what is this for

[Dagny]

dont say tapered hole. It's been around here a long time

 

[wingnut_1]

An old pipe tap (NPT) possibly...

 

[APEowner]

Actually you drill the hole straight and it cuts tapered threads. It's a pipe thread tap.

 

[Dagny]

It cant be way to much pitch look at it again.

 

[zkling]

I don't think it's a pipe tap, TPI? Diameter range?

 

[DocsMachine]

Probably an old Irontite tap. It's used for cast-iron crack repair.

Doc.

 

[WWIIjeep]

Not a pipe tap.

Not an Irontite tap either.

It's an old blacksmith's taper tap.

 

[Dagny]

thanks jeep I googled some more used on boilers and wagon wheels the internet is amazing.

 

[Matthew3901]

could it be a swage for squaring a round hole in metal?