Friday, April 23, 2010

Hose suspenders - Part 3

The other major component of a hose suspender is a loop of rope which is wrapped around the hose (lark's head method if you're interested) prior to hooking the hose suspender on one of the ladder rounds.
I obtained several metres of 15mm polypropylene rope for this project and did consider splicing the rope, but came up with another method which reduced the bulk, and rigidity of the rope.
I was concerned that if I spliced the rope into a loop, I'd effectively double the cross-section of the rope at the splice, and thereby reduce it's flexibility.
I decided a better way would be to use the method of splicing used for making "quoits". This method does not change the cross section of the rope, and therefore doesn't change the flexibility.
To make a quoit, you determine the diameter of the loop, and then roll out three and one half turns of that diameter - see photo below.
You then separate the three strands of the rope, and using only one strand, reform the loop. You will find a point in the loop where the strand "sits" nicely into the twist of itself. I looped the strand through the eye of the hook as part of the first loop, and commenced the twist as shown below...

You basically reform the twist of the original rope by threading it around itself as you move around the loop. The strand will settle back into it's original twist, and forms up nicely as if never unwound. The picture below shows the second turn coming around, and commencing the third turn.


As seen above, where the three turns have been made, the rope looks normal, full diameter, and no unusual lumps or bumps.
Once three full turns are made, you have to join the strand to itself. For a quoit, you'd normally do something a bit fancy, but for these hose suspenders I simply took a heated knife blade, and cut the two strands so they overlapped by 3mm (1/8"). I then heated the knife blade again, and placed it between the two ends so they both heated, and then withdrew the blade so they came together and fused cold as one strand.

I have a collection of "garage sale" utensils which are used for this sort of abuse - there's no way I'd survive sticking one of our kitchen utensils in the flame of a butane torch - quite simply, "the Boss" will string me up.

The hose suspender weren't the only things done... I also made up three suction line ropes (15M) long, 56 lanyards for salvage sheets (1.8M long), and the 9 hose suspenders.

Lessons learned? don't cold forge 3/8" rod without strong tooling, and if necessary, use cuts to weaken the rod for tight bends... also, don't put "the paint is dry" hose suspenders on the kitchen table to splice the loops unless the paint has had at least 2 months to dry... 48 hours is not enough with thick paint, and for some reason what doesn't come off on your hands, will come off on the table cloth - sorry dear.

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