Having Trouble Sculpting Surfaces into a Solid

[Anonymous]

I have a 3D drawing for an object I intend to have 3D printed currently made from surfaces stitched together.  I have managed to turn most of these surfaces into solids, but whenever I try and use the sculpt command for the top of the object, it gives me varying errors as to why it doesn't think the enclosed region is watertight.  More often than not I get "Inconsistent information in vertex and coedge attributes." but recently it has been saying "Operation did not add or remove material." and I'm frankly at a loss.  I have done my best to scour the drawing for holes in my surface setup, but I honestly can't find any.  If anyone has any thoughts on how I can either get around this issue, or make Autocad happy with me, by all means let me know.  The drawing is for a Small lid that will be used on a device my company is producing, nothing too fancy.  

Thanks

[john.vellek]

Hi @Anonymous,

I would love to see your final when you have it done.

[Anonymous]

@john.vellek

If the surfaces and solids overlap a small amount, will I still be able to sculpt the final piece once all the gaps are covered?  I can't get the sweeps to align perfectly with the top and bottom, and I'm starting to think I may need to rethink the curved edge overall in exchange for something a bit simpler to work with.

[Anonymous]

@john.vellek

John,

I have been having issues getting the straight segments to contact both the top and bottom edges and thus I am getting increasingly worried that I will end up with the same issue I started with, namely not being able to sculpt surfaces into one solid object.  I am starting to think that this method will not really work out and would be willing to compromise the filleted edges in my design if I had a different way to guarantee that is would be a part of a constant thickness that could be easily 3D printed or injection-molded.

Thanks

[john.vellek]

Hi @Anonymous,

Let me take another look at this for you. What do you want the fillet radius to be set at?

[Anonymous]

@john.vellek

Ideally 0.1", that would look the smoothest considering the size of the piece.  

Thank you for your assistance!

[john.vellek]

Hi @Anonymous,

OK, 

I will try this again time permitting.

As you saw from my model, the construction can be simplified quite a bit from where you started.  The model I gave you is based upon your geometry still and there are errors because of it. Things are not perfectly straight and don't line up which is why this has become so difficult.

Let me see if i can make this work and I will post back.

[Anonymous]

@john.vellek

Here is the original file I mentioned to you.  The main point of the project was to increase the overall width by a quarter inch on each side and to add a small bar across the hinge points to act as a lid stop.  It is all one cohesive solid so hopefully this will be a better starting point.  

Please let me know if you'd like anything else from me and thanks for your assistance.

[Anonymous]

@john.vellek

Original solidworks version.  Note that the two pillars under the lid are in a different spot than on the autocad version, this is incorrect and was changed in Autocad.

Thanks

[john.vellek · Accepted solution]

Hi @Anonymous,

Here you go finally!

Even the original file had some funky things going on. I started in AutoCAD with a section plane that had a jog to include the posts inside. It rapidly became too cumbersome so I moved into Fusion 360.

I apologize for taking so long but I hope this helps. I strongly urge you to try Fusion 360 for this kind of process.

Please select the Accept as Solution button if my post solves your issue or answers your question.

[Anonymous]

@john.vellek

Thank you so much John!  You've really saved my neck with this one.  I will certainly take a look at Fusion 3D, I noticed that free trials are an option, and bring that option up to my supervisor for the future.  

Again, thanks for all your assistance.  

[dieters]

First of all, my compliments to John for a superb job!

I thought it would be helpful to add some tips on 3D solid modeling based on my experience with AutoCAD and include few files.

1. Create orthographic profiles in 2D, use the BOUNDARY command to turn them into single closed objects

2. Create wireframe reference geometry for sanity checking--always check and recheck distances! 

3. Set DELOBJ to 0 to retain all source objects, and put them on one or more Reference layers.

4. Move and rotate the 2D profiles into place.

5. Extrude, sweep, or revolve the profiles as needed (I rarely use primitives).

6. Apply Boolean operations--I use INTERSECT and SUBTRACT the most.

7. Delay UNION for things that might need to be moved later, save FILLET for the end.

8. Use GROUP to associate objects that you don’t want to Union--assemblies

9. Create blocks from repetitive objects to reduce DWG size

10. Save a version of a model at each stage so you can easily revert.

11. It's usually easier to recreate a sub-object than modify it. That's why you always keep your profiles.

12. Use HIDEOBJECTS and UNISOLATEOBJECTS to temporarily hide things from view.

- For box-like parts with a draft angle, create the profiles with the draft angle as shown in one of my attachments.

- Create an interior air-space volume that you can subtract from the exterior shape. Shelling also works.

Best wishes,

Dieter

[john.vellek]

Hi @Anonymous,

@dieters has some excellent pointers in his post. Since you were working with an existing model (that is not really built all that clean) this certainly presented problems for the both of us.

So in addition to his list and the things we worked through on this exercise, you might also take a look at the Autodesk App store for add-ins that might simplify part of the modification and rebuild of your models if you elect to stay inside AutoCAD.  I see there are some apps that will let you slice and even "peel" your models apart and this might be most useful if you need to work on them continually.

Thanks again for your patience on this issue.