Hello, I am looking for info on these taps. Tapered over their length, coarse thread? , . Instead of a square shank at the top, they are rectangular.

Hi Lou, I think they were called blacksmiths taps. Maybe boilermakers tap? I found one a few years ago. Wish I could remember what I did with it.

Mike

Hello, Mike. Thanks for the info, I will follow up on that!!

Hello, Mike. Looks like blacksmith's Taps to me. Thanks again, Lou

Are they all 12 TPI.?

If so maybe earlier versions of these boiler mud plug taps?

Hello, humber2. Thanks for the reply! Mike nailed it, they are Blacksmith's Taper Taps!!