Is it my turn? Anything to do with lathes, mills and other shop tools

When I worked at the cannery, we had a little 110v "suitcase" Miller TIG unit. Handier than a pocket on a shirt. We'd get a call that something was broke on the packing line, I'd get my stuff together, wait for the packers to go on break, haul ass out there, plug it in, weld it up, and be back in the office drinking coffee before their 15 minute break was over.

Wish I could have glommed onto that when the cannery closed.
 
So went at the tailstock alignment again today. Kinda think this is a legitimate way to do it. Both dead centers were spun to check for true. Pulled the tailstock apart and carefully stoned any high rough spots on the mating surfaces.polished greased the locking cams Anyone comment if centered point to point eyeball with a magnifying glass is good? got good alignment both side to side and up down with the quill at both ends of the travel.
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Still fighting tight focus on the camera.
 
I'm not an expert - but that seems a reasonable way to do it Gary - although, the proof of the pudding being in the eating...suggests that turning a parallel diameter and measuring the taper might even be better...

I'll bet that 2M, JimD54, TimeMachine and FredinToon would have better ideas. TM, Jim and Fred are professional machinists and 2M is a whiz-bang innovator in the shop...
 
So went at the tailstock alignment again today.
Since 2M is throwing out tricks....
Gary, put that piece of paper between the centers and slowly push till they touch. If they're dead nuts on, paper won't move. Any misalignment will bend the paper.
 
Since 2M is throwing out tricks....
Gary, put that piece of paper between the centers and slowly push till they touch. If they're dead nuts on, paper won't move. Any misalignment will bend the paper.

See - (as Goober Pile would have said)..."ahhhh tole ya so....."
 
sure no problem I'll take the 3 jaw off again... o_O :shootme: :smoke:

Not thrilled with the backlash on the cross feed, adjusted it as good as I could get it,but that's pretty much the norm on the G4003.
 
Did a little more sleuthing and think'n
Set a laser ruler on the ways, left, right, center,
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pointed at garage door 22' away. marked the laser path on the garage door in 2 widely separated spots. Repeated a couple times with identical results. It revealed a bit of twist in the bed. The left rear (right facing the lath) was low. Lathe has remained bolted to the stand it came on. Loosened the bolts on that end, bingo!
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Laser paths now much closer, will shim between lathe and stand bolt down and recheck til the lines all match.
 
Some backlash is inevitable, and is one of the things to take into account when machining. Years ago, I spent a bit of time reworking my Atlas crossfeed parts to get my backlash of 0.009"-0.010" down to 0.002"-0.003". Any less and I would experience binding. It's now back up to 0.004"-0.005".

So, when doing diameter reducing out->in cuts, run the compound inward to a good stopping point to get its threads pre-staged to handle the pressing forces.

Opposite when doing boring in->out cuts, prestage the compound by turning its screw backwards.

And, all crossfeed readings are done with its leadscrew loaded in the cutward direction.

Aligning the spindle and tailstock's centers' points is a quick and easy way to align the tailstock, and is just fine for most general-purpose work. But, for precision machining on shafts, your earlier dual-diameters comparison is the preferred way.

I have a straight/polished 1/2" x 12" SS steel bar that I've centerdrilled true, and use it as a gauging bar between centers. Mounted, I simply run my toolpost mounted dialgauge up/down the rod to determine tailstock centering, and to setup offsets for tapers...
 
Yes, Ratranger the new machines are impressive. And also can be more troublesome with all the complexeties (alarms) that come with them.
The most hands on fun I've had with cnc lathes were with simpler , more personable machines, like old Okumas and DaeWoo's with things like door safety switches bypassed. Times have changed . These old tool box trophys were all made on single spindle , single turret lathes with live tooling.
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gggGary I'd ofcourse set the tool height first by facing to the center for a check. Get it just a few thou under center. For taper after that use the tail stock adjustment to eliminate the taper. Tool height is critical as to reduce cutting pressure that influences a straight linear cut test.
 
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