Anyone know the iron foundry which used this mark?
Randy, It sure looks like the Fairmont Tool logo. They were the supplier of all tool rolls at this time for Pierce, Karl
https://tsdrsec.uspto.gov/ts/cd/casedoc/sn60567302/ORC20060310183501/1/webcontent?scale=1
Maybe they supplied castings as well?
Randy, looks like they started using the logo in 1923 but waited until the forty’s to trademark it for themselves. The on-line info does not mention a foundry, but who knows. Only the Pierce script hammer has the logo on the reverse side of the head. Karl