Old fart needs help/advise (again)

[pandreasen]

Some years ago, I bought a precision Jacobs chuck (#JKP-130-J33 Old style black/satin)
Well I never really used it so I stored it well for later use. NOW, I find that Jacobs recommends CLOSING the jaws before either disassembling it or whatever. Well I left it cranked wide open. CANNOT move jaws. Period! I soaked it in kerosene (Jacobs recommendation) for a few weeks and got so I could unscrew the the front sleeve portion, but can't take it apart as the jaws WILL NOT MOVE! Not sure why or what to try next. The most surprising thing is that Jacobs still sells that model (now all pretty satin finish) for just under $300. A LOT less than I paid several years ago. When I asked them if I could send it back and pay to have it rebuilt, I was told (unbelievably) that Jacobs does NOT REPAIR THEIR PRODUCTS SUCH AS CHUCKS! I would just have to replace it! Seriously! I couldn't believe it so I called again and got someone else telling me the same thing! They have a technical paper on disassembly (in closed position) of a WORKING chuck for rebuilding, but zip for help or even advise (other than soaking it) in repairing it.
Does any member (or alien, or ...) know how to get this sucker apart? I hate & can't afford to just throw away several hundred dollars of unused equipment. Military retirement only goes so far!

 

[Lo-Fi]

Did you leave it completely open? If not, have you tried using a hammer and brass drift or similar to try and shift the jaws a little? Anything to break the dried up oily gunk that's no doubt glued it all together. Gentle heat may also help. Though having said that, I'm not 100% sure it's vital to have the jaws closed to disassemble. Have you tried drifting the outer case off yet as it is? Hopefully someone who's disassembled one more recently than me will chime in with an answer on that.

I'm sure you'll get it moving.

 

[markba633csi]

I'm sure some soaking and heat will get it loose, give it some time. Liquid Wrench be very, very good to me
-Mark

 

[mikey]

I just looked at the Jacobs paper on disassembling this chuck and it looks suspiciously like an Albrecht design. My suggestion is to remove the knurled collar at the back, then make a fixture to hold the body in a vise so you can use a strap wrench on the knurled hood of the chuck, the part you grab when using it. It should be a right hand thread. If you can break that hood loose then you should be able to get it apart, regardless of the position of the screws. The only thing I can think of that would require you to have the jaws closed would be the position of the leadscrew in the threaded inner body but even then I think if you can break the hood loose, this would allow you to get those jaws freed up enough to move them.

 

[extropic]

I had the same situation recently with a NOS (very old) 1/4" Jacobs. Couldn't budge it (as received). I soaked it in mineral spirits solvent for a few days which allowed me to key crank it a little. More soaking, then squirts of aerosol brake cleaner to remove residue. If you have an ultrasonic cleaner, it shouldn't take long if you put the chuck in a jar of solvent placed in the ultrasonic.

 

[bobl]

Some years ago, I bought a precision Jacobs chuck (#JKP-130-J33 Old style black/satin)
Well I never really used it so I stored it well for later use. NOW, I find that Jacobs recommends CLOSING the jaws before either disassembling it or whatever. Well I left it cranked wide open. CANNOT move jaws. Period! I soaked it in kerosene (Jacobs recommendation) for a few weeks and got so I could unscrew the the front sleeve portion, but can't take it apart as the jaws WILL NOT MOVE! Not sure why or what to try next. The most surprising thing is that Jacobs still sells that model (now all pretty satin finish) for just under $300. A LOT less than I paid several years ago. When I asked them if I could send it back and pay to have it rebuilt, I was told (unbelievably) that Jacobs does NOT REPAIR THEIR PRODUCTS SUCH AS CHUCKS! I would just have to replace it! Seriously! I couldn't believe it so I called again and got someone else telling me the same thing! They have a technical paper on disassembly (in closed position) of a WORKING chuck for rebuilding, but zip for help or even advise (other than soaking it) in repairing it.
Does any member (or alien, or ...) know how to get this sucker apart? I hate & can't afford to just throw away several hundred dollars of unused equipment. Military retirement only goes so far!

View attachment 328932

My be trying WD40 or liquid wrench cold be little rust got in good luck


Sent from my iPod touch using Tapatalk

 

[bobl]

Some years ago, I bought a precision Jacobs chuck (#JKP-130-J33 Old style black/satin)
Well I never really used it so I stored it well for later use. NOW, I find that Jacobs recommends CLOSING the jaws before either disassembling it or whatever. Well I left it cranked wide open. CANNOT move jaws. Period! I soaked it in kerosene (Jacobs recommendation) for a few weeks and got so I could unscrew the the front sleeve portion, but can't take it apart as the jaws WILL NOT MOVE! Not sure why or what to try next. The most surprising thing is that Jacobs still sells that model (now all pretty satin finish) for just under $300. A LOT less than I paid several years ago. When I asked them if I could send it back and pay to have it rebuilt, I was told (unbelievably) that Jacobs does NOT REPAIR THEIR PRODUCTS SUCH AS CHUCKS! I would just have to replace it! Seriously! I couldn't believe it so I called again and got someone else telling me the same thing! They have a technical paper on disassembly (in closed position) of a WORKING chuck for rebuilding, but zip for help or even advise (other than soaking it) in repairing it.
Does any member (or alien, or ...) know how to get this sucker apart? I hate & can't afford to just throw away several hundred dollars of unused equipment. Military retirement only goes so far!

View attachment 328932

My be trying WD40 or liquid wrench cold be little rust got in good luck


Sent from my iPod touch using Tapatalk

 

[middle.road]

mineral spirits, or liquid wrench oughta do it.
I've had a few brought back doing it that way.
Had one 3/8" Albrecht that must have been sitting for a long time before I got it. Wouldn't budge.
Dropped in some mineral spirits for a week and it came out functioning.

 

[Saguaro Slim]

Kroil (pricey and stinky)
Homebrew 50% acetone / 50% ATF

 

[NortonDommi]

I make my own penetrating fluid of a 1:1:1 mix of Kerosene: ATF: Diesel and I have an old deep fryer full of it that smaller seized items go into. I heat up to around 140 -160 degrees C,(284 - 320 degrees F),for an hour or so then turn off and let cool overnight.
The auto-ignition temperature of Kerosene is 295 C or 563 F so even going up to 200 degrees is O.K. but it pays to keep hardening and temper in mind. https://www.safetystoragecentre.co.uk/advice/Auto-Ignition-Temperature-5.html
Amazing how many things I've recovered. Old dried oil and grease really can only be shifted with heat or much brute force.
The heating and soaking in a solvent that is also a lubricant dissolves the old deposits and allows a lubricant layer to coat the parts.
Kerosene or Diesel straight gently heated works great to but Kerosene works best.
Nice looking chuck I hope you save it.