Jet 1236P

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spro
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Re: Jet 1236P

Post by spro »

If I had that issue, I would improve that finger knob handle instead of making it like it was. I can tell you from long experience, that finger knob only wants to unwind. It may not have been broken by bumping into something. It may have broke because some guy tightened the heck out it. This is time to improve it. It should have tactile shape and two piece. The knob is a sleeve on a shaft. Every tool from brace to beater has a floating knob or handle. The cross slide is the most tactile, delicate "feel" area and we don't need the dang knob sticking to fingers and unwinding.
If we look at quality equipment, the fixed wheel knobs are polished teardrop shaped and make perfect sense. The compound isn't too bad but the cross slide and carriage traverse handles beg improvement.
jcarmon
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Re: Jet 1236P

Post by jcarmon »

I just bought the same lathe, a 1977 Jet 1236ps from a wood working shop about 2 hours from home. It was covered so bad with sawdust and muck, the pictures didn't even look like a lathe. But when I cleaned it off, It still had the shipping grease on it. The plastic that covered the metal labels was still on it. The chuck, tool-post, and tail stock cleaned up nicely with CLR and a toothbrush. I painted the chip try Jet black, and am building a workbench for it now. It had this weird 6-1/2 inch 3 jaw on it that seems better than what Jet would have used. Its marked VANCO, and MADE IN JAPAN, with a number 5 on the opposite side of the number 2 jaw. Any idea where this chuck came from? Seems to be 60mmx8tpi on the spindle thread, with a MT5 spindle bore, and a MT2 tail-stock, with 4-1/8 barrel travel. I cleaned all the electrical contacts, and the wiring block in the back still has the little numbers on each wire. I could really use a collet device of some kind, and a follow rest. A second hand tool-post would be really useful as well. This is my first real lathe. I don't consider the CM 5980 3n1 combo much of a tool, but it served its purpose.
spro
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Re: Jet 1236P

Post by spro »

It seems your lathe is more closely related to mine than these later ones. Can't say better but the specs said they aged out the bed castings a long time before grinding them. These beds have 3 Vee ways and are hardened, mine shows no wear, except a stripe which indicates I need to remove a hard chip. I go two ways with this lathe. Overwhelmingly it serves my purposes and the Polish chuck it came with, is outstanding. It isn't the same as much better quality American or European lathes but it didn't weigh as much either.
Some of my earlier threads explain how I managed this lathe taken down and set into the basement. Tiny house, doors removed, reinforced stairway and help. Even then it was heavy. I never removed the head and the lathe tipped at point where it was turned to accept a rolling workbench. The "tip" required me under it a few seconds as to not damage my new lathe. It all worked well as was able to roll it to the same level lathe bench and place it. As crude as many old reviews say, my old Taiwan Enco ain't leaving my basement until I'm dead.
jcarmon
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Joined: Thu Jul 06, 2017 3:40 pm

Re: Jet 1236P

Post by jcarmon »

Ive been fairly impressed with this one. My indicator isn't good enough to measure any run out on this Vanco chuck, So I guess Ive got a keeper. One problem is the lack of usage. This thing is 39 years old, and I don't think its ever been cleaned. The head-stock was completely dry, and The original belt was dry rooted. The Napa here in town found me a new one in 5 minutes, and I got 3 quarts of 20w Motor oil, and a bottle of air tool oil. Two sanding blocks and a couple of 1 inch paint brushes, and shes starting to look good. I don't know why a shop owner would buy a 4800 dollar lathe in 1977, and then leave it in such a state.

here are some pictures of it the way i found it.

https://goo.gl/photos/M52AfreVhorHjDTXA
spro
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Re: Jet 1236P

Post by spro »

Hi James and Wow! Lots of cleaning up work but worth every bit. As dirty as it appears, I agree it has a long life ahead. Dust and dirty oil film isn't the same as rust. I bet it looks much different now. Yours is the one before mine. Same bed, tailstock, carriage. The head casting was elongated deeper to where a slanted front met the outer projection of the QCGB. This allowed the mechanical direction of the feed train as a lever and the power switch/ lamp and jog/stop switch in the face. The guts are the same.
jcarmon
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Re: Jet 1236P

Post by jcarmon »

I still consider myself a new machinist, even though this is my second lathe. I never thought, a professional, even a pro woodworker would ever allow a piece of equipment to get this bad. There is saw dust in every nook and cranny I've found. So far, Ive completely disassembled the tail-stock, cross slide, and tool post. Cleaned them with a brush and CLR, dried them by hand, or heat. I've reassembled them with a coating of air tool oil. The carriage is tomorrow, and I hope the QCGB is Monday. Not sure what to do about the spindle and motor assemble yet. I greased the spindle with some air tool oil, and turned it by hand until it turned freely, But the feed-screw, and threading-screw, look like I need to hit them with the power washer. He must have been using pure old motor oil on everything when he did oil it. Ive already painted the chip pan jet black. I think I'm going to paint the whole thing the same way Jet does their new Elite lathes. Red and black with some polished aluminum handles, and polished soft top jaws should look awesome in my shop. Should have my workbench finished by Monday. welders started on it yesterday. All cast iron work bench. Should weight about 1400 pounds, with the 1.25 cast iron top, and six 4 inch square legs.
spro
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Re: Jet 1236P

Post by spro »

You're really getting into the apron cleanup now and maybe haven't read this. This style has three traversing rods and the bottom one just allows the lathe to be forward/ Off/ Reverse from the apron. The top one is the lead screw for threading only. The middle one is for fine feed and there is an interlock to prevent the lead screw being clamped while the fine feed is engaged or vise versa. Problem is, sometimes that doesn't work and if you are the least unfamiliar, worm wheel gets buzzed off.
Going back to older,and even more accurate lathes, many of them shared the lead screw with the fine feed. That means the lead screw was slotted for it was always driving a keyed worm in the apron. There is no way it is best to have a slotted, toothed shaft digging into the clamping jaws, so jaws wear and so does the lead screw. These lathes have no slot in the lead screw and the clamping jaws and thread dial indicator gears hold up well because of that.
The 2nd rail; The worm is there and not always turning because Fine feed isn't always selected but that worm mates to a brass worm gear and That baby gets the shaft if the interlock is sloppy. Look that over good. :)
jcarmon
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Re: Jet 1236P

Post by jcarmon »

Man Have I had a day. I no longer consider myself a new machinist. I now know my lathe INSIDE and out. I tore the saddle down and reassembled it three times before I got it right. You were right about those brass gears. But the third time, I just went all out. Tore it back down, soda blasted the iron, and ran the brass throw the dish washer. Painted the iron with a good JET black car paint that my uncle gave me, and polished the brass with a soft rag and brass-o. Jet would make this thing a museum piece if they got their hands on it. Did the same to the bed, head-stock, tail-stock, and the steady rest. The QCGB was a little less trouble. The gear selector just refuse to go into A or B range. I found a bad spot on the shaft. Not sure what to do about that just yet, but after today, I'll figure it out. At least Ive got 24, 28, and 32tpi at my disposal. The bed, the covers for the QCGB, and the head-stock gears should be dry tomorrow. When I get this thing done, I don't know if I should use it, or just sell it while it looks so good. I have a heard time remembering this thing is 2 months older than I am. Manufactures data plate was still covered in plastic until today, made October of 1977. Couldn't figure out why all the metal plates were cloudy. It was the plastic they put on them at the factory. One thing I didn't replace was all the dang roll pins. They could have saved 100 dollar on the cost of this thing if they had just left half the roll pins out. As bad as an M-16 from the same year. I'm looking a tool post hot and heavy if anybody has one. This single tool post is big, but not want I need. The mount is a 2"x"2x.250" slot. My 3n1 had a 4 way, with a t-slot mount, so this one is a mystery to me. Update in the next 2 or 3 days. I hope to have this thing on a bench Wednesday night.
spro
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Re: Jet 1236P

Post by spro »

Yeah turret toolpost. You will surpass and be teaching others. I have one but not for you . I should've posted it years ago but rabid dogs would hunt me down.
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ctwo
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Re: Jet 1236P

Post by ctwo »

Can you post any pics of the inside apron parts? You're knocking on inspiration's door. My Jet is still sitting on the floor since I started this topic. I need to weld up the stand and get a motor installed. I even have a choice of 1HP single phase or a 3-phase.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...
spro
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Re: Jet 1236P

Post by spro »

Brush past some stuff. Those original totally enclosed, single phase motors weren't all bad. Maybe I was lucky but mine doesn't ask or lack anything. Powers right up and runs great. Many years ago I had the notion to rewire it to 220v but was waiting for the need to do that. It didn't happen. Its a fair large a@@ motor but doesn't draw too many amps on 110v.
There is another thing about these lathes and that is the bevel gears. These type gears would be in a tractor's transmission. Just a few but they can pull a smoking load .
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Rex
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Re: Jet 1236P

Post by Rex »

Those old Jet and Enco 10X and 12X lathes from the 1980s and 1990s are stout machines. I have had 3 so far, all with hardened beds and accurate as heck. For parts, Grizzly G9249 was made up until a few years ago, many parts fit those old machines.
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