Amuse Ourselves For A Moment - What If

Bamban

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You could order a purpose built gunsmithing lathe with configuration of your choosing, how would it be like? For me here are the things that are a must

Very short spindle with just 2 speed spindle control
Highest rated spindle bearings with the least spindle run out
Belt drive, using link belt system
Inverter Drive, at least 3 HP motor
Side gear cover notched to accommodate outboard spider without swinging the cover out.
Enclosed gear change box
2 inch spindle bore
9 inch bed way for rigidity
T slotted cross slide
40 inch length center to center
Splash lubricated apron with sight glass
Target minimum net weight not less the 2000 pounds
DRO factory installed
At least 5 inch TS quill travel
Cast iron stand, heavy
Spindle center height from bottom of cabinet to be not greater than 40 inches, ergonomically correct for my height
 
Looks like a good list to me....

How much of that is in the new PM1440GT...
 
Purpose built? Okay...
Very short spindle with just 2 speed spindle control
What does this do for me? Short spindle? With a big enough bore, why would i care? 2 speed? why only 2?
Highest rated spindle bearings with the least spindle run outt
Highest what? Tribology is a complex subject. Highest load? Longest wear? Smoothness?
The least runout, yes. Good idea.
Belt drive, using link belt system
Inverter Drive, at least 3 HP motor
Why belt drive? Why not hydraulic drive? Why link belt? Why not silicon belt? Why any belt at all? Why not chevron gears?
3hp is a good place to be. After all, especially for gunsmithing, no one gains much by taking a 1/4" cut on anything. So 5 or 10 ponies would be excessive, IMO. 3hp would give good startup/braking power for the hefty spindle and head we'd want.
Side gear cover notched to accommodate outboard spider without swinging the cover out.
Enclosed gear change box
Yes and yes.
2 inch spindle bore
9 inch bed way for rigidity
T slotted cross slide
40 inch length center to center
Maybe a teensy bit more bore. 2.125 bore. That way a 2" bar fits easily or something that *should* be 2" but actually is a bit over (like always) fits easily.
9inch bed minimum. Purpose built? I could go for more rigidity just cuz.
T slots in the cross, but only if it comes with all the tooling to support that ;-)
Might go 49" centers. Goose gun barrels can be what? 38"? Plus a 9" action? So 47" would allow solidly barreled actions, like bolt guns, to be held between centers -- which a guy would never need, ever, or at least until the day he got this machine installed, then these jobs would appear from nowhere.
Splash lubricated apron with sight glass
Target minimum net weight not less the 2000 pounds
DRO factory installed
At least 5 inch TS quill travel
Cast iron stand, heavy
Spindle center height from bottom of cabinet to be not greater than 40 inches, ergonomically correct for my height
Yes, yes, yes, yes, and yes.
I might add:
at least 6 leveling feet.
foot brake
certainly a taper setup

If you like 40" height, then build it to 41". Why? Because you'll wanna be standing on a 1" rubber mat because you'll be spending a LOT of time at a sweet machine like this ;-)


Wrat
 
What's with the old dinosaur crap? I want a composite/granite bed and a direct drive spindle thank you, with individually driven/infinitely variable feed and electronic threading capability.

Or I just call Matt at QMT and order a RML-1640V with constant speed control and call it good. :D
 
What's with the old dinosaur crap? I want a composite/granite bed and a direct drive spindle thank you
What does that kind of bed gain? I mean other than sounding new, what material properties does it possess that's inherently advantageous to machinetool construction above and beyond cast iron or forged steel?
Just curious.
Direct drive spindle i could understand wanting though i'm not sure how that's done. A >2" hole through your armature is unlike any motor my limited experience has observed.

Wrat
 
A hole through a armature is easy, though a motor like that would not be cheap. Didn't even get into the uber precise and noise immune power supplys to drive this stuff. I mean is we're going to dream here, why not hold millions of an inch?

There are much better materials available than cast iron for dampening vibrations, rigidity, and thermal stability. Cast iron is just cheap, easy to manipulate, and was readily available during the Iron Age. :)
 
A hole through a armature is easy, though a motor like that would not be cheap. Didn't even get into the uber precise and noise immune power supplys to drive this stuff. I mean is we're going to dream here, why not hold millions of an inch?
Of COURSE a hole in an armature is easy. I'm just saying i've not seen one and certainly not one of that kind of size. By the time all your windings were in place for 3 ponies, that would be a big head on that lathe. Are you saying you know of such a motor?

And this, to me, wasn't really a 'dream' thing, so maybe i oughta start there. Instead of farming this out to George Jetson, to me it was more of a spec thing. Using available -- maybe not OTS, but available -- technologies to build up a purpose-built machine. Emphasis on 'built' as in something buildable.

"Gunsmith Lathe" is as overused as eBay sellers saying "mint". It seems to mean about nothing, except, perhaps, a shorter bed for the size of bore you get. If that. So such an academic exercise is not without merit, IMO. What would people that genuinely work on guns (as opposed to salesmen and spectators) really want in a lathe if they could get it?

There are much better materials available than cast iron for dampening vibrations, rigidity, and thermal stability. Cast iron is just cheap, easy to manipulate, and was readily available during the Iron Age. :)
Well, okay, is that what you're saying? You brought it up. I'm not saying no such material exists (though cast iron has its place) but I am asking just what properties are being claimed, here? Cast iron we know. But before we throw it out like so much "dinosaur crap" i was just wondering what we're gaining. that's all.

Wrat.
 
And this, to me, wasn't really a 'dream' thing, so maybe i oughta start there. Instead of farming this out to George Jetson, to me it was more of a spec thing.

Wrat.

Sorry, misread/misunderstood the original post.
 
Out of curiosity, i revisited this thread. Came across this remark.


Or I just call Matt at QMT and order a RML-1640V with constant speed control and call it good. :D
Not really being up on my contemporary hardware, I checked this out.

WOW! What a sweet looking machine. Believe I'd be fully content with such a device in the right setup and accessories. Didn't know about this line.

This game is over for me. I'm gonna hafta just set on the bench, now.

Wrat

p.s. anyone know what kinda moolah we're talking about, here? he annoyingly keeps his prices to himself.
 
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