- Joined
- Dec 21, 2018
- Messages
- 48
I made the 91C style Tap wrench 3 years ago, and started the 91B size shortly after. I FINALLY got around to finishing the smaller size.
Both are made from hardened A2 tool steel and are pretty much exact copies of the Starrett models. The only thing I did differently was added a hole on the opposite side of the slot in the end. This way if anything happens and disassembly is required, the retaining pin can be pressed out through the hole.
I turned them manually on the lathe, and roughed out the flat part on the mill. I brought them to work to do the flared profile on the flat part and the pocket for the tap on the CNC mill. I made a custom slug and used a keyway broach to eliminate the radius in the pocket for the tap and get a square corner. I also heat treated them in the oven at work. The large one warped a little, but it's not noticable when using it.
I had material on hand for the smaller one, and I think I paid about $60 for material for the larger one. I had a lot of fun making them, and they were a fraction of the cost of buying real Starrett ones.
Sent from my Pixel 2 using Tapatalk
Both are made from hardened A2 tool steel and are pretty much exact copies of the Starrett models. The only thing I did differently was added a hole on the opposite side of the slot in the end. This way if anything happens and disassembly is required, the retaining pin can be pressed out through the hole.
I turned them manually on the lathe, and roughed out the flat part on the mill. I brought them to work to do the flared profile on the flat part and the pocket for the tap on the CNC mill. I made a custom slug and used a keyway broach to eliminate the radius in the pocket for the tap and get a square corner. I also heat treated them in the oven at work. The large one warped a little, but it's not noticable when using it.
I had material on hand for the smaller one, and I think I paid about $60 for material for the larger one. I had a lot of fun making them, and they were a fraction of the cost of buying real Starrett ones.
Sent from my Pixel 2 using Tapatalk