Ultralight Block and Tackle (a neat product and a DIY Hack)

[JAG]

I listened to a recent podcast that mentioned the PynchPulley from Wiser Precision. These ultralight pulleys are very nice. With them, you can lift a lot of weight with a fraction of the effort.

I almost pulled the trigger and thought, what about a motorbike chain as an alternative, DIY hack? Here are my two set-ups, one with 4:1 and the other with 6:1 (the other half of the 6:1 pulleys were in the garage). I tack-welded the 4:1 pulleys to keep them straight, but I don't think this is really necessary.



I researched the breaking strength of a single link of 410 motorbike chain, but all I could find was statistics for the entire chain. To the garage. I stressed the cord with two clamps to test the strength of the chain link and could not get enough weight to break the cord or a single link. This would be helpful to lift an elk up a short cliff or out from underneath a log.



6:1 pulley mechanical advantage: for every 1 pound of force applied, you can lift 6 pounds of weight. With a 700-pound load (entire elk), you would need to apply approximately 116.67 pounds. My 6:1 pulley system is going in my kill kit in case I have an elk under a log or down a short cliff.

A 4:1 pulley mechanical advantage; with a 200-pound load (bone-in quarters and backstraps), you would only need to apply 50 pounds.

I have 2mm Dyneema (440 pound tensile strength) and 550 paracord (550 lb tensile strength). For the attachment points of the load, I doubled the Dyneema for 880 tensile strength, but the weight on each of the pulley's will be considerably lower than 440 pounds each.

 

[elkduds]

 

[JAG]

This is a much easier-to-make solution than the chain, but doesn’t have the benefit of the reduced friction that the rollers offer.

It’s good to see how the chain links are smooth enough to work.

 

[elkduds]

This is a much easier-to-make solution than the chain, but doesn’t have the benefit of the reduced friction that the rollers offer.

It’s good to see how the chain links are smooth enough to work.

It is small, light and good for hoisting deer-sized game, elk quarters, nothing heavier. I carry one in a ziploc. Not as robust as yours, though.

 

[Rogerdoger]

I just was looking at these, I like the idea of the dirt bike chain, save me some cash!

 

[Syoungs]

I like the bike chain idea.
Ill probably end up just getting the pack a pull system with some dyneema rope as its easy, But i may play with the chain idea to make some for my buddies, or redundant systems!

 

[JAG]

This is a cry-once-buy-once aspect of the project.

100' of 550 paracord (4mm diameter) does the job for around $12. However, it really starts to stretch and lose efficiency. In my nonscientific test with the two clamps and short orange paracord (photo above), it stretched at least 2 inches before I couldn't crank it anymore. This is a lot of stretch from about 3' of paracord and efficiency loss if pulling 20-50' of cord. Some of it was the knots tightening, but like I said- 'non-scientific'.

I won't use the 2mm Dyneema (green cord in the photo) as a pull cord through the pulleys for two reasons, 1) it's expensive and 2) it looks just small enough that heavy weight could get it pinched in between the roller/bushing connection to the inner plate.

If you want next-level performance with nearly zero stretch and superior tensile strength, get 3.5mm or 4mm thick Dyneema. One site has a 100' roll of 3.5mm Dyneema for $54.

Other items: $14 for 410 motorbike chain (has a bushing, roller, and a pin for low friction)
Angle Grinder: $25-$75 on Amazon to cut the chain plates and round over the burrs.

 

[Bluffgruff]

Viadana pulleys and 5/32" dyneema.

1000lb working load limit.

Learn to splice dyneema because knots aren't as good because of how slippery it is.

Realistically pick up 3x your body weight with a 4:1 system.

 

[elevatorman]

I made myself a set out of small flat bar, a 1/4" grade 8 bolt, and ball bearing pulleys that are cheap and easily found at lowes or home depot (meant for sliding rear glass doors). Perfect size for paracord. They're designed to hoist a deer to be able to butcher it and pack out the meat if deep in national forest, while being small and light to fit in my pack. I'll be darned if I'm dragging a deer for miles.

 

[Rogerdoger]

I listened to a recent podcast that mentioned the PynchPulley from Wiser Precision. These ultralight pulleys are very nice. With them, you can lift a lot of weight with a fraction of the effort.

I almost pulled the trigger and thought, what about a motorbike chain as an alternative, DIY hack? Here are my two set-ups, one with 4:1 and the other with 6:1 (the other half of the 6:1 pulleys were in the garage). I tack-welded the 4:1 pulleys to keep them straight, but I don't think this is really necessary.

View attachment 361240

I researched the breaking strength of a single link of 410 motorbike chain, but all I could find was statistics for the entire chain. To the garage. I stressed the cord with two clamps to test the strength of the chain link and could not get enough weight to break the cord or a single link. This would be helpful to lift an elk up a short cliff or out from underneath a log.

View attachment 361242

6:1 pulley mechanical advantage: for every 1 pound of force applied, you can lift 6 pounds of weight. With a 700-pound load (entire elk), you would need to apply approximately 116.67 pounds. My 6:1 pulley system is going in my kill kit in case I have an elk under a log or down a short cliff.

A 4:1 pulley mechanical advantage; with a 200-pound load (bone-in quarters and backstraps), you would only need to apply 50 pounds.

I have 2mm Dyneema (440 pound tensile strength) and 550 paracord (550 lb tensile strength). For the attachment points of the load, I doubled the Dyneema for 880 tensile strength, but the weight on each of the pulley's will be considerably lower than 440 pounds each.

Did you have a chance to use this setup out in the field? Was going to make this setup, ended up buying some #40 roller links and added bushing. Was easy to manipulate as it has pin you can remove but it is too wide and gets off center with weight.

 

[JAG]

Did you have a chance to use this setup out in the field? Was going to make this setup, ended up buying some #40 roller links and added bushing. Was easy to manipulate as it has pin you can remove but it is too wide and gets off center with weight.

In the field, yes. On game, no.

I used our 4:1 pulley for our camp's food bag. It was easily 150# (maybe 215#) after combining food and unused camp gear in two (2) very full llama panniers. Yes, heavy. After budgeting Llama costs, I went cheap on food (i.e., shelf-stable, block cheese, summer sausage, flour, oil, bottled water). The bottled water trick helps even out pannier weights quickly and practically.

For reference, none of us could use our body weight to pull-slide the load over a smooth branch. Yes, we wrapped the cord around a stick, so hurting our hands wasn't a factor; just weight and friction.

With the pulley, it was easy to hoist. Then, I let my 12-yo son pull it the rest of the way.

I bought two sets of three chain links, but haven't tried them yet. I plan to compare it with the roller chain, unless you beat me to it. If hoist performance isn't significantly better with the roller-chain, I'll select the chain-link option. Chain link weighs less and has fewer moving parts.

Weight savings returned to importance for me since I won't use Llamas unless I've hunted the area I'm going to.

 

[JAG]

Viadana pulleys and 5/32" dyneema.

1000lb working load limit.

Learn to splice dyneema because knots aren't as good because of how slippery it is.

Realistically pick up 3x your body weight with a 4:1 system.

View attachment 362047View attachment 362048View attachment 362049

This post reminds me of another test I did and forgot about. Ensure you use a climbing carabiner. Mine looked similar to the one pictured. They came with these velcro strap holders from HomeDepot, labeled "not for climbing", but I still thought it would suffice. Anyway, mine busted under weight while using the roller-chain hoist.

I like this pulley system, but I'm aiming for a smaller and lighter set-up with thinner rope (4mm paracord or 2mm Dyneema).

My fantasy is to get a bull down 6 miles in the wilderness, fasten a log in between two trees, and hoist it up as they do in deer camp.

The PynchPulley may be the best 'buy-once, cry-once' option. I'm a tinkerer and knew when I started down this road, my time would (and it did) outweigh the cost of the PynchPulley.

 

[Dsnow9]

This post reminds me of another test I did and forgot about. Ensure you use a climbing carabiner. Mine looked similar to the one pictured. They came with these velcro strap holders from HomeDepot, labeled "not for climbing", but I still thought it would suffice. Anyway, mine busted under weight while using the roller-chain hoist.

I like this pulley system, but I'm aiming for a smaller and lighter set-up with thinner rope (4mm paracord or 2mm Dyneema).

My fantasy is to get a bull down 6 miles in the wilderness, fasten a log in between two trees, and hoist it up as they do in deer camp.

The PynchPulley may be the best 'buy-once, cry-once' option. I'm a tinkerer and knew when I started down this road, my time would (and it did) outweigh the cost of the PynchPulley.

Dmm xsre. Thank me later

 

[Caseknife]

Built the motorcycle chain set-up, didn't work so smooth for me. Think I will order a couple of the Wiser pulleys.

 

[Bluffgruff]

This post reminds me of another test I did and forgot about. Ensure you use a climbing carabiner. Mine looked similar to the one pictured. They came with these velcro strap holders from HomeDepot, labeled "not for climbing", but I still thought it would suffice. Anyway, mine busted under weight while using the roller-chain hoist.

I like this pulley system, but I'm aiming for a smaller and lighter set-up with thinner rope (4mm paracord or 2mm Dyneema).

I regrettably took this picture with a non-climbing clip instead of the black diamond 24kN climbing carabiners that I use with it. Also, this is 4mm dyneema, for the big bulls.

LiteWire Carabiner

The Carabiner is featuring a hot-forged construction—allowing us to remove weight where it’s not needed and add material where durability is key— and a hinge-basket that holds the sling of a Camalot adds durability not only for the carabiner, but for your rope as well, plus we’ve optimized the...

blackdiamondequipment.com

 

[Dsnow9]

I regrettably took this picture with a non-climbing clip instead of the black diamond 24kN climbing carabiners that I use with it. Also, this is 4mm dyneema, for the big bulls.

LiteWire Carabiner

The Carabiner is featuring a hot-forged construction—allowing us to remove weight where it’s not needed and add material where durability is key— and a hinge-basket that holds the sling of a Camalot adds durability not only for the carabiner, but for your rope as well, plus we’ve optimized the...

blackdiamondequipment.com

“Big bulls” I see what you did there! Just because I don’t shoot them doesn’t mean my setup wouldn’t lift a big bull. Maybe some day I can prove myself as a real hunter!