Do I invest in RMS right from the get go?

[Kframe]

I'm just getting into high power and am trying to decide whether I make the jump to RMS right away, or fly on DMS for some time before getting into reloadable motors.
There are a few things I'm considering, and others I may not be aware of but should factor into the decision.
*Right now I have 29mm and 38mm MMT rockets, at some point 54mm is likely.
*I plan on earning L1 this summer, and possibly L2 this year as well.
*As far as I know there are no brick & mortar places in the MN Twin Cities area that I can buy motors so I would have to have things shipped and DMS = Hazmat fees.
*I will have to drive over an hour to launch HPR so realistically I would probably be going to 3-5 launches each year at most, and while there would want to launch each rocket more than once, to make the drive worth it.

Any opinions or advice on this is welcome, thank you!
-Kris

 

[Hobie1dog]

are there any vendors that show up at your launches that you could buy the motors from?

 

[David Schwantz]

You are wrong about buying motors in MN. Off We Go Rocketry is in business, you can call and make appointment to go to Gary's and buy direct from him. He is great to deal with. He is also our vendor at the launches. there are 2 clubs in MN, north and south. Both are great. I fly at the North Branch field. Have you been to one of our launches? Dave.

https://www.offwegorocketry.com/

 

[sharkbait]

I'm just getting into high power and am trying to decide whether I make the jump to RMS right away, or fly on DMS for some time before getting into reloadable motors.
There are a few things I'm considering, and others I may not be aware of but should factor into the decision.
*Right now I have 29mm and 38mm MMT rockets, at some point 54mm is likely.
*I plan on earning L1 this summer, and possibly L2 this year as well.
*As far as I know there are no brick & mortar places in the MN Twin Cities area that I can buy motors so I would have to have things shipped and DMS = Hazmat fees.
*I will have to drive over an hour to launch HPR so realistically I would probably be going to 3-5 launches each year at most, and while there would want to launch each rocket more than once, to make the drive worth it.

Any opinions or advice on this is welcome, thank you!
-Kris

Nothing wrong with doing both, start building up your hardware and have some DMS on hand so you can get that second flight in on launch day

 

[Neutronium95]

Here are my thoughts on reloads vs single use for various situations.

If you want to avoid Hazmat fees, look at Aerotech 29mm hardware, and Loki 38mm hardware. Aerotech has a few non Hazmat 38mm reloads, but there aren't nearly as many options as Loki has in that size. Cesaroni does not make any non hazmat reloads in any motor size.

If you want to reuse the casing multiple times in a day, I'm a fan of Cesaroni 29mm motors. They require essentially no cleaning, and with experience can be reloaded much faster than Aerotech. I imagine their 38mm motors are similarly quick to turn around, but I don't really fly them enough to say for certain.

I think that the best case for DMS is in 38mm. There are a number of good options, and the motors aren't really any more expensive than reloads, for example the difference in price between the RMS and DMS H550 is a single dollar. In 29mm, most Aerotech RMS motors are non hazmat, and in the larger motors, RMS starts to come out ahead in price per flight.

Historically, Aerotech has had more expensive hardware, but cheaper reloads than Cesaroni. Loki typically is the most expensive, but has some amazing options, and a big selection of non hazmat 38mm motors. Cesaroni has also had some supply problems recently, with vendors waiting months for orders, so keep that in mind. Aerotech motors also typically have the best deals and sales. Wildman had 32% off Aerotech motors on his Wednesday members sale this year, and Balsa Machining has 25% off reloads and DMS motors when you preorder, and 40% off on a few select DMS motors.

 

[Kframe]

You are wrong about buying motors in MN. Off We Go Rocketry is in business, you can call and make appointment to go to Gary's and buy direct from him. He is great to deal with. He is also our vendor at the launches. there are 2 clubs in MN, north and south. Both are great. I fly at the North Branch field. Have you been to one of our launches? Dave.

https://www.offwegorocketry.com/

Thank you! I have not yet been up to North Branch but plan to as soon as it’s spring!

 

[StreuB1]

I always tell people looking to start out, to go with this.

https://wildmanrocketry.com/collections/29mm/products/2918sc
Also, get the Wildman Club Membership. Its $30 and it pays for itself just by buying this hardware kit.

There is a LOT that you can do with the 29mm HPR RMS hardware.

 

[David Schwantz]

As far as hardware goes, with RMS you will have many more motor choices. I like both DMS and RMS. To get as many flights in a day I will have all rockets prepped for flight the night before, even down to the flight cards. If you need to prep for a second flight having a RMS built and ready to install takes less time.

 

[David Schwantz]

I am in the south metro. Is that near you?

 

[Handeman]

My first question, how long do you intend to fly HPR?

If the answer is for "years" then go with RMS. You will save money over time. It might not be this year, or next, or even the year after that, but eventually you will see savings using RMS, if you even care after you've had the HW for a couple years. The longer you use DMS/SU, the longer it will take to get the RMS hardware and realize the savings. I still have and use the AT 29/40-120 motor I bought 20 years ago. Just the savings on the RMS in that case over SU F & G motors probably paid for most of the other cases I've bought over the years, at least up to 54mm.

When I started buying hardware, CTI wasn't even an option. After my L1, I started with an AT 29/180 motor and a 29/240 case, reusing the closures from the 29/180.

I then bought a 38/360 motor and 480 case to expand my L1 well into the I range. Once I wanted to try L2, I bought a 38/720 case. Next was a great deal on a 54/1280 and a used 1706 case.
These cases pretty much cover the impulse range from small H to mid-K. CTI was available by then and I got a 6GXL case with spacers so I could fly the 5G - 6GXL motors that fit the impulse range above the 54/1706 case.

75mm Motors didn't come along until my L3 and I bought all snap ring cases because I was mixing my own EX motors for that size after my initial cert.

Along the way I have filled in my AT 38mm casings with the 38/240 and 38/600 and a few more closures for each size.

I have duplicate AT cases in some sizes now, but I've found that with the right size brush and baby wipes, I can clean a case and reload it in less then 10 minutes. The cleaning and reloading time is never an issue with how many launches I can get done in a day, it's the talking to, catching up with, helping others, LCO and RSO duty the cuts into the prep and launch time. Then again, I don't think I want rocket prep to cut into all of those other thing too much because the social aspect is a big part of what I love about this hobby.

This was a journey that started 20 years ago and is ongoing. I never flew a SU motor above a G in that time. I just bought another case if I felt the need for a particular motor. I stuck with AT for the 24, 29, 38, and small 54mm motors. Large 54mm is still the CTI 6GXL case. The number and sizes of 38, 54, and 75mm snap ring cases have expanded and I'm now looking at 98mm snap ring motors.

What ever you decide, I strongly recommend you look at this as a decades long endeavor and don't just make decisions on cost vs. savings in the short term.

 

[Kframe]

I am in the south metro. Is that near you?

Northfield

 

[GalantVR41062]

I am in Plymouth and fly Tripoli MN up in North Branch.

I will 2nd Off we go rocketry, Gary is great to deal with and travels around to different launches also. If he does not have it he can order it.

29mm and 38mm are a great L1 starting point pending your building skill and field/flight profile.

DMS is a great way to get your feet wet, try some different motors and see what you like. There are so many aspects to the hobby, it's a journey not a race or destination.

The RMS from Aerotech, CTI, Loki will have a higher initial investment and a search on the forum will bring up threads discussing it.

I find all the reloads easy to assemble with some prep, planning and instructions.

I have a mix of cases: 24mm Aerotech and CTI; 29mm CTI and research snap ring; 38mm Aerotech,CTI, Loki; 54mm Aerotech, Loki; 75mm Aerotech, Ellis snap ring; 98mm Aerotech.

 

[SolarYellow]

I have done a bunch of sim work and ended up planning around CTI 38mm hardware for L1 and L2. Some of the rockets I want to work with are a little shorter and the 38mm stuff isn't as long as the 29mm stuff of similar impulse, so it packages better in the more efficient, shorter airframes. We have a motor guy who attends launches, so HAZ is not a problem.

 

[teepot]

I considered RMS. But we only fly 10 times a year. I sometimes fly at home. I just don't fly enough to go the RMS route. With BMS just around the corner I don't pay HazMat.

 

[KenECoyote]

Some additional points for thought that aren't mentioned as often...

• RMS can cost you more money than DMS if you lose or cato the rocket and casing before savings are realized.
• RMS can be more error prone due to added possibility of user assembly error.
• You'll need to clean the RMS casings after each use, which I think most consider a chore.
• RMS does require more time to prep (mentioned above), so consider that added with the above points when deciding if it is saving you money vs less time and more convenience.
• Learning RMS is a good skill to have and another thing to add to your rocketry resume to impress your LP friends.
• I believe RMS allows more flexibility in choice of motors.
• FWIW RMS may be more ecological since you're not throwing away a used plastic motor casing afterwards... some which can be pretty large.

 

[Steve Shannon]

There’s some great advice in some of the previous posts and I don’t disagree with anyone on why a particular case is right for them.
I always tell people to build and fly a few rockets using borrowed cases before making a decision to buy any cases. In my experience there’s always someone who’s willing to loan you a case. The usual conditions apply: if you lose it or break it you replace it. I borrowed cases when I was getting started. Every one of my certification flights was on borrowed hardware. Now I’m one of the people at a launch loaning cases to others.
This way your own experience will lead you to the right decision for yourself.
Another advantage to waiting is that there’s always someone getting out of the hobby and if you surround yourself with other rocket people you’ll have opportunities to buy previously owned cases.

 

[boatgeek]

In addition to the other great advice above, consider a few other things:

Are you in a financial position to order a year's worth of motors at once? If you are, then the $35 hazmat shipping fee is spread over 15-20 motors and becomes nearly a non-issue.

In the motor diameter/impulse ranges you're looking at, check out the DMS and RMS options. Some propellants (eg green or smoky) are more or less only available in RMS. If you want to fly green or smoky motors, that's your answer. If you're happy flying the various blue/white/sparky motors that are available in DMS, it's not so much of an issue.

 

[Tech 68]

There’s some great advice in some of the previous posts and I don’t disagree with anyone on why a particular case is right for them.
I always tell people to build and fly a few rockets using borrowed cases before making a decision to buy any cases. In my experience there’s always someone who’s willing to loan you a case. The usual conditions apply: if you lose it or break it you replace it. I borrowed cases when I was getting started. Every one of my certification flights was on borrowed hardware. Now I’m one of the people at a launch loaning cases to others.
This way your own experience will lead you to the right decision for yourself.
Another advantage to waiting is that there’s always someone getting out of the hobby and if you surround yourself with other rocket people you’ll have opportunities to buy previously owned cases.

My old Prefecture had "loaner" cases available.

 

[sharkbait]

In addition to the other great advice above, consider a few other things:

Are you in a financial position to order a year's worth of motors at once? If you are, then the $35 hazmat shipping fee is spread over 15-20 motors and becomes nearly a non-issue.

In the motor diameter/impulse ranges you're looking at, check out the DMS and RMS options. Some propellants (eg green or smoky) are more or less only available in RMS. If you want to fly green or smoky motors, that's your answer. If you're happy flying the various blue/white/sparky motors that are available in DMS, it's not so much of an issue.

I do 15-20 motors per launch

 

[Wrightme43]

Thank you all.