Darn, lathe down for maint.

[Buckshot]

...............I have some issue in the threading gearbox, but luckily no broken gears. I had to take the carriage off to remove the leadescrew and QC box so I thought I might as well take it apart and check it out too.

Everything was very good except the wormgear that supplies power to the apron for long feed up and down the bed and power cross feed.

http://www.fototime.com/363D3F5CEE75601/standard.jpg

The leadscrew goes though the wormgear. The wormgear has an internal key which rides in the keyslot of the leadescrew. So when the leadescrew is turning, the wormgear turns, and so turns another gear in the apron of the carriage. The wormgear rides in steel bushing caps (At extreme rt and lft) ) at either end, and these are carried in ears off the back of the apron.

Both the bearing caps and the bearing surfaces of the gear were scarred and worn. I turned down the surfaces of the wormgear and then bored out the bearing caps. I then turned and bored 2 sleeves for a press fit on the worm gear and a nice running fit in the caps. Logan still supports the lathe and has these parts new. The gear is $267 and the bearing caps are $34 ea. Not really too bad considering, but I didn't want to have to pay it if I didn't have to! I used red Threadlocker on the sleeves when I pressed them on the wormgear.

Luckily Glen, one of the Burrito Shooters also has an 11" Logan so I was able to use his lathe to fix my lathe! Of course working at someone else's place makes for a longer repair time because you don't know where anything is.

I was going to turn bronze bushings for the wormgear to run on but this would have cut down even further on the available thrust surface bearing against the inside shoulders of the end caps. These had been worn also. The thrust is considerable when cutting, as it has to move the entire carriage along the bed but also withstand the cutting effort, so I left them steel on steel.

http://www.fototime.com/0CF5A5E9AD5C3C1/standard.jpg

The bed looks a bit naked with the carriage off. You can see the leadescrew and QC box are still there.

http://www.fototime.com/38BEA1F7AAF07C4/standard.jpg

The pile of parts to go back on as soon as I get the QC box sorted out. This is almost like having your kid in the hospital :-)

The problem was probably simple lack of maintainence. The apron is 'wet' meaning it's supposed to have oil in it. When I bought it I asked the guy if it was supposed to have oil in it. Clever person that I am, I saw the pipe plug in the bottom and the word 'Oil' stamped next to a bolt. His remark was, "Yeah oil is supposed to go in there, but it all leaks out."

Actually it does, but it kind of slowly OOOOOooozes out to the tune of maybe an ounce a week. With spindle oil at $14/gallon it can ooze so far as I'm concerned.

....................Buckshot

[dragonrider]

I am confuse as to why you removed the carriage, could you not have removed the lead screw support on the right side of the bed and simply slid the lead screw to the right in order to remove it from the gearbox????

[Buckshot]

I am confuse as to why you removed the carriage, could you not have removed the lead screw support on the right side of the bed and simply slid the lead screw to the right in order to remove it from the gearbox????

............Nope. The leadscrew goes into the QC box and has a keyed drive gear and a nut holding it on from the inside. Would be nice the other way though. Found the problem in the QC box today. The countershaft carrying all the gears bent. Back up to to the friend's house. Good thing he has a milling machine as I need a 1/8" keyslot half the length of the shaft.

..............Buckshot

[Buckshot]

..............Between work and having to mail order a couple parts, and running back and forth to my buddy's house to use his lathe to fix MY lathe, I got it all done. I hope to get it put back together by this evening!

http://www.fototime.com/9FFF49E8FCD44A1/standard.jpg

Here's the wormgear with the new sleeves pressed and epoxied in place. One bearing cup on.

http://www.fototime.com/6BAA7B3FA3B208C/standard.jpg

And installed back in the apron. I decided to make some oiling changes just because they'd make me feel better :-). I'm an oilaholic and if a little will do a little good, then a lot is much better, right? They way they oiled before was the gear that the worm turned dipped into oil in the apron. This would then find it's way down to the bearing caps. The wormgear generally didn't turn too fast and since it lasted 25 years I guess it was okay.

The hole marked with the "A" is for an oil tube. The one marked "B" is one I drilled through the bearing trunnions and the bearing caps. The holes marked "A" intersect the other hole. A set of holes in either trunnion.

http://www.fototime.com/B8FE8259451C0E3/standard.jpg

I went to Pep Boys and bought some 3/16" brake line for the oil tubes. The holes were drilled .185" and the brake line is .1875" so it was a nice press fit. The holes which were marked "B" had been tapped for 8-32 set screws which sealed them off and bear against the tube ends. I doubt that that is necessary except to seal them, as I can't see the pipes going anyplace.

The lines clear the halfnuts and bottom gibb and go around the apron to a terminal block on the right side.

http://www.fototime.com/0CA97D4C7DAFB08/standard.jpg

I used a piece of half inch keystock for the block and soldered the tube in place. I milled the ends down to form ears which were drilled through and then the apron was drilled and tapped to match. I drilled through the block 3/16" in 2 places, then counterbored .246" to accept a couple Gitts ball oilers. In this photo they haven't been installed yet.

The QC box and lead screw has been installed and I just have these couple of heavy cast iron things to hump back up in place. The QC box just humms quitely now so I should be good to go. It's been very traumatic having my baby in the hospital these past few weeks :-) ! My shop looks like a train wreak.

..................Buckshot

[dragonrider]

Glad to hear you got it going, it really sucks when your toys are broke. I am going to have to take down my Bridgeport soon for some needed work in the head. I lost the back gear a few months ago. It's a varidrive head and I have another belt drive head that I will just swap into place while I fix the varidrive.

[9.3X62AL]

It will be good to have Buckshot back to his previous care-free self again, now that his lathe is on the mend. For the past few weeks at the Burrito Shoot, he's looked like somebody just shot his dog with a pellet gun 10 minutes ago. In his garage the other day, he kinda hovered near the machine like an ICU RN with a critical care patient. I had hoped to have a few more weeks of Buckshot Divided Attention, with which to engineer a victory in the Burrito Shoot. Alas, it is not to be.

[grumpy one]

Buckshot, those oil tubes may be a bit tricky, or they may just work, it seems a bit hard to predict. My milling machine addressed a similar problem a bit differently. The bevel gears that raise and lower the table are up underneath, and they get oiled with way oil by using a small diameter nylon tube connected by pressure fittings on both ends, with a grease nipple so the oil can be injected under pressure. Like on a Bridgeport, all of the grease nipples on the machine have to be lubed with way oil, and where grease is actually required, there are no grease nipples. It's part of a British plot to keep us all on our toes.

The point of all that is you might care to check before you finally assemble, by putting some oil in the top of the tubes and seeing whether it makes it to the bottom, and whether it leaks excessively at the bottom. If it does all is not lost, you can still put pressure fittings on the ends of the tubes - but if you wait until after you've put the lathe back together, it might be a bit more difficult.

Geoff

[Buckshot]

...............Yeah Al, right :-) (How could he tell?)

............Paul, after our room addition is completed I'm going to be getting a mill. Probably close to December next year or maybe a bit earlier. I'm looking at a 9x42 import with a 2 axis DRO and power table. My lathe is a variable speed and it's nice, but I think I'll probably go with a step pully on the mill.

...........Geoff, Those oil tubes work fine. My main concern was to keep them out of the way. I checked them before mounting the apron and again after getting the carriage all together. After it was installed I ran the carriage round trip on the bed. Everything seems to be working just fine I'm glad to say!

In the next couple months I need to put new bearings in the vari-speed countershaft. I can get the bearings beforehand and have it out and back in the same day, unless I find something needing repair. I shouldn't as it still runs smooth other then an annoying bearing click.

................Buckshot

[drinks]

My antique Atlas has oil cups and oil holes with snap caps all over the machine.
When I got my 7x12" China buffet special a few years ago, I could not find any oil holes, so I eventually made 4 oil holes, with a counterbore top and installed 2, 1/16" vinyl tubes to oil sites that require removing part of the shields, otherwise, to access them.
I suppose that oversight was in the interests of promoting sales of parts and machines.

[Linstrum]

Hi, Buckshot, glad to hear you got your baby up and running again. I was kind of surprised about the wear and bent shaft, those problems seem a little odd for a machine like that. The lube tubes you installed sound like a good way to keep the wear from happening again. How on earth did the shaft get bent?

I know exactly how vulnerable you feel when a machine that is part of who you are is down for repairs, sort of like losing your left hand for awhile. It has been a year since I set up my new lathe. Last week it was down for a day when I did maintenance and a tune-up that I hope will help to keep it accurate and long-lived. I had noticed that it was starting to cut a slight taper and when a lathe starts to do that it is definitely time for a tune-up! I readjusted the headstock on the ways and got it back to plus or minus 0.0002” on a six inch cut on a 1.25" bar of AISI 1018 hot rolled steel, which is about as good as can be held in a lathe under the circumstances. While it was apart I felt a little lost, but I have a back-up lathe of sorts to make repair parts. If I ever need to machine something when the lathe is down I can do simple outside turning on short pieces in the milling machine by chucking up the part to be turned in the quill and holding the tool bit in the table vise. The tool bit is fed with the table feed and the cut is made by running the knee up and down. The work that I have done that way is surprisingly accurate. When you get our milling machine, keep that in the back of your mind as your “reserve lathe”.

I am still working on making the false headstock to spread the wear out over the whole length of the ways so the first three inches in front of the chuck don’t get worn out like on my first lathe. When I get it finished I’ll take some photos.

There is a season, turn, turn, turn - - -

[9.3X62AL]

Among my few real talents is a knack for foretelling the future, it seems. During today's Burrito Shoot, the Owner Of The Rebuilt Lathe out-pointed me shooting wheelguns at 25 yards. Whupped me at my own game.

[Buckshot]

.................Drinks, I was thinking of getting one of those little 7x12's as it'd be handy to do stuff where you might have to tear down a setup on the other lathe. A few times of that would about make it worthwhile! Besides, they're just so cute :-)

............Linstrum, hey dude! You must still be in California if you're close to your mo-sheen. The shaft I bent was in the QC box. I think I got the gear on the left change lever across 2 of'em. Their diameters down the shaft are very similar, being as they reduce only by 2 teeth at a time. However I made a new shaft so that didn't cost anything.

I don't know how it happened but I busted a tooth off a 60 tooth change gear too. However that may not have happened at the same time. The stud it rides was loose on the banjo and may have gotten cocked and bound up and then the tooth broke? Dunno but it was broken.

What cost was buying all the bushings I replaced in the QC box (as long as I was in there) that gear, and then I also bought a 32 tooth change gear. The 32 tooth can replace a 24 tooth and then I have a hole nuther bunch of threads I can cut in between the others in the QC box, like 27 TPI fer-instance. That happens to be the TPI for Krag and 1903 action screws. It also adds some of the extra fine threads too. It just about doubles the theads.

I'm not concerned with those heathenish, communistic, bastardized meteric threads. If I need'em I'll just cut something close and use a bigger wrench to make'em work :-)! Besides you have to have another thread chasing dial and they're so screwed up the dial has to have 4 gears of it's own.

...............Buckshot

[dragonrider]

"heathenish, communistic, bastardized meteric threads"

My sentiments exactly.

[floodgate]

Rick:

".................Drinks, I was thinking of getting one of those little 7x12's as it'd be handy to do stuff where you might have to tear down a setup on the other lathe. A few times of that would about make it worthwhile! Besides, they're just so cute."

Take a look at MicroMark <www.micromark.com>. They are offering one of those little lathes, upgraded to 7" x 14", with inch dials, and a DRO available, currently on sale. Looks like the best version to get. They also make a nice, matching mill, with a tilting column (sounds weird, makes sense for certain applications). A very good outfit to deal with for those into model machining.

Doug