Braden AMS6 Winch assistance/advice

[Warren]

All,    Good morning ! Merry Christmas and Happy New Year ! 

Santa dropped off a Braden AMS6-15A winch.  Rated for 24,000 # pull according to the tag.  Apart from freeing up the clutch on the drum shaft, only one issue.  The worm gear only wants to turn in one direction....  turns freely one direction.  Feels like it has a lock pawl of some other kind of device to prevent worm gear turning back wards.  I can not see see any lever or push/pull device on the housing to reverse direction of wind/unwind.  Easy one way, ZERO back lash the other.

The obvious concern is it will be easy to open the clutch and let cable free spool off the winch with no load.  But, with a strain on the cable, how to "reverse direction" of cable travel ?  The service guy at PACCAR (owners of Braden and Gearmatic) was very helpful and emailed a PDF of the parts explosion.  The parts drawing shows a "worm brake" assembly.  But it appears to be more a friction clutch set up just to prevent free wheeling.  Nothing in the parts drawing looks like it is reversible for direction of wind/unwind.

I can't imagine that a winch with this capacity does not have the capability to reverse under load.  But I sure can't see how to do it.  All helpful advice/suggestions greatly appreciated....

Warren

[logwalker]

Is it a PTO or hydraulic winch? What did Paccar say about the operation? Joe

[Warren]

LW,   

It has a sprocket for schedule 80 roller chain on the input shaft/worm gear.  I was thinking to mount a reversible hydraulic motor to the frame with a short loop of chain to drive it.  But, it is not much use if I can not slack it off under load.

Warren

[mike_van]

Warren, I don't know what that particular winch was made for, maybe it's original use was one where it wasn't wanted to drive in reverse? Anyway, my 3 pt hitch log winch I made I put a hyd. motor on to drive it. It was too slow, and not enough pull. Last fall I swaped it over to pto, and in doing that I lost my reverse. Pto only turns one way. I've pulled some 200+ trees & logs since, and I just make sure I'm set up where I can back the tractor a few feet if need be to let the strain off. Once I get a little slack, I can pull the lever & freewheel cable if I want.  A winch that size, you must have a pretty good size tractor?  My 8000 lb Tulsa is on my IH 574, 52 hp - If I hang up a log, it'll easily pull the tractor backward. I've heard of backing up to a stump or tree to stop that, but if the logs that hung up, you gotta pull it a different direction or risk breaking cable, hitch, or ?

[Reddog]

Warren,
It sounds like the worm gear back lash may be out of spec.
Worm gears can lock up in one direction and work fine in the other if this is not shimmed to spec.
Usually is just normal wear and maintenance to re-shim.

[Warren]

Mike Van,  You hit the nail on the head.  Another FF member (who shall remain anonymous  ;D) had the same situation with PTO drive on a big winch and hanging up on a stump.  Maybe had to take a torch to the cable.  That's  what I am trying to avoid with a hydraulic motor.  Yeah, the 24K winch is more than I need for my tractor.  But I have a C70 knuckle boom to work with.  It wouldn't take a lot of work to plumb an additional circuit...

Reddog,  Thank you for the suggestion on shimming.  Looking at the parts drawing, I see one thrust ring on the drum shaft for side play on the worm gear.  I will start looking there.   Any sources on the web you could point me to that describe proper shimming and back lash for such a critter ?

[WH_Conley]

If ya get in the woods and get hung you can turn the PTO shaft backwards with a pipe wrench, just make sure that you are PUSHING the pipe wrench, not pulling. If in a bind, when the shaft moves, let go the wrench.

[Reddog]

Warren,
I haven't found any online info. :(

[Warren]

WH,  I will keep that in mind !

Reddog,  Thanks for looking.  I finally just tore it down and figured it out. It has a friction clutch to keep drag on the worm to prevent free wheeling unwind when no load.  The unit has set so long that the grease is like sludge. The friction clutch is gummed up to the point it does not slip at all.  I think a trip thru the parts washer tomorrow should fix that problem. 

Now I need an engineer, or at least someone with pratical experience with hydraulic motors and winches. The winch is rated for 24,000 lbs.  I am assuming that is first layer, maximum pull.  Spool diameter is 5".  Worm gear diameter is 7" with 34 teeth.  I dont think it matters, but worm major diameter is 3.5".  With 34:1 gear ratio, 7" drive gear and 5" spool, I "think" I should get 47.6 pounds of pull for every foot pound of torque applied to the worm.  Does this sound right ?  Or, am I missing something ?

Second question, if the calculation is correct, then I need a little over 500 ft lbs of torque to hit the winch's max rating.  What type of hydraulic motor would I need to genrate 500 ft-lbs of torque ?  This seems like a lot of torque out of a hydraulic motor.  Thoughts ?

Warren

[HOOF-ER]

Go to surplus center they have ft lbs listed for hydraulic motors.

[mike_van]

Warren, your math must be off, but I don't know where. Most hyd. motors are measured in inch pounds, not foot?  500 ft. pounds would be an incredible motor. 

[Warren]

Hey Mike,

Thank you !  That's what I looking for is the reality check.  I am "assuming" that 12 inch-pounds (or pound-inches) equals 1 foot-pound.  ie: a hydraulic motor rated for 1200 inch pounds will generate 100 foot pounds of torque.  Is this a correct assumption ?

Also, after doing more digging on the web, I found out that this particlar winch is only rated for 15k lb pull, not 24k, so input torque required to reach full rating "I think" is only 300 ft lbs, not 500.

At this point with 300 ft lb requirement, if 1 ft lb = 12 in lbs, then there are several Char Lynn motors on their site that fall into the usable range.  I may need to play with sprocket size to balance torque versus wind/unwind speed.  But, I think I am closer than before.

Thank you for your time to look over / critique my math.

Warren

[mike_van]

12 in. lb to 1 ft. lb.  is right Warren - What tractor will you run it on? How many gpm is the hyd. pump on it? 

[Warren]

Right now I have a 64 hp Long tractor.  Not sure the gpm.  But too much winch for the tractor, even with 1,000 lb of weight on the front.  Trying to figure out how to mount it on the C70 knuckleboom (already has pto hydraulic pump).  Have a 500 ft length of "lightly used" 7/16 cable.  The winch spool should hold 300 to 400 ft of the 7/16 cable.  The truck is not a serious off road vehicle.  But I should be able to get close enough to put a winch line on the trees I am looking at for the moment.  Idea would be to winch logs out of the steeper places to flat ground with the truck.  Then hook to the farm tractor for level skidding.

That's the thought anyway.  Should have the winch back together Saturday.  Then need to start hunting a hydraulic motor...