As mentioned a few days ago, today I took delivery of a Thor dead blow nylon hammer.
I did some research as there are several weights.
I started with the standard Thor spec. These are the ones with a copper surface on one side and a coiled leather surface on the other.
#1 size is 710gm
#2 size is 1070gm
#3 size is 1600gm
I have all three and #3 is really at the useable limit for swinging. For me anyway!
The dead blows come in the following sizes, with two replaceable nylon surfaces.
#1010 is 525gm (1lb)
#1212 is 700gm (1.75lb)
#1414 is 900gm (2lb)
#1616 is 1250gm (2.75lb)
#2020 is 2250gm (4.25lb)
There may well be a #1818 but I didn't come across this size.
I have gone for the #1616 because it falls between the weights of the standard #2 & #3. I think I got this right. It's big but manageable. The biggest size would have been too unwieldy. Keith at BHM uses one, but his is smaller than #1616.
At the same time I bought a replacement coiled leather refill for my Thor #2 which is "well used". It took some persuasion to get the old one out, and the new one had to be pressed in like a kingpin bush. It's a tight fit, eased with a smear of Vaseline. (Another use).
I'll post some pictures when I get chance.