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Post by cplmickey on Mar 6, 2020 22:22:49 GMT
Just recently I seem to have been beset by problems with brand new drills. A couple of weeks ago 3 brand new 1/16 drills wouldn't cut and I found the tips hadn't been ground properly - essentially they hadn't been backed off (is that the right term) so the cutting edge was level with the entire end of the drill.
Last week I bought a 21.5mm drill for a hole in my fly cranks. The drill was so eccentric one cutting edge was about 11mm long and the other about 13mm long. In fairness, the company sent me another which I've just used tonight. However, the shank wasn't concentric with the drill so I had to drop it into the lathe first to sort that out.
Is it just me that's unlucky or are drills just generally poor quality these days.
Ian
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jasonb
Elder Statesman
Posts: 1,246
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Post by jasonb on Mar 7, 2020 7:34:27 GMT
Depends what you are buying and paying for. Not found problems with decent and even half decent makes but they do cost a bit more than cheapies.
I'd be boring the cranks after roughing out with a nominal 20mm or 3/4" drill rather than buying in an odd size.
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Post by cplmickey on Mar 7, 2020 10:10:10 GMT
I'd be boring the cranks after roughing out with a nominal 20mm or 3/4" drill rather than buying in an odd size. Yes I was all set to bore them but the drawings suggest reaming and so did the experienced engineers down the club so that's the way I've gone with this.
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Post by 92220 on Mar 7, 2020 13:02:42 GMT
I tend to buy my HSS drills from Kerjeng Model Engineering Supplies. They only sell British manufactured drills, which I understand have a slightly different geometry to the far eastern ones and therefore cut slightly better. British made HSS also seems to be a bit harder and holds it's sharp edge for longer. It may be my imagination but I certainly get on better with sharpening lathe tool steel that I have had from 40 years ago!
Bob.
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Post by cplmickey on Mar 7, 2020 22:41:20 GMT
I tend to buy my HSS drills from Kerjeng Model Engineering Supplies. They only sell British manufactured drills, which I understand have a slightly different geometry to the far eastern ones and therefore cut slightly better. British made HSS also seems to be a bit harder and holds it's sharp edge for longer. It may be my imagination but I certainly get on better with sharpening lathe tool steel that I have had from 40 years ago! Bob. Didn't know Terry was still in business. I've passed his house only 30 minutes ago. Must make contact again. Ian By the way, I've been getting my drills from UK Drills over Manchester way so I assumed they were British made HSS.
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Post by 92220 on Mar 8, 2020 18:48:18 GMT
Hi Ian.
Yes Terry is still in business but only mail order. He has stopped showing at exhibitions.
Bob.
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