PTO Capstan Winch (from scratch)

[chim]

Nice project! A bit late for the party, but I have a few comments. We use pulling machines (Greenlee , Maxis, Condux) for pulling electric power cable.

Capstan Wear - Our ropes pick up dirt, grit and water. Apparently the factory-made capstans are made of an alloy that is fairly robust. The ropes generally just polish the drums.

Ropes - Back in the day, we used triple braided ropes. We recently tested some Amsteel Blue and only some of the guys liked it. There were some complaints that it slipped too much on the capstans due to the smaller diameter of the rope in a given rating. To go with a rope with twice the diameter for the same pull increases the contact area of the rope / capstan for better traction is my guess.

Very low stretch polyester is what we normally use. I once pulled a long cable run (4-500MCM & Ground) with Greenlee braided rope where we needed to change the setup with about 300 feet remaining to be pulled. When we stopped and eased up on the rope, it went about 15-20 feet back into the conduit before stopping. I'm not sure Greenlee even sells this type of rope in the larger diameters any more.

In our application, most of the energy released in a rope failure would either be contained in the conduit and the cabinet we are pulling into, or shoot straight out of the end of the conduit. Using the winch in the open increases the area of exposure to flying things. If a chain would decide to ride the stretched rope back to your tractor it could get ugly.

Number of Wraps - In general, we have anywhere from 2 to 4 wraps on a capstan. The capstan diameter, load, rope and amount of finesse the operator has determine that. All of our ropes slip some on the capstans. Someone with good mechanical aptitude can quickly figure out how many wraps they need to do the pull without excess slippage while limiting the manual force they need to use pulling the rope.

Somewhere I saw a guy pulling logs who used some kind of cone on the end of the log so it skipped over small obstructions. When choked as in your video, it looks like logs like to go chain up. That would seem to make the nose of the log into the dirt (and roots and rocks).

 

[Baby Grand]

Very interesting build - thanks for posting!
I had been thinking about building a capstan winch, myself, but ended up buying a Fransgard. I had work that needed to be done and very limited time to do it. I think the winch paid for itself in a few months, vs hiring the work out. But I put a premium on DIY, so congrats on going that route.
A couple of thoughts on what I had been thinking, in terms of my own design:

I had settled on 5/8 double braid polyester for low stretch, UV resistance, water & dirt tolerance vs cost.

A larger capstan diameter produces less bending stress in the rope - so your rope will last longer and have a greater effective working strength when you use it.

As you have observed, some type of deadman mechanism is required for even moderately safe operation. My plan was to use an auto differential to get a 4:1 reduction ratio and the wonders of differential gearing. By attaching the capstan to one output shaft and a manually operated clutch to the other, I'd get the deadman function plus a way to slip the capstan if the line got fouled and the capstan failed to slip the rope when required.

Again, kudos for a great build - keep tweaking your design until to get that desired deadman feature. Work safe and keep the updates coming.
-Jim

 

[SpringHollow]

The portablewinch site sells the cones. I have one and they work real well. Having said that, I only use it when I am pulling lots of logs. The portable winch has sufficient power that the cone is not necessary. In my opinion, the major reason to use the cone is to protect other trees etc. I have found their rope and accessories to be reasonably priced and very useful.

Ken

 

[bcp]

As you have observed, some type of deadman mechanism is required for even moderately safe operation. My plan was to use an auto differential to get a 4:1 reduction ratio and the wonders of differential gearing. By attaching the capstan to one output shaft and a manually operated clutch to the other, I'd get the deadman function plus a way to slip the capstan if the line got fouled and the capstan failed to slip the rope when required.

Wouldn't 4:1 with differential action change to 2:1 when only one side was turning?

Bruce

 

[J Man]

Wouldn't 4:1 with differential action change to 2:1 when only one side was turning?

Bruce

What do you folks think about using a old Braden or Ramsey pto winch and adapting it to be used as a capstan style rope winch. Everything would be there, just would have to install some rope guides and etc. ??

 

[J Man]

Wouldn't 4:1 with differential action change to 2:1 when only one side was turning?

Bruce

What do you folks think about using a old Braden or Ramsey pto winch and adapting it to be used as a capstan style rope winch. Everything would be there, just would have to install some rope guides and etc. ??

 

[bcp]

The capstan winches I've seen on vehicles were worm drive like that.

Bruce

 

[J Man]

The capstan winches I've seen on vehicles were worm drive like that.

Bruce

Yes it would be a worm gear pto winch. My question is would it work as a capstan winch if you used rope and just threw a few wraps around drum and started pulling logs. Of corse it would have to have a more sophisticated guide system for the rope on and off spool. Seems like it would be inexpensive if person got the winch fairly cheap and had fabricating skills. What are your thoughts?

 

[bcp]

A regular PTO winch is supported by bearings on both ends of the drum. A capstan winch on only one end. A drive meant for a capstan may have a different bearing system to better support the capstan. The gear would need bearings on both sides to support the pull.

Maybe an adaptation of a marine capstan winch.
https://duckduckgo.com/?t=ffsb&q=marine+capstan+winch&iax=images&ia=images

Bruce

 

[czechsonofagun]

Cool project!

 

[PILOON]

Talk of needing dual bearing support for capstan winch,------- well many cars use hubs that contain dual bearings and such a hub might just be the structural basis for a DIY capstan winch.

Actually a bare rim would make for the drum if only it were a smaller diameter.
A 90 deg gear box coupled to the PTO and welded/attached to wheel hub and voila a capstan winch.
LOL, with a car rim you'd not need many wraps either to be effective.

OK, laugh as it would be clumsy looking but bet it would work just fine.

 

[J Man]

Talk of needing dual bearing support for capstan winch,------- well many cars use hubs that contain dual bearings and such a hub might just be the structural basis for a DIY capstan winch.

Actually a bare rim would make for the drum if only it were a smaller diameter.
A 90 deg gear box coupled to the PTO and welded/attached to wheel hub and voila a capstan winch.
LOL, with a car rim you'd not need many wraps either to be effective.

OK, laugh as it would be clumsy looking but bet it would work just fine.

Ok, maybe I didn稚 explain my potential project clear enough? I know the difference between a normal capstan winch and other winches. What I have access to is a old Braden cable style winch with a standard horizontal drum æ¾±earings on both ends of corse and it is PTO driven. I do not know the winches gear ratio yet. And I would like to make it into a inexpensive light duty tractor style logging winch. I know people like to stay away from pto driven cable winches for these applications for the obvious and well covered reasons. So I had the idea of using rope on the existing drum just like you would on a capstan winch so I would have control of the load just like a capstan style winch. And this would be for processing my own fire wood, no high production logging. So my main question to you folks was do you think it would work more on the lines of rope slippage and recovery speed? I realize there is potential for rope wrapping on itself 努ould have to make rope guides like a true capstan and the extra effort to feed rope around the drum. Like many people I don稚 have thousands of dollars to buy a logging winch or the demand to justify buying one. I can fabricate and have resources to make stuff so this is weæ±*e I am at.

 

[MossRoad]

I'd find out the speed of it when hooked to a PTO before you proceed. It may be fine the way it is. Or, it may be too slow. It also might be of enough value to trade for a capstan winch and avoid the hassle of building it yourself. Or at least give you some good funds towards a capstan winch.

 

[SpringHollow]

How are you going to release the pressure of the rope on the drum in a setup like that? I am not sure it is open enough to allow you to not melt/burn your rope.

Ken

 

[J Man]

How are you going to release the pressure of the rope on the drum in a setup like that? I am not sure it is open enough to allow you to not melt/burn your rope.

Ken

No different than standard capstan. Just let loose?? Like I said in previous post I would would have to install some on/off drum rope guides like a normal capstan and of corse you wouldn稚 use the full length of the drum. Just throw 3.4,5 wraps around it and go. Yes a little extra work to wrap the rope but once it痴 on there it showed be good to go.

 

[SpringHollow]

With a conventional winch, the enclosed nature of the winch might not let the rope release enough. If you customized the frame to make it larger, you would be ok.

 

[lennyzx11]

“Throwing a wrap” on or off a cathead (capstan winch) is key to using one. The end has to be open for it to work or getting a wrap crossed over a lower one will create tension that is hard to release.
I spent several years running one building cell towers with one.

I met a crew that used a rim on the pickups rear axle with the tire removed. Heard about it in the industry as not uncommon.

My stepdad had a pulpwood truck with a rear axle laid across the frame right behind the cab that was PTO driven into the differential. It was his loader/puller.

A hand brake on either side had to be locked for the opposite to work. The rims outer edges were cut down some as I recall. I was only 8-9 years old back then.

 

[Sportsman762]

Here is my two cents on using a winch as a capstan.

My experience with a capstan is helping a friend who is a well driller. He specializes in fishing, and for a pump hoist he utilizes a rig is Grandfather built in 1949. It is on an International 140 and utilizes a Ford TT rear axle that has been shortened, and two capstans put on the ends. The working rope is 1" sisal, because it holds well, and can handle some burning. When your holding a 1000lbs of pipe and tooling while setting a clamp, the rope might burn a little. Because the rig is used 6-7 days a week, the capstans are always shiny. We ALWAYS throw the rope off the capstan when not in use. This is a critical safety measure. One little bur or the old opening for the winch cable grabbing the rope, or an accidental pull and the capstan is going to be sucking in rope. I can hold a 50lb piece of pipe up in the air with two wraps on the capstan, and the rope just sitting in my hand, moving my hand will raise and lower the pipe. less than a pound of force on my end causes the capstan to put out 50 lbs on the other. A rusty capstan would suck in rope, just by laying the rope on it. It would not take much for the end of that rope to be wrapped around something that it should not, like your foot. How would you spool out rope if your cannot take it off without it tightening down on the capstan? Also since your using it in a low use situation the capstan will get rusty. This will increase the friction and cause the rope to grab the capstan. Utilizing a winch as a capstan is dangerous, you must be able to flick the rope off and change number of wraps to match job.

Use your PTO winch as a winch, it will be less dangerous than utilizing it as a capstan. Capstans are amazing machines, and the amount of control they give you is nice. However you must be safe with them, don't cross your ropes, and don't leave rope on it. Some winches have capstans on the side, this would let you have the best of both worlds. Perhaps some other method utilized as a capstan would be a safer choice.

 

[Smokeydog]

Seen line trucks with bumper winches with a capstan spool on the outside of the bumper.
Right about being open ended and polished to work properly. Also puts operator 180* from the load for better sight and control.
Just in case how are you going to stop the winch, capstan or tractor quickly?
Lack of funds to justify dangerous operations is seldom a bargain.