- Thread starter knoba
- Start date
Knoba,
Interesting table. I did a quick calc, based on HSS cutters with a peripheral cutting speed of 100 feet/minute (about right for HSS cutting low carbon steel). Your table is pretty much spot on.
Now - look at the magnetic drills on the market, take the Evolution ME3500 for instance which - they tell us - is rated for cutters up to 35mm. The drill runs at 550rpm - over twice the speed shown for that size cutter in the table. Oops. Probably ok for a 16mm cutter.
A 35mm cutter will have a tip speed of 200fpm - handy if you're boring a hole through brass, but you might find the magnet's not sticking to the work too well.
Or - buy carbide tipped cutters - they're ok to about 250fpm on low carbon steel.
Ian
Interesting table. I did a quick calc, based on HSS cutters with a peripheral cutting speed of 100 feet/minute (about right for HSS cutting low carbon steel). Your table is pretty much spot on.
Now - look at the magnetic drills on the market, take the Evolution ME3500 for instance which - they tell us - is rated for cutters up to 35mm. The drill runs at 550rpm - over twice the speed shown for that size cutter in the table. Oops. Probably ok for a 16mm cutter.
A 35mm cutter will have a tip speed of 200fpm - handy if you're boring a hole through brass, but you might find the magnet's not sticking to the work too well.
Or - buy carbide tipped cutters - they're ok to about 250fpm on low carbon steel.
Ian
knoba
...break a leg!
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Thank you v. much for confirming the speeds! They "seemed" good to me and I take it these rpm's are also suited for bi-metal hole saws too ? / !
It really winds me up that most of the drills, on the market today, are not really suited for metalwork jobs. Even my pillar drill only goes down to 180 rpm, and consequently, fried a 50mm starrett hole-saw on stainless steel the other day. I guess the manufacturers want to make us buy bits & cutters that are disposable! The bit that really nags me is that it's the quality of the job that suffers.
I want to make things better, not necessarily quicker. 
It really winds me up that most of the drills, on the market today, are not really suited for metalwork jobs. Even my pillar drill only goes down to 180 rpm, and consequently, fried a 50mm starrett hole-saw on stainless steel the other day. I guess the manufacturers want to make us buy bits & cutters that are disposable! The bit that really nags me is that it's the quality of the job that suffers.
I want to make things better, not necessarily quicker. 
jugs
Dont wish to offend & annoy, but...
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Thank you v. much for confirming the speeds! They "seemed" good to me and I take it these rpm's are also suited for bi-metal hole saws too ? / !
It really winds me up that most of the drills, on the market today, are not really suited for metalwork jobs. Even my pillar drill only goes down to 180 rpm, and consequently, fried a 50mm starrett hole-saw on stainless steel the other day. I guess the manufacturers want to make us buy bits & cutters that are disposable! The bit that really nags me is that it's the quality of the job that suffers.
Yes, the teeth are HSS, but drop the speed 10% & saw will last longer.
Totaly agree with you.
jugs
Dont wish to offend & annoy, but...
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Hmmm.... it's often struck me that; you're, quite possibly, the smartest man alive Jugs!
"How true", he said modestly as he ran his fingers through his tousled locks. while'st gazing at the reflection of his finely honed muscular body in the plate glass window of MENSA, where he had just been assessed with an IQ of 450.
(this was immediately before walking into the lamp-post)
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"How true", he said modestly as he ran his fingers through his tousled locks. while'st gazing at the reflection of his finely honed muscular body in the plate glass window of MENSA, where he had just been assessed with an IQ of 450.
(this was immediately before walking into the lamp-post)
What makes me think this was written by Mrs Jugs
jugs
Dont wish to offend & annoy, but...
- Messages
- 1,449
Hmmm.... it's often struck me that; you're, quite possibly, the smartest man alive Jugs!
"How true", he said modestly as he ran his fingers through his tousled locks. while'st gazing at the reflection of his finely honed muscular body in the plate glass window of MENSA, where he had just been assessed with an IQ of 450.
(this was immediately before walking into the lamp-post)
What makes me think this was written by Mrs Jugs
No it was john, just reporting 'the facts' as he sees them, (but he is demented
). 
jugs
Dont wish to offend & annoy, but...
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Hip is doing very well, thank you Knoba. I'm getting around pretty well, although still have to be careful about bending forwards, or sitting on low seats etc for the next few weeks. Horror stories about new hips 'popping out' are a good incentive to obey.
It's very useful to have John to put on my elastic stockings (to be worn for 6 weeks) and to hose me down in the shower. I've refused his offer to stand in the yard and be pressure washed - perhaps if it was warmer?
ps his nursing duties are not going to be over for a bit, as an angiogram has shown I need triple? by-pass surgery!
It is difficult to believe I look and feel quite well! Regards Jan
are a good incentive to obey. It's very useful to have John to put on my elastic stockings (to be worn for 6 weeks) and to hose me down in the shower. I've refused his offer to stand in the yard and be pressure washed - perhaps if it was warmer?
ps his nursing duties are not going to be over for a bit, as an angiogram has shown I need triple? by-pass surgery!
It is difficult to believe I look and feel quite well! Regards Jan
knoba
...break a leg!
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- Sussex, England
Well done for taking it easy. I know it's difficult when you're forced to for a spell, but... you're worth it! It's also a good opportunity to get in plenty of treats (for both of you) and indulge in lots of that "best medicine in the world" (laughter ). You'll be rocking 
down that disco in no time at all. 
It's also a good opportunity to get in plenty of treats (for both of you) and indulge in lots of that "best medicine in the world" (laughter ). You'll be rocking down that disco in no time at all.
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- 23,771
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- Birmingham
Is this some scheme to improve his manly figure or does he just like wearing your clothes?
