Thread: Alpha Zoot ... new aussie machine on the way!

Great work Alan.

Looks great. Can't wait to see the chips. I also really like the idea of your side control station with the estop. Keep up the great work.

Daniel

Alan

Your machine is looking great and you have every right to be proud of it.

It might be an idea to just rearrange some of the wiring in your box.

In the area marked red. Maybe strive for just a small amount of physical separation between the power (to drives and from drives to steppers) and the low voltage signal wires from BoB to drives.

Don't get too carried away, but some separation would be good.

Greg

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Thanks for the comments Greg. What you don't pick up in the photo of my 'rats nest' wiring is that the wires from the drives to the steppers are a couple of inches in front of the drives and they go up to an area where I make the actual connections to the stepper wiring. I will look at the wiring to the drives as I have power and signal wires 'neatly' bundled together!

I am up and running today ... have zero'd the table and cut a few test squares to fine tune the steps. I have set out below what my current settings are, because something is still not quite right and I get a message from Mach4 when I open it saying ... "Warning, one or more axis are tuned too fast for the current kernal speed of 25,000".

X (&A) 4:1 reduction with R&P ... 106.5 steps / 4500 velocity / 300 acceleration
Y no reduction & 1605 ballscrews ... 400.4 steps / 3600 velocity / 766 acceleration
Z no reduction & 1605 ballscrews ... 400.4 steps / 3600 velocity / 570 acceleration

Any suggestions?

The only other problem I see with this initial setup is that when I cut a square, 2 of the corners are rounded. I had a similar problem when I originally set up my Widgitmaster and changed the IJ Mode to 'Inc' which solved the issue then, but does not seem to make any difference when I make that change on this machine.

Cheers,

Alan

PS ... I cut a circle and it seemed round and was giving me a feed rate of 3,470.

Hi Alan,

Go to config page and set your parallel port kernal speed to the next highest starting at 35000hz until the message disappears. Don't overcook this as it takes up CPU time.
What is happening is the computer cannot send enough pulses at the speed setting you have to keep up with the step and speed requirements of you machine.
Save and shut down Mach3 then retune your motors.
This should get rid of the error message.

Yes as Rod suggested, a modern computer should have no dificulty at 35khz.

Set step and direction pulse time to 3. Step and direction pins to active low ( I THINK, I should check on this for the G251s)

I would expect that you will do better in acceleration than you have at present, particularly on X.

This will make a difference on the corner rounding which will be due to the Constant Velocity.

Incremental arcs should be normal default setting.

Greg

Thanks Rod & Greg for your super prompt help.

I changed the kernal speed to 35,000Hz and restarted and yes, got rid of my warning message.

I set the step and direction pulse times to 3 and made the step and direction pins to active low ... Peter Homann had mentioned this in his schematic as well.

The other thing that I did after examining every setting on my Widgitmaster was to change the "Stop CV for angles > " to 30° and square corners now come out square!

I have done a few test runs and everything seems to be working OK. I have tested out a few of my 1/4" router bits ... 90° and found that most don't give me as tidy a cut for bevelled lettering as my original 1/8" bits, but I will go on experimenting. Certainly with bigger letters I probably don't need the corners as sharp as the small letters anyway.

Cutting scrap MDF the machine seems to be accurate on all axis, but will try out some alum to finally fine tune the steps. I have been running the spindle at 12,000rpm and am amazed how quiet it is and air cooled, does not get hot at all. I will try out some faster speeds tomorrow.

Thanks again for all your help.

Alan

Hi Alan,
Great to hear it is settling down.

The likely cause of your lack of fine detail is that you are running the spindle at 12,000 RPM. The fine detail is done with the tip of the cutter therefore you need the spindle at max RPM for it to cut verses tear the material away.

You should get exactly the same finish as the Widgit so don't be concerned about what you are getting at the moment.

Greg,
I am having an issue with my Z Zero. I had copied the profile across from the Widgitmaster before I modified it for the 4 steppers and slaving etc and I had Rod's Z Zero on it so that it talked to me when things were happening ... it was a favourite show off when anyone was looking at the machine, however on the new machine the Z axis did not move down at all, just moved up the 20mm and told me that everything was zeroed.

So I copied your latest code into the zero button and the same thing happens! No movement down and then just the final move up 20mm.

Can you suggest what I am doing wrong? I initially tried to type the code in and try as I may, it kept telling me I had a syntax error, so that is why I did a copy and paste of your code so that I did not have any errors. The touch plate shows up as touching and I don't need an earth (no ceramic bearings!).

Cheers,

Alan

Alan

Open the macro up in the VB editor. Then step through one line at a time. This often helps to see exactly where things are happening.

Most likely you are getting false triggers due to noise. So the probe input gets a signal even though it has not touched.

In the old days you could enter a high debounce value to see if that made a difference, but debounce now has no effect on probe input.

You can disconnect the long wire to the touch plate and try with a very short connection of probe input to ground. Just a temp test connection that you can short to ground pin by hand. This is unlikely to pick up noise unless it is really bad.

Greg

Hi Alan,
Is the machine bedded down now and do we get to see a video of it working?

Rod,
I am still having problems with the Z Zero ... as Greg has said, probably noise and I have tried a few things, but not resolved it yet. I have got very used to the Z Zero on the Widgitmaster and am missing it on the main machine.

I have cut a few small things and it all works well, but need to get the Limit Switches working, the E Stop and the Z Zero going before I really feel that I have finished.

I have connected up the Shuttle Pro and that works well and am just trying different combos of switches etc.

Does anyone know what sort of oil goes into the vacuum pump? Am running low and have lost my vacuum, which is a pain!!

Cheers,

Alan

Hi Alan,
I use microphone shielded wire for my Z zero plate. It is two wire rubber coated and copper shielded here . I ground the shield at the bob end only. Haven't had a problem with any of my machines but that mumbo jumbo electronics is tricky.
One of the versions of mach3 gave me trouble with the zero plate - it was something to do with the wait state I think but it was longer than ten minutes ago so I have forgotten the real reason.

In any case if you are using smoothstepper you should download the latest plugin from their site (Warp9) and at the same time get the latest lock down version of Mach3. Smothstepper have fixed a few problems but more importantly have allowed feed rate override to go above 100%. The latest Mach3 lockdown is needed for this upgrade and it might make your zero plate problem magically disappear as well.

At a guess I would say a light non foaming oil such as normal air compressor pump oil would do the trick on your vacuum pump.

Today, I was cutting a sign and unfortunately I had set the tool to cut 5mm depth into hardwood ... far too agressive! It worked fine on my MDF sample, but when it started to cut it stalled after about 10mm.

I hit 'stop' immediately and as I have my spindle operating independently of the steppers, it kept going, so I thought I could just rejig and change the cutting depth to say 3mm and start again, HOWEVER neither my Y or Z axis will move at all ... when I turn the drivers on I get no detent from either of these axis, but the X is working fine.

The drivers still have their little red lights and there is no visible signs of fire and there was no magic smoke.

What could have come unstuck? What is the best way to test? Could something have become unhinged in Mach3 or have I stuffed the steppers?

Suggestions willingly accepted!

Cheers,

Alan

Hi Alan,
It sounds like a driver problem to me.
Quick check is to swap the wires at the driver from your Y axis motor over to one of your X axis drives. Fire up the system and see if the Y axis motor locks up but most important do not jog as you only have one true X axis drive connected and it will skew your gantry. This will tell you if it is the driver or the motor.
As a note this will only work if you wired up all your motors and drives the same.
If the Y axis motor locks up on the X axis driver then looks like it is the driver but could also be the bob or computer problem. You can eliminate the bob and computer by swapping wires over there.
Oh yeah before you start swapping over other wiring replace the X axis wiring while you remember.
I hope I have suitably confused you as much as I have confused myself typing this but I am sure you will work through the logic of it.
Good luck.