Hello,

I've created a couple of models which I need to convert into STL solids to be able to manufacture parts.

The attached model is a rather simple example.

How can I convert my models into solids?

S.

Hello simba,

Your model is not symmetrical, that is why you have a gap between the wing and the fuselage. You might want to work backward a bit to see where your mirroring went wrong. Otherwise you could Trim your model in half, Mirror the half and Join the result into a solid.

Hi Simba, you can use the Edit > Join command to glue together surfaces which are touching at common edges:




Join will only glue together edges that are not already joined between 2 surfaces though, so for your case here you already have some planar faces sealing off the sides of the body piece, you will want to delete those faces first before you will be able to join the wings onto them, here are the ones I'm referring to:



Once you have removed those you can then join the touching pieces together (it seems that one wing was slightly moved out of place, I moved it back).

That will leave you with a joined object that is almost a solid except not quite because it has some remaining openings at the ends here:




In order to make a solid those remaining openings need to be sealed off with surfaces that are are also joined in, for planar openings like that there is an easy way to do that by selecting the whole object and running Construct > Planar, that will build planar surfaces over those openings and join them in and the result of that will be a solid. I've attached a model file where I've done these steps to solidify your object.

So the basic process to have a solid is to have all the surfaces joined at common edges to form a "watertight" skin. For other types of objects it can be convenient to keep things as solids from early on and use booleans to carve pieces off and just keep working with a solid all the time. If you're going to be done some fancy surfacing then you'll mainly need to use Edit > Join to glue together the surfaces in order to make a solid result.

There is a script that can help you visualize what areas of your object are still open by highlighting the unjoined edges in it, see here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=6051.2

That can help a lot so you can see what specific area still needs work, once you set up that script from the above link then you push the N key and all the "naked edges" (edges that are a boundary of just one surface instead of joined between 2 surfaces) will highlight.

Hope this helps!

- Michael

Hello Michael,

with one exception it would be best for me if I could set "solid at all times" in combination with sweep and blend and work with booleans. Is that possible? Maybe I missed a basic setting?! There's only one hollow/surface part in my design. I tend to work/end up with a mix of solids and surfaces.

Some of my 'boolean union' attempts lead nowhere after 15+ minutes processing time in order to create a solid part for machining purposes (on a current i7 with 32GB Ram).

S

Hi simba,

> with one exception it would be best for me if I could set "solid at all times" in
> combination with sweep and blend and work with booleans. Is that possible?

It's possible to generate a solid directly from a sweep if the profile you are sweeping is a closed planar profile curve. There is a "Cap ends" option that by default is one that will generate a solid sweep object with planar end caps on it.

Not every kind of model is amenable to working in that way though, if you have more fancy swooping surfaces as part of the model, it becomes more likely that you'll end up working at an individual surface level. When you work at that level you will need to use Edit > Join to glue the surfaces together to form a solid. If it is possible to do so it can be more convenient to work with solids earlier on in the modeling process.


> Some of my 'boolean union' attempts lead nowhere after 15+ minutes processing time in order
> to create a solid part for machining purposes (on a current i7 with 32GB Ram).

If you can post an example file where you're having that problem I'll take a look at it and try to give some advice.

One thing is that the boolean operations are mainly meant for cutting objects with one another, they try to intersect surfaces with each other and remove material. If you have all surfaces that are touching edge-to-edge and you don't need any material to be removed, you should use Edit > Join instead of boolean union to glue the pieces together. Join does not attempt to intersect pieces with each other or remove any material, it only tries to glue edges to other edges.

- Michael