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Lathe Purchase--Have Requirements Now

Starting a new thread since I have more specifics. Boss told me we will be ordering a second lathe this month. We are still deciding which one.

Requirements:

1. Will be used for chambering barrels at a higher volume than I can do on the PM 1440GT

2. Will be a manual lathe. A CNC lathe will be added as a third lathe some time in the future

3. Need to be able to change between SAE and Metric threads without swapping gears inside the lathe

4. Want variable speed
 
PM TL16 series does inch/metric "without any changes"

Does "Variable speed" mean "VFD" ? Or gear changes to change speed
 
PM TL16 series does inch/metric "without any changes"

Does "Variable speed" mean "VFD" ? Or gear changes to change speed

Variable speed mean the lathes comes with speed pot built in. I added one to my PM1340GT at home through a VFD, but would like to have that feature built in.
 
Not sure I understand...you want higher volume that what you can do on the 1440, but still want manual. Sounds like the same boat to me. CNC for everything including sending reamer in for high volume. Even machines that are capable of automated threading like a hardinge type machines won't be adding much volume.
 
Id be looking for higher quality rather than higher volume like a good standard modern or rkl leblond. To get a 2” bore its going to be big
 
Not sure I understand...you want higher volume that what you can do on the 1440, but still want manual. Sounds like the same boat to me. CNC for everything including sending reamer in for high volume. Even machines that are capable of automated threading like a hardinge type machines won't be adding much volume.

With some updates to how we are chambering barrels, and a second lathe we will quadruple our output.
 
I think you may be boxing yourself into a corner for a sometime job. Big machines are just plane slower to use on small work. Barrels for actions like a Rem 700 dont need a big machine.

The specs on the Arca electronic threading lathe show a 1.25" hole through spindle. Earlier this week I chambered a 1.35" shank barrel, and tomorrow and I doing a 1.25" shank barrel. Most of the barrels we do are 1.25" diameter shanks.

If it had 1 9/16" spindle it might be a good fit. I can always do the big stuff in the 1440 GT.

We also have two competing ideas. If I were making the call it would be a tricked out 13x40 or 14x40, or even possibly a CNC machine. However, there is a big push for a 17" manual lathe because that is what a couple machinists/manufacturers have and like.

I don't like big machines because of all the bushings needed and the general hassle of chambering. I really like my inboard and outboard spiders and short headstock. However. these bigger lathe guys can go from blank to chambered barrel twice as fast as I can, and their end product specs out as good as mine. So I don't have as good of case to make as they do.

To be honest, I don't think it's in the dial in where they beat me. I can get most barrels dialed in to under .0002 at the throat around .0002 at the breech in 10 minutes or less with the Interapid long reach.

Where I am slow is how I double check everything and make multiple light passes.

I take .050" for the first 2-3 passes on the tenon, and I like my last past to be within .010". That minimizes deflection and keeps the diameter consistent. When threading I use the compound only. I make .005" cuts until .030, then .003 to .048, the .002 or .001 after that. I clean the chips off after each pass.

When chambering, with a flush, I go in .100 at a time at first then .050, pulling the reamer back so the flush clears the chips. I do that to about .300 to go, then I pull the flush, patch out the oil, and scope the bore to make sure everything looks okay. Then I hook everything back up and go to within .020 to 030", pull the flush, patch out the bore and scope again. I then measure with a feeler gauge between the shoulder and action and add .002 (.002 for a sandwiched lug), zero the tailstock, and make my final cut.

These other guys chamber in one shot. I am sure they make bigger cuts in both turnings and threading, and don't check their measurements as much as I do.
 
Automated turning/threading cycles. Might even be a way to set up to ream the chamber as well...
All servo controlled with the "feel" of a manual machine (supposedly...)

 
The specs on the Arca electronic threading lathe show a 1.25" hole through spindle. Earlier this week I chambered a 1.35" shank barrel, and tomorrow and I doing a 1.25" shank barrel. Most of the barrels we do are 1.25" diameter shanks.

If it had 1 9/16" spindle it might be a good fit. I can always do the big stuff in the 1440 GT.

We also have two competing ideas. If I were making the call it would be a tricked out 13x40 or 14x40, or even possibly a CNC machine. However, there is a big push for a 17" manual lathe because that is what a couple machinists/manufacturers have and like.

I don't like big machines because of all the bushings needed and the general hassle of chambering. I really like my inboard and outboard spiders and short headstock. However. these bigger lathe guys can go from blank to chambered barrel twice as fast as I can, and their end product specs out as good as mine. So I don't have as good of case to make as they do.

To be honest, I don't think it's in the dial in where they beat me. I can get most barrels dialed in to under .0002 at the throat around .0002 at the breech in 10 minutes or less with the Interapid long reach.

Where I am slow is how I double check everything and make multiple light passes.

I take .050" for the first 2-3 passes on the tenon, and I like my last past to be within .010". That minimizes deflection and keeps the diameter consistent. When threading I use the compound only. I make .005" cuts until .030, then .003 to .048, the .002 or .001 after that. I clean the chips off after each pass.

When chambering, with a flush, I go in .100 at a time at first then .050, pulling the reamer back so the flush clears the chips. I do that to about .300 to go, then I pull the flush, patch out the oil, and scope the bore to make sure everything looks okay. Then I hook everything back up and go to within .020 to 030", pull the flush, patch out the bore and scope again. I then measure with a feeler gauge between the shoulder and action and add .002 (.002 for a sandwiched lug), zero the tailstock, and make my final cut.

These other guys chamber in one shot. I am sure they make bigger cuts in both turnings and threading, and don't check their measurements as much as I do.
Your only delays are threading (the electronic threading on the acra will let you thread at a higher rpm) and your double checking your work. With a flush you can go in all at once- no need to stop and patch out just to take a peek. Use a reamer stop and set it about .025 short, one shot reaming, measure once and dial it in. If you cant talk somebody out of a 1.350 barrel just do it on the other lathe. Most barrels i do are 1.200- i can go way bigger but nobody really cares between a 1.2 or a 1.250. Imagine threading at 1000+ rpm and taking deeper cuts like .025 on the first pass? Imagine reaming a whole ultramag chamber without stopping because you have confidence in your setup? Thats where youll be soon.
 

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