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Hercus 9" A, extra gears in steps of 5T
- Thread starter Dave022
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- Jun 7, 2013
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Threading, I assume. Does it have a chart showing change gears for threading and feeding? Is it a change gear or quick change machine?
Its quick change. The manual doesn't specify the use of any gears with these teeth in any threading chart. I know that there are 127/100 or 60/63 transposing for metric. I also know that there is a 54 gear with the South Bend 9" which I don't have
- Joined
- Jun 7, 2013
- Messages
- 10,086
There are special change gears for quick change lathes for cutting pitches that are not on the chart, although those do not look likely candidates.
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- Feb 2, 2013
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when i had my hercus arh, it also had a qcgb.
i had a spare 20T gear, but you would normally use the 40T for most feeds or threading
there were threads and feeds displayed on the qcgb legend for both 20T and 40T gears
i suspect, the extra gears were not stock to your machine- but it sure opens a world of possibilities
so many feeds, so many threads that can be cut
calculating gear ratios will get interesting for all the change gears and the qcgb
i had a spare 20T gear, but you would normally use the 40T for most feeds or threading
there were threads and feeds displayed on the qcgb legend for both 20T and 40T gears
i suspect, the extra gears were not stock to your machine- but it sure opens a world of possibilities
so many feeds, so many threads that can be cut
calculating gear ratios will get interesting for all the change gears and the qcgb
Here's an excel spreadsheet I put together for my Jet 1024 lathe when I needed to cut a thread pitch that wasn't on the factory tables. It is a live spreadsheet, so if you update the gears and the QCGB ratios for your Lathe, you will be able to see what threads your extra gears can cut.