L3 Project Build Thread - Performance Rocketry Competitor 4

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cherokeej said:
This is from my Comp 4. Coincidence? :grin:

Work-horse rocket. Great choice for an L3 cert. Fly's well on thrusty K's, but will eat an M for lunch, and come back hungry.
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Sweet!

I'm down to 2 choices for a main chute - either a SkyAngle Cert-3 L Main or the Rocketman 10 ft Main. Any advice either way? What are the dimensions of the SkyAngle Cert-3 L?
 
AlnessW said:
Sweet!

I'm down to 2 choices for a main chute - either a SkyAngle Cert-3 L Main or the Rocketman 10 ft Main. Any advice either way? What are the dimensions of the SkyAngle Cert-3 L?
Click to expand...

I wouldn't compare dimensions. I would compare descent rates. Unless you have a payload space problem and even then it is packed volume.
 
AlnessW said:
Sweet!

I'm down to 2 choices for a main chute - either a SkyAngle Cert-3 L Main or the Rocketman 10 ft Main. Any advice either way? What are the dimensions of the SkyAngle Cert-3 L?
Click to expand...

https://shop.locprecision.com/category.sc?categoryId=29

These parachutes are comparable to the Sky Angle for less money. I just purchased a drogue and an XL for my L3, and am very impressed with the quality. You can also custom order specific colors for each panel.
 
AlnessW said:
Sweet!

I'm down to 2 choices for a main chute - either a SkyAngle Cert-3 L Main or the Rocketman 10 ft Main. Any advice either way? What are the dimensions of the SkyAngle Cert-3 L?
Click to expand...

I don't think you need one all that big. Mine uses an 84" Top Flite, and mine is built a little heavy. Not fancy, but it doesn't need to be.

You might consider a Fruity Chutes Iris. It has an astronomical coefficient of drag, and they fold small. Check Gene's site. He has a descent rate calculator there. :2:
 
I chose a Spherachute 84" for my Comp 4. While we have tons and tons of recovery space, I went for a slightly faster decent rate to try to help keep it inside the waiver cylinder for the certification flight. The desert floor out there is quite soft so other than some paint damage, I am not concerned with the landing.
 
dixontj93060 said:
I wouldn't compare dimensions. I would compare descent rates. Unless you have a payload space problem and even then it is packed volume.
Click to expand...
So the dry weight of this rocket, with an empty motor case, comes to about 16 pounds. Chute space isn't a problem, the main bay is 36" long.

dosmithii said:
https://shop.locprecision.com/category.sc?categoryId=29

These parachutes are comparable to the Sky Angle for less money. I just purchased a drogue and an XL for my L3, and am very impressed with the quality. You can also custom order specific colors for each panel.
Click to expand...
Cool, thanks!

chuck5395 said:
Have you considered a chute from one of our NXRS sponsors, Fruity Chutes?
Click to expand...
I definitely have. However, in the spirit of keeping things simple, David suggested SkyAngle/Rocketman for the 4 lines.

jackman said:
I'll second cherokeej. I'm also using a Top Flite 84" which gives me a descent rate of 22 ft/sec.
Click to expand...
I think that chute has 16 lines?

Demonian said:
I chose a Spherachute 84" for my Comp 4. While we have tons and tons of recovery space, I went for a slightly faster decent rate to try to help keep it inside the waiver cylinder for the certification flight. The desert floor out there is quite soft so other than some paint damage, I am not concerned with the landing.
Click to expand...

That's a very valid point about the waiver cylinder. Brothers is 1.5 miles?

Let's see. Using the rocketreviews.com decent rate calculator, it suggested a 9 ft main for an 18 fps decent rate. Garibaldi suggested 15-18 fps.

Decisions, decisions...
 
jackman said:
That may be right. I haven't counted them but I know there's a lot of 'em. I'm very careful about packing the chute for that reason.
Click to expand...
I just checked the Top Flight website and it does indeed say 16 lines:
https://topflightrecoveryllc.com/

Like you mention, that's a lot to keep track of. IMO, a chute with that many lines adds unnecessary complexity to a cert flight. 4 lines seems like a nice way to go...
 
AlnessW said:
I just checked the Top Flight website and it does indeed say 16 lines:
https://topflightrecoveryllc.com/

Like you mention, that's a lot to keep track of. IMO, a chute with that many lines adds unnecessary complexity to a cert flight. 4 lines seems like a nice way to go...
Click to expand...

It's an L3. Surely an L3 flier ought to be able to handle the complexity...

Also, if you use a deployment bag (HIGHLY recommended!) then the number of shroud lines makes absolutely no difference.
 
CarVac said:
It's an L3. Surely an L3 flier ought to be able to handle the complexity...

Also, if you use a deployment bag (HIGHLY recommended!) then the number of shroud lines makes absolutely no difference.
Click to expand...
Sure. But why over-complicate things if it's not needed? That's what my TAP suggested, anyways. Will probably use a deployment bag.

Demonian said:
I belive 1.5 miles is correct.

All this parachute talk made me dig mine out to have a look. Silly me, I bought a 72", for some reason... So on the hunt for a more appropriately sized parachute I remembered this one...

https://rocketrywarehouse.com/product_info.php?products_id=306

I like the price point and the shroud line count. Food for thought anyway.
Click to expand...
Another good option indeed! How is your project coming along, by the way?
 
Slow but sure...

Altimeter bay is complete, paint is about done, just waiting the requisite week or two for a full cure before I start the final stages of wet sanding and clear coating. I think all I have left is the tracking bay and some finalization of the recovery gear.

I took a job in Bend so I am moving next week. Not sure if I will be ready for a shakedown flight in May, but I am sure going to try.
 
Demonian said:
Slow but sure...

Altimeter bay is complete, paint is about done, just waiting the requisite week or two for a full cure before I start the final stages of wet sanding and clear coating. I think all I have left is the tracking bay and some finalization of the recovery gear.

I took a job in Bend so I am moving next week. Not sure if I will be ready for a shakedown flight in May, but I am sure going to try.
Click to expand...

Awesome Darren. Good progress indeed! You're moving to Bend? Well hey, you'll be that much closer to Brothers now! :) At the rate I'm progressing I'll definitely be ready for a May checkride flight.
 
IMG_2019.jpg
Last weekend I headed over to the local "mom and pop" feed/hardware store for some various, er, hardware that I needed for the nosecone and recovery harnesses.

IMG_2022.jpg
Drogue harness assembled - 36' of tubular nylon, and a SkyAngle Cert-3 Drogue. (24") The harness is attached to the forward end of the motor, and then the other end attaches to the eyebolt on the drogue end of the av-bay.

IMG_2020.jpg
Now, onto the nosecone. The "anchors" consist of 2.5" 10-24 machine screws with hex nuts. First, they are tacked inside the nosecone coupler (this was probably the hardest part) using standard hobby epoxy.

IMG_2027.jpg
... And then secured and epoxied in place with Kevlar soaked in West Systems epoxy. Vern has a much more detailed description of how this is done on his website:
https://vernk.com/Construction/AngelfireNosecone.htm

IMG_2028.jpg
Completed nosecone with bulkhead and forged eyebolt. Seems bulletproof to me...
 

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The sun is shining here in Portland, so I couldn't resist a quick photo op...

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Just caught up with this thread... that bird looks wicked!!!

This gives me yet another reason to go to NXRS!
 
Salvage-1 said:
Just caught up with this thread... that bird looks wicked!!!

This gives me yet another reason to go to NXRS!
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Hi Rob, great to hear from you! Thanks for the kind words.

You should definitely attend NXRS this year! Ever been before?
 
nope. not been to NXRS before, last year the girls had a dance recital that weekend and the year before ..erm dunno; but since i missed all the big ones last year.... i aint missing this one
 
Salvage-1 said:
nope. not been to NXRS before, last year the girls had a dance recital that weekend and the year before ..erm dunno; but since i missed all the big ones last year.... i aint missing this one
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You definitely won't want to miss NXRS this year. :wink:
 
This winter has been spent 'rebuilding'. I lost my Ventris, broke the fins off my 3" Kraken, busted up the cluster Kraken, and buried both stages of my nice Wallace and Grommit two stage.
A new Kraken is being built, which has its own surprises, rebuilding Wallace and Grommit, and am thinking of a two stage Jart, 54mm airframe with 38mm in each stage.

I had thought about my L3, and have it all designed, but that will wait until next year. You would never have guessed, but it is a Blue Tube tubefin (nearly but not quite a copy of the Extreme Paralyser by Rick Dunseith)

I am really looking forward to seeing your Wildman rip!! I may even have to finish my 3" Darkstar!!

tubie 75 clusta 3d.jpg

tubie 75 clusta bottom.jpg

tubie 75 clusta.jpg
 
Salvage-1 said:
This winter has been spent 'rebuilding'. I lost my Ventris, broke the fins off my 3" Kraken, busted up the cluster Kraken, and buried both stages of my nice Wallace and Grommit two stage.
A new Kraken is being built, which has its own surprises, rebuilding Wallace and Grommit, and am thinking of a two stage Jart, 54mm airframe with 38mm in each stage.

I had thought about my L3, and have it all designed, but that will wait until next year. You would never have guessed, but it is a Blue Tube tubefin (nearly but not quite a copy of the Extreme Paralyser by Rick Dunseith)

I am really looking forward to seeing your Wildman rip!! I may even have to finish my 3" Darkstar!!
Click to expand...

Oh boy...lots of rebuilding indeed! I remember seeing Wallace and Gromit crash at Rocketober - that was sad...
https://www.oregonrocketry.com/wp-content/gallery/rocketober_2013/rocketober_2013-89.jpg

A 2-stage Jart sounds awesome, and a tubefin rocket for an L3 project?? Never would have guessed! :) Looks like a cool design, too.

I can't wait to fly the Competitor 4 either, it'll be up at both the May launch and NXRS!
 
Finally finished the sled, having put that project on hold for a bit while I had to wait on mounting hardware.

IMG_2032.jpg
Altimeters mounted in place and all wired up.

IMG_2033.jpg
Those loose wires will eventually have connectors of some sort.

IMG_2034.jpg
Back side of the sled - twin 9V batteries and 2 push-button on/off switches, a design inspired by fellow forum members jackman and chuck5395.
 

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