[zevenwolf]

4th Axis Changing zero from center of piece to outside

I am trying out my 4th axis for the first time.

My piece is milling "correctly" when I zero to the center of my stock.

Right now I am running my machine in the air because it would just ram into my material.

When I run it off to the side of the piece it seems to be milling correctly.

I would like to setup it up where the zero is the outside of my stock.

I included my model

thanks

[Gregore]

Can you reframe the question as it does not make much sense with the forth axis . It does with 2.5 and 3D . Why do you want the outside surface of the model to be zero?

Also is your 4th axis in the y ?

[zevenwolf]

I am new to using a 4th axis or rotary axis.

I want the outside to be zero on the outside because if it is based on the center of the stock then the machine rams into the stock.

[Gregore]

It sounds like you are doing a finish path before the roughing path? Is this the case? Or is it the case of you are using the roughing path but you are having the cut start too deep into the material on the first pass. if this is the case then you have 2 options

1 lie to the madcam about your stock size by saying it is bigger than it really is then you will be doing a little air cutting before the real cutting starts

2 or if you 5 axis version you can tell it to cut a little above the drive surface in the drive surface options box , this will achieve the same outcome.

When I cut metal I usually have to lie to the cam in one way or the other as my cutters are so small ( less than 1 mm with a .1 mm step down that even .2 mm off on surface location will cause me to have broken cutters)

What I would suggest to start with is buy some machinable wax and learn on that as it is way cheaper than end mills.

MachinableWax.com

[BurrMan]

I am new to using a 4th axis or rotary axis.

I want the outside to be zero on the outside because if it is based on the center of the stock then the machine rams into the stock.

You'll want to leave the zero at the rotation axis. There are a few answers depending on what you are doing. (I dont know MadCam so cant really direct you in there)

"The machine RAMS into the stock....."

What code is doing this? Start and stop? You can setup "machine AND work coords" so starting and ending is done at different areas.

Usually though, the CAM software has a "top" setting, so your "STOCK" is set to be the rad/diameter of the material.

If you dont have these options, then you can set your post to "stop" at ends or toolchange positions and manually jog the z out of the way.