Petroleum Jelly (PJ)

[Tim Stapp]

I've seen many posts here about using PT as a press lube, case lube and even as a part of cast bullet lube.

My first experience as an inexperienced 8 year old was going to the local hardware store to get bearings for my bicycle (I still remember Johnny Johnson's Hardware store with the nail kegs in a semi circle around the wood stove and the old timers sitting there curing the world's ills).

He would sell this innocent 8 year old one 410 shotshell at a time and a 50 round box of 22 LR (after receiving my Dad's permission, of course).

Anyway, he turned me on to using PJ for bearing grease for the bicycle wheel bearings and pedal crank bearings. Told me that my Dad's wheel bearing grease was too heavy and was causing my bearing failures because I had to take off any preload to make it anywhere reasonable to turn, thereby causing the bearings to fail.

In my professional life as an industrial machinery technician, I've found a multitude of uses for PJ, and because of this forum, added one more.

Thanks, Guys (and gals).

[RBHarter]

I never had bicycle bearing failures but we mostly had disk break and aviation grade grease on hand ....

It's 40% of my bullet lube .

[Ranch Dog]

Yep, not all grease is the same. I was watching our mechanic servicing the Bell 407 that I'm flying. He had a bunch of different grease guns laying in a lineup. He explained bearing loading and the effect grease has on it. He picked up the heaviest grease and said if he used this on the tail rotor driveshaft bearings, the bearings he was getting ready to lube, at about the time I was coming off the dolly and not quite translated to forward flying, I'd end up in a heap off to the side of the dolly. Those bearings would fail that quick.

PJ remains my favorite press lubricant.

[Tim Stapp]

Yes! Each if formulated to an application. I'm a field service technician on industrial material handling equipment. Different guns for different greases for different application. I always follow the manufacturer's specified lubrication requirements.

At the time that hydraulic spool valves were the norm (man I miss the control that an operator had with manual control valves) we used a rather light hydraulic oil. As the mfr. transitioned to solenoid actuated valves, they had to go to a heavier weight oil due to needing "more tolerance" because the solenoid activated valves were made to looser tolerances than the manual valves. I suspect it had to more with the older manual valve bodies being cast iron with steel spools and the solenoid activated valve bodies/manifolds being aluminum with steel spools.

I'm sure that aviation had much tighter clearances and had to deal with such temperature extremes. Beyond my pay grade:)