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dhkaiser

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I am building my first 4" rocket, a Mac Performance Sky Scraper. In all my smaller SD rockets I have used just one swivel. On this rocket I have a three loop harness. What is recommended? One swivel below the main, or one each below the main and NC? One on each loop? What do you do?
 

Onebadhawk

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After I fly a drogue chute if it is unbalanced and spins I put a swivel on it..
If I have a rocket that the booster has a tendency to spin I put a swivel on the bottom of the boosters harness,,
so the booster can spin without twisting up the harness..

Teddy
 

CzTeacherMan

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After I fly a drogue chute if it is unbalanced and spins I put a swivel on it..
If I have a rocket that the booster has a tendency to spin I put a swivel on the bottom of the boosters harness,,
so the booster can spin without twisting up the harness..

Teddy
+1.
 

dhkaiser

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After I fly a drogue chute if it is unbalanced and spins I put a swivel on it..
If I have a rocket that the booster has a tendency to spin I put a swivel on the bottom of the boosters harness,,
so the booster can spin without twisting up the harness..

Teddy
Thanks Teddy! I received your harness today and am impressed with the quality. Another question, this rocket will weight in around 10 -11 lbs. Which sized quick link and swivel would you recommend?
 

Rob702Martinez

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I order all my recovery equipment from Teddy. FWIW i flew my 4" drago had problems tangling, I used the Big bolt swivels on his site about a foot out from the airframe. A swivel on the drouge and main. Worked so good that I converted all my HPR that way, never had a problem after that.
 

o1d_dude

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Teddy nailed it. Should have talked to him and saved myself three test flights, arriving at the same conclusion.
 

Onebadhawk

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Thanks Teddy! I received your harness today and am impressed with the quality. Another question, this rocket will weight in around 10 -11 lbs. Which sized quick link and swivel would you recommend?
Heyyy,, thank you guy's so much...
Now that's a Christmas present,, lol...

I'm sorry, I didn't see this before..

Guy's,, take a look at the swivels on my site..

The basic material I work with..

3/16" Tubular Kevlar or 9/16" Tubular Nylon...
11/32" Tubular Kevlar or 3/4" Tubular Nylon...
7/16" Tubular Kevlar or 1" Tubular Nylon...

The 3 heavy swivels --

3/16" Polished Stainless Steel Swivel-- 300 lb. WLL -- $6
1/4" Polished Stainless Steel Swivel-- 600 lb. WLL -- $8
5/16" Polished Stainless Steel Swivel-- 1100 lb. WLL -- $14

Please be aware,, I also have the standard 500 lb stainless ball bearing fishing type swivel I put on 3rd loops for the drogue..
I have 1500 lb Spro stainless ball bearing fishing type swivels for the same purpose..

I also do a lot of work for really big heavy rockets..
So I have what I refer to as tug boat material,, lol..
3/4" Tubular Kevlar and 3/8" heavy Polished Stainless Steel Swivels for it...

Daniel,, you got a 7/16" Tubular Kevlar harness..
These are the swivels I put on that material-- 5/16" Polished Stainless Steel Swivel-- 1100 lb. WLL

Thank you always guy's,,

I wish for everyone a wonderful Christmas full of Love, Family, Laughter, and just a bit too much cheer...

Teddy
 

kevinkal

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Guy's,, take a look at the swivels on my site..

The basic material I work with..

3/16" Tubular Kevlar or 9/16" Tubular Nylon...
11/32" Tubular Kevlar or 3/4" Tubular Nylon...
7/16" Tubular Kevlar or 1" Tubular Nylon...

The 3 heavy swivels --

3/16" Polished Stainless Steel Swivel-- 300 lb. WLL -- $6
1/4" Polished Stainless Steel Swivel-- 600 lb. WLL -- $8
5/16" Polished Stainless Steel Swivel-- 1100 lb. WLL -- $14

Please be aware,, I also have the standard 500 lb stainless ball bearing fishing type swivel I put on 3rd loops for the drogue..
I have 1500 lb Spro stainless ball bearing fishing type swivels for the same purpose..
Ted,
I'm about to start building up a 4" Fiberglass rocket that will be 24 lbs on the pad and about 18 pounds after burnout. I have both your 2 loop and 3 loop 7/16" tubular Kevlar harnesses for it. I rather like the smooth operation of the ball bearing swivels and have been using one with good results on the bridal of a main parachute. I have a 500 lb rated ball bearing swivel on hand that I am considering for use in this build. I looks very similar to the ball bearing swivel that is pictured in your web site hardware swivels page, the one on the far left of the image.. which is pasted below. What is the Working Load Limit for the ball bearing swivel on the left?
OneBadHawkSwivelPicture_orig.jpg
Thanks.

Also, does anyone know what the failure mode would be for the ball bearing swivel.. does it begin to yield at the load rating but hold together for a fair amount of additional load before failure?
 
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Handeman

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I only use ball bearing swivels for DD rockets. And I only attach one to the fin can.

I tried a non-ball bearing swivel once and it came back from it's first flight deformed and the cord was all wound up.

I also have never had a chute, main or drogue that spun enough to need a swivel. I've never had a fin can that didn't spin. That doesn't mean it won't happen, but it hasn't so far. So, my SOP is a ball bearing swivel on the fin can and add other swivels if needed like Teddy said.

I also don't go overboard with swivel strength and weight. As long as you use a drogue that keeps the fin can below the payload, don't use too long of shock cords and don't over do the ejection charges, you won't be putting excessive loads on the swivel.

Good luck....
 
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