Double Whip Tackle

[lumberjack]

Haha a low stretch rope is amazing for lifting with the grcs. It's also hard to get the drum to grab 3/4" rope on heavy lifts. 9/16" is about the limit on the original capstan for heavy lifts without someone on the tail.

 

[sotc]

I guess i'm not following now. The attachments points will see larger loads than the line in the tackle will...

 

[gf beranek]

Alright,, the ol' MA debate comes to life once again.

 

[emr]

Is it a similar issue to the oil mix and veggie bar oil debates? If so, you I am sorry. I didn't mean to stir the pot.

 

[Burnham]

I guess i'm not following now. The attachments points will see larger loads than the line in the tackle will...

Absolutely, Willie.

 

[lumberjack]

Holy moly, where's all the confusion coming from? I thought this was super simple stuff.

 

[Burnham]

We have to consider that it's Willie claiming confusion .

 

[lumberjack]

Triple Whip Tackle.

<iframe width="420" height="315" src="http://www.youtube.com/embed/43uW4jFN7SI" frameborder="0" allowfullscreen></iframe>

 

[sotc]

We have to consider that it's Willie claiming confusion .

Normal..

 

[Al Smith]

FWIW it's not exactly 2 to 1 when using multiple sheaves because there is the friction and rope bending forces around the pulleys .For purposes of debate though it's close enough .

The tie point and the anchor point will have the same force wheras the pull point will be reduced by whatever mechaincal advantage afforded by the rigging passes through the multiple blocks .If you had enough blocks you could probabley move a D9 Cat with a skidloader .Of course you'd have to pull a mile to gain an inch .

 

[Al Smith]

Once upon a time like a dumbass I stuck a D4 Cat so deep in a creek the water was running over my feet and the fan was throwing water in my face ,duh .I couldn't shake it with another dozer ,just spin the tracks .My brother and I used the other dozer as an anchor point by shoving up a big pile of dirt with the blade and tying off a series of six snatch blocks ,three to each end of the pull .Strung those blocks with 1/2" wire rope ,seemed like a mile of it and tugged that water logged old dozer out with a 3/4 ton Chevy wrecker .Took a while but eventually out it came mud and all .

 

[Cobleskill]

I had a rented dozer in a wash out swirl in my creek. It generally has a pretty stony hard bottom. The tracks started spinning, bringing up sticky clay. Luckily I made it out, and stayed out.

 

[Al Smith]

Good plan .I've stuck just about anything that can get stuck and a swamped dozer is by far the worst of any of them .Oh I suppose a grounded aircraft carrier would be worse but as of yet I could never afford one .

 

[flushcut]

Who's on first?

 

[SoonerFan]

Yes he is.

 

[Jed]

Willie's confused? I never even seen or heard of this stuff before!!!

About to watch the vid though. It's a real good second-hand education through you guys. Someone shld make a training vid. entitled "Rigging for Inbreds."

 

[gf beranek]

Then you have to figure too if the MA is to advantage or dis-advantage. Ha!

 

[flushcut]

Then you have to figure too if the MA is to advantage or dis-advantage. Ha!

Well played!

 

[Al Smith]

There a topic or study of which they classify "simple machines" .Of which the lever and fulcrum ,the wheel ,inclined planes ,ropes and pulleys are among the most simple and oldest devices known to mankind .The principals of these items have never changed in all of recorded history .Only improved slightly .

 

[gf beranek]

The old watch makers skills always impressed me. Miniature machines of such precision and beautiful craftsmanship in a time of very low tech.

 

[Marc-Antoine]

Haha a low stretch rope is amazing for lifting with the grcs. It's also hard to get the drum to grab 3/4" rope on heavy lifts. 9/16" is about the limit on the original capstan for heavy lifts without someone on the tail.

Given that, what's the max load a Grcs can handle directly (lifting with no MA) ?

 

[lumberjack]

2500 lbs is the rated swl.

 

[Marc-Antoine]

Wow, dead lifting my car !
It begins to get some serious chunk.
I should put one on my wish list, but it's a lot of money for now.
Thanks.