Is Government Liquidation contractually required to be brain dead?

Russ, if you do not mind me asking, what did that rebuild of yours involve? Definitely not in the next 10 years, but one day I would like to find and maybe rebuild a very fine lathe like this.

i
Reply to
Ignoramus12893
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Quite a bit, actually. I bought the lathe without running it but with the expectation that if I couldn't get it working I could always flog the tooling on eBay for the purchase price, there was quite a bit of tooling and one bit would have covered the price in it's entirety.

On arrival the controls on the lathe were rusted, and the drive was not completely working. I started dealing with the rust by removing things and cleaning, most of the rust was in the zero setting dials and such and interfered with the tenths clearance. The taper vernier dial took most of a week to get apart - one hour at a time in solvent in the ultrasonic bath, but once it got open .002" the rust was able to come out and it was cleaned and back together in an hour or so. It was the worst, really.

The drive was a lot more work. The tubes (this is an all-tube drive) was OK, a couple of marginal signal tubes were replaced. I found a couple of caps that were marginal, repaired those. I had the motor armature turned and new bearings and brushes put in, they managed to mess up the series field (this is a compound wind motor with series and shunt fields) and that caused some fun until I stood over them with the motor on the test drive - it would arc like crazy after the field crossover point. Once that was fixed I had to replace on of the special rheostats in the speed control, they each vary only on half of the turn but on opposite halves and someone had put in a standard linear taper pot. That was fun as the drive was increasing the armature voltage the filed was decreasing. Anyway, that was about 3-4 months, and a niggling problem I caused during this time took a couple of months to track down (a whisker of the wire on the pot was touching the lead primer paint inside the pot housing, and was draining off *just enough* of the gate that I couldn't get the field all the way down...) but since fixed has not given a lick of trouble.

During that time I was doing "weekend projects" - take something off, clean/repair, replace. After a while I had a lathe with all the functionality but a very worn bed - .007" in the front inverted V. I finally bit the bullet and broke the lathe down into components. The bed, saddle, cross slide and taper slide all went with me to Dallas for a grind, I had the bed top ground, the saddle had the cross slide dovetails ground and top cleaned up, the cross slide top was squared up and the taper slide had the inside ways parallel ground.

When I decided to strip the lathe I also decided that a stripped lathe was a lot easier to paint, so from this point on I was removing old paint and priming/painting as necessary. I ended up painting the base, bed, headstock, gearbox, saddle, apron and tailstock in that order, pretty much as things went back on.

Realigning the headstock was interesting. I had to scrape the headstock back into alignment while maintaining bearing on the ways. I was lucky to get it in as few cycles as I did, I built a spreader bar that helped lift the headstock on and off the bed as well to flip it over for scraping. I scraped the tailstock base in to the bed to use as an indicator holder to check the headstock alignment, made it level to the leveled bed at the same time. I think I stopped when the 1.375" test bar was .0004 low at 18" - if I remember right that was the droop.

The saddle was a lot more work. I had to set it the proper height above the leadscrew and feed rod so that the apron would have the proper alignment, this entailed removing some material from the V ways and replacing it with a castable resin called Moglice. The minimum thickness of the resin is .032 thus the V way cleanup - it also removed most of the oil and such and put some tooth for the Moglice. The wear was considerable on the saddle, once I had the bottom the right height and the top level I used feelers to figure out the cuts - on the leading edge I only needed to take off .012 to get the .032 I needed. In casting I placed a couple of layers of tape on the bed ways and cast the oil grooves in place. I also had to replace all the oil lines in the saddle as they were gone (I'd patched over some rust areas that leaked, but this was the time to finally replace with copper. The meter units had been replaced some time before when they were found to be clogged.

The apron needed a lot of work. The bushings for the feed rod were egged out where the rod passed through, so I had to bore them out and put in some bronze replacements, keying them in place. Most of the bearings had to be replaced as well as the arms for the oil pump and the cam on the longitudinal feed that worked the oil pump (the pump has 2 cams, on for cross feed and one for longitudinal), the worm gear on the feed was about gone and had to be replaced, the pinion on the rack needed replacement. The oil pump was rebuilt, not really needing it but as long as I was in there....

After the saddle was Mogliced and some oil pockets scraped, the apron and all the associated rods put back on, and the electric leadscrew reverse put back on in time. Lots of finagling there. Since I had set the cross slide square to the headstock when doing the Moglice all I had to do on the cross slide was to mill the bottom for some Multifil (a way material like Turcite). I glued that up using a surface plate as a master so it'd come in flat, and it needed very little scraping. I needed to do the bottom of the cross slide before calculating the verticals, and after getting it to the right height I was able to shim the gib in with a .002 shim, and I've put off the final fitting. Maybe this summer.

The compound was scraped back in, the base milled flat (.005" wear - from rotation, believe it or not) and scraped to the top of the cross slide. I've since replaced the compound assembly but have not yet refitted it.

The tailstock was low and I simply shimmed it .006" up. It was level from scraping the base earlier. I had to make a new nut (1/2-8 LH ACME, so I had to make the tap as well) earlier and made a couple of new quill assemblies as well, one in MT2 and the other in MT3. The eccentric on the tailstock clamp was shot and needed a new one which was made,and a replacement handle I had for the clamp fitted (someone had bought one for the lathe but never fit it). I think they're riding in new bushings now too.

The taper attachment needed new bearings all around (8 of them) and I rebuilt it to fit the new slide. I still need to mill off the sides of the part that slides in the body to clear off some pitting, I plan to attach some steel strips and to grind it all parallel. It's "ok" right now if I simply avoid the last 3" of travel near the headstock, and with better than 10" travel that's fairly easy.

Most all the gaskets were replaced in the process. Someone had used some black goop instead of gaskets, and this was a mess to cleanup, entailing some serious work in the bottom of the gearbox. All wipers and felts were replaced. In general all oil passages were cleaned and verified to be working.

In retrospect it might have been better to get a lathe in better shape, but really, a lot of this sort of thing would have to be done anyway sooner or later. What I did was far from a 'concourse' rebuild, ignoring the paint (well, it's not the best in the world, but it's 'serviceable' and looks pretty good from 10' away). I was mighty tired of stripper, bondo and toluene (I had to shoot a lot of paint in 45 degF) by the time I was done.

I did do some 'bling' stuff - the beat up plates for threading/feed and controls were replaced with new where it didn't cost much. I tapped the old drive screw holes and used screws in replacement. But generally if a part was serviceable I simply cleaned and reused it. Since finiahing the rebuild I've replaced the cross feed screw & nut and rebuilt the dial assembly, and replaced the screw in the tailstock, both feel a lot better now.

Before and afters are here:

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Reply to
Russ Kepler

That's a great way to buy stuff!

This is very impressive.

So, you paid someone to do it professionally, on professional equipment, right?

I never could imagine that resin could hold up in an application like this. Very interesting.

your story and pictures are very inspiring.

i
Reply to
Ignoramus12893

According to a coworker of mine, this is an outgrowth of policies set at the end of WWII where it was seen as the government's duty to throw perfectly good stuff away (vehicles driven off floating piers into the sea, planes flown directly from manufacturer to scrapyard) so as not to affect the market for new goods... --G. Lyford

Reply to
glyford

You realise that the real shame here is that it's going to stay there until the 3rd week of April...

Also, this Bridgeport:

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But I mean, really, why taunt us with this stuff NOW? "Hey, it's broken, but it might not be too bad. But you have to let it sit RIGHT THERE for another TWO MONTHS! Because we just want to MAKE SURE. Neener neener..."

--Glenn Lyford

Reply to
glyford

That actually makes sense, in a perverse way....

-jc-

Reply to
John Chase

Still hurts

Reply to
Brent Philion
[lathe bed grinding]

I don't see a way to get a flat parallel bed otherwise. A couple others had their lathe beds done at this shop (Commerce Grinding in Dallas) and checked them optically - they were flat straight to .0001 over the lenght of the bed. Can't as for more than that (well, you can, you just can't afford it).

And you need a good clean grind as the bed is being used as the master for the Moglice.

It's strictly in compression. In shear it'd snap, in compression it's quite strong after it sets up.

The nice thing is that using it let me get the saddle aligned to the headstock and leadscrew and level without pulling the saddle, scraping, cleaning, putting back on, etc. I had fixtures on the corners that used

10-32 bronze screws against the ways to hold it setup, a little Loctite on the screws and the saddle came off and went back on with very good return to position. Once I was happy I prepped the bed (really, really clean, tape for the oil grooves, release sprayed and polished) mixed up and gooped on the Moglice and pressed the saddle back on. It took some movement and hammering to get to back in place, I think I used too much Moglice.

I'd do it that way again.

Reply to
Russ Kepler

Yow! Well, it certainly makes me feel better about the rebuild I did on my Sheldon R15-6. Of course, nobody has bid on the Monarch, either!

Jon

Reply to
Jon Elson

I used Moglice on my Sheldon rebuild, and am very happy with the results. The pressure, in Lbs/sq in is very low on machine tool slides. This stuff, when set, is nearly as hard as aluminum, maybe. It does scrape several times faster than cast iron, but is still quite a solid material. My big worry was that I would not apply it right, and it would break up and not stay attached to the carriage. But, it has held up really well!

Jon

Reply to
Jon Elson

Well, it CAN be done, but it is complicated, and takes a long time, removing a little at a time. I started with a master precision level, but ended up getting a Taylor-Hobson Talyvel electronic level during the project. That thing is REALLY sensitive, displaying a tenth of an arc second. (I think that is .00005" per foot, roughly.)

I made a little test carriage that had two hand-scraped blocks that rode on the main ways. I could mount the Talyvel either along the bed or across it. I kept working until the Talyvel had a constant reading along the full six feet of the bed in both orientations. This pretty much proved out the ways as being straight to .0003" overall, and parallel to the same tolerance. Then, I did a little more scraping to improve surface contact, and finally lapped it with a bench stone to reduce the roughness. The "scraping" was done with a die grinder and Cratex cloth-bonded abrasive wheels, because the bed was as hard as tool steel!

I don't recommend this process as being cost-effective, but it proves that a large lathe bed CAN be redone by hand. But, you DO need some special tools.

Jon

Reply to
Jon Elson

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