I was following this thread and thought that the Russian guys setup was pretty clever and fast. Even though he will be replacing that forward-reverse switch on his lathe soon. Reading what smallblock said about the way to do it, I decided to give it a try. I found a piece of scrap tubing for my arbor and cut a slot with the band saw. using some 1/2 X 1/2 tube and a big nut, I fabricated the support piece and a simple wire guide. The tube fit in the tool holder so I could adjust it to center height. Figuring out the thread pitch and length is pretty easy in the threading wizard, but you cannot write the program with the wizard for several reasons. The main one is that the wizard uses the PID function of Mach 3 to set the spindle speed and this takes a few seconds to stabilize. What happens is the wire begins to wind up immediately while the rpm is stabilizing before the carriage moves, so you end up with a big knot of wound wire at one end of the spring. So I unchecked the PID, Spindle Speed Averaging and Use Spindle Speed in Synch mode boxes. This bypasses any spindle speed adjustment from Mach 3. Now the spindle will begin to turn at the rpm right away eliminating the knot of wire. HOWEVER- because Mach 3 is no longer counting pulses and adjusting the speed, the rpm will usually run too fast because of the voltage in the VFD ( 13.1) being higher than what Gecko asks for
( 10.0). On our machine, if you asked for 100 rpm, it would actually go up to about 125. So you need to do some experimenting with your rpm so you know how much to write in your program to get the correct rpm at the spindle. I found that if I asked for 80 rpm, the spindle would then run at 100. So, in the threading wizard I put in 100 rpm as the speed, .5 as the pitch and 5" total length. The calculator gave me the following info- the feed rate should be 50 inches per minute. I then wrote a simple program like this-
G91
G1Z-5 F50
M3 S80 ( remember 80 actually gives me 100 rpm)
G4 P1.5 ( pauses the carriage to be sure all the wire is wound on the end before retracting)
G0Z5
M5
That is the program you see in the video-
After a few trial and error runs, I found that 36" of wire gave me a nice 3 wire flat on each end and exactly 5" long and .5 between each coil. I didn't have any piano wire, so I just used some re-bar tie wire which is not very springy. I then adjusted the feed rate down to see if I could make a tighter coil, and it worked fine except I forgot that tighter coils require more wire, so my .25 pitch spring ended up being only 2.5" long. It only took about 15 minutes to cobble together the arbor and guide assembly, so if a guy needed some springs of a certain size, he could probably make them up in a few hours.
https://youtu.be/fgXaS_QyTio