Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: khalid on September 05, 2008, 02:47:04 PM

Title: Problems in Setting up 4th axis!!!
Post by: khalid on September 05, 2008, 02:47:04 PM
Hi Guys:).. Need ur help, recently I finished my 4th Axis and installed it on my DIY MDF Machine... Following are the settings:

1- My controller is set up in 1/2 step mode
2- Gear down ratio is 28: 108 (1 :3.857)
3- Stepper 1.8 deg. (200 steps)
4-My steps per degree will be 2 x 200 x 3.857 = 1542.8????/360?????
5-Pin Signal
   2 X axis Step
   3 X axis Direction
   4 Y axis Step
   5 Y axis Direction
   6 Z axis Step
   7 Z axis Direction
   8 A axis Step
   9 A axis Direction


Currently I am having following problems:

 ???- Currently getting weird problem in Mach3... Visual mill generated continuous rotary tool path and it looks good in simulation mode as shown in figure... But as soon i get the G code in the Mach3, I am finding the toolpath strange as shown in figure
Attached also my motor output, inputs and toolpath configuration setting,..

 ??? Please also check and confirm the A-axis motor tuning shown in my next post. Are the figures right.
Title: Re: Problems in Setting up 4th axis!!!
Post by: khalid on September 05, 2008, 02:48:59 PM
More pics:(
Please solve my problem:(
Title: Re: Problems in Setting up 4th axis!!!
Post by: Hood on September 05, 2008, 03:51:45 PM
Can you attach the code, I have never had an 4th axis but will have a look and see if I can figure anything out.
Hood
Title: Re: Problems in Setting up 4th axis!!!
Post by: khalid on September 05, 2008, 11:22:07 PM
Hood:) Thank you for reply. Here is the Gcode.. I downloaded the Mach3 Post processor from Mecsoft VisualMill website.
Title: Re: Problems in Setting up 4th axis!!!
Post by: Chip on September 07, 2008, 02:45:56 PM
Hi, Khalid

You need to set "A axis Dia". on Settings Page, 7 inches looks fairly close.

Chip
Title: Re: Problems in Setting up 4th axis!!!
Post by: khalid on September 08, 2008, 06:10:53 AM
Hi, Khalid

You need to set "A axis Dia". on Settings Page, 7 inches looks fairly close.

Chip

thank u Chip for ur reply:).. When i put all x,y, z to center of the part in Visuall Mill and send Gcode to Mach3 , it goes well (u can see the pictures). But in the Visual Mill tutorial they just keep Z-axis at the center and x,y at the top of the Stock...

Now when I follow visual mill tutorial i am getting weird results as posted above, wheras when i setting up all my axis at the center of the stock in visual mill, the part in Mach3 look nice..

I will commission my axis next week, just tweaking and adjusting my 4th axis now.

Now you have just adjust 7" dia in Mach3 and it also looks good..

Where I am Wrong??? i.e. follow the Visual mill tutorial and adjust the dia in Mach3 or just leave the VM tutorial take all my axis at center of stock and just cut the parts???

Can you please descibe what I should do???
Title: Re: Problems in Setting up 4th axis!!!
Post by: Chip on September 08, 2008, 06:11:39 PM
Hi, Khalid

The A axis Dia". on Settings Page is used to keep the cut speeds and display view proper for the part Dia.

Both methods should work fine, It just depends where you want to start your Z position from.

If I missed your point let me now, Chip
Title: Re: Problems in Setting up 4th axis!!!
Post by: khalid on September 09, 2008, 05:49:22 AM
Chip thank you for ur contineous support. I have few questions. Please answer.

1- If i take all the axis at centerpoint in Visual Mill. Then where i have to set 0 on actual workpiece on the machine? i.e. All the axis at the center of  the workpiece or the cutter tip at the top of workpiece ( cutter at top align to X-axis center).???

2). Now if i take the x and y at the workpiece top as shown in Visual Mill manual, then where i have to zero the Z or cutter tip???

3) In both cases above where the cutter will start cutting from? i.e if i set all axis to object center then whether the z (cutter) will itself goes to the object top and start cutting???

4) When simulating the 4th axis in Mach3 the A-axis DRO, the Gcode and all the things working fine. But as we seen in 3D milling the cutter toolpath in graphic windows for 4th axis not updated. Please tell me is it normal?

Title: Re: Problems in Setting up 4th axis!!!
Post by: Chip on September 09, 2008, 11:59:36 PM
Hi, Khalid

1., 2. Looks to me the Z0 should be set to top right of your work, X, Y right end above A axis CL (G Code you posted).

3. Most likely right end x,y,z center point Post the G Code for it.

4. In 4th axis there is no green last to current just the cross hairs.

Your 4th (A) axis Steps Per need to be 4.2855555 for 1 deg movement, 1548.2/360= 4.2855555.

Chip
Title: Re: Problems in Setting up 4th axis!!!
Post by: khalid on September 21, 2008, 05:09:26 AM
Thanks Chip for replying . In next 10 days I will able to machine a part. If I got any trouble , I hope you will solve. I will Keep seeking help from you.

Thanks and Best regards
Khalid