L2 decisions

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AfterBurners

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At first I thought when going for my L2 I was going to get a kit and build it and call it done, (Punisher Kit) but now I'm leaning toward a scratch build. I honestly feel I would gain a lot more experience from it and it would be more rewarding.

I haven't decided on materials yet. I know there are a lot to choose from. I'm thinking QT from PML

For sure it will be DD and I'm considering a cluster as well.

For a lot of you guys out there that have a few DD flights under belt as well as rockets. Do you build your eBays so they interchange between rockets?
 
For no reason at all, I have one bay for several 4" rockets, 3 different 3" bays (all matching glass...no idea why I don't share) and 2 2.6" bays, but one's bluetube and one's thinwall glass.


I can say, the 4" bluetube bay I have and swap around I'm VERY happy with. Makes things very easy. I know many people just swap sleds around, but I've fired this bay multiple times the same day and it worked out very well.
 
I made my 54 mm ebay so it would work in my 3 inch rockets, my 4 inch ebay works with 5.5 inch loc stuff, and my 6 inch ebay handles everything bigger.

Don't forget that clusters aren't a cert allowable activity. And it's not KISS, which is the cert mantra.....
 
At first I thought when going for my L2 I was going to get a kit and build it and call it done, (Punisher Kit) but now I'm leaning toward a scratch build. I honestly feel I would gain a lot more experience from it and it would be more rewarding.

I haven't decided on materials yet. I know there are a lot to choose from. I'm thinking QT from PML

For sure it will be DD and I'm considering a cluster as well.

For a lot of you guys out there that have a few DD flights under belt as well as rockets. Do you build your eBays so they interchange between rockets?

QT is very easy to work with, sands well, paints amazing but it's not the strongest of the materials, rated at .85 mach. Taking price, strength, and ease or working with into consideration, it's hard to beat the new thin wall FG and new polycarbonate with phenolic tip nosecone materials today.

Dual deploy as you likely know that it's not required nor is electronics for the Tripoli L2 not sure about others. But I have been using them since my first HPR build and don't subscribe to the just get it done philosophy on the certification process so I would never discourage you from challenging yourself and taking some risks.

L2 and I think all of the certifications have to be done on a single commercial motor, so no staging or clusters.

For me I have experimented with C02, cable cutters, deployment bags, custom deployment bags, drogues, pilots, etc. so my bays have been all over the place in design. As a result so far I have dedicated electronics for each rocket. But now that I am getting into some of the larger airframes as well as figuring this stuff out it should be easier to make interchangeable AV altimeter bays, at least that is the plan. I am just building my first AV bay for dual trackers to swap between nosecones.
 
NAR allows clusters, but :

"....In the case of a cluster or staged model, at least one of the individual motors must be an J, K or L impulse motor. Combinations of smaller impulse motors that add up to meet the impulse requirements do not qualify as the model does not contain at least one J, K or L impulse motor......"
 
I made my 54 mm ebay so it would work in my 3 inch rockets, my 4 inch ebay works with 5.5 inch loc stuff, and my 6 inch ebay handles everything bigger.

Don't forget that clusters aren't a cert allowable activity. And it's not KISS, which is the cert mantra.....

You can fly clusters as long as one is a "J" impulse or higher
 
QT is very easy to work with, sands well, paints amazing but it's not the strongest of the materials, rated at .85 mach. Taking price, strength, and ease or working with into consideration, it's hard to beat the new thin wall FG and new polycarbonate with phenolic tip nosecone materials today.

Dual deploy as you likely know that it's not required nor is electronics for the Tripoli L2 not sure about others. But I have been using them since my first HPR build and don't subscribe to the just get it done philosophy on the certification process so I would never discourage you from challenging yourself and taking some risks.

L2 and I think all of the certifications have to be done on a single commercial motor, so no staging or clusters.

For me I have experimented with C02, cable cutters, deployment bags, custom deployment bags, drogues, pilots, etc. so my bays have been all over the place in design. As a result so far I have dedicated electronics for each rocket. But now that I am getting into some of the larger airframes as well as figuring this stuff out it should be easier to make interchangeable AV altimeter bays, at least that is the plan. I am just building my first AV bay for dual trackers to swap between nosecones.

I would think having electronics for each rocket would be pricey as well
 
I want to challenge myself with tis build which is why I want to go DD and maybe a cluster? Depends on motor costs, but DD for sure. I plan on flying everything here on out after I get L2 on DD. It makes sense. Why would I want to go 2 miles to get a rocket?
 
I approach it with each rocket having its own ebay. I move the altimeters as needed.
 
At first I thought when going for my L2 I was going to get a kit and build it and call it done, (Punisher Kit) but now I'm leaning toward a scratch build. I honestly feel I would gain a lot more experience from it and it would be more rewarding.

I haven't decided on materials yet. I know there are a lot to choose from. I'm thinking QT from PML

QT is nice stuff and finishes great but remember that it cannot handle mach+ flights. There is a disclaimer on their web site somewhere.



For sure it will be DD and I'm considering a cluster as well.

Why is that? Just want to certify in style? Not really my cup of tea but that doesn't mean it's wrong to certify on a cluster. Most prefer to just keep it simple.

For a lot of you guys out there that have a few DD flights under belt as well as rockets. Do you build your eBays so they interchange between rockets?

Not me. I thought about doing that many moons ago. The issue for me personally is I derive a lot of joy from making each of my ebays a little different just because the challenge to come up with something I like and something that's different is enjoyable. Once again, there is nothing wrong with making interchangeable e-bays. A lot of people do that.

-Dave
 
The issue for me personally is I derive a lot of joy from making each of my ebays a little different just because the challenge to come up with something I like and something that's different is enjoyable.

Wow, glad I'm not the only crazy one. I have this innate need to do things differently nearly every time. It applies to rockets, yes, but anything remotely repetitive.
 
Same here. All my rockets are different colors. The switch band wouldn't look right off color.

That's why I built mine without a switch band. Push on/off switch is accessed through the vent hole. But I won't do that again, getting everything aligned so that the switch is directly below the hole is not easy.
 
QT is nice stuff and finishes great but remember that it cannot handle mach+ flights. There is a disclaimer on their web site somewhere.





Why is that? Just want to certify in style? Not really my cup of tea but that doesn't mean it's wrong to certify on a cluster. Most prefer to just keep it simple.



Not me. I thought about doing that many moons ago. The issue for me personally is I derive a lot of joy from making each of my ebays a little different just because the challenge to come up with something I like and something that's different is enjoyable. Once again, there is nothing wrong with making interchangeable e-bays. A lot of people do that.

-Dave

DD - Because it makes for me not to walk 2 miles to retrieve my rocket and mostly I like challenges. I never take the easy way out
 
I think DD may not be required for L2 but it is certainly recommended. It's to minimize the chance of losing the rocket and therefore certification. Tracker is helpful too.
 
It comes down to "to each their own"

There are a thousand ways to do an L2 flight....and no punishment for failure. So why not do something a little more complex if it makes you happy. Just don't take risks you're not ready for. If you feel ready, go for it
 
I generally try to share sleds between similar rockets, but not whole avbays.. So I have 1 sled for my 5.5-7.5" rockets, another for my 4" rockets, a third for 2.6-3" rockets, and one for 54 mm rockets. I move altimeters between sleds as necessary. That being said, I am on the third generation sled for 4" and second generation for 2.6-3 as I've learned what I like, what I don't like, and what works well. So I wouldn't worry about setting up your first sled/avbay to share, as you'll likely discover several changes you'll want to make on the next one.

David
 
I want to challenge myself with tis build which is why I want to go DD and maybe a cluster? Depends on motor costs, but DD for sure. I plan on flying everything here on out after I get L2 on DD. It makes sense. Why would I want to go 2 miles to get a rocket?

Having DD is no guarantee you won't land 2 miles out anyway.
 
Wow, glad I'm not the only crazy one. I have this innate need to do things differently nearly every time. It applies to rockets, yes, but anything remotely repetitive.

:horse:

It comes down to "to each their own"

There are a thousand ways to do an L2 flight....and no punishment for failure. So why not do something a little more complex if it makes you happy. Just don't take risks you're not ready for. If you feel ready, go for it

Yep yep yep. Completely agree.

DD - Because it makes for me not to walk 2 miles to retrieve my rocket and mostly I like challenges. I never take the easy way out

No, I was referring to the cluster part. Just curious if there was a specific reason or its one of those "just because" reasons. :cool:

Again, to each their own.
 
You could create different ebays for every rocket. I once did that. You just transfer the ebay between rockets - right?

May I suggest you consider transferring the sled with attached electronics between ebays of different rockets? Quicker, easier, and less fiddly - overall.

This is just how I do it. It works for me.

Good luck with your L2. I like your style.

Cheers

N
 
Howe many of you just went with a "J" motor no DD? What's the minimum size "J" you can fly for certification? I know there's a lot of baby "J's" in the 38 range just wondering what the cutoff is?
 
you need motor betwen 640.01 and 5120.00 n/sec total impulse, yout choice depend on the weight of the rocket.
 
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I had a fairly heavy rocket for my L2 cert, the altimeter showed 3900 feet. I couldn't see it at apogee. If the rocket came down on a single stage chute, I probably would never get it back (the wind was not strong at all).

So I think DD is still highly recommended.
 
Howe many of you just went with a "J" motor no DD? What's the minimum size "J" you can fly for certification? I know there's a lot of baby "J's" in the 38 range just wondering what the cutoff is?

I used a AT J350 in my LOC IROC. Didn't have the little portable altimeters back then, but wrasp predicted 3600ft. Motor deploy at apogee and not too bad a walk. It was a nice day ;)

Adrian
 
I believe most 38mm have motor ejection. I still use them as backup in case the altimeter fails...
 
I believe most 38mm have motor ejection. I still use them as backup in case the altimeter fails...

So at what size motor do you have to use an altimeter to fire the ejection charge? Looking on WM's site I noticed the SKU @ on a motor K1499N-P does the "P" stand for plug? Whereas the J500G-M does the "M" represent "Motor Ejection"
 
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