Help me make a D-reamer

Brad

Benevolent Overlord and site owner
Staff member
Learning what works is a good thing. Understanding and confidence make things go faster and come out better.
 

Gary

SE Kansas
I see how you got the shape in Picture #1; but how did you machine the reamer as shown in Picture #2? I assume a grinder and file.
 

Ian

Notorious member
Freehand with a file for the edge relief, and sectioned the cutting part freehand on a regular bench grinder.

First I relieved the back with the lathe and the tool set up eccentric, then filed the edge relief:
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Here you can see the sectioned part better. I ground the section down to exactly meet the edge that I had filed, with no over-run so that the profile of the tool as turned on the lathe remained intact. The side opposite the cutting edge was left alone so it would "back up" the cutting edge and keep the form true in a hole. After heat treating, I lightly dressed the relief angle and the flat with an Arkansas stone and put it to work.

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