Messages

831

General Mach Discussion / Re: upgrade problems

« on: March 10, 2008, 08:54:48 AM »

You should have a look at the video tutorials.  There is one on scripting, which covers the writing of simple Vis Basic programs, and the one covered is specifically for tool changing.

Basically - depending if you have your tool table up to date, you can for an M6 call, move the axis to a suitable place to change the tool, change the tool, and then have it automatically return to the job and carry on. All offsets are taken up automatically.

I have only come to Mach3 recently, but I think in this latest lockdown, quite a few on the configurations have changed, to make them more flexible, but probably the are also more complicated to get running.

832

General Mach Discussion / Re: Backlash compensation for a rotary axis ?

« on: March 10, 2008, 08:24:54 AM »

Greg - I'm sorry about the diatribe for backlash - and I am quite sure you understand it. I just get carried away sometimes.

Do I understand that this circular table, using the angular axis, will move to a new position, and then stand still whilst the other axis go to work on it.

If so - I know this sounds crude - but I would put a parking brake on it.

There are several options - a belt round the table that can wind on like a garrot, an electric disc brake that might be better because you could control it through software, or my son ( who weighs 22 stone and loves going down mountains on his bike) puts his faith in bicycle brakes - the latest disc brakes are awsome in their power - I now use them on miniature railway engines. They are compact and easy to fit and have hydraulic or cable operation. Or, in the picture you have posted, a drilled and taped hole for a screw onto the main shaft of the gearbox.

833

General Mach Discussion / Re: Steppers DEAD!

« on: March 10, 2008, 08:07:08 AM »

Having studied the pictures - this is a standard system of output from LPT1. At first I did not see it, but I just have (having written all the rest of the reply).
There is an enable jumper - labelled JP2 - the legend reads, I think -
Top - External - 4 - Enables Drives - Normal
Bottom  - Drivers always enabled

Check if you have any of these jumpers connected. I personally would connect the bottom one - and have the drivers enabled all the time otherwise, I assume, your will need some sort of enable/disable switch for it.

If this was the problem - ignore the rest of the diatribe.

 Assuming this unit is working correctly, I can see no reason why your system should not work.

Try this and see what happens.

Get one motor - preferably away from the lathe/mill on a workbench or somewhere. Connect your unit to it on the X motor set of contacts. Connect the power supply to the unit. Turn on the unit. You should hear a clunk from the motor and if you try and turn the motor manually it should put a a good resistance to being moved. If this is the case, we must assume that the unit is working correctly.

Turn to your computer - with Mach3. I assume you want the miller with three axis (although to set up does not make that much difference).
Before connecting your computer to the lathe -
Try jogging the axis - do the DRO's jog up and down. If they do not check on Config/System Hotkeys and set the jogg keys to what you like - generally X and Y go on the up and down, left and right arrows, I have my Z on page up, page down. Click the jog you want to set, and press the keyboard key to set it.
If the axis will now jog turn to Config/Ports and Pins. Ensure the top left PORT1 is enabled.
Same page, select Motor Outputs - you will have to set up these as the instructions on the top of your driver unit. As well as step and direction don't forget the step port, direction port which should be 1.

Switch off the driver unit, plug in your printer cable and turn back on. You should get the same clunk. Your motor should now respond to jog controls for the X drive motor.

If this is working so far, you are home and dry.

You can test all the outputs from the computer by merely setting the same output pins for the Y and Z axis and seeing if they work.
You can test your driver by connecting the motor to the other two outputs and repeating the same tests - altering the pin numbers to suit.

If it hasn't worked this far there are some other tests you can try on the LPT1 port (principally to check the voltage your computer is putting out - which should be 5volts - some computers only put out 3.5volts which is not enough for reliable operation).
As far as tesing the driver card, that is a bit beyond me, but if you can borrow another computer and test Mach3 on that, that is the way to go.

834

General Mach Discussion / Re: Steppers DEAD!

« on: March 09, 2008, 04:40:33 AM »

No - a much better idea would be ( seeing it is winter over here in the UK) - for a small consideration, I will fly out and spend some time with you diagnosing the problem over a few beers.

If we can't manage that, I suppose the video will have to do.

835

General Mach Discussion / Re: Turning a Morse taper

« on: March 09, 2008, 04:12:50 AM »

Please don't misunderstand this post - I am a great believer in working things out for myself, and seeing what I think is the nub of the problem. The wizards are very good, and I use them myself, but - when things go wrong it leaves you high and dry trying to guess the problem.


Why are you bothering with the handy dandy trig table and the Wizard - you have the figures in front of you.

For every foot the taper is 0.59941 so the GCode is  (from 0,0) G1 Z12 X-0.59941.

You cannot do a straight cut - you will have to do some roughing cuts - but it is as simple as that.

If you are doing anything short of 1 foot - say 3,4 or 6 inches, divide the amount of taper by 4,3 or 2.

I haven't checked whether the taper applies to diameter or radius, as Bill said - but you can just alter the lathe from radius mode to diameter mode - wthout altering the maths.

Now if you did that and it didn't fit we can find out why, but unless I take the wizard apart line by line, I don't know.

I'm sure Bill has the answer, and I am sure your second go will work, but try writing simple GCode, it is quite rewarding.

836

General Mach Discussion / Re: Backlash compensation for a rotary axis ?

« on: March 09, 2008, 03:53:55 AM »

I cannot understand your problem with backlash. Mach3 deals with backlash perfectly. I have a cheap lathe which has quite a lot of backlash. This summer I will deal with it, and probably put in ball screws - but until then Mach 3 deals with it and it is accurate to the thousanth of an inch.

You would be able to, I am sure, deal with backlash on a manual machine, I think we have all done that at one time or another - on Mach3 it is just the same, but the computer does it for you.

All backlash is is the non-movement of the "table" whilst the gears, belts etc etc settle down to pulling the other way.

On any system, to check it - use typed gCode commands, switch off backlash compensation -  move one way - stop, set measure to 0 - move same way for some distance ( the distance does not matter,because backlash has nothing to do with distance, but you can say move one inch and check the table is moving accurately) - stop - reverse back to start.

Your measure should now read 0 - but it will not - this is backlash. Enter it in the table and switch on backlash compensation.

It is simple and accurate and all mechanical systems must have it, otherwise they would seize up - it is only when it gets big enough to notice it becomes a problem.

The only problem I can see with a rotary table is measuring the backlash - I have things to measure to a thou, but nothing that will measure to a degreee (accurately). I suppose you could convert to thous and then convert back - it depends on how you set up the axis.

837

General Mach Discussion / Re: Steppers DEAD!

« on: March 08, 2008, 07:50:54 AM »

If you are saying there is no torque on the steppers when the system is on, that means there is no power to them so check out the power supply and make sure a fuse hasn't blown or whatever. 

Another feature on some boards is a "disable all axis" pin that has to be grounded before the axis work - check if you have one, and make sure it is permanently grounded, or if it is grounded. make sure it is a good firm connection.

Pardon me asking - has this system ever worked - if it has, what has changed (if anything) to make it not work. This will give us a clue as to what might be wrong.

838

General Mach Discussion / Re: mach3 problem with operator interface

« on: March 08, 2008, 04:42:10 AM »

Sorry- I missed the operator interface the first time I looked at the site. This is certainly an interesting board.

Right - where to start. If you have used the OEM's and got them working via the standard key board, I would, I think wire up a couple of push buttons to your interface and try and "convert" them first.

Does the operators interface have preselected codes for each of the 32 inputs
I would, I think use Mach 3 against itself - Try going into Config/Hot Keys and selecting one of the jogging inputs - use A B or C, I don't think it will matter - and instead of pressing a key on the key board, toggle your rotary switch or press a switch on your interface and see what scan code it is putting out - and more important - is Mach3 picking it up.  I don't know if you have written any code for the OEM's but it may be that the scan codes need sorting out.

At least, if you can see that Mach3 is picking up the scan codes from your interface, we should be able to work out how to get it to do what you want.

839

General Mach Discussion / Re: mach3 problem with operator interface

« on: March 08, 2008, 03:57:29 AM »

I have just read your post again -

If you have connected these rotary switches into your BOB - what signal do they give to the computer.
A rotary switch, by design, gives different values as it changes, whereas push buttons give a pulse.
How have you wired the rotary switch to differentiate between counting up and counting down???

840

General Mach Discussion / Re: mach3 problem with operator interface

« on: March 08, 2008, 03:53:40 AM »

I take it the spindle speed has nothing to do with Mach3 - but is controlled by some other electronics.

Does the rotary switch put out a pulse, or is it continuously connected to the position it is at. Does it make before break, or break before make when changing. The only rotaries I am familiar with are electronics wafer types.

As you can see, Mach is designed to run through a keyboard, which has all the necessary debounce circuits etc already in. Keyboards are designed to put out pulses.

I can see the advantage of rotaries - because you can label and look to see where they are set - but a simple way would be to replace the feedrate rotaries with two external push buttons, feeding into the input side of the computer - and your present logic will require only a minor change.

Other than that I feel that you will have to analyse the signals coming out of your rotaries, and write macros to include signal debounce etc, the fact that they are on all the time (or whatever). (A simple problem could be - if the swtiches are "on" all the time in one position - that mechanical bounce is causing intermittent signals to your computer)

There are, on the market several hand held, plug in,  control panels that already do what you are trying - or are at least programmable to do it. They, I am sure will have got round all the "electronic" problems and might be the answer ( I have no idea of cost, however)