Y-axis travel not as coded in g-code - travels less

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pluto26

Y-axis travel not as coded in g-code - travels less

Post by pluto26 »

I am new to this CNC world so hopefully this is an user error.

When I generate g-code and Mach3 mills it there is one y cut that is off, it just does not go as far as it should.

this is what I did

table / system calibrated
created in AutoCad DXF
imported in Aspire created tabs and toolpath created g-code for g-code (inch)

it cuts the inner circle first
starts in lower left corner goes down, right and then up again this is where is does not travel as far as it should has

I have cut this piece a number or times and at diferrent start positions on the table the exact same result.
-calibration does not seems to be the issue


I included the DXF, g-code generated, pic from Aspire and a pic of the final cut.

any help wold be greatly appreciated.
Attachments
A_BM110F9.dxf
Created using AUtoCad
(22.29 KiB) Downloaded 212 times
Picture from Aspire
Picture from Aspire
Picture of finished cut piece, starts cutting outside from lower left going counter-clockwise
Picture of finished cut piece, starts cutting outside from lower left going counter-clockwise
A_BM110F9_Profile 2_after_update.txt
G-code generated by Aspire
(4.49 KiB) Downloaded 201 times

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zeeway
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Re: Y-axis travel not as coded in g-code - travels less

Post by zeeway »

Hmmmm...the left-right axis cuts seem to be the correct lengths, as far as I can tell. The north/south cuts, as oriented on your picture (is this your Y axis?), seem to be off.

I would check for a loose coupling screw/backlash on the axis that cuts north/south on your picture.

Does your cut end at the place where it started?

Can you cut a simple circle and a simple square okay?

Angie

davewierenga
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Joined: Mon Apr 25, 2011 1:28 am
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Re: Y-axis travel not as coded in g-code - travels less

Post by davewierenga »

If you don't find a loose coupling, try adjusting the acceleration and velocity in Mach.

Dave :D

pluto26

Re: Y-axis travel not as coded in g-code - travels less

Post by pluto26 »

It starts the cut in te lower left corner. the first move of the Y up (in the picture is short.

the cut ends in the correct stop also, the piece is fully cut.

I will look for backlash on the Y, but I would think I would see issues is erratic places on teh piece, not the exact same are and the exact same length off.


also adjecting velocity / accel, they are currently at 100 and 22 respectively, should I go higher or lower?

thanks for the suggestions.

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zeeway
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Re: Y-axis travel not as coded in g-code - travels less

Post by zeeway »

Feeds and speeds really depend on your machine, but I would try 50ipm, and 10 accel with the depth of cut no more than 1/2 the tool diameter.

Have you calibrated the x and y axis travel on your machine using the function on the Mach 3 Settings screen?

Angie

pluto26

Re: Y-axis travel not as coded in g-code - travels less

Post by pluto26 »

I will give it a try. right now everytime I try milling anything I get "limit switch" when the machine only moved 7" on the x-axis and 5" on the y-axis.

no where need the phyiscal limit switches. the logical limits are 42" for x and 24" for the Y.

the "abmornal condition" state axis are not refed to normal conditions"

should as I figure out how to clear this I will try your suggestions.

thanks for yor help.

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zeeway
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Re: Y-axis travel not as coded in g-code - travels less

Post by zeeway »

In Mach3 under Config/Homing Limits....make sure soft homing limits are set correctly there.

Angie

ger21
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Re: Y-axis travel not as coded in g-code - travels less

Post by ger21 »

Noise is triggering your limit switches. Either add capacitors to the inputs, or try increasing the debounce in General Config (upper right) to 3000-5000.

As for the Abnormal Condition, it's not really an error, and you can ignore it. It's just telling you you're homed in a different position than you did before. The best thing to do with that button/LED is remove it from the screen.
Gerry - http://www.thecncwoodworker.com

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