"Finished" Low speed mod to Sieg C6B

Finally, it is is "finished" (I can now see improvements so I guess it never will be!). Originally, I was going to use timing belt and cutting the timing pulleys was a bit of a stumbling block, not having a dividing head or similar. Poly-V (multi-rib) belt made that problem go away.

This is the new bottom end pulley to drive the countershaft and increase the top end speed:

The ribs were cut using an appropriate tap "tailored" with a slitting disk and mounted in the toolpost.(same for the countershaft pulley)

This is the finished mod in "low gear":

This is the high speed direct drive config:

The countershaft pulley is 130mm x 20mm in cast iron, I think ally might have been a better choice, its quite a flywheel.

I cheated by buying a C6 "banjo" and counter shaft spindle from Ketan at Arcurotrade. The mod would have been cheaper if I'd fabricated the thing from barstock, but I can't weld (yet) and don't have the gear to braze that mass of steel.

The pulleys are home made.

The ratios available are roughly motor:spindle 8:1 and 1.7:1 instead of the original 2:1.

It still won't take quarter inch cuts at 50revs, but it does have real grunt now, so much so that I'm tempted to leave the drive belt a bit slack so I don't get into serious trouble, particularly when parting off.

This picture shows the CD I made with 60 holes around the edge to drive a rev counter:

Next step is the electronics, because I used 60 holes, I can use a bench frequency counter which will directly readout in rpm to set the lathe up, before implementing a dedicated rev counter and display. I'm using infrared TX/RX devices without modulation. They are completely enclosed so neither dirt nor interfering light should be a problem.

This is what the stupid questions have been about over the past months - thanks guys!

Steve