Calibration and setup of a star probe

[d.evans]

Can someone who has experience setting up and calibrating a star probe post some instructions on how to do it?

The only toolingball I have is the one with two .750" spheres mounted on a 45 degree angle. Also, I am trying to calibrate the 2 by 18 mm "fixed" star tip.

I tried to do it Friday and didn't get very far.

I also want to know how important it is to have the horizontal probes of the star aligned to the x and y axis of the table, and if they are not perfect, how much error can there be? The way this thing mounts appears to leave it completely up to the user to make sure it is square to the table.

I am using ver 3.7MR3, and a B&S Mistral 7.7.5. I also have a probe changer. But I plan on using one of the 4 TP20s I already am using with a single tip attached as the star. So, I'll have to recal to the single tip later, if needed.

I looked up info on this subj here and elsewhere, but what I found left LOTS of unanswered questions.

Your help is appreciated. TIA.

[bw_bob]

Which star do you want to qualify or do you want to do all and what angles. If your looking at the probe 1=straight down, 2 is to the right, 3 is to the back of the machine, 4 is to the left and 5 is straight ahead.

[d.evans]

angles

Which star do you want to qualify or do you wqnt to do all and what angles. If your looking at the probe 1=straight down, 2 is to the right, 3 is to the back of the machine, 4 is to the left and 5 is straight ahead.

I think that A0B0 and A0B45 ought to work for the part I'm going to have to measure. 2By18mm "fixed" tip.

[JamesMannes]

http://www.pcdmisforum.com/showthread.php?t=47

[John Kingston]

I use a star all the time. BUT, I don't rotate the head very often when using it. It is much easier to get a good calibration if the star is fairly square to the table. Here is how I do that.

1) Place 2 "1-2-3" blocks on the table. Get those square to the table. I use a Rayco fixture so this is pretty easy.

2) Move head so that one tip of the star is between the "1-2-3" blocks. Make the gap in the 123 blocks as small as possible.

3) Move head so that the 2tips perp to your first tip are parallel to the 123 block.

4) Tighten star in that position.

5) Calibrate the #1 tip. This is the tip pointing straight down.

6) Calibrate all tips. You may have some come up "out-of tolerance". Recalibrate only these. You may need to repeat that calibration a few times as the tips may be slightly out.

7) once all the tips are in I run all tips again. It usually works after 2 runs.

If you have any questions PM me.James pointed out a thread that has info in it. I still have the pics I sent to Wes. PM me your email address and I'll send it.