This is nothing new, just my version for 3 different size chucks.
These adapters will allow you to hold a bolt head within the lathe chuck.
Note that the bolt head is not gripped by the jaws at all but instead
the round shaft of the bolt or part is what the jaw will clamp to.
Not just bolt heads but a lot of parts that have a dimension that will not
allow the part to fit securely in the chuck jaws. These adapters will allow that.
I made mine out of 12L14 steel but aluminum or brass would work .
Brass or aluminum would make them "soft" jaws.
All 6 corners can be used for different diameter screws or stock
that you are working with. To use them just fix one on each jaw with the set screw.
Close the chuck so that all jaws touch in the center. Next just drill out the center
with a drill bit that will accommodate your part. I like to keep this diameter just
a bit under the bolt or shaft diameter.
You can see one example of a 4-40 allen cap screw being turned into a Dog Point.
A second example is a 1/2-20 bolt with a flattened end for another project.
There are a lot of holes that need to be tapped. The last picture shows the tapping stand
I used to tap them. Here is the link to the tap stand build.
Tapping Stand or Hand Tapper
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