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3 PT PTO driven winch
I'm building a 3 pt pto driven winch that is using a worm gear driven winch drum. Going to using this to skid logs up a hill. I got a few questions. What would be a good feet per minute speed for the cable? Right now with the ratio I have it will be 10 FPM at 1400 engine rpm's. and 22 FPM at 3050 engine rpm's which is 540 PTO rpm's. Does this sound good? I have seen speeds as slow as 3 FPM and as high as 40 FPM? Log skidders FPM can go over 100 FPM. Question #2; The standard store bought winches talk about 8000 - 10000 pounds of pull on a 5/16 cable, the breaking strenght of this cable is 9800 pounds. Anyone have any idea why or how they can spec the winch for these loads ratings?
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3 PT PTO driven winch
I think there's a LOT of creative advertising in the 4x4/atv winch products. Some ads equate pulling power to the weight of the 'rolling load', which is very deceptive. If some of these winches really had the capacity they claimed, there'd be an awful number of amputees around.
Please don't take me wrong, but you're beginning a very dangerous project. Small winches like the Farmi come with remote winch controllers, guards, slip clutches, stabilizers; cable and fittings appropriate to the load. It could cost more to build one unless you have a real good source of parts. If you damage the PTO or yourself, the cost easily could exceed a new winch.
Good Luck, bliz
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3 PT PTO driven winch
There is a lot of difference in speed as well as strength from an empty drum vs a full drum.
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3 PT PTO driven winch
Having been an avid off-roader, the higher-end Warn, Ramsey, Superwinch etc. winches are rated for actual pull/lift, not "rolling loads" which can be a fraction of the rating. Boat winches however ARE rated for floating (rolling) loads. Wire rope cable is typically rated by a factor of 3 - 4 times LESS than it is advertised for safety. Typically what you are looking at is "working load" not "breaking strength" as there are many factors that could be represented by breaking strength--such as shock loads versus having a load hanging from it, say from a crane, and the like.
Rather than go with a PTO drive why not use a hydraulic motor (used about $100-$300---get one off a wrecker/tow truck) powered off the rear remotes. Then you can get torque AND speed when you need it. There are hydraulic winches used on Jeeps that run off the power steering pump (Milemarker is one maker---I think they are in Florida).
For cost savings you might want to consider using a type of winch used on ships called a "capstan". This is a drum that you wind the rope around a few times. As it rotates constantly you control how fast the line speed is by pulling on the free end (loose end) of the rope (friction causes the rope to wind). That way you don't need a take-up drum (which you can still do but it could be a non-powered reel instead). You can use as many feet of rope you can haul because it doesn't store on the capstan. The only downfall with capstans is there no direct braking of the rope unless you tie it off to something.
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3 PT PTO driven winch
Some general thoughts are that what's reasonable for speed depends on the pto hp. It could be estimated by the load and final gear ratio including drum diameter at pto rpm, which likely is where the pto hp is speced for the tractor. I can't get my head around everything that would be needed or the particular formula this morning.
Cable comes in all sorts of different types and grades and 9800 lbs. nominal strength is typical for garden variety 5/16th IPS cable--I don't know what IPS means and fiber core is rated less. A type of cable called rotary swaged is common in logging since it has good crush and abrasion characteristics but it can't be used with swivels.
It sounds like a winch rated for 10,000 lbs. pull would break that cable before breaking the winch. that doesn't sound like a good idea since snapped cable flies around. I've heard more extreme differences between nominal strength and working load ratings than Green mentioned but it's the same idea. Working loads of 20% are fairly common I think and something in the design would have to limit the pull to something realistic.
I imagine the winch would have a butt-plate that can be assumed immovable under load but I'd worry about the top-link bracket's ability to withstand tension produced by a winch of that rating.
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3 PT PTO driven winch
Lots of different wire rope construction. IPS is Improved Plow Steel, there is also XIPS and XXIPS (eXtra Improved) available. The 3/8" cable Farmi uses is rated 13,110 lbs breaking (nominal) strength.
For crane service working load is usually nominal/3.5 , if an anti-rotation type rope is used divide by 5 instead of 3.5
Here's a link that has prices.
bliz
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3 PT PTO driven winch
One thing you might consider is what the old timers called a cable jammer. My brother still uses one on his JD 350 crawler. The cable winch drum is attached to a truck brake drum. The inner part of the brake (holding the brake shoes and the slave cylinders) that is usually stationary is constantly turning. There is about a 10 to 1 reduction in PTO speed by chain drive. Pulling a lever attached to a brake master cylinder pushes the brake shoes into contact with the brake drum which turns the winch drum. If you let go, the brake shoes release and it stops winching. Also when you are not pulling on the lever the winch free wheels for you to pull the cable. It's actually relatively safe. You can stand off to the side to operate it.
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3 PT PTO driven winch
I haven't heard of a jammer. It sounds like one of the good old ideas that still work just fine.
Thanks Bliz 'improved plow steel' now why didn't know that? I really did a web search on IPS and came up with a bunch of computer stuff. Yes my 20%, or divide by 5, figure did come from a table for non-rotating cable.
For estimating realistic draw rates, I'd solve for torque given the tractor's pro HP and 540 rpm. I think that's torque = 5252HP/540 but memory and early mornings don't always go together. I'd then multiply that torque by the final gear ratio of the winch drive with a full spool reduced by a guess for loss. That should give torque at the spool. RPM times the gear ratio would give spool rpm. The spool circumference at that speed would give the draw rate. I think that's a decent way to get an idea of the max performance to expect. Lower winch gering would give stronger pulls but at slower rates.
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3 PT PTO driven winch
Pardon me for dragging up a old thread.
I was driving by a farm yesterday and there was a winch for sale at the end of the driveway. $175 was the what the sign read. The farmer OFFERED to sell it for $100. Sold! The winch is totally complete with frame, cable and a capstan drum! The winch appears to be a 20,000 lb unit by Tulsa. Max input speed is 600rpm. Static torque input is 5,304 inlbs. The winch weighs around 500lbs. So I'd like to mount it on a 3pt hitch. I can put a 540rpm pto shaft right on the winch which will give me the correct speed and direction. The question is if my tractor has enough power to turn the winch. I only have 13pto hp at full throttle. Now I do have a 3speed pto (540, 750, 1200) but the other speeds are faster so there will be no mechanical advantage unless I use a chain drive reduction. Using a speed reducer will work ok with my current tractor but any other tractor will result in slow pull speeds. Thoughts?
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3 PT PTO driven winch
I think you got a smokin' deal on the wench but what you are proposing to do in my opinion is just too much for your Yanmar to accomplish. (this is unless you plan to mount this wench to a MUCH larger tractor)
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