Parrallelism

[Ken379128]

I am writing a program and in the program I have the part dimensioned for Parrallelism the first part is coming out good but the second is always bad. I have watched it taking the hits on the part and the are making good contact. As well as changed partsand still the spec is .003 my first parts is coming out .0006 the second is between .003 and .0033

Thanks KC

Global Image
3.7 MR2

[bw_bob]

Could it be the 2nd part is actually bad. Can you check the parallelism with an indicator to verify its good or bad.

[cmmguy]

What's the question??

[John Kingston]

Could it be the 2nd part is actually bad. Can you check the parallelism with an indicator to verify its good or bad.

Good idea Bob. I can't reinforce how important it is to keep the surface plate inspection skills up to par. If you can't check it "old school", you can't do it on a CMM.

[Wes Cisco]

Or what happens if you reverse the order in which you run the two parts. Call them A & B, if you run A then B and A is good and B is out, what happens if you run B and then A? Is B good and then A out?

[Ken379128]

Yes part is good to plate inspection. Question is what Am I doing wrong. any suggetions. I lvl'd the planes I created for the parral but have not tried the program since. hope that does the trick but who know?

Global Image
3.7 MR2

[Paul Barriage]

My brain is steering me to ask,....

Is the alignment to a fixture? Or the part?

Is the final alignment done DCC? To each part?

[Ken379128]

Alignment is done to part and final alignment is DCC to one part I am however leveling the 2 planes for each part with an alignment.

[#2#]

Is this one program that will measure two parts with one execution? Or is it one program measuring one part, then you repeat with another part and get wonky results.

[Ken379128]

it is a program with an array of 3 rows of 10 the 1st and second piece of the 1st row I am measuring the parrall. after that I am not doing it because only 2 pcs are required for the final. Sorry for all the noob questioned and if I am not clear on everything guys.

[#2#]

I would double check to make absolutely sure you have dimensioned the parralleism of the correct planes. Make sure you aren't comparing a plane on the second part to a plane on the first part.

[John Kingston]

Alignment is done to part and final alignment is DCC to one part I am however leveling the 2 planes for each part with an alignment.

I think you need a DCC alignment to EACH part. Can you post part of the code? It'd help us to see it. Something might jump out at one of us. We've all had "annoyances" like this, another set of eyes usually sees it.

[#2#]

I think you need a DCC alignment to EACH part. Can you post part of the code? It'd help us to see it. Something might jump out at one of us. We've all had "annoyances" like this, another set of eyes usually sees it.

But does parrallelism depend on alignment? I don't think so and I don't think it is workplane dependent either as both features must be 3d features. Sure, the hit vectors for the planes would depend on alignment but I don't think that would make him .003 off. True, an alignment for each part would be the ideal situation but I don't think it is causing the problem.

[John Kingston]

But does parrallelism depend on alignment? I don't think so and I don't think it is workplane dependent either as both features must be 3d features. Sure, the hit vectors for the planes would depend on alignment but I don't think that would make him .003 off. True, an alignment for each part would be the ideal situation but I don't think it is causing the problem.

BUT, if the parallelism is to a datum & the datum is the initial alignment.......

[JoeRZ]

When parallellism is dimensioned won't you have to plug in the 2 planes, the "compare to" (1st) and the "datum" (second) regardless of alignments.

I'm wondering how much area are you looking at on both features?