Hole size between inner and outer shell

Hi all, I just got a white detail model rejected with the message: "internally hollow but no acces to remove support, do as a solid part or in SLS with 1mm wallthickness." It came with this image:



The circled bits are the holes between the outer and inner shell which I put in to remove the support material. I'm assuming that the problem is they're too small to drain the whole model as the holes are only 1.7mm in diameter and are in the feet, while the model is about 10cm tall.

Below are pics of the inner shell and the whole model.

Inner shell:


Outer shell:



So, the question is how big and how many holes should I put in, and where do you think they should be?

This is my first model so any suggestions would be greatly appreciated.

Are the holes joined up to make a tunnel?

yep. The mesh is manifold, and the normals are pointing in the right directions (at the air inside and out).

What's the wall thickness?

0.7mm. Which rereading the material sheet is too thin for white detail. Doh.

Might be good for WSF. I have Nancy on the case of drain hole requirements.

Well, thickening it up and putting in a couple more holes won't hurt it and only takes five minutes. I kind of want to test out as many materials as possible with real models and have one with moving parts I'm working on now for my first WSF. Not too distressed as looking at the model again there's a couple of areas which could still use some work anyway. Hopefully Nancy will come back with some info as I'm going to be doing quite a lot of these kind of sculps. Cheers for you help!

Have you thought about going with a solid model for FCS? or even just plain sandstone.

Fixed your last image for you.

I might try that at some point. The only issue with the sandstone is that I reckon the tail and legs on the cat might be a bit delicate. I've got a couple of other ideas for models that would probably suit sandstone better. Also I like painting models in real life more than in the computer!

Those are my near term goals. Sandstone and Ceramic. I've also been thinking about painting them myself to add that personal flair to it. Then I'll have to find something to coat it with to make it stronger.

I'm aiming to work up to some increasingly complex automatons, so WSF is probably going to be my material of choice. I just fancied seeing what the others were like. Anyway time to sign off for the night, I'm knackered. Cheers for the help.