Reloadable motor systems questions

[Wrightme43]

Good Evening!

I have been mulling this over in my mind for two days, well really longer since I only slept for 2 hours last night. (Whole other story, but if you have restless leg syndrome, do not take Benadryl to help you sleep, and especially do not take more when you can't sleep)

So I have been reading on reloadable motors. I reload ammunition so I understand safety, but I lack any experience. That will just take time and doing it.

My plan is to get one of these two kits https://aerotech-rocketry.com/products/product_6884e3bb-9375-a3f8-ab43-42d8a31ec4ee (The Initiator) or
The ARREAUXBEE-HI https://aerotech-rocketry.com/products/product_0dff647f-5dcb-4055-102c-fe7d023033a9

The Arreauxbee-Hi just moves my heart. It looks exactly like I imagine a rocket should.

They both include 29mm screw on motor retention which I think is the most elegant solution, they both can fly on 24mm engines as well.

From what I understand after 3 flights on disposable motors the reloadable motor becomes equal in cost, then saves money every launch, unless you lose it, or
have a motor cato.

If you had it do over again, what would be the most efficient use of money to buy motor cases? I am getting very confused, because I don't even know how to assemble a reloadable motor case. I don't know what I need, and what I don't need.

I want to buy one reloadable 29mm case that will let me fly rockets. I am not super over the top excited about altitude. I like watching them go up, and come down. I don't want to waste money and buy things I don't need, and skip something that will open up whole new possibilities just because I missed a key piece of information.

I joined BluesRocks NAR 657, and my NAR is 117835. I intend to get my L1 high power certification, but I want that to go very smoothly, with no surprises. So in the future I will need to buy a 38mm case but I think I will know enough then to buy the right things.
I want to stick with Aerotech mainly because I like them.

Do any of you have any advice for me, or can you point me in the right direction for research?

I have Tim V's Model Rocket Design and Construction on the way.

I know I am asking lots of questions, and probably wearing some of you out.
I really appreciate any help you can offer me.
Thank you for taking the time to read this!

Steve

 

[SolarYellow]

The Hobbyline 29/40-120 has some excellent reload options for rockets in that class. I find it to be kind of a sweet spot for value. You could use it to build experience and then decide later what to do to get your L1. There are a lot of good options in 29mm for L1; consider a "starter set" when you're ready.

 

[Wrightme43]

Yes sir, thank you!

 

[tsmith1315]

Agreed. For an Aerotech kit, the 29/40-120 is almost a necessity. Look at all the reload kits available for it, from E to G:


I bought my case in the mid 90's and it's still flying.

If you think you may want to fly either of those kits on larger motors (L1), leave the baffle off the forward end of the motor tube so that longer motors will fit.

 

[kuririn]

AT 29/40-120 for 29mm
AT 24/40 for 24mm
And don't lose the rocket!

 

[samb]

The best way to start with reloads is to watch one of your new buddies at the rocket club build one or two or three. Nothing beats the up close and personal touch.
The (distant) second best way is to google “building an aerotech reload” and watch a video.
If you haven’t yet experienced the awesome “up” of composite propellant motors then I think a few single use flights would be a good way to start.

My $.02

 

[Steve Shannon]

Buy and make that kit and fly it on single use reloads while you ponder. I don’t know how many reloads it takes to recoup the cost of motor hardware, but I suspect it’s a larger number than 3.
The other thing is that there are different families of 29 mm motors. There’s the Hobbyline cases, which are good for up to a G, but for which no reloads that can be used for certification exist.
There are the RMS cases. They’re what you need for HPR, but you cannot use them with the reloads for the Hobbyline cases.
Then there are the CTI cases. That’s another company altogether and while they have a single family of 29mm cases (Pro29) that are very user friendly, they’ve had some quality control issues and as much as I like them I cannot in good faith steer a person towards investing in them.
So, like I say, I would fly single use or DMS motors while trying different types at launches. You might even run across some used cases or find a sale on cases (Black Friday is big for Wildman customers).

 

[prfesser]

For assembly of an Aerotech reloadable, all you need is the reloadable motor, a reload, and some grease. Tools are not required, though rubber gloves aren't a bad idea to prevent grease from getting everywhere. Type of grease isn't particularly important. Most flyers seem to use Super Lube teflon-containing grease. Only a tiny bit is needed to lube the o-rings and threads of the motor.

 

[jmasterj]

The reason to buy reloadable 29mm AT motors (hobbyline or high power) IMO, is avoiding Hazmat shipping charges. HAZ-free G motors feel way better than the opposite, and you can get your one certification H motor shipped without Hazmat charges because most of the high power 29mm reloads are HAZ-free.

 

[Handeman]

A quick check online showed that it would take about 10 flights on a 29/40-120 case vs. equivalent single use or LMS motors to break even. With F motors, not so much. A pair of HobbyLine F-52 reloads are actually a dollar or so more than a EnerJet F-52 or EconoMax F-67 two pack. So no breaking even there.

I agree with @jmasterj about not having to pay HAZmat fees alone can help shorten the payback on the cases.

My HobbyLine cases are at least 20 years old. I would recommend going with the cases and reloads unless you plan to get out of the hobby in a few years, or only make 10 or few 29mm G flights ever, or expect to lose the rocket and case every 10 or fewer flights. I doubt any of those cases are what you expect, so yes, get the 29/40-120 case and have fun. Reloading that case is excellent practice for the 38mm reloads you'll use when you get your L1.

 

[Wrightme43]

Thank you all for your help!

I have 2 F20W-7 composite single use motors for my Aspire. I am waiting on a replacement tube from Estes for a crushed Cherokee E tube. I have some D12 and E12 black powder motors as well.

My plan for the Sept. 9th club launch is to fly my first two mid power rockets on disposable motors. If every thing goes well I should be able to get 8 flights. If there is a problem or failure, I will figure what happened, and try again with low cost rockets. My only failures have been pond landings. The first two LP rockets I launched at the club, and my favorite crossfire isx at a dirt site retention pond. I want to use this launch day for practice before spending money on the reloadable system and the more expensive aerotech kits. I mean I can build 2 or 3 normal kits for the price of the aerotech kits. I want to have some experience flying larger heavier rockets on mid power in preparation for high power later. I figure this way I will have the ability to build small cheap midpower rockets to fly on disposable motors (maybe go super high or maybe break the speed of sound, whatever cool ideas I can come up with), and a couple larger heavier mid power rockets I can fly on reloadable motors, that I can practice with the chute release, and altimeters, and get experience down two pathways towards my high power certification flight.

From what you all have said it looks like the 29/40-120 is the way to go for a first reloadable purchase. Last night and today while my wife is out with the girls getting nails done, my son and I have been watching how to load and assemble the 29/40-120 it seems perfect for what I want to do, and where it isn't single use will fill in the gaps very well.

Thank you all again! I appreciate all the help and advice.

Steve

 

[SolarYellow]

The other thing is that there are different families of 29 mm motors. There’s the Hobbyline cases, which are good for up to a G, but for which no high power reloads exist.

Minor point. The G138 is an HP motor due to the average thrust being >80N. It appears to be an awesome motor, although I haven't seen one fly. However, relevant to the OP, because it's a G, it doesn't satisfy the requirements for an L1 cert flight. He'd still have to buy a SU H motor to cert, in order to be able to fly the G138 if he wanted to.

BTW, when I said starter set for 29mm, this is what I was talking about:
https://wildmanrocketry.com/collections/29mm/products/2918sc

 

[Wrightme43]

Solar Yellow, that looks very handy too, but a later purchase for someone like me just starting out.

 

[SolarYellow]

…a later purchase for someone like me just starting out.

That’s exactly what I meant.

 

[rocketace]

I’ll second the 29/40-120. Started with that almost 20yr ago and would not have changed that decision. My only input for reloadable motors is 1) Read and follow the directions every time. Some motors when you get to larger sizes have small differences. 2) Clean the case as soon as you can. Same day is best, but I wait no longer than 3 days. I just use baby wipes if I’m in the field, or water/dawn at home. For really stuck stuff CLP or soak in white vinegar for 30min 3) Assemble them at home. This is controversial as some see it as not as safe, but it’s no different than having a single use motor once loaded and you can do it without any distractions.

 

[carlsonmjc]

Do not forget the resale value of a 29/40/120. It would sell in less than a day here for 60 % of retail.

MC

 

[4regt4]

Thank you all for your help!

I have 2 F20W-7 composite single use motors for my Aspire. I am waiting on a replacement tube from Estes for a crushed Cherokee E tube. I have some D12 and E12 black powder motors as well.

My plan for the Sept. 9th club launch is to fly my first two mid power rockets on disposable motors. If every thing goes well I should be able to get 8 flights. If there is a problem or failure, I will figure what happened, and try again with low cost rockets. My only failures have been pond landings. The first two LP rockets I launched at the club, and my favorite crossfire isx at a dirt site retention pond. I want to use this launch day for practice before spending money on the reloadable system and the more expensive aerotech kits. I mean I can build 2 or 3 normal kits for the price of the aerotech kits. I want to have some experience flying larger heavier rockets on mid power in preparation for high power later. I figure this way I will have the ability to build small cheap midpower rockets to fly on disposable motors (maybe go super high or maybe break the speed of sound, whatever cool ideas I can come up with), and a couple larger heavier mid power rockets I can fly on reloadable motors, that I can practice with the chute release, and altimeters, and get experience down two pathways towards my high power certification flight.

From what you all have said it looks like the 29/40-120 is the way to go for a first reloadable purchase. Last night and today while my wife is out with the girls getting nails done, my son and I have been watching how to load and assemble the 29/40-120 it seems perfect for what I want to do, and where it isn't single use will fill in the gaps very well.

Thank you all again! I appreciate all the help and advice.

Steve

I'll second the comment about also getting a 24/40. I use it frequently in my 29mm rockets - including a couple of Aerotech kits - on small fields. The F39 works well, it puts an AT Cheetah to over 1100ft. And it's useful on 1st flight/test flights on rockets that you plan on usually flying on just 29mm motors.

Hans.

 

[jmasterj]

Second the awesomeness of the 24/40. F24W is my favorite 24mm motor, and the F12 is a blast in odd-rocs.

 

[bad_idea]

In addition to saving on HAZMAT fees (less important if you have a local vendor), buying cases used can help speed the ROI. There's always someone getting out of a particular brand or size of case (or, sadly, out of rocketry altogether). Also keep an eye out for discounts and sales, especially around Black Friday. Aerotech's RAS and Cesaroni's case spacers also help cut down on case costs by allowing you to fly smaller loads in bigger cases, limiting the number of cases you need.

Another incentive to buy cases is the variety of loads and the ability to pick and choose closures. There are far more loads available as reloads than as single-use. That said, there are some fantastic single-use motors available in almost every segment of the market (from MicroMax to O impulse).

@rocketace speaks the truth about building motors at home. If you do build at the field, make sure to kick anyone distracting you out of your workspace. And if you see someone building a motor, please don't pester them while they work.

 

[prfesser]

I'm one of those strange ducks who likes assembling reloadables (cleaning...not so much... ) Bought a 24/40 motor case, it now has an F39 loaded. Hoping that my Interceptor E will successfully lose its rocket-virginity this weekend on that motor.

 

[jmasterj]

I'm one of those strange ducks who likes assembling reloadables (cleaning...not so much... ) Bought a 24/40 motor case, it now has an F39 loaded. Hoping that my Interceptor E will successfully lose its rocket-virginity this weekend on that motor.

You're at least not a unique strange duck. I too enjoy assembling motors.

 

[loopy]

You're at least not a unique strage duck. I too enjoy assembling motors.

Ditto.

 

[gldknght]

You're at least not a unique strange duck. I too enjoy assembling motors.

Me too!

I started out in mid power rocketry with the 29/40-120. I still have it. Actually, I have three. I had four, but the God of rockets confiscated one in an Aerotech Mustang in flight. He kept the rocket, too.

 

[SolarYellow]

FWIW, Hobbylinc has the 18/20 on sale for $40.19 right now. They've also dropped HAZ on G and down in accordance with the new procedures.

 

[bad_idea]

FWIW, Hobbylinc has the 18/20 on sale for $40.19 right now.

Thankfully I already have seven of those, else you would have just cost me more money. Again.

 

[smstachwick]

The RSM 29/40-120 Type F loads probably have the most improvement. For whatever reason I think they had the only HAZMAT fees of the bunch, with the F-sized grains being a hair too massive to duck under the limit but the G grains being just right.

I’d be pretty interested in flying my upcoming L1 build on an F52T.