Machsupport Forum

G-Code, CAD, and CAM => G-Code, CAD, and CAM discussions => Topic started by: dave_c24 on May 05, 2013, 01:07:28 PM

Title: Unwanted datum shift in x axis
Post by: dave_c24 on May 05, 2013, 01:07:28 PM
Hi.

I'm hoping someone here can help. I'm new to Mach 3 but recently bought a hobby mill (3040 router) off eBay brand new that came with a version of Mach 3. It seems whenever I run a program over around 400-500 lines I get a datum shift in the x axis and the part is ruined

I have tested the machine in MDI and checked to see if its a motor error by checking repeated movements over 150mm in the x and it is within 0.02mm

When running a small component say 75mm x25mm with 3 small pockets and a profile it comes out fine. A larger component with say 3mm pockets and a profile say 230mm x150mm comes out wrong all pockets are perfect in size and position then the machine loses position by the cutter size in the x while contouring. I've tried for 2weeks to solve it on my own

I've updated from mach3 version 1.9 (came with mill) to the latest version from the site but still getting the problem.

I've tried different cam program's different components but always I get this error through any program on larger items.

Please help

Many thanks

Dave
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 05:42:26 AM
Hi Dave,

From the problem you describe it sounds as though you may need to check that your Mach3 licence is valid.

Contact Mach Support license@machsupport.com. and they will verify its authenticity.

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 05:48:34 AM
Hi

Thanks for the reply I will check ASAP. What information do I need to provide them. It says its licences to papa fabio?? I've uninstalled it all and re installed it and it still uses that licence ?

 I have been experimenting and found the problem is occurring during x/y angle profile moves. The x motor is producing a clunk when moving in the positive direction. I keep trying all motor tuning settings but no cure. Tried low and high speen and it actual seems better at high speed??

Cheers

Dave
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 06:00:33 AM
Hi Dave,

The 'Papa Fabio' is a pirate license. You need to purchase a genuine license from Artsoft for your machine to work correctly.  ;)

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 06:04:38 AM
im tempted to buy it im on the screen to but if it doesnt fix it i cannot get a refund :-(

you obviously have experience of this  ;)
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 06:23:17 AM
Quote
you obviously have experience of this 

Indeed I do sir.

Perhaps your best option is to go into your Mach3 folder and delete the file 'Mach1Lic.dat' then stick to running GCode programs that do not exceed the 500 line limit.
Then if you are satisfied that Mach3 is the machine control software for you - purchase a genuine licence and have many years of happy machining like the rest of us.
The choice is all yours and after all it is excellent value for money.

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: RICH on May 06, 2013, 06:31:32 AM
Dave,
Can you post a link to the EBAY listing where you bought it.

RICH
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 07:03:40 AM
Dave,
Can you post a link to the EBAY listing where you bought it.

RICH

hi its this one

http://www.ebay.co.uk/itm/181091373085
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 07:04:54 AM
Quote
you obviously have experience of this 

Indeed I do sir.

Perhaps your best option is to go into your Mach3 folder and delete the file 'Mach1Lic.dat' then stick to running GCode programs that do not exceed the 500 line limit.
Then if you are satisfied that Mach3 is the machine control software for you - purchase a genuine licence and have many years of happy machining like the rest of us.
The choice is all yours and after all it is excellent value for money.

Tweakie.

hi

i will try that after dinner and see how i get on and let you know. i have emailed the seller and they say they will send me new software and correct setting but have not recived it :-(
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 07:21:53 AM
hi, just tried it in demo mode and still getting the same fault its out by around 1mm in x-
the motor is still clunking on x/y moves

ive attached g code

cheers

Dave
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 07:41:43 AM
Hi Dave,

Your GCode appears OK with all 4 passes exactly the same.

As you are getting errors then I think the problem lies with your machine. You could be loosing steps, perhaps as a result of electrical noise or possibly tightness or binding of your axis linear bearings or lead-screws ?

Are your stepper motors running hot ?

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 07:45:30 AM
Hi

Yes all motors are getting pretty warm and after alot of runs nearly too hot to touch. When the machine is off the hand wheels on the motors allow you to move the axis with ease. Is there any other checks I can do?
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 08:18:55 AM
Dave,

With hobby machines the steppers should run warm to the touch but not too hot that you cannot keep your hand on them comfortably after a few hours of running. Perhaps reducing the drive current would help.

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 08:22:03 AM
Excuse me being a newbie but how do I reduce the drive current lol. I tuned the motors down to 1500 max velocity test n got the accuracy better but frustrating to have to slow the mill
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 11:01:16 AM
Quote
Excuse me being a newbie but how do I reduce the drive current lol.

That is a function of your driver board - you would need to check your manufacturers instruction manual for how to set motor current.

What driver do you have ?

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 11:06:18 AM
hi, thanks for another reply. i havent got a clue sorry. its the one that came with the machine in the control box?

http://www.ebay.co.uk/itm/181091373085

is the ebay listing any use?
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 11:56:15 AM
That’s not any help so looks like you will have to leave the motors running hot until you can get some further information.

Something else you may wish to check…

In the Mach3 folder is ‘DriverTest.exe’ – run it and see if the result is a nice straight line.

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 12:02:37 PM
hi,

i ran that test today also and it said that it was excellent in the green bar, only a very very tiny spikes
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 06, 2013, 12:15:18 PM
Tiny spikes are OK so it is unlikely to be a PC related issue.

Looks like I have just about exhausted my ideas on this one for the moment, sorry.  :'(

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 12:19:19 PM
Thank you for your repeated help. I have also just run shearline mode as suggested by Scott at Mach support at a low feed (200) it's ok but anything higher and problem returns. I am now running in demo mode a licence was a pirate copy

Many thanks

Dave
Title: Re: Unwanted datum shift in x axis
Post by: Graham Waterworth on May 06, 2013, 12:22:44 PM
I want to know what the noise is.

If its a loose ball nut or bearing/housing or motor mount then that can cause problems with position.  I would check all the clamps, nuts and bolts first and make sure every thing is solid.  It has been known for ball nuts to be loose in the housing and sliding about.

Graham
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 12:28:35 PM
I will have a check over all tonight, I checked the guide rails they were tight but I need to disassemble the gantry to get to rest.

Whatever causes this is definitely on the x axis and only on positive moves especially wen moving in y as well . As said before swapping motors doesn't cure it. I know all motor mounts are tight

Cheers
Dave
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 06, 2013, 03:23:34 PM
Hi all

Problem is now solved thanks to Scott at Mach support. It has turned out to be a fault with the x drive in the control box, we have swapped it with the z and it is now running perfectly. Now I need to get a replacement from the eBay seller but I doubt that will happen :-/

Thanks for everyone's input

Cheers

Dave
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 07, 2013, 02:06:27 AM
Hi Dave,

I am pleased that you have found the problem.  :)

Perhaps if you post a couple of pictures of the inside of your control box someone may know of a suitable replacement for the defective drive (assuming that the seller does not come up with the goods).

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 07, 2013, 02:26:37 AM
I have a pic on my phone but at the moment can't post it as it keeps saying there is already one of the same name. Im Wondering about replacing the whole box with one of the boxes you can buy from ebay such as this one
190827938360

Cheers

Dave
Title: Re: Unwanted datum shift in x axis
Post by: Tweakie.CNC on May 07, 2013, 03:12:43 AM
Couldn't say one way or the other if that box is OK - certainly the bay description sounds good and the price is good as well but the overall quality will be an unknown.

If you want a quality product with excellent documentation and backup then the Gecko drives take a lot of beating http://www.geckodrive.com/geckodrive-step-motor-drives.html but there will be UK import duties / vat on top of the price.

Does you existing controller look like this one ?

(http://www.machsupport.com/forum/index.php?action=dlattach;topic=24409.0;attach=34632;image)

Tweakie.
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 07, 2013, 03:17:30 AM
Ah ok. I see your point. I'll look at the gecko drives.

No my box has one card that does all 3 axis that's around 120mm x 90mm at a guess with toshiba chips on it

I've been messages this morning by the seller, stating they will replace the card but first I need to video the error occurring, how can I do this when it takes 20min to shift 2mm.

Ran the machine last night with cards swapped cut profiles lovely but now I have no control over depth . It slowly gets lower and lower lol

Cheers

Dave
Title: Re: Unwanted datum shift in x axis
Post by: dave_c24 on May 07, 2013, 01:24:48 PM
hi

heres a pic of my driver board from inside my control box. the seller from ebay has now said they will send a replacement board but when asked when it will arrive has not responded >:(

Title: Re: Unwanted datum shift in x axis
Post by: PeterMcK on June 04, 2013, 10:37:48 PM
 >:(I am using Powermill and Mach 3 on a Novakon Torus mill.  I am making a simple 2 1/2 D part with a profile and some holes drilled in it.  When it comes to a tool change, it seems to lose its coordinates and wander of in to space.  Has anyone had this problem?