Threading question

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3strucking

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IMG_0526.JPG IMG_0513.JPG this is my first lathe and I have a question on threading. Can someone help me understand the chart. I know I have it geared for imperial with the 54-60-90 gears. I understand the settings until you get to the last two columns on the right of the chart.
 
Hi rightway,
welcome to turning!
the legends can be a bit confusing, maybe i can help out a bit.

the last 2 columns are for (upper half of the chart) imperial threading and (lower half of the chart) crossfeed rates
the roman numeral II, signifies feed selector knob is set to II
the last column signifies gear placement and number of teeth, to achieve the feeds.
the transposing gears on the headstock may be need swapped to attain different feed rates on the chart. many threads can be cut from the same set of transposing gears when the selector switches are utilized.
the selector on the lower left changes the ratios in the gearbox, that setting directly affects the leadscrew speed.
I is fine thread, II is slightly coarse thread, III is the coarsest threading available( and some half thread pitches- not used a lot but handy nonetheless)

the selector lever on the lower right is the cross feed/leadscrew selector- it switches between leadscrew operation and crossfeed shaft operations (crossfeed ratios are relatively high- for fine feeds)
 
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So if I want to cut 24 tpi I would set dial to Roman numeral 1 and turn dial to 6 correct?
 
If I swap gears to a 60-30-54-90 combination and set dial to II it would cut 4,5,6,7,8 tpi? based on what number 1-9 i had the dial set at?
 
thanks for the info. It is great to have people willing to help out those who are new .
 
it's my pleasure to have helped out.
we all started as newbs
 
just to be sure I always take a scratch cut on the of my part ( after bluing it ) and lay a thread pitch gauge on it to make sure its what I want. bill
 
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