I got another email this morning from Kozo that has photos of Shin’ichiro’s tools for machining small hex head screws. I have been thinking about square head bolts now I see how to make the tooling. Here are the photos and descriptions to make screws using 1.5mm hex stock.
The tool for machining outside diameter of the screw.
The rear view of the tool with the work-holding-bearing detached.
The rear view of the tool with the work-holding-bearing installed. The work will be supported with a bushing having a hole which is close running fit over the work.
The tool for parting off the screw.
The rear view of the parting tool.
Close up of the parting tool with the tool bit retracted.
Close up of the parting tool with the tool bit advanced to cut-off position.
The parting tool and the outside-diameter-machining tool, both installed on the turret head. The turret head also was made by Shin’ichiro himself.
The outside diameter of screw is being machined. (1)
The outside diameter of screw is being machined. (2)
The screw is being parted off.(1)
The screw is being parted off.(2)
The screw is being parted off.(3)
The thread is being cut with a screw cutting die. The work is being revolved with a homemade socket wrench.
The hexagonal head is being chamfered with a conical cutter.
The machined small hex-head screws.
"The key-point for designing the tools is to keep “shortest stress-path” to machine such a small work with high accuracy. If it were long, the work could not even be machined due to its flexibility.
I hope you will enjoy these photos.
Kozo"
Many thanks to Shin’ichiro for showing his methods for making the very tiny hex head screws, and thanks to Kozo for bridging the communication gap.
Dan