Steel Worm Gear for the Braden LU-4?

[Elwood]

Found this on e*ay: http://www.ebay.com/itm/191990757321



A steel worm gear supposedly made for the military to replace the bronze gear in the Braden LU-4 winch. Anyone ever seen or used one of these? Is this legit?

[DJ]

Is the bronze gear a built in weak spot to be sacrificed ,saving the rest of the gears?

[just me]

No, the shear pin is the built in weak spot. A worm or bull failure would be catastrophic.

[just me]

I always ASSUMED the bull was bronze as a rust preventative measure. A steel or iron gear would be partially out of the soup for long periods of time and could rust. Everything above the oil line is non ferrous in my two winches.

[Elwood]

Is the bronze gear a built in weak spot to be sacrificed ,saving the rest of the gears?

Intentionally or not, it seems to work out that way. The worm (the spiral gear that drives the worm gear, and the only other gear in the winch) is steel, so the bronze worm gear teeth usually wear to a knife edge. Using the wrong lubricant in the winch doesn't help, of course. But given the cost of the bronze worm gear, that seems like an expensive gear to sacrifice.

I'm wondering if these steel worm gears are a genuine Braden part, made as replacements because the bronze gears were too weak in military service? Or maybe they're not factory parts, but made by someone else, and could cause problems when used in the winch. If Braden specified bronze for the worm gear material, there must be one or more reasons for it. Maybe they're no longer good reasons, and the steel is actually better, but I'd want to know before I swapped in a steel worm gear.

[just me]

Given the very limited use my winch gets, I didn't hit BIN on that auction. My gears are perfect still. If I was using it to run a derrick or plow, that would be a great replacement part. In the end, given the cost of a bronze replacement, if mine wears out, I'll just hob out a new one for myself. I have the machines to do it. Would probably have to have a hob ground as I am sure I don't have one for this application.

[Elwood]

No, the shear pin is the built in weak spot. A worm or bull failure would be catastrophic.

A gear failure in the winch would certainly render it unusable, but would it cause an uncontrolled unspooling under load? Does the angle of the spiral teeth on the worm essentially prevent the drum from turning (assuming the winch clutch is engage), i.e. the worm on the input shaft can turn the worm gear relatively easily, but the worm gear cannot easily turn the worm?

I always ASSUMED the bull was bronze as a rust preventative measure. A steel or iron gear would be partially out of the soup for long periods of time and could rust. Everything above the oil line is non ferrous in my two winches.

Now that makes sense.

[Jess]

Bronze has been pretty much the standard for this type of application for many years. Most if not all of the Braden, Tulsa and similar winches have bronze gears. WInches, and rotator gears for manlifts and similar equipment are bronze. I have collected many sets of gear and worm from rebuilds that can still be used in projects. Many were replaced as part of lifespan rebuild and show very little wear. Ease of machining, and wear factors may be a consideration but I can't see why a properly made steel gear wouldn't work as well or better. I think most issues with these gears comes from improper initial setup and lubrication. Most of our winches will never do a 100 hrs of real work but failure under load could become catastrophic. I have a couple of 'junk' LU4s that were ridden hard and put away wet. I got them for parts but abuse and lack of proper lubrication killed them both, not long term use and normal wear. Just my opinion.

[milstencil]

Holy crap!
http://www.ebay.com/itm/Brass-Worm-Gear ... 3641.l6368
I think I'll take the spare I have and lock it up!
I was thinking of posting a whole lot of winch parts at a great price, but not now.
I'll hold on to'em.
Rick

[Elwood]

Holy crap!
http://www.ebay.com/itm/Brass-Worm-Gear ... 3641.l6368
I think I'll take the spare I have and lock it up!
I was thinking of posting a whole lot of winch parts at a great price, but not now.
I'll hold on to'em.
Rick

Sam Winer Motors is not what most people would refer to as a bargain store.

I don't know how many of those worm gears he has in stock, but I know I've seen that listing for a long time now. Asking $600 doesn't mean that he's selling any of them at that price.

[DJ]

No, the shear pin is the built in weak spot. A worm or bull failure would be catastrophic.

Sorry,never had a winch apart.

[Elwood]

An update on the steel worm gear question.

According to one of the technical support staff at Paccar (the company that bought out Braden winch), they never made a steel worm gear for the LU-4 winch, so this must be someone else's manufacture. It measures out almost identical to the Braden OEM worm gear, so it may be usable.

I found this from Machinery Lubrication magazine:

"Steel worm and steel worm wheel - This application does not have the EP [extreme pressure lubricant] complications of brass gearing, but there is no room for error built into a gearbox like this. Repairs on worm gear sets with this combination of metal are typically more costly and more time consuming than with a brass/steel worm gear set. This is because the material transfer associated with failure makes both the worm and the wheel unusable in the rebuild."

The current factory list price on a replacement brass worm gear for the LU-4 is...$1,453.68. Distributor pricing may be somewhat less. Sam Winer Motors is a Braden dealer, so maybe that $600 figure is the actual street price for a new gear.

Hard to believe that replacing both the steel worm and the steel worm gear would be more expensive than a new brass worm gear alone.