PROBLEM, HOW TO - open up an inaccessible hole in 10mm s/s?

[Scotty_Tradewind]

thanks for the effort Will'

S.

 

[30boat]

Many years ago I had to open up - by a millimetre or two - the 3/4" holes for keelbolts in 1/4" stainless steel floors which I had just embedded in the floor of my Westerly. After some experiment I found that the best solution was a fluted tungsten carbide slot milling cutter in a die grinder (for those who don't know, that's an angle grinder without the angle). It worked a treat and cut the stainless like butter, though I got a bit enthusiastic and melded the braze holding the first cutter to its shank. Ping. After that I went more slowly, using coolant and frequent rests, and it all went just fine.

Unfortunately I don't think this would work for the OP because of the length of shank he'd need.

If the flukes were brazed on I would say that what you were using was a router bit not a milling cutter.These are made of solid stock in severeal material ,tungsten carbide being one.