How to Lock Dimension Nominal and Limit Values for a Family Table

[zrehlander]

Hey everyone,

I am working on a family table for some gears at work. I went through and made my model and when I go to dimension it we type in the nominal value (for this example 3.752).  After I have everything revolved and want to change the dimensions from nominal to limits I go into the dimensions tab set my upper limit at 0.004 and my lower at 0.000. This way when I type other members into the family I should be able to just type in the lower limit and when I get my drawing the upper should be automatically 0.004 larger (3.756).

So to recap my

nominal is 3.752  (that I type into my family table)

lower should be 3.752

upper should be 3.756

But, When I am doing this Pro E Wildfire 4.0 is changing my nominal dimension for 3.752 to 3.754 and changes the limits to upper 0.002 and lower 0.002, so for the first drawing it works out but now whenever I put a new member into my family they not the limits that I want. I tried using the toggle lock command but it did not change anything and my dimensions were still changing.

Any ideas?

Thanks,

Zach

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[zrehlander]

but some how when I enter the upper value in for my nominal and set the upper tol to 0.000 and the lower to 0.004 it does not change my nominal and it works fine.

[rcook · Accepted solution]

The nominal value will be halfway between your lower and upper values when using a limit tolerance. It sounds like you want to enter the lower limit in your family table, not the nominal? I don't think that you can get directly at the lower limit value to put in the FT. You could create a parameter for the lower limit and then a relation to calculate the nominal and then put the parameter in the FT.

E.g.

Create a Real Number parameter called LOWER.

Add relation dXX = LOWER + 0.002

Add LOWER to the FT

Now you can enter the lower limit into the family table, nominal value will be 0.002 more than the lower limit, upper limit will be 0.004 higher that the lower limit.

Alternatively, you could just display the dimension with a Plus-Minus tolerance (nominal +0.004/-0) and then add the nominal to the FT (same as lower in this case).