custom trailer hitch with rotating snatch block for rear winch bumper

[res0wc18]

so guys as some of you know i am working on a rear hitch setup, since i successfully installed my hidden winch. Well what i want to do is mount a hitch with something like this built into it so the winch in-line so it can swivel about each direction and drag or pull something in 180 degrees of the bumper. here is the particular thing im talking about FX Skidding Winch Features - Snatchblock Pulley System - Wallenstein

http://embmfg.com/images/products/winches/FX120_Studio_Shot_Large.jpg

That snatch block pulley system is basically what i want to do plus have my receiver mount to hook up a trailer to. Any one know where to buy something like this or have any ideas? I can build everything else except i need to no where to buy the block and pulley?

My winch is hidden behind the bumper and the fair lead is mount right about the receiver mount. I want to be able use the winch and receiver hitch at the same time.

Hope this makes sense...Thanks

 

[oldstuff]

Looks like a good Idea.
I would try for a pulley size that is about the same as the winch drum. If you go too small you risk damaging the cable by sharp bending over a small pulley.
Another thing to consider is that your snatchblock is probably going to be pretty close to the winch. This will result in the cable wanting to rewind in the same spot on the drum, possibly causing a big lump of cable in one spot. Something to think about.
Ray

 

[greenjeepster]

Benz made a Unimog just for skidding logs. It might be a good place to get some ideas for your projects. I have only ever seen one in real life, but there must be others out there.

 

[frodobaggins]

since i successfully installed my hidden winch.

Link ? Can't find it.

 

[steelandcanvas]

Link ? Can't find it.

Must be hidden in there with the winch somewhere.

 

[res0wc18]

"Link ? Can't find it."

"Must be hidden in there with the winch somewhere" ajahahah yeah i have been avoiding the post because i know im going to get on the computer too much if i do!

heres a teaser... blasted and powder coated, and i know its not flat or od paint but my truck is a little different..

 

[res0wc18]

here is another one. What do you guys think of the pivoting head idea. here is a company that makes para gliding swivel heads scroll down in the pdf and it will explain it.. http://towmeup.com/TowMeUp-winch.pdf

 

[rmgill]

You want to be able to drag/tow logs off the back of the truck with the fairleads taking more of the weight right?

Have you looked at how some of the British Artillery Tractors did this? They'd have a mid ship winch under the bed and the drum would be vertical. It would feed forwards OR to the rear of the truck with fairlead pulleys on both ends.

I did some quick searches and can't find a good detail photo. Let me look later and see what I can find. The way the recovery trucks AND the artillery tractors do it would be about right though. you'll want bigger fairleads for tight pulls to the side on the big cable.

 

[Beerslayer]

Agree that bigger fairleads will save the cable. They are pretty easy to build yourself. All you need is some heavy pipe, get someone to turn down some nylon bushing to go in the ends of the pipe, and some plate to make mounting ears with.

 

[rmgill]

You really want a pulley that'll swivel with the angle of the pull though. With our winches a 6" sheave is desirable and a 6" diameter fairlead is going to be pretty darn chunky. And the Pulley block's mount will have to be able to handle the loads you expect to be redirecting, potentially up to the weight of the pull I'd think.

 

[res0wc18]

yeah the pulley block mount/towing receiver would have to hold the weight plus another good deal for the stress of the angles. Im ging to try and draw up some plans of what i need. Essentially what i want to be able to do is have the trailer reciever hook up so i can have the trailer or what ever im pulling hooked up, and then have the pulley system slightly above that so i can pull what ever i want up on to the trailer for example, or if i have the trailer unhooked pull something at any angle(within limits of course) to the truck putting less strain on the winch etc. I got the bumper etc all done and installed this weekend.

 

[res0wc18]

here is another

 

[rmgill]

The problem is that you want to pull at 90 degrees from the rear right? If you do that, with those fairlead rollers acting as the pulleys, you're going to very quickly ruin your winch cable. Based on the size of our cables, we need about a 6" sheave for anything but basic guide rolling. a Sharp angle around one of those rollers is going to be VERY bad for the winch cable.

The Coast Guard's rule of thumb is that the diameter of the sheave should not be less than 20 times the diameter of the wire rope. For 1/2" wire rope a 4.5 " diameter sheave is the min size. A 6" sheave as we have on our usual snatch blocks is less stress on the wire rope and better in the long term.

Here's an idea for a rotating fairlead that might work for you.

 

[res0wc18]

The problem is that you want to pull at 90 degrees from the rear right?

exactly. i want to be able to pull to the extreme right and left of the center of the bumper. I will have the swivel pulley sticking about 8 inches or so from the roller fairlead.

I can build whatever size swivel roller(what the heck are those things called anyway?) i want into it. I figured 6" or so. Where can you buy one? Or am i going to have to build my own?

 

[rmgill]

It's an unusual application. You might have to go with a custom fabrication. Start with a winch snatchblock for the sheave/pulley. Build your side plates and then start trying to figure out how to mount the swiveling part. Perhaps a tubular section mounted to another tube with a flange (sort of like the Pintle hook's swivel and with a greasable bearing. It's not going to want to pull out, it just needs to pivot.

 

[rmgill]

Ok, I just had an inspiration. You'll have to do some welding but I think this could work.

YOu'll need a scrapped deuce axle tube and wheel hub. Oh and a Snatchblock. Plus a bunch of thick metal.

The wheel hub becomes your base. The axle tube is your pivoting center for the sheave to mount to. The axle nut goes on the inside. Here's a quick and dirty drawing...

 

[rmgill]

a bit more thought out...still not really to scale though.


Oh, key detail, the centerline and cable position is SLIGHTLY off so as to bias the sheave to swivel to the 'low' point when pulling at anything but right off center.

I suppose you could add a couple of rollers to this along the other paths of the cable to prevent any wearing of the mount.

 

[clinto]

Nice drawings, Ryan.

 

[rmgill]

Ok, final version with some tweaks and annotations.

Hey Clinto, any chance we can post VSD file formats?

 

[res0wc18]

not bad my friend, not bad at all. I dont have an extra deuce tube and hub though...

I cant see or read the drawing very well its so small, how can i download it in full size etc?