Years ago I bought a pair of Imperial and metric thread identifiers for small nuts and screws (for example see https://www.amazon.com/Innovative-Co...thread+checker ). The set of thread identifiers are very handy. The checkers are strung on steel cables and this keeps the sets organized but the cable makes it difficult to check threaded parts that can’t be removed. After seeing Marv’s Thread Checking board (see http://www.homemadetools.net/forum/t...4317#post63615 ), I wanted to organize my sets the same way. The caddies are made from ¾” red oak. I applied several coats of clear polyurethane from a spray can to seal the wood and protect it from oil. Below are photos of the Imperial thread version.
I also added a pair of missing UNF 6-40 and 8-36 thread checkers machined from 12L14 steel to complete the Imperial set for the typical UNC and UNF threads from #6 to ½”. I have the taps for these sizes but had to resort to single point chasing the external threads and verifying dimensions using the three wire method. The sets are not too expensive and I recommend buying rather than making unless you really want to improve your external threading technique and three wire measurement skills. I used a conventional single thread chasing technique to make these small thread parts.
However, I have started using the upside down threading tool in the QCTP and lathe in reverse threading technique demonstrated by Joe Pieczynski on his You Tube channel (Published on Jun 9, 2016) and highly recommend this technique.
Thank you for looking,