How to use Ropes & Knots to build a log cabin by hand

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Up close cradle on triple blocks (bottom block is homemade).

I’ve always been intrigued with rope and string, and the many uses for it. A few years ago, I even took up knitting, and I’ve come up with my own designs for socks, sweaters, hats and scarfs. The idea that clothing can be made simply by looping string together is quite astounding when you think about it. And building a cabin with ropes and pulleys is a fascinating step back in time. Some of the pulleys I used were 100 year old antiques I found on Ebay. But I made others myself.  Now that I’m all but done using ropes, I feel I should document the various knots and holds I utilized to help build the house. As a former Boy Scout and as an outdoor enthusiast, I already knew most of the knots I would use. And yes, I can tie a sheep-shank. But there are some new ones I had never used.

Out there in internet land, there are many “how to” articles. Most are written as puff pieces by folks who have never actually used the ideas they are promoting, mainly just writing for clicks for advertising. Rest assured that I have used every knot and method below, and everything works just as I describe. These are all the knots you will need to build a cabin using block and tackle.

The rope

I’m using 5/8″ triple ply dock rope (poly rope) available on Ebay for about $130 for a 600 foot roll.  I’ve used about 1500 feet of rope so far (3 rolls). It has a working load of about 700 pounds, and a breaking strength of about 4,000 pounds.

NOTE: LHBA now recommends using double-braided rope if building with lifting poles and block and tackle, due to its increased strength, compared to the same diameter of triple-ply rope. But I decided against double-braided rope for two reasons:

1. Cost: double braided rope is much more expensive.

2. Ease of repair: Triple ply poly rope is easy to splice. Double-braided rope cannot be easily spliced. This means you must buy it in the length you need for use- for me, it would have been 220 feet each. If it breaks, you must buy another 220′ length. This seemed impractical for my build, and I decided to take my chances with the somewhat weaker triple-ply poly rope.

Why so long on the rope? If using triple blocks, the rope will pass through the blocks seven times. 7 * 30′ (lifting poles) = 210′, plus enough to tie onto your tractor.

Various manufacturers will give different load calculations, so check when you’re buying. The 5/8″ rope I used said it was rated for 700 lbs of load, and had a 4,000 lb breaking strength. The lower number is the one you don’t want to exceed. The upper number applies to the force (mass x acceleration): as in when a log begins to fall and the rope suddenly stops it. Finally, I found a helpful method to loosen a knot I can’t untie: I hit it with a hammer while turning it over and over.

Now that I am finished with the part of the build that requires a lot of rope, I can say the triple-ply rope held up almost perfectly. I never had a triple ply rope break when it was used properly. Note that I built the largest cabin designed by LHBA: the 40×40, using logs that average 17″ diameter, and weigh up to 6,000 lbs.

Safety

I did have several close calls where the rope broke, but these breaks were always due to the rope being bound up in one of my antique pulleys, and then getting sliced by one of the pulley faces. And these close calls luckily always happened when the log was only a few feet off the ground. I always keep children and dogs away from whatever I’m lifting. Also, never allow anyone in the line of sight of a stretched out rope- if that thing were to snap, it’ll act like a whip and could take out an eye or worse.

My rules are pretty simple- don’t ever put a part of your body you’d like to keep under a log you are holding with rope- this means don’t walk under a log, don’t stick your hand in between two logs to get a tool, be aware of the location of everyone on site while you’re working. Warn everyone you’re about to lift, make sure they acknowledge you, stay clear, etc., and on and on. Check and double check what you are about to do. Know what it will look like when it is finished before you start lifting.

And now, onto the….

Knots

Note: The links for each knot take you to a video I made on how to tie that knot.

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sheet bend

Sheet Bend: Don’t use a square knot that can jiggle loose or become impossible to undo when you can use a sheet bend. This is a great way to tie two ropes together, and comes apart when you’re done. I’ve used this one recently when removing a motor and transmission from a car using a length of seatbelt scrap. And if you loop the last end instead of pulling it tight, you can untie it even more easily. Not that it’s difficult to untie in the first place, but….

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figure 8 knot

Figure 8 knot: don’t use an overhand knot when a figure 8 knot is better. I use this one when I need to take up some space in the rope (like to make sure the rope doesn’t get pulled through a hole), or when I need to shorten the strap around the log. They tend to be easier to untie than an overhand knot when you’re finished using them.

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bowline

Bowline: This knot creates a loop that will never get too tight, and also can hold people and tools. It can also be tied using one hand.

 

Holds

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prusik knot

Prusik Knot: This was a game changer- it suspends the log so you can move the tractor to a better position. Doesn’t look like it will hold because of the thin rope, but it does- along with the triple blocks, I’ve dangled 6,000 lb logs in the air with this knot.

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tent hitch or tautline hitch

Taut line or tent hitch: I use this on my safety line to keep it tight. Sometimes the lifting poles shift when a heavy log is attached, so this knot is nice and easy to re-tighten, or loosen so the rope can be re-positioned.

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double half hitch

Double Half Hitch: I use this knot to tie the rope to the tractor. Easy to tie, easy to untie- never gets too tight.

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telephone lineman hitch

Telephone lineman cable hitch: Ok, I don’t know what the real name of this hitch is. But this is what I call it. I used to use it at the phone company for pulling cable through a conduit. As long as you keep tension on it, it will hold. As soon as the tension is released, it will fall apart. The secret is making sure you throw the loops on the piece correctly. It works for pulling 20 foot- 2×10’s up onto a 25′ roof, too.

Loops

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You can turn this log to the right or the left, depending on how you loop it. When the rope is pulled on this log, it will turn towards the left.

Sometimes you need to turn the log up in the air. Depending on how you hook up the strap, you can force the log to turn whichever way you need. The trick is to pass the free end of the strap through the loop in the end of the strap such that when the strap is tight, friction forces some rotation at the connecting point. I used lots of 6,000 lb 6′ loop straps available from Harbor Freight. Four on the top of the lifting poles, and four at the bottom  of the pulley.

Also, don’t forget the quick release pins I used when installing the rafters. See this video. This makes it possible to release the lifting straps from the safety of the ground when using a crane to install rafters. Sure beats shimmying out onto a rafter 25 feet off the ground to loosen a strap.

Splicing Rope

Unfortunately, rope wears out or frays and becomes dangerous. You can splice two ropes together using a “long splice” and almost maintain the original integrity and strength of the rope. I’ve never had a long splice fail, even with logs that weigh thousands of pounds. Here’s how to splice rope in a way that keeps the integrity of the rope, and yet will still pass through a pulley. For use with 3-ply rope.  This method connects two pieces of rope using 3 splices, and each splice contains 2 “sub-splices” using 1/3 of each strand. The best video for it is also the most boring one:

Long splice

 

That’s it for knots. If you have one you like, let me know!

 

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mudflap

Just a regular guy from Utah, now living in Alabama, involved in life, liberty, and the pursuit of happiness.

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