trouble with y movement

[aokweld101]

So, if I'm doing my math right normal settings for a litho are .180 depth and 450 height leaving .07 material left so should I try to make sure that leave .07 thickness left?

[bergerud]

If the normal depth is 0.180 then you should change it to 0.180 - 0.032 = 0.148 since the machine will carve it 0.032 deeper and you will actually get 0.180.

(This is assuming that the centering slot on your machine is the same as the one on mine.)

[aokweld101]

I had my settings today mostly by trial and error. mostly error.. I started out with my pipe at 3.51 O.D. the thickness of the pipe was .233... I ended up making the depth at .109 and the region at .100 which leaves .071 on the thickness left and .08 on the region. I might add that I did it at .120 depth and went through the wall of the pipe.

[bergerud]

I might add that I did it at .120 depth and went through the wall of the pipe.

I guess there is something else also going on as well. How true does the pipe spin on the jig? How did you make the pipe holders? Did you use a lathe? Like, Michael, I would like to see some pictures of the setup.

You know, you could use the z encoder data to actually measure the depths. Put the bit at the touch position on the jig and turn on the machine. Choose 0 - 7 down arrow to y and z data. The data will read 0.000. Now move the truck over and touch on the pipe. The center of the jig is 1.75 below the touch. If the pipe in 3.5 in diameter, the z should also read 0.000 on the pipe. (Also, spin the pipe around taking readings to see how true it is.) Maybe you can figure out what is not measuring up.

[aokweld101]

I should know that being around machinist for 34 yrs. but I did'nt think of it at the time... I'm a welder what could a couple of thousand mean any way...lol..

[aokweld101]

Dan, I checked the z height and touched it to the jig plate and zero'ed it out moved it over to the pipe and read .041 moved it back to the the jig fixture and thouched it and read .011 and is staying constistant at .011-jig...pipe at .041 I 'm useing the drain plug that Mike suggested in his post for centering. so how do I set the depth?

[bergerud]

How is the pipe for being out of round? Maybe you could put the jig up on blocks (so it will rotate) and use the z data to check the out of round. If it is out of round by too much, you will not be able to make a decent litho.

[aokweld101]

Dan, the majic number was .112 for the region and .112 for the pattern it if I went any deeper it would go throught the pipe..next one I'm doing is .109 for the region and .113 for the pattern try to get the picture just a little bit lighter.

[bergerud]

If the pipe does not spin true, it will be a crap shoot. Someday I want to try these things.