Messages

91

General Mach Discussion / Re: Spindle speed fedback?

« on: June 19, 2011, 08:19:01 PM »

This looks like the beginnings of turning the spindle into effectively a big servo. Doing this with my mill spindle would enable rigid tapping ... I like that idea. Distant dream, or not?

92

General Mach Discussion / Re: Z plunges too far and ruins jobs; Mach misses lines; wailing/gnashing of teeth

« on: June 19, 2011, 02:09:03 PM »

Could be that, I detuned the motors a little and made a point of pumping the oiler and exercising the slides first thing and it hasn't happened recently. The toolpath showed the correct position along with the DROs. The other embuggerance is an occasional runaway of the X and Y axes - the DROs update slowly, about once every two seconds, and simply show rapidly rising (or falling) values carrying the tool along an uncommanded 45 degree path as fast as it will go. The toolpath shows it going, but makes no effort to stop it. Nedless to say, not good. I solved this once by leaving G41 on between subroutine executions instead of cancelling and reapplying it each time, but it's come back in a different program. Do I need to cancel G41 before using G0 or is this something else? It's a horrendous error and not one I want to repeat.

I don't think it's a HDD failure as the computer is nearly new and fairly decent in other respects. There have been no bothers such as slow booting or hanging.

93

General Mach Discussion / Z plunges too far and ruins jobs; Mach misses lines; wailing/gnashing of teeth

« on: June 18, 2011, 12:11:47 PM »

I've had a persistent, if intermittent problem with Mach3: My Z axis tends to get carried away and plunge too far (or not retract fully). The results are as dire as you'd expect - Ruined work, lost time and broken tools. I've got a hole in the top of my vice with an expensive 8mm cutter snapped of in it from the last episode. This isn't something I can reproduce as it only happens infrequently. Any clues on this? I'm getting a bit paranoid about it since I've got some big milling jobs to get through shortly and I don't want them going wrong.

The other point that may be related is that Mach occasionally seems to skip instructions or stop short of a finishing point. This is usually when approaching the end o a cut with a G41 offset on - instead of continuing to the end of a a cut it stops significantly short before lifting the spindle. The only way i can correct this is by programming the same line twice.

Again, any clues on this? This BS is giving me ulcers just thinking about it 

94

General Mach Discussion / Re: Is there a thread dedicated to n00bs here?

« on: June 18, 2011, 12:00:36 PM »

Sounds like an ideal application for Mach3. I'd vote for little stubby bits as well, they are ideal for sheel metal.

If you need very precise holes drilling then you can use an endmill and a G13 command to make a pocket - This give you a lovely "adjustable drillbit" efect that lets you specify the hole size exactly.

95

Show"N"Tell ( Your Machines) / Re: RICH'S ATLAS CNC CONVERSION

« on: June 03, 2011, 01:08:11 PM »

Very useful and very flexible, and saves writing programs for odd jobs if you can still use the old handles. Well done

96

General Mach Discussion / Re: Problem with computer running mach3

« on: June 03, 2011, 11:24:03 AM »

I replaced my computer with a new Dell unit a while back and it sounds odd when the steppers run. It has the original Dell OEM install of XP Pro and two Moschip parallell cards. The steppers have a sort of whingey note to them which speaks of ill things, and it doesn't run as fast as it should without losing steps (or halting). I'm considering the option of a fresh install of bog-standard basic-as-hell XP, rather than the funny Dell setup, as there are probably a lot of Dell-specific background processes that I really don't need for making chips. I'll see how I get on with it and report back.

97

General Mach Discussion / Re: Mach skips lines: what's going on?

« on: May 24, 2011, 09:17:18 AM »

ok, cheers - Will reinstall wiith the driver in place and report back.

98

General Mach Discussion / Mach skips lines: what's going on?

« on: May 24, 2011, 09:10:35 AM »

I've written a very simple program for Mach3, and running it in simulation on my laptop, it skips the first few moves and goes straight into the g03 from where it is. Needless to say this is a right old nonsense.

My laptop is a 64 bit Winows 7 Professional machine, and the error occurs in regualar W7 and XP mode.

G64 G21 G15 G40 G49
G0 Z20
G0 X0 Y150 {STARTING POSITION}
G41 P6.00
G0 X3.75 Y0
G03 X 3.75 Y0 I32 J0
M30
%

I've tried littering it with dwell commands to try to prompt it to find the first few lines but to no avail. I've also tried replacing the initial rapids with fast g01 commands, and repeating the first move to the starting position several times. It just starts from where it is and gets into the G03 move. I'm stumped.

Any ideas?

99

Show"N"Tell ( What you have made with your CNC machine.) / Re: MODEL 629 S&W MAGNUM

« on: May 02, 2011, 05:19:34 PM »

Perhaps you'd be better off using the Classic Hunter barrel with the full lug underneath, you'd have something to grip onto at least. I had a (blued) 29 classic hunter, it was an awesome old hogleg and great fun to shoot with full power train-stopper loads. Details aside, awesome project ... tiny stuff like this is very demanding work.

100

Share Your GCode / Re: Suppressor Designs?

« on: May 02, 2011, 03:34:55 PM »

You could make a small spinning tool out of steel and spin odd shaped bits on a small, fast lathe: use annealed 1000 series aluminium. This gets you moving easily and quicky and at very low cost if you wanted recurved or nautilus baffles.