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Trailblazer
11-29-2007, 11:22 PM
I am buying a 12x36 Taiwanese lathe. I tried to remove the chuck today to lighten it up and make it easier to move. It is belt driven and so the chuck is threaded on. The chuck wouldn't budge. There is a lever that locked the spindle by engaging two gears. I tried using a drift and hammer to break the chuck loose. I was afraid to hit it to hard because I don't have much faith in those cast iron gears. Are there any tricks to getting it off or is it bigger hammer time?

I would also like to find a manual. I downloaded one from Enco that looks right but the PDF is very poor and hard to read. The lathe is a Morgon CBL-940 that was imported by Frejoth from Taiwan. It looks similar to several of the Chinese imported 12x36 belt driven lathes. Anybody have a lead on a manual?

floodgate
11-29-2007, 11:35 PM
Trailblazer:

It is a little bit risky, though I have done it many times: clamp a solid metal bar about 15" - 18" long crossways between the jaws (with a 3-jaw, it will be a bit off-center), up solid against the face of the chuck, most of it sticking out towards 10:30 o'clock as seen from the tailstock, two jaws under and one over the bar. DO NOT engage any of the gears. Whack the end of the bar lightly but solidly counter-clockwise with a lead or dead-blow hammer (or a heavy chunk of hardwood), and the inertia of the mainshaft should pop the chuck loose. You can also tighten a screw-on chuck, to keep it from unscrewing itself when running in reverse, by whacking it in the opposite direction. At most, you may ding the jaws or their seats in the chuck, but that's an excuse to replace it with a good "Bison" or similar brand one.

floodgate

leftiye
11-30-2007, 03:31 AM
If you can get a way to lock the spindle so that you can spare the gears (good steel gears, or?) then you can bang away at it. Within reason, no sledge hammers! You'll have to calculate how much damage you can do to the gears and spindle and chuck and how to proceed. I do prefer the lever, and impact method floodgate mentioned to direct banging on the chuck (unless a deadblow hammer is used), and also prefer this to the 10 foot cheater bar method. You can probly loosen the threads better with impact than pure leverage.

Buckshot
11-30-2007, 03:56 AM
.............My lathe has an L00 spindle nose so I have no direct experience with threaded on chucks. However, to loosen the big ring nut used to tighten chucks and stuff to the spindle, I put the lathe in back gear to lock the spindle. There is a large spanner wrench used on the nut. I just pull lightly to load the meshed teeth of the gears, and then heave down on it. It's about 18" long.

If you do end up with a bar in the chuck jaws and locked with the backgears, I'd load it first before applying any impact to the bar.

The guy I bought my lathe from has a 50's era 11" Logan with a threaded spindle nose and he does his as I do mine, locking the backgears. However he uses a big strap wrench around the chuckbody. I'd sure hate to spring the jaws or dint-ding the slots they ride in, but I've heard of clamping a bar in the jaws.

Great news on getting the lathe! Now comes the fun part! Tooling it up :-)

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

richbug
11-30-2007, 08:02 AM
I worry about breaking a tooth off of your back gear assembly if you had to beat too hard.

I'd use a hardwood lever myself to avoid damage to the chuck. a 2x2" chunk of oak with take a lot of abuse.


My current Clausing lathe has an L00, and I use a spanner wrench in a similar manner, don't have to get it terribly tight.


My old South bend has a screw on. I used to use a 1" hardwood dowel in it with it locked in direct and backgear at the same time.

Morgan Astorbilt
11-30-2007, 09:18 AM
My 12-1/2"x48" Cincinnati Traytop has an L-0 spindle, but my old Clausing 12"x36" used to have a threaded one, as does the 12"x36" Delta lathe I now use for polishing barrels.
I do as Richbug, and use an oak bar with the lathe in back gear, to break it loose with a quick jab. This is a no brainer, the lathe gears take a much heavier shock when making interrupted cuts, as when turning a square piece of stock. You can even, with a 2"x2" piece of oak or hickory, clamp it between the jaws and at slow speed, put the lathe in reverse, and let it hit the ways.

Morgan

slughammer
11-30-2007, 09:32 AM
For my chiawaneez 3 in one machine I used a 1/2" allen wrench. Chuck on the short end and then use a fast hammer on the long end.

Trailblazer
11-30-2007, 01:33 PM
I am worried about breaking a tooth off the gear so I will try it with it out of gear. I have a piece of square bar stock I can clamp in the jaws. The 4-jaw is on the lathe and that is the chuck I will be using so if it is to hard to get off I will leave it.

It has the normal attachments: face plate, 3 & 4 jaw chucks, steady, follow, drill chuck, and live center. The only thing missing is the center for the spindle. There are a bunch of tool bits too. The thing is filthy! Ways are coated with dirty oil. It does not look like it was used a lot so hopefully the lapping compound on the ways didn't wear them down to much. There is still cosmoline in places. Everything still seems tight and there are no dings or dents in the ways. The gears are heavily coated with dirty grease so I don't really know if they are steel or cast.

I am also getting a Rong Fu RF-30 mill in the deal. It is a bench top mill on the heavy end of the bench top scale. There are a bunch of cutters, parallels and clamps with it. It is also filthy but doesn't look to have been used hard.

In addition there are several mikes, indicators and miscellaneous machine shop tools. There are a lot of reamers and some drill bits. The stuff must have come from a retired machinist originally. I also got several molds and a couple lube sizers-one Lyman 45 and one 450 that is missing the lever.

The stuff is from one of our deceased club members. There is a lot of miscellaneous reloading equipment and gun parts too. Everything is filthy and most of it was used hard and is scattered all over the garage, a shed and the back yard. Dies are not in the boxes and are everywhere. The widow wants to get rid of the stuff but it is an intimidating mess. I am tempted to make an offer on the whole lot but everything needs to be sorted out and cleaned before it is saleable. I am not sure it would be worth the effort and I don't have a lot of room for it either. On the other hand I suspect that whatever we don't find a home for will end up in the dump and I wouldn't like to see that.

454PB
11-30-2007, 02:15 PM
My current lathe has a bolted chuck, but back when I was running a South Bend, I used the back gears and a hardwood stick as previously mentioned. I'd take all the slack out of the gearing, then a couple of smacks with a 3 pound hand sledge would loosen it every time.

Sounds like you fell into a lucky mess. I enjoy rooting around in old treasure piles like that.

floodgate
11-30-2007, 08:29 PM
Trailblazer:

Lotsa good advice; thogh I'm still goosey about loading the gears and prefer to use "inertia". (Ackshully, I often cheat and just stick the chuck key in one of the squares and tap on it, and that usually does it.) But it sounds like you fell into a good "starter set", and we look forward to having someone to help take the load offa Buckshot - his "lead times" are stretching out. (Smiley Face!)

floodgate

Trailblazer
12-01-2007, 11:00 AM
I don't know, that Buckshot feller is a tough act to follow! Anyway, I have to get my project backlog cleared up. For starters, I have six rebarreling projects waiting. Then size dies and a bunch of other little projects. It's going to be fun!

I have been looking for a lathe for a long time but I haven't really had the time to deal with it. I do now and everything just came together. It's a good deal but it is depressing digging around in the deceased's stuff. We both shot silhouette for many years and he was a good natured fellow. I do miss him.

Bret4207
12-02-2007, 09:38 AM
Sounds like a good haul. Maybe this is the excuse you needed to buy that parts cleaner set up and pressure washer!

BTW- I'm still looking at a Frejoth 13x40. Just waiting for the crazy old coot that owns it to get out of jail.....

Trailblazer
12-02-2007, 01:55 PM
I have a parts washer and pressure washer. I need a steam cleaner for this one! Probably just going to be rags and brushes with solvent though.

From what I could find on the net the Frejoth lathes are decent mid range imported lathes from the '80's. It isn't a Moriseki but it is a cut above the current Chinese imports. There is a manual for the mill and stuck in that manual is a "Lathe Accuracy Test Report". Wonder if you get one of those with a new Harbor Freight machine? The report has a date of "1986 4".