Merge Operation Error: One-Sided Edge

[sallyhoo84]

Hi,

I'm using the merge operation for the first time and am getting the following error message: "WARNING: One-sided edge found in MERGE. Could not intersect part with feature."

I am in assembly mode with the two parts to be merged. One part has a counterbored hole and the other part is a hole insert to be welded inside that hole. The ID/OD are the same and assembled together through an insert constraint and the bottom surface of the insert is mated to the counterbore surface.

Does anyone know what the error message means? Am I using the merge operation incorrectly?

Thanks,
Saly




Edited by: sallyhoo84

 

[design-engine]

check to see if accuracy is set the same on each part.
Edited by: design-engine

 

[sallyhoo84]

Sorry, in checking the accuracy, I realized I was mistaken before... the ID and OD were off to produce a clearance of 5 mils. Is that the reason for the error (keep in mind, I still do have the flat mating surface so it's not like the insert is just "floating" in that hole)? If needing more than one intersecting surface is in fact the reason why I get that error message, are there any recommendations for a better way to approach this?

 

[design-engine]

Merge should give a little problem with coincident surfaces. If they are not touching at all then there will be a problem for sure.

 

[CRang72]

Did you check the relative part accuracy for each part, as design-engine suggested, or did you just verify the ID and OD values? Go to Edit > Setup > Accuracy to check the relative part accuracy for each. It may help to change the default value of .0012 to something like .0001 as well. I've had to do that for some features to work correctly.

 

[dgs]

You'll need to change to absolute accuracy instead of relative. A relative accuracy value is a ration that is used to calculate an absolute value based on model size. The same relative accuracy value in two parts will result in two different calculated absolute accuracy values Explicitly setting it to absolute produces the exact same accuracy in both parts.

 

[CRang72]

Thanks for clearing that up, Doug. I guess I've only changed the relative accuracy when I've had problems with featuresat the part level.

 

[dgs]

I only use absolute accuracy because I've run into issues with relative. I've been doing this for 12+ years. My understanding is that the default is changing from relative to absolute in WF5, but that's speculation based on a vague relocation of what someone else said somewhere.

 

[sallyhoo84]

Thanks guys, both ways worked. The only difference (as I saw) was that with relative accuracy I didn't get the "support associative placement" message whereas with absolute, I did.