What kind of reamers are these?

[tmenyc]

A bunch of these old chucking reamers found their way to me, No. 8 and 10, all with this tear drop base. I can't find them anywhere. The imprint says "Drill USA No.8". Curious!

Thanks,
Tim

 

[FLguy]

Would you use a fine lapping compound on these to get the hole to a high tolerance and fine finish ??

 

[savarin]

Are they worn tapers?

 

[Ulma Doctor]

they are the old, hand made kind of reamer you are not likely to see many of.

 

[Superburban]

They look like giant versions of the old push drill bits.

 

[Cadillac]

If I had a guess it would be a straight drill with a worn out mt1 shank?

 

[tmenyc]

Don't think so: I have probably 20 of them, mostly 8 and 10, all with the same shank, from different sources that have found me. They wouldn't all be worn the same way, I wouldn't think.

Tim

 

[Illinoyance]

A taper shank masonry drills with the carbide worn off.

 

[cbellanca]

Look like single flute wood bits.

 

[AGCB97]

I have a bunch of those also and if I remember right they are masonry bits that fit some type of percussion driver