My Grandfather was an upholsterer and he'd taught my Dad bits of the trade. Anyway, the hammer I got handed down was my Dad's. It has a head 5 5/8" long with a sweet arc to it (when viewed from the side). The one end is solid and 1/2" in diameter at the striking surface. The other is "split" but comes back together at the striking surface. That surface is 5/16" diameter. This is the magnetized side.
The claw on this hammer is attached (screwed to) the heel of the handle.
I'm not sure about the "holding tacks" part but Dad told me that when Grandpa was at Delker Bros. (Henderson, KY) he held his tacks in his mouth. As fast as one came out it was tacked and there was another ready for the next ride. I don't think Grandpa would be able to compete with pneumatics but he put in a full day.
Besides the day job at Delker, Grandpa had a shop in the stable behind the house and took on side jobs. When Dad was a kid he'd help with dismantling furniture and tearing off old fabric. Grandpa taught Dad how to scrape an old finish off using freshly snapped glass shards. Once I asked if Uncle Bobby ever helped in the shop. Dad's reply was, "Yeah, just long enough to find the change (coins) that slipped down inside the chairs and couches."
sigh...
UA100, missing his Dad and reminiscing like an old guy...