iterative help needed

[d.evans]

I have a cylinder shaped part and every time I try to do an iterative alignment, I get the dreaded "Iterative Alignment Error".

I picked up 3 points on one of the flat surfaces near one end of the part, two points spaced pretty close together(on the OD) relatively close to 0,0,1 vector for rotate, and a final point (on the OD) of the cylinder at 0,1,0. I can get it to go measure the features in dcc, but after it measures the last one, I get "Iterative Alignment Error".

Any ideas? There are no circles I can use that follow the iterative rules, that I know of. All the circular features are the same vector, and same center.

3.7MR3

[Perry Fisher]

I'm not as good with iterative alignments as other on this board but have you tried a Best Fit alignment?

What is that part? It looks like a necking die for can manufacturing.

[d.evans]

It is a vacuum sensor body for spaceflight hardware. Stainless steel. 1.000" OD, .620" length. I haven't tried a BF.

[Matthew D. Hoedeman]

If it is a round object with NOTHING to keep it from 'spinning', then you will not be able to do an iterative alignment. In fact, best bet, measure a plane that it is going to sit on, measure the bore, do a 'regular' alignment. With no 'clocking' feature, the rotation is not a problem. Level to the plane, set XY origin to the bore, set Z origin to the plane, ignore the rotation, set the offset, CAD=PART, you are ready to check and report.

[cmmguy]

Perry, you know he has to kill you now, right?

[d.evans]

thanks, Matthew. I'll give it a whirl.

[craiger_ny]

What are the tolerances, who is the customer and how much are you selling it for?

[d.evans]

I have the part set up "sideways" so I can reach both ends of the cylinder. THere are features that must be reached that way. Anyway, I picked up three hits on a flat at one end, made a plane from them, Then I measured a circle in the center of the part (the 'thru' hole). Executed them one at a time. Then I did insert/alignment/leveled Xplus to pln1, chose nothing for rotate, origined y and z to the measured circle, origined x to the pln1. Then hit CAD=PART. and I'll be a monkey's uncle, but it worked.
Thanks MATT!!!!!!!!

[d.evans]

What are the tolerances, who is the customer and how much are you selling it for?

Why do you ask?
The tolerances are tight. OD at one end is +/- .001". ID at the other end is +.000/-.002". O-ring groove ID is +/- .003".

[Perry Fisher]

Perry, you know he has to kill you now, right?

I didn't ask who his customer is.

I worked in the can tooling industry for 15 years. I've seen way more dies shaped like that than I care to remember. If his part has diametric tolerances like can tooling, ±.00015", a CMM is not the way to go.

Besides, He's in Alabama so I can only guess he's a good ole Southerner like me.

[craiger_ny]

Why do you ask?
The tolerances are tight. OD at one end is +/- .001". ID at the other end is +.000/-.002". O-ring groove ID is +/- .003".

I was kidding. I was picking up on J's joke about you having to kill Perry after divulging in information about the part that's all. I have nothing to offer.

[JamesMannes]

Not true, oh Craiger of the New York land!!! You have victuals and beer to offer!!!

[cmmguy]

Not true, oh Craiger of the New York land!!! You have victuals and beer to offer!!!

Stop using those big words.... I had to go and look up victuals

[djayne]

Pronunciation: 'vi-t&l
Function: noun
Etymology: Middle English vitaille, victuayle, from Anglo-French, from Late Latin victualia, plural, provisions, victuals, from neuter plural of victualis of nourishment, from Latin victus nourishment, way of living, from vivere to live -- more at QUICK
1 : food usable by people
2 plural : supplies of food : PROVISIONS

[d.evans]

sorry

I was kidding. I was picking up on J's joke about you having to kill Perry after divulging in information about the part that's all. I have nothing to offer.

that one went right over my bald head. I'm often (and rightly so) accused of being too 'literal'.