Drilling stainless steel

[raro3]

Thanks very much for all the advice, which has been duly noted.

Screwfix have told me they only sell cobalt drills in sets, but have suggested a DeWalt Extreme drill bit

http://www.screwfix.com/app/sfd/sea/sear...earchText=32213

Any experience anybody?

Cheers, Phil

 

[VicS]

Cliff can I had to your excellent advice that centre punching too enthusiastically can work harden stainless making it difficult to get started. Or do you disagree? If the job can be clamped to the table of a bench drill then centre punching should not be necessary.

However it is not clear from the original question if the chain plates and backing plates are to be removed or drilled in situ. If the latter, as assumed by Ian Simpson, then much of the advice about bench /pillar drills will not be applicable. 18 holes to enlarge from 6mm to 10mm (or a bit more for clearance) will be a slow tedious job by hand. If they are to done in situ then hiring a slow but powerful industrial hand held machine may be the way forward.

A jump from 6mm to 10mm seems very large. Would not 8mm be big enough? Or are we talking about a very big boat?

 

[cliff]

Fully agree - a small pop mark - just enough to keep the pilot drill from walking - is all that is required although in the case in question I believe there is already a 6mm hole to start with. Trying to hammer the center punch through the material will effect the hardness and could lead to broken bits.
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"Artificial intelligence is no match for natural stupidity"
sailroom <span style="color:red">The place to auction your previously loved boatie bits</span>

 

[cliff]

Try axminster power tools here - item no 400157
--------------------

"Artificial intelligence is no match for natural stupidity"
sailroom <span style="color:red">The place to auction your previously loved boatie bits</span>

 

[William_H]

OK Ok so I was known as RAGS in my trade training days. (Rough as Guts) I still reckon if you have a little time and patience and a whole lot of Scottish heritage then have a go at drill sharpening. I am far too cheap to buy new drills especially in the larger sizes and I do drill SS a fair bit. (But not commercially) luv to all olewill

 

[Andrew_Fanner]

I'm a firm believer in drill sharpening, there again, I have a drill sharpener. You can enlarge holes in stainless using a tapered hand reamer, then all you need to do is get the initial pilot hole drilled. Tapered reamers come in full taper and stepped versions where each step has an initial taper and then a parallel section to ensure that the hole has parallel sides. But: they can be a beggar to get hold of. The very keen, or desperate, could make their own. One of those scenarios where, if you have the kit, you probably can make one, but may already have one. You can't borrow mine, its somewhere in the mud in Mill Rythe:-(