Shell cutting End-mills

[Wal]

Hello all,

I'm tooling-up to run a couple of profiling/pocketing tests on some mother of pearl - think intricate inlays that you find on custom guitar fret-boards. Here's an example of the kind of shapes I'm hoping to cut - in the clip I'm using a 0.2mm 2-flute end-mill and the material is perspex:



And the circled area in the pic below should give you an idea about the pocketing that the 0.2mm end-mill will have to do:



Clearly, the feed-rates I'll use cutting the mother of pearl will be a lot slower than what you see in the clip above - what concerns me most is the longevity of the end-mill and I'd just like to see what your opinions are on the options I have.

1. The 0.2mm end-mill I used in the clip above didn't last long - it could well have been feed-rates, the perspex packing into the flutes etc etc. but it was also a cheap piece of tooling (£7). Maybe try it again at lower feeds actually in mother of pearl..?

2. What I'd really like to try is one of these:

http://www.precisebits.com/products/...bits/shell.asp

3. I contacted the supplier I usually go to for my tools and they suggested 2-flute blue coated carbide at around £30+VAT a-piece, but as far as I can tell, this would just be a generic 2-flute for harder materials, but none of the features (ie. fishtail) of the cutter available from the States.

So what do you reckon? Persevere with the cheap-o cutters? Try the expensive conventional cutter, or just buy a few of the end-mills designed for this type of work from the US..?

Thanks for your thoughts/advice.

Wal.