Hi Tony!
I agree with everything that Kurt said in his post on the Mustard Monster set-up; the parallel with the Jet 1642 is quite clear. You will really enjoy this lathe.
I'll make a few additional suggestions about the Jet 1642 set up I did for mine a few years ago (I got one very shortly after they first came out).
1. Checking the ways for sharp edges, etc. - I went over the bed casting of the ways to be sure that all edges created by milling the ways flat were "eased" - simply by slightly chamfering them with a fine mill file, and then following this up with some further clean-up and smoothing with wet-dry carbide abrasive. This ensures that as you handle the bed and go about attaching it to the legs, putting on the headstock, etc. you won't encounter an edge that could cut you, and of course will be OK to work with for the life of the lathe. Check both outer AND inner long surfaces on both parts of the ways, as well as the ends. Slight chamfers (ca. 1/16") won't effect the function, and will make the tool more user-friendly.
2. Clean up and seal mating surfaces of ways and legs - After removing the cosmolene, etc. from the mating surfaces of the lathe bed and the corresponding surfaces of the tops of the leg castings, I also made sure there were no projecting surfaces, rough edges, threading "spur", etc. before bringing the pieces together to screw them together. After thoroughly cleaning the mating surfaces with mineral spirits and buffing with some fine steel wool, I then applied a very liberal coat of Bostik "Top Cote" (you could also use Boeshield T-9 or other similar product) to seal the cast iron before you screw the parts together. It doesn't hurt to seal the metal, and can help avoid rusting of the machined surfaces and 'possible rust-fusing' of the parts together through time.
3. Ease edges of headstock, banjo, and tailstock - Before installing them on the ways of the new lathe, I also went over and eased the 'bottom' edges of all machined surfaces of the headstock, banjo, and tailstock by chamfering the edges anywhere the machined surfaces of these sliding parts are supposed to glide along the ways. By removing any sharp edges, and smoothing/polishing them before installing these parts, you improve the chances that they will glide effortlessly and will not "bind" as they are moved, due to sharp edges digging-into the surface of the ways. You should only have to do this once while setting-up the tool. I also do occasional periodic clean-up of these "bottom" surfaces, usually twice or three times a year on the tailstock and banjo. To do this, I use a fine grit rubberized abrasive block (obtainable from Klingspor), also known as a "rust eraser".
4. Check tightness of pulley set screws on motor and spindle - A quick check of these before getting it up and running might eliminate the "clicks in the headstock" that are sometimes reported for the 1642. At this time you should also insure that the sheaves are aligned properly, and the belt is in the correct position.
These suggestions may seem like minor "tweaking" that could slow down your set-up a bit, and increase the 'time to first shaving', however doing them at the time of first getting the tool in working condition can enhance the performance of this lathe (or any lathe) for the life of the tool. The manufacturers generally don't have time to do these minor but useful 'tweakings' on most lathes, but by doing them in advance of taking it "on your first spin", it can prove to increase your enjoyment of your investment every time you turn it on and put a tool on a rest!
Congratulations on the new machine!
Rob Wallace
(.... who is awaiting the arrival of his new Jet 1220, and who will do all of these suggestions yet again when this lathe arrives....lathe #3 is supposed to get here on Tuesday)