Making and Using Precision Reamers

Part 2: Materials and Fabrication

In Part 1 of this article I discussed the proper and safe use of these precision tools. This part will deal with how to make them. The materials used for these reamers can range from exotic to what some would consider scrap. Most commonly, they can be made from ordinary drill rod or from custom ground HSS reamer or drill blanks.

Drill Rod

The advantage to drill rod is it is cheap, readily available, and you probably have it on hand ready to use. Drill rod does have some drawbacks. You need to harden it before you use it as intended. Not hardening can result in minor bothers like having to sharpen it before every use, or major catastrophes where a key binds up under power and is ruined in the blink of an eye (although you may be too shocked to blink).

Drill rod is not a precision product. If your requirements are for accuracy on the order of 0.001” then it will probably be fine. Do not expect rod of the “same size” to actually be the same. In a recent order of 0.110” rod, I had sizes ranging from 0.1093” to 0.1108” in the 6 pieces. Only two of the pieces were the same (within 0.0001”) from end to end. This may not seem like a huge difference, but if you make a hinge rod for a saxophone from the largest piece of 0.110 and a “matching” reamer from the smallest of the batch, the results will not be to your liking.

Considering the drawbacks mentioned, with some patience and realistic expectations, reamers of high precision can certainly be made using drill rod. When length is needed, such as for reaming out stack posts on a tenor or bari sax, drill rod is the best choice in my book. The HSS tool blanks of that length are just cost prohibitive.

Did I mention that you need to harden reamers made out of drill rod? I am sure to mention it again. It is that important.