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View Full Version : Standard cuts for testing a new machine.

Saracen
21-01-2013, 04:14 PM
Are there standard cuts people use to test the operation and straightness of a newly constructed machine ?

I'm thinking along the lines of:

1) Checking bed is flat and moves to limits correctly - for fixed gantry machines.
2) Checking the X/Y are set up to move equally. eg: cuts a circle not an ellipse.
3) Checking the spindle is vertical in X and Y axes and moves vertically in the Z axis.

Web Goblin
21-01-2013, 07:12 PM
Cut a square and measure the diagonals. Should be equal length. If not then the machines not square.

Shinobiwan
21-01-2013, 10:42 PM
For best accuracy you should ideally cut a square that's around you travel limits. If you don't have a long digital rule to do that then this method works well:

MechMate CNC Router Forum : <font color="ff0000">&#42;</font> Setting the Y-axis square to the X-axis (http://www.mechmate.com/Forum/messages/9/3316.html)

GEOFFREY
21-01-2013, 11:30 PM
Hi, a very simple check that I use is to cut two circles of the same diameter, one offset inside the line, the other outside the line. the larger circle should be a perfect fit in the smaller hole, and should fit in any position, but friction will mean it will not rotate too freely. G.

Lee Roberts
22-01-2013, 07:09 PM
Cut a circle, measure it across 5 points :onthego:

Jonathan
22-01-2013, 08:18 PM
An easier way to check how close your X and Y axes are to square is just to drill 3 holes, the same diameter, to make a (should be) right angled triangle. i.e. Holes at (0,0) , (X,0) , (0,Y). You can then measure the 3 lengths and use that to either calculate the angle, or draw a diagram in a cad program and measure it. There are less errors in this method then cutting a shape, in addition to it requiring less material - could even just use the bed if it's MDF.