Indeed I was aware of the large set (8 or 9 gears, I don't remember); there's a fellow on ebay selling sets for around 260$
but this 2 gear trick looks like it does most of the common pitches- good enough for me anyhow until I acquire gear-cutting capability and can make the whole set myself
As Robert said above easy to make the change to metric threading. I just made this change on my craftsman 12x36. I got my gears off Ebay. Less than $50 including the shipping. There are several threads on this on the forum. I had previously uploaded the craftsman manual on the qchb. It includes a chart listing the change gears for I believe every tpi that can be cut on a craftsman 10 or 12 lathe with a qcgb. To convert a metric thread to imperial divide 25.4 by the metric thread. For example an upcoming project is going to require me to cut 1.8mm threads. 25.4/1.8=14.11 tpi. There is a listing in the manual for 14.11 tpi. The manual is attached.
A better copy of that manual plus the installation and parts manuals on the 1500 and 6800 Atlas QCGB's is already in Downloads. I uploaded it about three years ago.
I bought the two gears from Clausing some time ago, JIC I ever needed to do a metric thread (I never have cut a metric thread but stranger things have happened). Prices weren't much more than for used gears on eBay. One nice thing about the 30 Second method is that it uses the never used by most people 4.0 to 7.5 TPI thread range.