How do I make a molded part? 2

[Timelord]

I've been a SolidWorks user for a lot of years, but I have never had to make a part that is molded by other parts. I've now have an assembly modeled that gets potted after assembly and I would like to model the potting compound. I am familiar with the combine command, but it only seems to be available inside a part file. Is there anybody out there that does this on a regular basis that can tell me the most expeditious way to model the potting compound? A quick description of the method should get me started down the right road.

TIA,

Timelord

 

[MadMango]

Search SW Help for "cavities".

"Art without engineering is dreaming; Engineering without art is calculating."

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[CorBlimeyLimey]

What's wrong with using the Combine tool?

Create a new part, consisting of a simple block of the potting compound.
Insert the assy/component to be potted.
Combine to leave only the potting form.
Add that form to the assy/component to be potted.

 

[Timelord]

MM,
I looked at the help file for cavities and it seems to be set up for creating the mold from the part, not the part from an assembled mold. I saw nothing about doing the inverse of a cavity.

CBL,
Nothing is wrong with the combine command except it only appears to work in a part file. My "mold" is an assembly of a lot of parts and I cannot get combine to be active, even while editing a new part file created inside the assembly. How do you insert an assembly into a part file as solid bodies and keep it parametric? Also, I need to create the block of potting material from the inside surfaces of the cavity, starting with a simple block would be very difficult because of the complexity of the walls of the cavity.

Thanks,

Timelord

 

[dgowans]

Timelord,

Insert your part that represents the potting compound into your assembly.

In-context edit this part.

Offset the surfaces of interest from the parts that will touch the potting compound at an offset of zero. This will copy these surfaces into your potting compound part.

Untrim, Trim, Stitch these surfaces as necessary to obtain the final form of the potting compound.

Depending on how many parts / surfaces will be in contact with the potting compound, this can be a huge PITA, but it can be done.

 

[MadMango]

Timelord, your mold base part will be your potting material model. The cavity feature you insert will be created by the part models you select that will be covered with the potting material.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[acesup731]

Timelord,

You can throw a block into your assembly that is bigger than your assembled mold cavity but smaller than the outside edges of your mold. Then run the cavity command to remove all the edges of the block to make your finished part. It is actually pretty simple. Once you get your part mated into place, you have to just fix your part otherwise your mates will blow up when you run the cavity tool because the faces you mated to will be gone. The only way around it is to mate to the planes.

At my old job I used to do this all the time, but I don't have any examples now. I could throw one together, if my directions don't make sense.

 

[MadMango]

See attached, it might help. Cavity1 removed material for my ribbon cable that was being encased in the potting material.



"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[Timelord]

Thanks to all for the help.

Here's how I did it. I started a new part inside my assembly and then inserted a bunch of zero offset surfaces that defined the outside of the cavity to be filled. (thanks to dgowans) I then extended, trimmed and knit the surfaces into a solid. Then I used the cavity command to make holes in my part wherever there was a part imbedded in the potting material (thanks to MadMango) . Lastly I opened the part and did just a little trimming to eliminate some excess material in areas where the potting compound won't flow.
Sure do love this forum, way better than the SW sponsored forum.

Thanks to all,

Timelord

 

[acesup731]

I'm glad you got your part finished and in Solidworks there are many ways to accomplish the same thing.

As I said before you could have put a block into the assembly and used cavity to define the entire part and not had to mess with offseting, trimming, and extending surfaces, but each to his own. I just think the way I suggested would have taken about 30 seconds. I posted a simple example of what I am talking about. Maybe it can help you in the future.

Anyway, now you know some about surface modeling as well.

 

[rikonen]

I agree with acesup731 on this one, this is the appraoch I take as well and only takes seconds. All it takes is to place the blank block representing your material you want so it fits inside the molding area and edit the part, select cavity and then select all the remaining components from the assembly and perform the cavity feature, your done works great without all the added work needed in other methods mentioned.

 

[MadMango]

Just beware that you can only select other parts in the assembly to create your cavity features, not sub-assemblies.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of Eng-Tips Forums?