Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: cosmynnec on July 17, 2006, 12:30:15 PM

Title: Dwell question
Post by: cosmynnec on July 17, 2006, 12:30:15 PM
Hello, how can i trigger an output when the dwell command is active ? Thanks
Title: Re: Dwell question
Post by: fer_mayrl on July 17, 2006, 06:07:51 PM
I guess you could use a macro to do this. Set a macro to run on your gcode then on your macro, you could put something like this (im not too familiar with VB programing so I will put it just with normal words)

Activate output
DWELL
DeActivate output

Im sure Brian would actually know the syntax for it
Hope that would get you started though
Title: Re: Dwell question
Post by: Brian Barker on July 17, 2006, 07:16:48 PM
You will need to put it in a macropump...

It will look like this:

If GetLED(13) Then
ActivateSignal(OUTPUT1)
else
DeActivateSignal(OUTPUT1)
End if
Title: Re: Dwell question
Post by: fer_mayrl on July 17, 2006, 07:19:09 PM
You can easily tell who is the expert!
Title: Re: Dwell question
Post by: Brian Barker on July 17, 2006, 07:20:49 PM
 ;D
Title: Re: Dwell question
Post by: britishrich on July 18, 2009, 03:21:31 PM
Hey guys.

How can I change the dwell setting, mine is dwelling far too long and I am working with plastic so that is a big problem.
I found the G4 dwell setting in General Config but it is just a check box for ms...not a value?

It is currently unchecked...

Any help is appreciated, thanks.
Title: Re: Dwell question
Post by: Hood on July 18, 2009, 03:52:50 PM
Dwell time is instructed via code. If you have it set to milliseconds then G4P1 will be 1 millisecond, if set to seconds then it will be 1 second.
 Spindle Dwell can be set on General Config page.
Hood
Title: Re: Dwell question
Post by: britishrich on July 18, 2009, 05:08:22 PM
As I said above the general config page only shows a check box not a value (ms ON/OFF), what am I missing here?

If it is set in the code wouldn't that be in the CAM program then?

Thanks.
Title: Re: Dwell question
Post by: Hood on July 18, 2009, 05:11:57 PM
My apologies, spindle dwell is set from Config menu, Ports and Pins, Spindle Setup.
When are you getting the dwell?
Hood
Title: Re: Dwell question
Post by: britishrich on July 18, 2009, 05:34:57 PM
Forgive my novice ignorance but I am not sue what you mean by "where" ?

The dwell occurs anytime the spindle changes trajectory even on SINGLE lines, curves for example..
(only straight lines are ok)

Is that he info you were looking for?
Title: Re: Dwell question
Post by: Hood on July 18, 2009, 05:40:12 PM
Ok what you are seeing is the effects of exact stop (G61) What that means is the axis will come to a stop before the next executes, this should be instantaneous but if your acceleration is fairly low (as will be with steppers) then you will see it slowing and then speeding up at the next line.
 You can try with Constant Velocity (G64) what that does is it blends the present line of code with the next line and doesnt slow to a stop like with Exact Stop.
 To make sure you are running Constant Velocity look in your code and if you see a G61 remove it and place a G64 at the start of your code instead.
Hood
Title: Re: Dwell question
Post by: britishrich on July 18, 2009, 09:40:03 PM
So, I had no G61 or G64 in my code. It started with a G91.1 so I replaced that with a G64 an it's like my machine just doubled in value LOL Beautiful smooth movements :)
Thank you so much.

Now, is it possible to make it put the G64 in the code without havin to do it manually??

Thanks Hood!

PS - G91.1 being removed didn't seem to make any difference (several runs without it now) but for peace of mind does anyone know what 91.1 is?
Title: Re: Dwell question
Post by: Hood on July 19, 2009, 04:11:14 AM
Your post processor for your CAM should be able to be altered to add the G64, you can also change things on the General Config page so that the default for Mach is Constant Velocity. The problem with relying solely on that however is it can be changed by the code so best to get your CAM to do it if possible.
 G91.1 is Incremental  for IJK mode, you want to keep that in your code as well, no need to remove it, just have the G64 on the line after it.

Hood
Title: Re: Dwell question
Post by: britishrich on July 19, 2009, 11:46:10 AM
Sweet thanks. I'll go tinker with Lcam....and  put the G91.1 back in...

Who says the Scots and the English don't get along??? hahaha

cheers mate.
Title: Re: Dwell question
Post by: Hood on July 19, 2009, 05:21:21 PM
Now if only I had known you were English ;D
Hood
Title: Re: Dwell question
Post by: britishrich on July 19, 2009, 05:45:46 PM
LOL Good thing being in FL got me used to saying "British" (the yanks don't know the difference LOL)
Title: Re: Dwell question
Post by: britishrich on July 19, 2009, 05:46:32 PM
PS - IF I put the G64 in the code after the G91.1 what "N" should I give it??
Title: Re: Dwell question
Post by: Hood on July 19, 2009, 05:58:30 PM
Presume you are meaning the line number when you say N? If so put it on the same line as the G91.1 or if you want it on the next line for any reason dont bother with a line number. Mach doesnt care about line numbers they are just there for your convienience, personally I dont like or use them.
Hood
Title: Re: Dwell question
Post by: britishrich on July 24, 2009, 08:15:52 PM
Cool thanks - being a total newb I have no clue what is ESSENTIAL or MEANINGLESS yet LOL
Title: Re: Dwell question
Post by: simpson36 on July 30, 2009, 10:53:29 AM
Next to the big red reset button on the Mach screen is a smaller button that says G-code. Try that one out.
Title: Re: Dwell question
Post by: britishrich on July 30, 2009, 12:18:18 PM
Cool, that reference does look helpful :)

I don't suppose there is one that makes it ignore rapid heights for lines that SHOULD be connected?
I couldn't see one but of coure I don't know what all the terms mean just yet.

(my LCAM won't join chains as well as it could...tried many different tolerance levels and manually joining primitives etc to no avail)