Strange drill bit

>>>
>>> I found this bit at the dump. It has a tapered shank & is marked "star
>>> - hammer - twist". It has a chisel point, not a cutting lip, so it
>>> clearly does impact cutting & hence (?) is for masonry. But it is not
>>> carbide tipped! It has some rust, so it can't be solid carbide, can it?
>>>
>>> So, I guess the question is: is there some steel alloy that is used for
>>> masonry impact drilling?
>>>
>>> Thanks,
>>> Bob

>> It's steel, not carbide.
>>
>> The tapered shank of that bit fit into a hexagonal or octagonal
>> holder, maybe 6" long. The holder had a slot cut in it which allowed
>> you to use a wedge to remove the bit - just as in removing a Morse
>> taper bit. The holder was hit by a hammer, and rotated between hits.
>> The advantage of this over a regular star drill was that you could
>> have a big, solid shank on a small diameter bit. The bits were
>> sometimes spiral, sometimes straight.
>>
>> By the way, common star drills ain't so common anymore. I needed to
>> hang a couple of shelves in the basement the other day. Figured 5/16"
>> screws would be fine, so I grabbed a box of machine screw caulking
>> anchors I'd had for years. Hmmm - full box. Hole size 5/8". Looked
>> for a 5/8" star drill. Plenty of 1/4", 3/8", 1/2", 3/4", 1" and
>> larger, but no 5/8". No problem, I'll just pick one up at the
>> hardware store. The third try - the biggest hardware store in
>> Portland, Maine, serves mostly commercial customers - actually had
>> three sizes. None of the sales people had any idea what a star drill
>> was, even in the store that had them. No 5/8", of course. So I ended
>> up using 3/8" screws, which need 3/4" holes. Now I knew why the one
>> box was full, and the other almost empty....
>>
>> John Martin

>
>
> My "ground rod driver" is an elderly Black and Decker hammer "drill"
> No rotary motion at all, but simply bangbangbang. It came with a full
> compliment of star drills and holders as well as the holders that you
> grab and turn.
>
> Works as good as a rivet gun for driving ground rods
>
> $10 at an estate sale. In the factory metal box with all the
> accessories
>
>
> Gunner
>
> Political Correctness is a doctrine fostered by a delusional,
> illogical liberal minority, and rabidly promoted by an
> unscrupulous mainstream media, which holds forth the
> proposition that it is entirely possible to pick up a turd by the clean end.