Wierd "lip" added in a Rotational Cut

[sparkfun]

Greetings,

I am currently trying to add a rotational cut to create space for an o-ring on a part. No matter how I attempt to remove the material (rotational cut or a sweep) a little "lip" is created.

View attachment 2952

You can see the "lip" I am talking about on the left of the semi-circular post.

I also tried a normal extrusion cut (after the revlove) to see if that would cut this thing out -

View attachment 2953

but for some reason ProE still sees this. This part is to be rapid prototyped and when I save it as an .iges file the lip still shows up. Blah.

Any thoughts on how to rid myself of this little pest? Thanks. Oh, and Im using WF3.

 

[mgnt8]

what does your section look like - maybe something is mis-aligned. If its a half circle, try to use a full circle, but there's not much I can tell you without seeing the model. I can say that if the lip is small like .006" or less, there's next to no chance it will build if your talking about SLA or SLS.

 

[PRStockhausen]

You may be able to get rid of the lip by changing your accuracy.

 

[sparkfun]

Mgnt8 - thanks for the assurance that theres a good chance this lip wont show up on a SLA. I think we'll go ahead and have that done but Id still like to know what causes this to happen...just bugging me ya know?

I tried all sorts of different ways of drawing the cut but nothing changed. I also increased the accuracy but that was no help either.

Here is the file, if you have a chance to check it out Id apprecieate it-


2006-12-26_141851_endcap_solo_14_xii_06.prt.zip

 

[jeff4136]

Please state the version used (WF3?) to create posted files.


I can't see much in the (a little dark) pics but problems
of that nature are usually due to an inability to create a
'good' trim line when doing the boolean subtraction.
Creating the void body as a surface feature and manually
creating intersection curves might give you an indication,
either visually or when a curvature graph is shown. Best
bet for a cure is to simply make sure the void body extends
well outside the solid body (unless there are other
problems as well; any goem checks?). Determining
coincidence can be difficult for the system under a variety
of conditions.


On the subject of accuracy; you can read the resolution in
neutral translation files and it's sometimes a good idea to
do so, especially if you have a datum point or some other
geometry causing a way big part bounding box. Holler back
if that's of interest and you need more info.

 

[dr_gallup]

Your part is behaving exactly as it should. Your cut is intersecting the posts exactly as you defined it. If you want to cut the posts completely you need to change the section of revolve1 so that it extends closer to the axis of revolution.
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