Tuesday, February 15, 2011

Notes to self on DIY of the Megatron chicken loop for Flysurfer bars

With pictures and more or less information.

Update - ordered some Samson LashIt! twine from the US ... made from Dyneema and UV coated, 180 feet for $25 plus the same for shipping 0_o 1.75mm and 500lbs (230kg) breaking load - just what the doctor ordered! Hopefully :D and there should be much less grunting and swearing involved ...
Update on the update - LashIt! has arrived and looks excellent - adds very little to the thickness of the 5mm and oddly enough, looks exactly like what is used in the Flysurfer depower line ... will get into making a line tonight and promise to take pictures!

Supplies
• About 150cm of 5mm (3/16) Amsteel Blue SK-75, breaking load 2,500kg for the depower loop line
• and 100cm of 2.8 of Amsteel Blue SK-75, breaking load 750kg for the "core" ... probably the 2.2mm LashIt! would have been better than the 1.75mm but cest la vie and all that.
• 5/8mm ID/OD PU tubing - goes under the spinning handle and is easier than reusing the Ozone stuff ... it's just compressor line anyway
• Ozone Megatron chicken loop (duh) with the "Spinning Handle" for the 5th line safety
• Heat-shrink (or whipping line - synthetic)
• Needles and thread (synthetic too)

Tools
• Long-nosed pliers
• DIY pull fid - made from coated 20-gauge wire, put the end you want a loop in, in a drill and spun slowly till at least 1m long
• tie ball to push the tubing, about 20mm

0. Skip all this crap and use the Beal line. The easiest option by a country mile, but 1,200kg breaking load bothers me ...

1. Cut the PU tubing to fit inside the "Spinning Handle" - about 6cm long.

2. Taper the end of the 5mm Amsteel ...
• measure and mark at 70mm, 90mm and 110mm
• pull out 2 braids at each mark, starting at 110mm and working towards the tip
• should leave about 3-4 lines at the tip - if there's more, pull out a few more between the marks - keep the taper smooth!

 


3. Splice the 'core' into the 5mm Amsteel with the wire fid. Leave some sticking out on either end so you can pull it tight.

 

4. Start the lock stitch about 5mm from where you plan to cut. Slide the heat-shrink over the 5mm. Stitch out away from where you'll cut, then when you turn around to stitch back, cut and heat-shrink it then stitch back to the end and over the heat shrink.

5. Figure-8 knot in that end - that'll be going inside the CL body.

 

6. Remove the suicide-leash loop. Feed the tapered end of the 5mm up into the body of the CL, orientated so that the knot will be inside. Pull the 5mm though, smoothing it over the core. Pull hard to seat the Figure-8 stopper knot.

7. Feed the tapered end of the 5mm into the PU tube - twist and push!

 

8. If all goes well, the gods are smiling, the planets align and you hold your tongue just right - you should be able to pull out the 5mm and slide the PU over the taper, down the line and over the part with the core. From here on, use the ball-thingy to push the PU tube down to the CL body. Smooth out the 5mm over the core and seat it hard against the body of the CL.

9. Fit the spinning handle onto the PU tubing ... using a smaller core makes life easier - zero strain with the 1.75mm LashIt!. Leave the screws just snugged-up for now.

10. Make sure the 5mm is smooth and taught over the core; measure 40cm from the spinning handle body (40cm is standard for FS kites - J. suggests 40-45cm; my SA2.5 is 48cm) and then figure out how much you need for a Bowline ...

11. Cut the line off square and secure the tip with heat-shrink or whipping - and lock stitch ... I had planned to cut 1.1m of 5mm and end up with 1m of depower line but somehow it ended up as a finished length of 70cm which is about perfect - you can easily (kinda!) tie a bowline at the trim strap and still have 45cm of depower. That's before it's put under load and tightens up ...

 


12. Feed the depower line through the bar, fit the gust absorber and feed/pull through the trim strap - make sure there's some 8mm OD PU tubing in there!

13. Bowline at the trim strap. Get it tight! It'll all snug up on the next flight, so be prepared to adjust front leader lines or mixer 0_o'

14. Tidy it all up; refit the suicide-leash loop, tighten the screws on the spinning handle (make sure it and the PU tubing is seated hard against the CL body), cover the gust absorber.



15. Go fly! Check to stretch etc and SailKote the line!

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