# Design Tables, Configurations, and the Hole Wizard

Question asked by Jason McCrory on Sep 8, 2009
Latest reply on Sep 9, 2009 by Tony Hayes

I am modeling up a line of heat exchangers for use in our assembly parts library. I'm using a design table to drive configurations of the heat exchanger, since the same general shape covers 4 diameters and 6 or so lengths of them.

I'm using a design table to drive the 40 or so combinations we need, and I'm running into a problem with the pipe tap sizing using the hole wizard...

First - a caveat: We use specific depths for our NPT threading as a thread engagement. So even though the default thread depth for a (example)1"NPT hole 0.66" in the hole wizard, we set the tap depth to 0.5" to accommodate thread engagement (I've taken to using 'favorites' to make this easier on me when modeling). This isn't my entire problem, but it is a factor.

So these heat exchangers have 4 main connections (2 pairs) on them that will change size with the diameter of the exchanger. I thought I'd be clever in the design table and use the "HW@" property to make the changes. I also needed a way to drive the wall thickness of the boss surrounding the NPT hole. I'm not all that concerned about the actual thickness of that wall, I just need the hole to be in the right place, and the wall to look reasonably correct (in our assemblies, the look is kind of important, and the connection placement is very important, the rest is secondary). I created the circular boss, and then slapped the hole center point to the center of that boss. I then went into the sketch profile of the NPT hole and linked the thread width value (the largest diameter in the profile). I then created an equation that made the boss diameter 3/8" wider than the hole diameter.

After I got done patting myself onthe back, I switched configurations (and as a result - hole sizes) and promptly began chewing on shoeleather, the boss didn't update as expected.

I've observed the following:

1. Favorites don't seem to change with the hole size between configurations. Is there a way to do this? I've removed all favorites from these holes as a result.
2. The dimension value names in the hole profile sketches under the hole wizard holes are not constant through the configuration changes - so the linked values don't update when the holes do. This is what was causing the update issue with the boss that the hole goes into - it also (incidentally) makes the thread depth impossible to configure between hole sizes (found this out when I tried to configure that value instead of driving it with favorites).
3. SolidWorks seems to consider the hole feature the same between configurations (hence why the favorites don't change) but the sketches that drive them are all new (hence why the linked values stay the same as their original and thread depths get wonky).
4. The only way I can see that I'm left with to accomplish this is to suppress the hole each time it changes and create a new hole feature with the appropriate settings. This (IMHO) defeats a HUGE advantage of a design table - I can no longer drive geometry simply by changing the size of a hole, it has to be done manually... unless I am mistaken and there's some voodoo going on here that I'm not aware of (or could use to make it all work).

Any ideas?

Using SWX '08 SP5.