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aproximate copy of SURFACES

tobbo

Member
Is there any way you can copy a couple of quilts to get a single quilt surface? (like when you copy some curves, and pick approximate and get just one curve) .

I found that you can make a copy of a couple of surfaces, use offset and under "options- special handling" set the quilts to be apporximate and get a result that is "one single surface". The problem there is that i have to set a value for the offset , it cant be "zero" (and also that it behaves a little funny sometimes) .

So, is there a way to get an approximate surf? Or just a way to connect quilts to be one single quilt.

//Tobias

Ps, the reason i want to do this is because when i´m patterning something that goes over a few quilts, it sometimes becomes very unstable and may fail if the quilts changes shape...
 
I just tried with two quilts (two surface extrusions that are tangent at connections) and joined them using the merge command. Then if I create a datum point and right click until the whole joined quilts are selected, I can place the point and it "moves" freely on both surfaces.

Oh and I'm on Creo 3.0
 
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Thanks! And yes, since you put your point on a quilt, and not on a single surface patch you can move the point around :) . What happens when i try to pattern on a quilt that got several patches (made out of several surf features) is that "sometimes" it works , and sometimes it just dont. The thing i found is that if the feature/geometry that i try to pattern ends up near, or right on an intersection of several patches (like on a vertex) it will "sometimes" fail. (just like when you model something, even solid, and get a distance/edge thats to small so you have to change accuracy to make it work... i.o.w , nothing wrong with the geometry, it will just fail unless you change something, but the accuracy does not seems to be the problem here.) So, to get rid of the vertex/intersection issue I figured that if i could make an approximation of the quilts , the resulting surface would be good enough to use for patterning , especially since it wont have any intersections!

I can get creo (3.0) to do it by using offset and use approximate , but i cant set the offset distance to 0.

//Tobias
 
interesting! Can you actually set an offset value to Zero when using approximate in offset?

Please look at the attached file. Resume all the features - edit definition on the last feature (offset) and set the offsetvalue to 0. When "there is a value" , creo creates a surf but when I set it to 0 , the surf disappear.

//Tobias
 

Attachments

  • surf.prt.1.zip
    86.2 KB · Views: 7
Btw, If I dont use approximate, i can set the value to 0 and get a surf :)

(creo 3.0 M070)

//Tobias
 
You don't see the surface but the feature doesn't fail so I think the surface is still there... Probably when offsetting by 0 the approximate and actual surface are the same, therefore you still see patch lines. Maybe in this case the result is the same as if you "merge".

Crazy idea: have you tried offsetting your approximate surface back of the same quantity, but opposite direction? It works but I have no idea is the end surface is correct or not...
 
i agree, it´s a mystery where the surf is when setting the value to 0, and why the feature doesn´t fail when there is no visible resulting surface. I actually don´t think the approx, and the (in this case) copy surf has got the same geometry. (since then i wouldn´t be an approximation :) )

Regarding the crazy idea, I like how you think! And yes i tried that and "it works" (sometimes) , especially in the part i uploaded it works just fine! The result of the "offsetted approximated offsetsurface" is what i´m looking for! But when i do that in a more complex surface, and when the approximation surface is in fact an approximation, the offset "back to the start position" will be too way off the start geometry. (btw , An option that would let me set the value of difference for the approximation would be even better, but first i have to figure out how to get my single patch surface :) )

/Tobias
 
I have seen that when offsetting back to start position, the created surf will offcourse not be exactly the same as the start surf since it´s an approx, And i can live with that. It´s just that it cant be tooooo much difference. :)

//Tobias
 

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