Few Pictures Of The New Pm 1440 Gt

[sanddan]

Congratulations!

Bet you're on pins and needles with the wait.

 

[wrmiller]

Are all those with 1340gt's looking to upgrade?

Not me, I have more lathe than I really 'need' now. And I have a tray under my gearbox so there's no oil mess for me to clean up.

 

[Bob Korves]

That gearbox arrangement looks pretty good to me.

Not too often will you be changing messy gears between the spindle and gearbox. Could someone explain to a metric lathe guy what the diagram in the top left of the change chart indicates where it has a 120 & 127 middle gears. Is this because the lathe has a metric leadscrew or is it for cutting threads on an imperial leadscrew?

Are all those with 1340gt's looking to upgrade?

The 127 tooth gear is just being used as an idler. It reverses the direction and takes up space in that setup, nothing else. Actually, that lathe uses four different gear box drive gear changes to make the inch threading range. My Kent USA only uses two to do the same thing. That lathe, and mine, is missing 27 tpi, a common pipe fitting thread. There are ways around it...

 

[Sendit]

I'm assuming these are exterior gear changes like you commonly see.

 

[MonkMan]

Thanks and Congratulations! Great photographs!

 

[jbolt]

The 127 tooth gear is just being used as an idler. It reverses the direction and takes up space in that setup, nothing else. Actually, that lathe uses four different gear box drive gear changes to make the inch threading range. My Kent USA only uses two to do the same thing. That lathe, and mine, is missing 27 tpi, a common pipe fitting thread. There are ways around it...

I has an inch pitch lead screw. Per the thread chart the 127T gear is used on the inch threads and the 120T gear is used on the metric threads.

 

[rwm]

Why would they make the green switch turn on a faucet? Seems like the water would be bad for the electrical stuff...
R

 

[Bob Korves]

I has an inch pitch lead screw. Per the thread chart the 127T gear is used on the inch threads and the 120T gear is used on the metric threads.

Jut to be clear... Metric threads on the inch lead screw requires both the 100 and 127 gears, which work together to transpose the ratio. Note that there are 25.4 mm (exactly) in an inch and that 127 is half of 254. The 100/127 gear is called a transposing gear. In the case of inch threads, it is only acting as an idler gear on this lathe. In the case of metric threads it is acting as a ratio changer on this lathe.

 

[jbolt]

Jut to be clear... Metric threads on the inch lead screw requires both the 100 and 127 gears, which work together to transpose the ratio. Note that there are 25.4 mm (exactly) in an inch and that 127 is half of 254. The 100/127 gear is called a transposing gear. In the case of inch threads, it is only acting as an idler gear on this lathe. In the case of metric threads it is acting as a ratio changer on this lathe.

Understood on the inch to metric transposition, poorly worded on my part.

Maybe I'm splitting hairs here but in regards to the inch only threads the 127T gear does affect the ratio between first and last gear so it does have a use other than "just taking up space" with the caveat that if there were no metric thread capability it could be a completely different arrangement.

 

[Bob Korves]

Understood on the inch to metric transposition, poorly worded on my part.

Maybe I'm splitting hairs here but in regards to the inch only threads the 127T gear does affect the ratio between first and last gear so it does have a use other than "just taking up space" with the caveat that if there were no metric thread capability it could be a completely different arrangement.

Idler gears do not affect the ratio at all, only the gears at the ends of the gear train do that. Any number of teeth on the idler gear will give the same result, just changes the gear spacing and the idler gear rpm. In the case of this lathe, the single idler gear, regardless of tooth count but 127 teeth in this case, only serves to reverse direction and take up space. In the case of driving the 127 tooth gear and then using the 100 tooth gear to drive something else, that is compound gearing, and must be considered in separate equations.