FlyingNut40
There is good reason these professional companies have stopped using the non-heat treated dyneema. Essentially they run out of adjustment long before the creep stops and so they have to cut and re-splice, which means starting all over again.
They have spent many years, tons of time/effort/money as well to develope the DUX and other refined dyneema blends/processes to create a usable and reliable
rigging product.
It has nothing to do with strength, its all about stretch and creep. The molecules of the polyethylene (plastic) linear chains that are made by 10's of thousands into bundles and then woven together to create "dyneema" are all out of whack when first produced.
Heating them to specific temperatures and then apply a specific known load to them while traveling over heated rollers causes these molecular chains to "smooth out" or "settle in".
Its in many ways similar to heat treatments of
steel: what you are doing is dramatically changing the molecular structure of the material to create better properties for its intended use.
This happens to non-treated dyneema over time and use from the cyclical loading/unloading of the rig and causes the dyneema to gain length, this is called: creep.
Now, there is some background from early experimentation where after setting up the finished splices, they (professional riggers) were loading the finished piece with hydraulics to twice normal
rigging loads or something- this would flush out quite a bit of the splice stretch. Although, they found did not cure the creep. It allowed them to set up a
boat and go sailing though.
The plan to use turn buckles is very convenient for tuning and taking up the splice stretch, but the problem will be that the turn buckle will bottom out over time. Running lashings, you can lash and re-lash and re-lash... But they are an entire new area for stretch/creep and slack to exist.
If your goal is to save
money by spending time (which is always a related equation). I believe you MIGHT be able to buy yourself a quality drill press (a proper mill would be best of course) and carefully set up a series of jigs to make copy cat
parts of Colligo
equipment.
I believe they use T6061 which is a heat treated hardened aluminum alloy. You can cut this on a band saw with a quality
wood band and drill it with any quality
steel cutting drill bits. Be VERY careful not to heat it. To edge your blanks you can use a high speed router with carbide
wood bits- perhaps with a wet towel to keep the part cool.
This process would be very time consuming, but I would imagine if you looked hard enough you could find some off-cuts/scraps of the proper aluminum plate. After they are finished, acid etch the aluminum and
paint them.
If you order DUX from the source importer (Northeast
Canada I believe), the
price is quite reasonable.
It is not a good idea to build a rig from un-treated dyneema- you will spend countless hours and it will not
work as it should.
Read the blogs and posts of professional riggers and
head their experience.
If you would like custom "dog bones" (the rigging eyes bolted to the mast described by Ben) to bolt aluminum discs into, I would be willing to help you by sending you DXF files to have laser cut if you send me dimensions.
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