 08:48:12 AM »

Without the V- tied in the potentials will be different still allowing the problem to exist in my understanding. The caps didn't help mine but they were a cheap solution or preventative. You could also use a ferrite on the PP cable.

413

General Mach Discussion / How to set table size and limit home switches

« on: November 17, 2012, 11:28:30 PM »

IIRC on the "offsets" page but you would have to go back to that page each time a touch off was required. You could just do a touch off and enter the thickness of your touch plate in the dro, press enter.

414

General Mach Discussion / What would cause my limit switches to trip?

« on: November 17, 2012, 11:24:57 PM »

The fear of that V- being tied into that same bolt is what caused my delay of the repair too. Finally after being frustrated and not completely understanding the advice given me, I blindly jumpered it thinking maybe I would pull the jumper off real fast if the magic smoke started coming out. Right, fortunately that didn't happen and it has worked great ever since.

415

General Mach Discussion / Re: What would cause my limit switches to trip?

« on: November 17, 2012, 07:01:29 PM »

Ok so a little clarification. A star ground is a central point to where all the ground wires (chassis ground), limit switch shields and the V- of your power supply tie into. This is usually a screw or bolt on the chassis of the controller. This is to minimize ground loops. The debounce setting in Mach 3 (there are 2, one is for the spindle the other for the limit switches). This setting is a time that a signal has to be present before Mach 3 sees it. In this case we are talking about the debounce interval. It is in microseconds (40us per unit). A small number of anything less than 500 is usually acceptable. The machine will continue to travel in the same direction for (500 x 40 x .0000001seconds or .002 of a second) til Mach recognizes the signal. How far will your machine travel in that time? This is a software work around for noise. If your V- is only powering your controller or drives and is not tied into the chassis ground, I would lay odds that is the issue. I would tie it into the same place as the chassis ground anyway. It is an accepted practice. try the debounce at 500, if it works, try again at 250. Keep cutting it in half til it reappears. When it does reappear, double the debounce. Personally I fought this issue for years and tried caps, resistors, shields separating stepper and limit switch wires. Nothing helped until I connected that V- to the chassis ground. Now I can remove all the other fixes at the same time and still not get a false trip. Are you a member on CncZone? Check out their electronics section. this question comes up all of the time.

416

General Mach Discussion / Re: How to set table size and limit home switches

« on: November 17, 2012, 04:38:27 PM »

Install tool of your choice in spindle, record diameter first.
Touch the tool to the side of your work in X, hit "zero" X.
"                                                        " Y hit "zero" Y
"                                                        " Z hit'zero" Z
Lift the Z clear of the work. Hit go to zero.
In MDI type X (1/2 diameter of tool), Y (1/2 diameter of tool) "enter"
Machine will now move tool to the new 0,0,0,
"Zero the X and Y. (Z is already correct) The theoretical tool center is now over the corner of your work.

417

General Mach Discussion / Re: What would cause my limit switches to trip?

« on: November 17, 2012, 04:29:08 PM »

Yep. What kind of grounding technique are you using? Do you use a star ground? If not the problem could be there. Does the V- of your power supply tie down to the chassis ground too? Also do run any debounce on the general config page of Mach3?

418

General Mach Discussion / Questions 1st Aluminum Cut Sample

« on: November 17, 2012, 09:50:58 AM »

Both ways are very good at improving cut quality. Definitely try both ways. It is surprising the difference in results, especially small mills not Bridgeports and the like.

419

General Mach Discussion / Questions 1st Aluminum Cut Sample

« on: November 16, 2012, 08:04:34 PM »

There are many ways to skin a cat. You are performing a separate drilling op? Though that is a very acceptable method. I can't figure out why you don't ramp into the part. It would minimize the tool change. Sorry I spoke before looking at the attachment. It looks like the tool is going to depth and then a circular lead in, and a circular lead out is being used. That is what I was referring to a while back. It is starting the cut in the scrap side.

420

General Mach Discussion / Questions 1st Aluminum Cut Sample

« on: November 14, 2012, 08:55:20 AM »

I am so glad you found those parameters. They will make your results so much better. I didn't and don't expect you to understand MC fully as very few probably do. I have looked at a version or 2 of MC but it was alien to me, I started with BobCad and am now using CamBam too. They each have their little differences in use but likely can accomplish the same or similar results. Progress is being made on your part and soon your results, enjoyment and tool life will all improve. Keep posting as we will all learn.