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Creating negative impression of another model?

Creating negative impression of another model?

Creating negative impression of another model?

Salutations all!

New to the forums and to Creo, but I've got an interesting dilemma. Recently I've been tasked with taking a Creo model someone else has designed using freeform surfaces, and creating a 3D printable part that has the negative impression of the outside of the model so it can interface snugly to the exterior of the pre-designed part.

Unfortunately the model I've been given consists solely of one import feature, and nothing about it seems to be editable or workable on my end.

My first instinct was to try and take this model and do some kind of occlusion cut on a solid block, but I can't figure a way to make that happen.

Also of note, I don't have access to the style option for working with surfaces, so I don't know if what I need is hidden in that package either.

Appreciate any help that can be afforded

RE: Creating negative impression of another model?

Almost certainly the simplest approach is to create a mesh from what you have and then use a mesh-editor to create a mesh suitable for 3D printing. Example: MeshLab.

There may be a module from PTC that could do this more easily, but the base of Creo isn't it. It looks like that maybe "Design Advanced Plus" might, perhaps, could be, with the functions you need.

Look on the PTC site for the software support pages to see how the software is supposed to work for any functions you consider buying.

It may be worthwhile to contact Bart Brejcha at a company called Design Engine who does this sort of work and gives training to do this sort of work. If there is money involved in getting this task done, that's who I would start with.

RE: Creating negative impression of another model?


Oh, and just to reinforce my, umm, lack of confidence, in their brochure PTC apparently calls it "Design Advanced Plus" but on the overview page that links to that brochure it's apparently called "Design Advanced Professional" which then links to "Design Advanced Plus" titled page. Maybe you can get a separate license for "Interactive Surface Design", aka ISD.

One thing that 30+ years of PTC has done nothing to improve is consistency in marketing and message. They use pale gray on pale gray for low readability (https://www.ptc.com/en/products/creo/packages). They cannot stick with a product name from one page to the next much less one generation to the next.

While I have pity for the users of other software, PTC makes getting their software hurt so much it's no surprise competitors got a foothold.


RE: Creating negative impression of another model?


Quote (3DDave)

One thing that 30+ years of PTC has done nothing to improve is consistency in marketing and message
Glad I'm not the only one who's been confounded by their naming! I'm on Creo 4 right now and trying to explain which packages I'm missing has been a mess.

I'm definitely leaning towards trying to do a quick workaround in another program now. The design is a one-time project so it would probably work out in everybody's interest if I just made the negative impression it's own STL or otherwise, then import into Creo and do the more important dimensional work adding on from there

RE: Creating negative impression of another model?

PTC has announced new naming for their bundles, doing away with the Plus and changing to Professional.

"Wildfires are dangerous, hard to control, and economically catastrophic."

Ben Loosli

RE: Creating negative impression of another model?

You should be able to put your block and this other part in an assembly and do an intersection which will cut it out of the block.


The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Creating negative impression of another model?


Do you know where I'd go to define that intersection? The only option I see is the intersect modifier which I can't select for the models.

RE: Creating negative impression of another model?

In a part, could you simply offset surfaces (at 0) from freeform, merge and build opposing model from that?

RE: Creating negative impression of another model?


I'll have to give that a try. I ended up not designing around the negative for the model, but if it can be done it would be good to know.

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