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Drill all drills
I have just watched a prog on digital tv (Ideal world) and they were
demonstrating a drill set that can drill through wood, plaster, brick, concrete, tiles, mild steel, cast iron and bricks. See www.idealworld.tv They were saying that they were a tipped drill and the tip was cryogenically frozen cobalt. Now I have been around drills all my working life and I can't understand how a drill can keep an edge on these materials. They did demonstrate what would happen with this drill, compared to a carbide tipped drill, by pushing it tip first into a normal carbide grinding wheel. Their drill formed a groove in the wheel, the carbide tipped drill had its tip ground back. Has anyone come across them before? Dave |
Drill all drills
Dave explained on 20/12/2009 :
They did demonstrate what would happen with this drill, compared to a carbide tipped drill, by pushing it tip first into a normal carbide grinding wheel. Their drill formed a groove in the wheel, the carbide tipped drill had its tip ground back. Dunno if they are actually any good, but.... Any form of carbide will make a groove in a normal (gray or white) grinding wheel. A green wheel is needed to sharpen carbide. -- Regards, Harry (M1BYT) (L) http://www.ukradioamateur.co.uk |
Drill all drills
In an earlier contribution to this discussion,
Dave wrote: I have just watched a prog on digital tv (Ideal world) and they were demonstrating a drill set that can drill through wood, plaster, brick, concrete, tiles, mild steel, cast iron and bricks. See www.idealworld.tv They were saying that they were a tipped drill and the tip was cryogenically frozen cobalt. Now I have been around drills all my working life and I can't understand how a drill can keep an edge on these materials. They did demonstrate what would happen with this drill, compared to a carbide tipped drill, by pushing it tip first into a normal carbide grinding wheel. Their drill formed a groove in the wheel, the carbide tipped drill had its tip ground back. Has anyone come across them before? Dave You often see them demonstrated at Ideal Home exhibitions and Tool Fairs etc. - where they invariably show them drilling through hardened steel files, etc. I've got a set and they *do* work - and will go through most materials. They're quite useful in situations when you're not quite sure what you're going to encounter - like drilling above windows when you don't know whether the lintel is concrete or steel. But I wouldn't regard them as precision devices, and normally prefer the correct drill for the material - wood bit for wood, HSS for steel, SDS for concrete, etc. -- Cheers, Roger ______ Email address maintained for newsgroup use only, and not regularly monitored.. Messages sent to it may not be read for several weeks. PLEASE REPLY TO NEWSGROUP! |
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Dave
wibbled on Sunday 20 December 2009 17:20 I have just watched a prog on digital tv (Ideal world) and they were demonstrating a drill set that can drill through wood, plaster, brick, concrete, tiles, mild steel, cast iron and bricks. See www.idealworld.tv They were saying that they were a tipped drill and the tip was cryogenically frozen cobalt. Now I have been around drills all my working life and I can't understand how a drill can keep an edge on these materials. They did demonstrate what would happen with this drill, compared to a carbide tipped drill, by pushing it tip first into a normal carbide grinding wheel. Their drill formed a groove in the wheel, the carbide tipped drill had its tip ground back. Has anyone come across them before? Dave http://www.screwfix.com/prods/95958 -- Tim Watts This space intentionally left blank... |
Drill all drills
In article ,
Dave writes: I have just watched a prog on digital tv (Ideal world) and they were demonstrating a drill set that can drill through wood, plaster, brick, concrete, tiles, mild steel, cast iron and bricks. See www.idealworld.tv They were saying that they were a tipped drill and the tip was cryogenically frozen cobalt. What does cryogenically frozen mean when it freezes at 1495°C? Dunked in water, perhaps? -- Andrew Gabriel [email address is not usable -- followup in the newsgroup] |
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On 20 Dec, 19:09, Tim W wrote:
Dave Has anyone come across them before? Cobalt-unobtainium alloy drill bits have been around for decades, but are a very niche market. Locksmithing is one user of them, for drilling hardplate in safes. Certainly the chap demonstrating drilling through files was at the model engineer exhibition 30 years ago. They're less useful than you'd think. Just how often do you need to drill something that won't respond to a carbide masonry bit, or decent HSS ? I've used mine a few times (every couple of years), but always for demolishing stuff, not for fabrication. As always when drilling out broken drill stubs etc., wandering sideways into the softer metal is a huge problem. http://www.screwfix.com/prods/95958 Those aren't. The usual "cobalt" drills these days have a "cobalt" (sic) coating on them, giving a bluish rainbow look. They're cheap, Chinese, and made of a secret alloy of rubber and bananas. No earthly use for anything. |
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Andy Dingley
wibbled on Sunday 20 December 2009 23:52 http://www.screwfix.com/prods/95958 Those aren't. The usual "cobalt" drills these days have a "cobalt" (sic) coating on them, giving a bluish rainbow look. They're cheap, Chinese, and made of a secret alloy of rubber and bananas. No earthly use for anything. Yeah - I was thinking more about the claimed ability to drill various substrates. The Bosch drills do work, (limited depending on substrate, very well on others). If I were the OP I'd buy the Bosch which has some record of usability before a random TV ad set. Cheers Tim -- Tim Watts This space intentionally left blank... |
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Tim W wrote:
Yeah - I was thinking more about the claimed ability to drill various substrates. The Bosch drills do work, (limited depending on substrate, very well on others). In desperation I tried these Bosch ones from screwfix to drill out a broken drill bit is a feed auger, it made no progress and then the tip disintegrated. AJH |
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We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Jon Fairbairn saying something like: If you solidify metal quickly enough you can get metallic glass. (My metallurgy supervisor was working on this thirty years ago by dipping a thermally massive rotating wheel into molten metal, resulting in a ribbon of metallic glass whizzing off. I've no idea of the current state of the art.) Dropping hot cobalt into liquid nitrogen might do it, but whether cobalt glass is any use for anything, I can't say. Reminds me of dropping molten lead into a bucket of water. Weird spikey shapes. |
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Grimly Curmudgeon wrote:
We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Jon Fairbairn saying something like: If you solidify metal quickly enough you can get metallic glass. (My metallurgy supervisor was working on this thirty years ago by dipping a thermally massive rotating wheel into molten metal, resulting in a ribbon of metallic glass whizzing off. I've no idea of the current state of the art.) Dropping hot cobalt into liquid nitrogen might do it, but whether cobalt glass is any use for anything, I can't say. Reminds me of dropping molten lead into a bucket of water. Weird spikey shapes. I thought that was how they made perfectly round musket balls? -- Dave - The Medway Handyman www.medwayhandyman.co.uk |
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The Medway Handyman wrote:
Reminds me of dropping molten lead into a bucket of water. Weird spikey shapes. I thought that was how they made perfectly round musket balls? They would form and solidify during the long drop in air. AJH |
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In message , andrew
writes The Medway Handyman wrote: Reminds me of dropping molten lead into a bucket of water. Weird spikey shapes. I thought that was how they made perfectly round musket balls? They would form and solidify during the long drop in air. I've wondered about that in the past - surely they would be a bit "pear" shaped from their passage through air -- geoff |
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andrew wrote:
Tim W wrote: Yeah - I was thinking more about the claimed ability to drill various substrates. The Bosch drills do work, (limited depending on substrate, very well on others). In desperation I tried these Bosch ones from screwfix to drill out a broken drill bit is a feed auger, it made no progress and then the tip disintegrated. Yes, I use them everyday. They are useful for being abe to drill through wood and masonry at the same time. They are pretty dire at wood and metal alone, taking twice as long as a normal drill, as they have a masonry style tip, so do not cut through the material, but rather just wear it away. On masonry, they are good. Alan. -- To reply by e-mail, change the ' + ' to 'plus'. |
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In article , geoff
writes In message , andrew writes They would form and solidify during the long drop in air. I've wondered about that in the past - surely they would be a bit "pear" shaped from their passage through air http://en.wikipedia.org/wiki/Shot_tower gives a good insight but I see what you mean about the pear shape, surface tension makes them round though (apparently). -- fred BBC3, ITV2/3/4, channels going to the DOGs |
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geoff wrote:
In message , andrew writes The Medway Handyman wrote: Reminds me of dropping molten lead into a bucket of water. Weird spikey shapes. I thought that was how they made perfectly round musket balls? They would form and solidify during the long drop in air. I've wondered about that in the past - surely they would be a bit "pear" shaped from their passage through air Quick Google suggests they were also moulded. Thinking about logistics, they would have needed to mass produce them. Wellington had 67,000 troops at waterloo, assuming they had 60 rounds each, thats around 4 million balls minimum. It must have been a huge scale industrial production. -- Dave - The Medway Handyman www.medwayhandyman.co.uk |
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"andrew" wrote in message ... Tim W wrote: Yeah - I was thinking more about the claimed ability to drill various substrates. The Bosch drills do work, (limited depending on substrate, very well on others). In desperation I tried these Bosch ones from screwfix to drill out a broken drill bit is a feed auger, it made no progress and then the tip disintegrated. The Bosch are great for drilling through tiles and into masonry or wood beneath. |
Drill all drills
In article ,
Doctor Drivel wrote: The Bosch are great for drilling through tiles and into masonry or wood beneath. They are utterly useless on hard porcelain tiles. -- *Sticks and stones may break my bones but whips and chains excite me* Dave Plowman London SW To e-mail, change noise into sound. |
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On 22 Dec, 01:46, geoff wrote:
I've wondered about that in the past - surely they would be a bit "pear" shaped from their passage through air No, you need an alloy with good surface tension, and a low viscosity fluid to fall through. This is why round shot is made by dropping through air until it's solid, rather than pouring directly into water. "Pear" or "teardrop" shapes might be an efficient shape for streamlining (i.e. lower drag for a shape that's already that shape), which also implies it's the lowest energy shape and thus the shape a drop is encouraged to form into by the viscous drag. However at Reynold's numbers this low, there's not enough drag force (relative to surface tension) to force a drop into any shape, so surface tension predominates. |
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On 22 Dec, 09:51, "The Medway Handyman"
wrote: Quick Google suggests they were also moulded. Swaged (nit-pickingly more specific than "moulding"). Not in the small sizes though. Dropped shot is cheap & simple. |
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Dave Plowman (News) wrote:
In article , Doctor Drivel wrote: The Bosch are great for drilling through tiles and into masonry or wood beneath. They are utterly useless on hard porcelain tiles. This is true BTDTGTTS. They are however brilliant on normal tiles. You can apply pressure (drill off) until you hear a 'crunch' noise and the sharp point penetrates the glaze, then carry on. No slipping at all. -- Dave - The Medway Handyman www.medwayhandyman.co.uk |
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In article ,
The Medway Handyman wrote: Dave Plowman (News) wrote: In article , Doctor Drivel wrote: The Bosch are great for drilling through tiles and into masonry or wood beneath. They are utterly useless on hard porcelain tiles. This is true BTDTGTTS. They are however brilliant on normal tiles. You can apply pressure (drill off) until you hear a 'crunch' noise and the sharp point penetrates the glaze, then carry on. No slipping at all. You can use HSS drills on normal tiles too. Make a center by using a tile scribe - or even a center punch used with care. And a slow drill speed with steady pressure. I'm not too keen on those multi-purpose drills as they do nothing well. But realise they can be handy if carrying everything with you. -- *Dance like nobody's watching. Dave Plowman London SW To e-mail, change noise into sound. |
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fred wrote:
In article , geoff writes In message , andrew writes They would form and solidify during the long drop in air. I've wondered about that in the past - surely they would be a bit "pear" shaped from their passage through air http://en.wikipedia.org/wiki/Shot_tower gives a good insight but I see what you mean about the pear shape, surface tension makes them round though (apparently). Thanks for posting that Fred, interesting read. I'd been looking around but didn't realise they were called shot towers. -- Dave - The Medway Handyman www.medwayhandyman.co.uk |
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Dave Plowman (News) wrote:
In article , The Medway Handyman wrote: Dave Plowman (News) wrote: In article , Doctor Drivel wrote: The Bosch are great for drilling through tiles and into masonry or wood beneath. They are utterly useless on hard porcelain tiles. This is true BTDTGTTS. They are however brilliant on normal tiles. You can apply pressure (drill off) until you hear a 'crunch' noise and the sharp point penetrates the glaze, then carry on. No slipping at all. You can use HSS drills on normal tiles too. Make a center by using a tile scribe - or even a center punch used with care. And a slow drill speed with steady pressure. I'm not too keen on those multi-purpose drills as they do nothing well. But realise they can be handy if carrying everything with you. I'm pretty much sold on them for that reason. Going back down 4 flights of stairs to get another drill bit is a PITA! TMH's first law of stairs; the more flights up you are, the more often you need to go back to the van. -- Dave - The Medway Handyman www.medwayhandyman.co.uk |
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Andy Dingley wrote:
On 20 Dec, 19:09, Tim W wrote: Dave Has anyone come across them before? Cobalt-unobtainium alloy drill bits have been around for decades, but are a very niche market. Locksmithing is one user of them, for drilling hardplate in safes. Certainly the chap demonstrating drilling through files was at the model engineer exhibition 30 years ago. They're less useful than you'd think. Just how often do you need to drill something that won't respond to a carbide masonry bit, or decent HSS ? I've used mine a few times (every couple of years), but always for demolishing stuff, not for fabrication. As always when drilling out broken drill stubs etc., wandering sideways into the softer metal is a huge problem. One way round that, is to obtain some high carbon steel bushes with the right size hole in the middle and a bush holder to clamp to the job, even it it means drilling another hole to attach it. The closer the drill bit is to the clamp, the better. It helps to prevent any circular rotation of the bush holder. Dave |
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Tim W wrote:
Andy Dingley wibbled on Sunday 20 December 2009 23:52 http://www.screwfix.com/prods/95958 Those aren't. The usual "cobalt" drills these days have a "cobalt" (sic) coating on them, giving a bluish rainbow look. They're cheap, Chinese, and made of a secret alloy of rubber and bananas. No earthly use for anything. Yeah - I was thinking more about the claimed ability to drill various substrates. The Bosch drills do work, (limited depending on substrate, very well on others). If I were the OP I'd buy the Bosch which has some record of usability before a random TV ad set. I had no intention of buying them thanks :-) I was just curious to know a bit more about them. Dave |
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Andrew Gabriel wrote:
In article , Dave writes: I have just watched a prog on digital tv (Ideal world) and they were demonstrating a drill set that can drill through wood, plaster, brick, concrete, tiles, mild steel, cast iron and bricks. See www.idealworld.tv They were saying that they were a tipped drill and the tip was cryogenically frozen cobalt. What does cryogenically frozen mean when it freezes at 1495°C? Dunked in water, perhaps? That was one point I could not understand. I always thought that liquid nitrogen was the coldest, easily available thing to use. Dave |
Drill all drills
On Tuesday, December 22, 2009 at 1:46:44 AM UTC, geoff wrote:
In message , andrew writes The Medway Handyman wrote: Reminds me of dropping molten lead into a bucket of water. Weird spikey shapes. I thought that was how they made perfectly round musket balls? They would form and solidify during the long drop in air. I've wondered about that in the past - surely they would be a bit "pear" shaped from their passage through air -- geoff I have seen moulds to make musket balls. Two halves in a pair of "tongs". Looked like they were intended for use on the (battle?) field after you'd raided the local church roof. |
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In article , harry wrote:
On Tuesday, December 22, 2009 at 1:46:44 AM UTC, geoff wrote: In message , andrew writes The Medway Handyman wrote: Reminds me of dropping molten lead into a bucket of water. Weird spikey shapes. I thought that was how they made perfectly round musket balls? They would form and solidify during the long drop in air. I've wondered about that in the past - surely they would be a bit "pear" shaped from their passage through air I have seen moulds to make musket balls. Two halves in a pair of "tongs". Looked like they were intended for use on the (battle?) field after you'd raided the local church roof. I think the "long drop in air" method is for smaller shot than musket balls: http://en.wikipedia.org/wiki/Shot_tower |
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