Most people will poo-poo this, but on my Formula 75, I epoxied the harness to the inside of the NC. It has held up for 5 or 6 flights so far and shows no sign of wear.
Head-End Dual Deployment Details & Explanations Requested
- Thread starter Viperfixr
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Great thread, thanks for the pictures.
Tim51
Well-Known Member
Thanks - good to know. If it works on a F75, it'll work on the project I have in mind.. [emoji1]
blackjack2564
Crazy Jim's Gone Banana's
Think outside the box...we don't need no stink'n E-bolt..lol just a loop!
When building rockets you must come up with all types of strange solutions...lol
On lightweight plastic cones..[all of them lol] I make a loop of 1/4 kevlar [or anything] tie it together with your favorite knot, I just use an overhand.
Slip a washer and 1/4 inch nut over kevlar and slide down to the knot.
Scuff up inside tip with screwdriver or end of file.
Drop it in NC and foam the tip 3-4 inches . 2 part urethane foam [wildman sells it.PML sell it etc.]
NC being plastic and foam can create heat, put it in water to keep from deforming.
This one was in the instructions for wildman Sport, which was single deploy so I didn't care how much was used.Obviously you need less and need room for chute in HED.
Size glass to cone and I fill with ice/water. Trust me foam STICKS to anything and stays put!
When building rockets you must come up with all types of strange solutions...lol
On lightweight plastic cones..[all of them lol] I make a loop of 1/4 kevlar [or anything] tie it together with your favorite knot, I just use an overhand.
Slip a washer and 1/4 inch nut over kevlar and slide down to the knot.
Scuff up inside tip with screwdriver or end of file.
Drop it in NC and foam the tip 3-4 inches . 2 part urethane foam [wildman sells it.PML sell it etc.]
NC being plastic and foam can create heat, put it in water to keep from deforming.
This one was in the instructions for wildman Sport, which was single deploy so I didn't care how much was used.Obviously you need less and need room for chute in HED.
Size glass to cone and I fill with ice/water. Trust me foam STICKS to anything and stays put!
Tim51
Well-Known Member
Finally got round to flying a (sorta) DIY HED arrangement over the weekend. I picked up an old second hand gelcoat 4" NC a while ago. The interior was too rough and uneven to allow a smooth fit of the Av coupler, so rather than saw the NC shoulder off I made a short 'collar' from a length of aiframe, so the shoulder of the NC butted up to the forward bulkplate of the Av bay. I used an existing Av bay and a 4" booster from two different earlier projects. So slight adjustments but the basic principle was the same - main chute packed in NC. Cloud base was pretty low so I flew it on an I345 - Dual deploy wasn't really necessary given the altitude (SLCF said 1983') but it was a nice little low 'n' slow try out..
Flight picture courtesy H.A.R.T. Rockets
Flight picture courtesy H.A.R.T. Rockets
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blackjack2564
Crazy Jim's Gone Banana's
Glad it worked out good for ya Tim! Thinking outside the box works wonders.
Serac
Well-Known Member
The more l look at this approach, the more I like it. Is there any reason why this isn't the default/preferred DD approach? The complication of mounting the shock chord to the NC?
blackjack2564
Crazy Jim's Gone Banana's
It works fantastic for shorter scale rockets where no room or high performance where every inch counts.
But also needs good packing skills.
Most just prefer a large bay for chutes and sport flying...there are as many reasons as there are fliers...lol
You find several kits now with HED [head end reply] out there, Wildman Jarts...Punishers..and several more.
Fiberglass spiral wound cones are easy conversion, since couple/shoulder can be converted to av-bay by just adding a vent band....easy peasy .
The issue I was addressing was converting plastic cones with built in shoulder, which has it's own complications,but you are right it saves weight...higher flights...better performance.
But also needs good packing skills.
Most just prefer a large bay for chutes and sport flying...there are as many reasons as there are fliers...lol
You find several kits now with HED [head end reply] out there, Wildman Jarts...Punishers..and several more.
Fiberglass spiral wound cones are easy conversion, since couple/shoulder can be converted to av-bay by just adding a vent band....easy peasy .
The issue I was addressing was converting plastic cones with built in shoulder, which has it's own complications,but you are right it saves weight...higher flights...better performance.
