Ship in a bottle

I've posted several questions in the last couple days regarding the wax support of the TP and FD/FUD plastics because I'm currently designing a ship in a bottle, where the bottle would be the solid plastic with a hollowed out ship inside, where the wax would be entrapped.

I've come to understand, from reading around, that the team at shapeways will pass my design if they realize that this is what I'm intentionally trying to do. How would I communicate across to them that I intend for the wax to be inside the model? Else they'll reject the design. I seems pretty apparent though, haha.

I've attached an unfinished photo so you know what I'm talking about. And some people have said that it's against regulation to have the wax entrapped, yet I've seen several models printed where that's exactly the case.

Hi!

I know Matthew our Engineer has given you some feedback on your particular design, so I'll just address the general rules for FUD.

Our guidelines are here:

https://www.shapeways.com/materials/frosted-detail-design-gui delines

and they state that we recommend TWO 2mm escape holes if you are designing a hollow model, so the wax (that we use as support material) can escape easily.

However, though it is not stated, we do allow you to make trapped materials like this design if your design makes it clear that is your intention.

This means leave absolutely NO holes if you want the wax to remain trapped (and create a ship in a bottle effect).

We will be updating the Design Guidelines soon to make them clearer, but hopefully for now this will be helpful!

Natalia

Then no support material will be used. Catch 22.

Thanks, that answers alot of my questions but is what he says true about there being no support material used if there are no escape holes? That seems to go against everything I've been told, haha.

Natalia will need to update this.. there MUST be micro-hole(s) between the inside and outside shells, or the inner shell is removed by Mesh Medic.

From experience, if you leave a 1mm hole, it confuses the operators - they're not sure whether you wanted it cleaned out or not. A tiny hole such as 0.01mm is sufficient to connect the inner and outer shell, and to trap the support material.

Thank you for bringing that up, it surely has saved me a lot of strife. I made the hole at the size you suggested, and I can tell that it worked due to the price dropping slightly.

Another thing I'm curious about is how small I can make details. Due to it being inverted, I would assume that the wall thickness rules wouldn't exactly apply to hollowed out gaps.

:facepalm:

That is what (I) get when I hit reply and then leave for the day without double checking my facts.

Stony is correct, tiny holes like 0.01mm in the models are what you need for the ship.

So to be clear, either put two LARGE 2mm holes in your model to have it hollow and free of wax
OR
One TINY 0.01mm between the inner and outer shell to make it clear you DO want to trap the support wax.

Thank you Stony!

Natalia

Using my Skull in head as an example,



The gap between the teeth, 0.18mm is just visable, the 0.32mm gap between the teeth & jaw is quie visable, and the detail of the teeth is more or less lost.

Paul

Some of my dimensions are much smaller than that, I wonder if it will be rejected or just printed as is