Mechanical Advantage Advice

B

B_Strange

Participating member
Location
Simmonsville
Howdy folks. My uncle wants me to clean up a fence line on his farm and is willing to pay for gear to get the job done as well as pay me for my time. Kinda cool of him to do that. I don’t want to waste his money so thought I’d tap the hive mind as to MA kits. Any you like? Any you hate? Buy components and build my own? This would be used to pull over spars. Not huge ones. I have a porty and 200’ of 1/2” Hawkeye.

I put hands on the AZTEK kit at Expo at RE double sheaved Omni blocks and love em but don’t want my uncle to pay for sexy gear if another prussic minding pulley will do the job.

Thanks!
 
I wish I would’ve sprung for at least 1 double Omniblock 1.5” or 2” . I still might. A swivel at the anchor is nice.
The Aztec kit looks nice, but less cost you can have a pair of double pulleys that will take 1/2” rope that you already have. The Aztecs take 8mm or something like that?
 
I hear you! The AZTEC looks awesome but the small diameter of the cordage is what gave me pause. Thanks for your thoughts. I agree about buying pulleys to work with what I have.

What do you use for a 5:1 MA if you don’t mind me asking?
 
A double prusik minding pulley 2” sheave and a double mini machined bearing pulley both from RE. Also a pair of aluminum CMI rescue pulleys for 3:1 which is often more than enough.
I got a Petzl open swivel I’m gonna put on the PMP.
A6A4378A-F47A-4DBB-8176-CCB1E29885CE.webp
 
Get a couple Gryo Twins from DMM, a decent hi-temp hitch cord. (You will need a e to e an a loop, ( I like Sterling 10mm RIT)) a good rigging line and appropriate connecting links (with the gryos they do not need to be hardware) and never look back.

Gyro Twin | Pulleys | DMM Wales

Browse Gyro Twin products in Pulleys. Available to buy online, delivered direct from DMM Wales.
dmmclimbing.com dmmclimbing.com

Tony
 
Tony said:
Get a couple Gryo Twins from DMM, a decent hi-temp hitch cord. (You will need a e to e an a loop, ( I like Sterling 10mm RIT)) a good rigging line and appropriate connecting links (with the gryos they do not need to be hardware) and never look back.

Gyro Twin | Pulleys | DMM Wales

Browse Gyro Twin products in Pulleys. Available to buy online, delivered direct from DMM Wales.
dmmclimbing.com dmmclimbing.com

Tony
Click to expand...
Thanks Tony! I like the way those pulleys look. I’m going to give my uncle a call and see what he was thinking budget wise for gear and go from there. Thanks
 

As always, use wedges.
Easy to redirect with a strong enough pulley to get back to the cutter if you're rolling solo.

Looks to be basically like the Maasdam Continuous Rope Puller, with a built-in 2:1 option.


Never seen it before, fwiw.



From looking at the sheave radius and lever length, I think a Maasdam is about 7:1 MA with progress capture.

Follow the directions...make sure the pawls are always seated...easy to do. Pull steadily, not herky-jerky.


I have a 4:1/ 5:1, GRCS, and mini. The rope puller is still very useful, lightweight, super fast and easy to set up. I often just use the pull rope as my puller's anchor rope, after feeding through the device, I'll anchor with a RB, then girth-hitch the anchor hook or use a bowline on a bight (or is it Bowline with a bight??).
 
southsoundtree said:

As always, use wedges.
Easy to redirect with a strong enough pulley to get back to the cutter if you're rolling solo.

Looks to be basically like the Maasdam Continuous Rope Puller, with a built-in 2:1 option.


Never seen it before, fwiw.



From looking at the sheave radius and lever length, I think a Maasdam is about 7:1 MA with progress capture.

Follow the directions...make sure the pawls are always seated...easy to do. Pull steadily, not herky-jerky.


I have a 4:1/ 5:1, GRCS, and mini. The rope puller is still very useful, lightweight, super fast and easy to set up. I often just use the pull rope as my puller's anchor rope, after feeding through the device, I'll anchor with a RB, then girth-hitch the anchor hook or use a bowline on a bight (or is it Bowline with a bight??).
Click to expand...
Thanks for the advice! I appreciate it. Just starting out so trying to be super careful with money gear wise. Wedges will definitely come into play for sure. I figure a pull line and MA are cheap insurance as I get more experience in felling.
 
You can add security against rope sliding back in the sheave by tying an overhand-on-a-bight every couple feet. The right friction hitch would probably tend itself against the fairlead-eye, attached to the anchor sling.

Bowline-with-a bight https://www.netknots.com/rope_knots/bowline-on-a-bight would allow one loop for the puller hook, one loop for a carabiner or snap-hook attached to the friction hitch as your back-up.







You need to get enough tension on the line before the sheave will grip effectively.





Bang for the buck is favorable.
 
The Aztek kits are great for the rescue world but not so much for the ARB work. My 5:1 setup is two CMC double pulleys, a quick link, a prussic, two carabiners and a retired climbing line. It's probably the cheapest way to go for a good block and tackle and you probably already have some of the gear. Just keep in mind most double pulleys are designed only to have both sheaves loaded, not for single use. Bit of a one trick pony.

I've never used the maasdam but I've heard really good things.
 
southsoundtree said:

As always, use wedges.
Easy to redirect with a strong enough pulley to get back to the cutter if you're rolling solo.

Looks to be basically like the Maasdam Continuous Rope Puller, with a built-in 2:1 option.


Never seen it before, fwiw.



From looking at the sheave radius and lever length, I think a Maasdam is about 7:1 MA with progress capture.

Follow the directions...make sure the pawls are always seated...easy to do. Pull steadily, not herky-jerky.


I have a 4:1/ 5:1, GRCS, and mini. The rope puller is still very useful, lightweight, super fast and easy to set up. I often just use the pull rope as my puller's anchor rope, after feeding through the device, I'll anchor with a RB, then girth-hitch the anchor hook or use a bowline on a bight (or is it Bowline with a bight??).
Click to expand...
2,000 lbs will with a 10mm line..
 
Lotta power of about 7:1 piggybacked on 3:1 or 5:1.


I've never tried to pull a tree with the Maasdam CRP that was too much. The hardest pull was probably skidding big walnut logs, straight, not piggybacked.
 
SeanRuel said:
Anyone piggybacked a rope puller and pulley system? Rig 5:1 with tail going into puller?
Click to expand...

Yes a couple times, it works well and makes for some big force. Sometimes when something is leaning far enough to warrant that kind of pull, there’s also problem with the center of gravity shifting a bit to one of the sides while pulling towards the anchor.

So if the tree is straight and just leaning hard or has weight on the backside away from the anchor, it could be a good method to add MA on more MA. But if there’s weight or lean off to a side of intended lay as well, you may have to leave the hinge really thick on the tension side and/or set another rope to work like a guy line to try to counter that lateral lean, then have another worker sweating out slack and keeping tension to counter that lateral weight/lean as it’s starting to come over.
Depending on the health, species, and the characteristics and condition of a trees hinge wood, it’s out of the question sometimes.
I might consider it on some sound silver maples or blue spruce or anything that holds a hinge pretty well but probably not on tree of heaven or dead cottonwood or most trees that are decayed.

Sorry if I’m not explaining well or if that should all go without saying.
The maasdam moves rope a lot slower than a person can pulling by hand, and sometimes you need to move that canopy many feet before the tree will start to fall.
Also it’s not hard to break smallish tops out with a 5:1 + maasdam.
 
SeanRuel said:
Anyone piggybacked a rope puller and pulley system? Rig 5:1 with tail going into puller?
Click to expand...

If a pickup counts as a rope puller, then yes. :LOL:

Not often but I have pulled a 4:1 with a truck.

When a MA system needs to be built I use my regular rigging ropes and blocks and build what I need at the time.
 
You must log in or register to reply here.

New threads New posts

Kask Stihl NORTHEASTERN Arborists Wesspur TreeStuff.com Teufelberger Westminster X-Rigging Teufelberger
Back
Top Bottom