Unusual drills

[bollie7]

G'day All
Whilst helping my fiance clean out her late fathers shed I came across these oddities (to me anyway)

Exhibit A
A brass drill. As in a drill bit made from brass or a brass alloy. It looks like a normal HSS drill except that its made from brass. It doesn't have a shank and someone has drilled a smaller dia hole into the shank end of it. If it had a shank originaly it has been turned off in a lathe, not cut off with a saw. Its about 13mm dia (probably 1/2") Someone has made a pretty poor attempt to sharpen it with a grinder. I spoke to our Metallurgy teacher at work and he reckons it would be pretty much useless for drilling anything except very soft wood. Maybe it was made as a promotional item (desk top toy/paperweight ?) by a drill manufacturer.

Exhibit B
A 3 flute taper core drill or reamer perhaps. Has a reverse helix on it. The way the lands are ground it would be turned the same direction as a normal drill. There is about a 2.5mm difference in dia between the point and the shank. (as best as I could measure it with dial calipers, considering its got three flutes) Shank dia about 11mm. No markings at all on it.

Ok, over to you blokes to come up with explanations. Maybe the truth is out there after all. :)

bollie7

[swk]

Bollie,
brass tools are/have been used in dangerous environments like gunpowder/fireworks factories. I imagine they are also still used in hazardous areas in more modern contexts like refineries/paint factories etc. They are "non sparking".

Regards
SWK

[Bryan]

Could the tapered one be a reamer for tapered pin holes? Though it doesn't really look that reamer-ish to me.

[jhovel]

That 2nd pic looks a lot like a taper pin reamer I have. I puzzled over it a bit then tried it on my modified Douglas shaper drive. I works quite well, but because it expells the chips downwards, you have to push on it to make it cut. On the other hand, it doesn't jam because it doesn't pull in. When you stop pushing, it just lifts itself out.
Feels odd but works well in a battery drill running slowly.
Joe

[Chief Tiff]

Bollie,
brass tools are/have been used in dangerous environments like gunpowder/fireworks factories.

They are also used were magnetism must be avoided. We used to carry bronze tools on minesweepers; you will never come across a more useless tool than a bronze Philips screwdriver.

I still have a bronze cold chisel in my shed; it tends to blunt fairly quickly but is magnificent for carving through stubborn blocks of cheese....:rolleyes:

[4-6-4]

Greetings Chaps I was confronted by a copper chisel in my early days whilst working in the hold of a Shell Tanker. The Vic Railways also used Tapered machine reamers on bolt holes where they wanted a very tight fit. Yours 4-6-4

[azzrock]

They are also used were magnetism must be avoided. We used to carry bronze tools on minesweepers; you will never come across a more useless tool than a bronze Philips screwdriver.

I still have a bronze cold chisel in my shed; it tends to blunt fairly quickly but is magnificent for carving through stubborn blocks of cheese....:rolleyes:

id heard that hand tools were anesthetic stainless on mine sweepers but hadnt thought of cutting tools. how about a bronse hack saw blade. makes me wonder how magnetic
tungsten is.
aaron

[Ueee]

id heard that hand tools were anesthetic stainless on mine sweepers but hadnt thought of cutting tools. how about a bronse hack saw blade. makes me wonder how magnetic
tungsten is.
aaron

I smashed a parting tool tip today:doh:....when i backed the tool out what was left of the tip fell out of the blade and i lost it. Late, whilst cleaning up the lathe with a magnetic wand, one grey chip just wouldn't get picked up. I realized after a while it was what was left of the carbide tip, so i'd say (at least the grade the tip is) carbide is not magnetic. But what do you braze it onto? A carbide tipped stainless hacksaw blade?:rolleyes:

[azzrock]

exactly makes you wonder. cheif tiff can you deguaze a hack saw

[Chief Tiff]

Hmmm..... although the handle can easily be manufactured from a non-mag material such as an ally/zinc alloy the frame would still need to be steel. A stainless frame would be "min-mag"; but I think the blade would have to remain HSS (or high carbon if carbide tipped).

As for degaussing; no passive method would work so you would need to wrap degaussing coils around the saw. As this would probably reduce the usefulness of the tool I suspect that the only way would be to wrap degaussing coils around the whole work area with a magnetic monitor high up in the shed roof. The active system would cope ok providing the saw never cuts more than about 20 degrees from it's initial calibrated setting.

However, I live <20km from the coast so until someone develops both a magnetic seeking aerial dropped bomb and a genuine need to use it on me, I would say that this post is merely an exercise; a way of needlessly destroying some brain cells and assisting the onset of either arthritus or carpel tunnel syndrome :D:D:D

[azzrock]

great answer. a first class baffle them with bull ship

[GSRocket]

Bollie...since you come from Abermain, there's a good chance they used the brass drill in the underground pits.