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Capstan winch practical for long 2,000' towing up 1,000'?

Capstan winch practical for long 2,000' towing up 1,000'?

Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
Exploring practical options for towing a small/light flat bed trailer up mountain side that while flat at bottom gets progressively steeper until almost vertical right before it rounds out cresting at the top.

Maximum design load not to be exceeded, not including trailer weight which has not been selected yet, is 2,000 lbs of building supplies secured onto trailer bed. Total distance travel will be 2,000' from bottom to top that's at an elevation 1,000' above.

I was looking at anchoring rope or cable (if any capstans do steel cable) at the top and having the gas powered capstan be secured in the front of the trailer with a roller guide for the rope/cable to run through on top at the front of the tongue of the trailer. But, that might be a little too much excitement for the operator, so let's just figure the engine/capstan is anchored at the top, pulling the trailer up.

I started thinking capstan winch cause drum winches become less effective as their drum fills up and it's near at the top end it would need to be most effective. Some of the capstan winch outfits talk about limitations on rope length of 500-600' because of stretch. Some talk about different or larger ropes maybe less so.

If above might be practical, what minimum size combinations of engine/torque/capstan/rope should I be looking at? Is steel cable even an option with any capstan rigs?

If above is impractical or not advisable, what might work instead to accomplish the task?
Thank you for your response.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

Have a look on the net for "drumless winch"

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Capstan winch practical for long 2,000' towing up 1,000'?

The US Army are masters of lifting, winching and supply transport. They are the best in the world.....

Consider purchasing a used truck winch system many of which are available over the internet.

You will still need some type power at the top of the mountain. What are you going to use ?

You might consider a commercially available log skidding winch, but you may be limited by the maximum cable length.

As stated above, the 2000 lbs load is no problem..... the 2000 ft pull length is..

http://www.hud-son.com/products/product-detail/85m...

Perhaps you can consider a pull of your load to an intermediate point. Stop then pull again.....

Please respect us by completing this thread....

Tell us of your final solution

MJCronin
Sr. Process Engineer

RE: Capstan winch practical for long 2,000' towing up 1,000'?

I'd take a serious look at a long length of roller chain, anchored at both ends, with a bit of spring at the bottom just to keep it from getting too tangled. Coupla idlers to force engagement of the sprocket on your mobile winch, and you're done.

Or put the winch at the top of the hill and use two cars, as in a funicular.



Mike Halloran
Pembroke Pines, FL, USA

RE: Capstan winch practical for long 2,000' towing up 1,000'?

" .... funicular..."

She was my favorite mouseketeer too.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

Consider a helicopter lifting service, safe, fast and probably less expensive.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
Thank you everyone for your feedback, please keep suggestions coming, it's much appreciated!

Naturally, I'm trying to keep my costs down and final set-up as close to KISS principle safe to do.

Ideally, I'd like to find a more powerful version of this inexpensive portable capstan unit here...
http://portablewinch.com/en/products/PCH1000.html



Unfortunately, at only 2.1 hp, it is only rated for...

Max. pulling force 775 kg (1700 lb)
Rated lifting cap 250 kg (550 lb)

I'm still looking for larger gas powered capstan unit, but so far am only seeing a few out of Australia
that are mid-sized larger and not way too big overkill and expensive. I'm thinking that a drum winch,
big enough to hold 2,000' ft of cable would be even more expensive, but am willing to re-look at that.

I took another closer look and there is possibly another place to go up with some clearing work first
that, while length of rope/cable (2000') and final elevation gain (1000') are the same, it's a much more
gradual slope all the way without an, as extreme, vertical near the top. I'd figure worse angle there, at
near the top, is 45 degrees. If I can keep trailer under 1,000lbs, then combined with maximum load atop
it of 2,000lbs, I'd be looking at 3,000lbs maximum rolling load.

What do you figure my winch, be it capstan or drum, needs to have, with safety margin, as a minimum for
max pulling force and/or rated lifting capacity?

Thank you for responses.

- Shane



RE: Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
Best maybe to endure more trips by dropping the combined trailer weight and maximum required load to under 700 lbs by using this...
http://www.bikesatwork.com/bike-trailers/specifica...



It's toughest configuration is rated for handling maximum 600 lbs of cargo and that particular trailer itself weighs just 70 lbs.

If we went that route, do you see any reason why that capstan winch above, the http://portablewinch.com/en/products/PCH1000.html
rated at Max. pulling force 775 kg (1700 lb) and Rated lifting cap 250 kg (550 lb) couldn't readily handle worst 45 degree incline?

I'd just have to figure out a skid plate for it for whenever the tongue was on the ground. The tires can be placed more forward or
back and loads situated so that we could strive to keep tongue from excessively scraping. That'll take some experimentation. Also,
lowering it straight back down hill will probably be a challenge, but most any trailer we'd use probably would be, too.

What do you think?

- Shane

RE: Capstan winch practical for long 2,000' towing up 1,000'?

Remember to include the HP required as a factor in how long it will take.

Supposing a 500# trailer with a 2000# load -> under 3 inches/second or 13 feet/minute per 1 HP, not including losses elsewhere or the weight of the cable. The 2HP unit would take something around 1/2 hour if it was set to take the 2500# load.

Have you considered making 2 trips?

RE: Capstan winch practical for long 2,000' towing up 1,000'?

[quote=3DDave]Have you considered making 2 trips?[/quote]

I'd go further and say determine the heaviest piece (maybe a truss?) and get the load weight down to where a good quality rope would work with appropriate block and tackle. Then make multiple lifts. Surely the time spent getting materials up is small compared to the total construction time.

How are you going to get a trailer to go downhill along the desired path?

RE: Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
Thank you for comments, they've helped me zero in on something more practical, as described in my last post above.
Smaller, cheaper set-up carrying much smaller maximum loads more frequently.

I'd only add that I'm looking at Samson Stable Braid in 1/2” diameter, it's a double-braid, 100% polyester rigging
rope with "exceptionally low stretch" they say, and a breaking strength of 10,400 lbs. It's been used and praised
by other owners of same capstan winch specified above.

That reduced load and requirements on winch and rope and reduced cost of all components is attractive, if it'll
both work and with sufficient safety margin. My intention at this point is, with capstan winch anchored atop, I'd
draw up the cart. An available option, for little additional $, I'd likely do, too, is to get second set axle/tires
so it's much less of an unstable rickshaw. And, while getting rig back down hill can be done in a very slow speed
controlled manner, steering could likely be an issue requiring trial & error experimenting with it.

As described in post #7 above, along with what I've also shared here, does this set-up start to look like it oughta
do thejob and with a sufficient safety margin?

- Shane

RE: Capstan winch practical for long 2,000' towing up 1,000'?

Samson is probably a good choice of rope, but why polyester? Why not one of the hi-tech fiber ropes? Samson has many.
When ropes break, even "low-stretch" ropes, they recoil violently. Not that you care when your trailer falls 1/2 mile down a hill.
Synthetic ropes that are dragged on the ground and spend long periods of time in the sun (UV) need to be de-rated, and retired after a limited life.
Consider a factor of 3 derating on the load, and a life of 1 year, and still provide for it to be cleaned regularly and stored indoors when not in use.

Personally, I would second the "chain hoist" arrangement that was proposed earlier. Much easier to design for safety, and lasts a long time.

Are you going to use this one time only, or frequently for years?

STF

RE: Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
SparWeb, To start, I'd use it quite a bit, multiple runs daily, though it'd be used just 2 or 3 times monthly after construction completed and for as long then as still viable and safe, until it would need to be replaced. Rope would be stored out of the elements when not actually in use. That particular rope came highly recommended by users of the same capstan winch I'm looking at and seems good cost/value, though they did brag on the others, too, if you can afford them.

I really don't get the 'chain hoist' appeal, but maybe that was my fault in how I initially described the project in wanting to have a system that'd get at least a 2,000 lb load up the hill. It was not be a one-time trip. That's not all I want or need to get up there, that's just the minimum I was aiming for with one load. I've since resigned myself to a smaller load of 600 lbs and will just have to make more trips then, but save on overall cost of system to do so.

Make sense?

- Shane

RE: Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
MintJulep, I like that, had thought about laying track, but did not know there was any simple small monorail.
Could help pay for it charging for rides, nah, don't need liability & loss of privacy, the point of mtn top.

- Shane

RE: Capstan winch practical for long 2,000' towing up 1,000'?

Considered twin winches (whatever type) where one has 2000' of rope/chain but only has a working range of 1000'? Then you could lock it, go down and swap ropes to an identical winch that has 0-1000' working range.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

compare cost to helo lift it to the top

RE: Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
After construction loads gotten to top, want to keep system in-place for later re-supply, so helo might be good initially, but impractical later. Also, expense of helo might be better to spend on more robust and permanent system.

Twin winches might be doable or only way to do it on the cheap, still exploring.

Thanks all for comments and suggestions, it's been much appreciated!

Will check back later with update, if/when attempted.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

How are you planning on keeping the trailer on track during the runs up and down the mountain? I am assuming that you don't have some perfectly straight and level path to follow so the trailer will want to take some short cuts/ detours. A rail like Mint posted would work great, or you could use a winch with a separate guide rail or rope or barriers along the path.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

I like some of the other ideas better but an alternative is a double drum winch. The cable is in a loop and spools into and out of the drums. So there is no limit to cable length and the rated force doesn't drop due to cable layer buildup on a drum. The drawback is you need a return pulley.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

It is hard to suggest things without seeing the site, but would a Zip line with a cable trolley be a better bet. By anchoring the line further out you would have a reduced gradient and an easier pull. The timber companies use these devices to get logs out of difficult terrain.
Hitching the end of the cable to a suitable deadman.
B.E.

You are judged not by what you know, but by what you can do.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

(OP)
hendersdc, the trailer loaded probably won't be moving up hill faster than somebody could walk alongside it, nudging it, to keep on track, communicating with top winch operator to pause, if needed, etc. The down trip would be bigger concern of drifting or wandering, with trailer being lighter, but at only 70 lbs empty, again somebody tending to it should be able to readily nudge it straight, as needed. That's the plan, anyways.

BrianE22, double drum, had not thought of that, will look into it, thanks.

berkshire, zip line was actually my first approach, imagining a fast/fun 'commute' off the mtn, too. Looked at the logging rigs, too, but discovered that the weight and distance combination created excessive dip in the line unless I went really heavy with the cable and installed top and bottom towers to assure trolley cart would not be dragging on either end. Expensive and much more involved as I got into the details, so started looking more at KISS principle of one smaller/cheaper line, one lightweight cart, one inexpensive top winch dragging it up hill. More trips reqd, cart tender up & down, too, but much simpler and cheaper, if in practice it worked out OK.

RE: Capstan winch practical for long 2,000' towing up 1,000'?

Shane - on the helo; they use them to harvest small pine trees for Christmas. They are expensive by the hour, but they are also fast. I don't think they would be a great fit for your circumstance; just pointing out they may not be as costly for difficult work as one might imagine.

Oregon Christmas Tree Harvest With Helicopter. Amazing Pilot!
https://www.youtube.com/watch?v=08K_aEajzNA

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