Methods / tools for TUNNELING into silicone?

Good morning! Last night I cast some fingers for a monster hand and realized I made my approach more difficult than was necessary. I'm hoping for a little advice on correcting the issue.

So I sculpted these fingers onto a plastic mechanism, in such a way that the fingers line up with one another in a really specific arrangement. Imagine each clay finger as a sock or a sleeve; it slips over the underlying mechanism in a specific way.

I made a brush on + mother mold of the whole hand (with all of the fingers attached). 

I then dug out the clay from my brush-on mold and cast a single piece in silicone.

The fingers themselves look great! The problem is that they are solid silicone. Getting them to slip over the underlying mechanism is proving tedious; I slice off little bits of silicone with an exacto knife, then do a test fit.

Do you know of a good tool or trick for TUNNELING into silicone? I am basically slicing a squared little tunnel into each finger. This has been very slow and kinda uneven.

So far, I've found the best trick is to slice deeper and deeper into the finger so that I'm basically cutting a single carrot-stick-shaped cube of silicone. It is a lot cleaner and easier than snipping tiny bits one at a time. The only problem is that once you remove your big carrot stick piece, subsequent cleanup or widening of the tunnel is tricky.

Thanks in advance for any feedback! 


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    Hi Dan,

    That's a tricky one.  I would try making a silicone drill.  Take a piece of brass tubing and carefully sharpen the edges on one end.  You can can twist it into the silicone by hand, or chuck it into a drill and it should core out a section.  If you are not going all the way through the piece you would still have to cut the plug out, but it may help.

    Best of luck!

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    Good idea Chris, thanks!
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