# Now that I am Level 1 Cert should I switch to reloadable motors instead of DMS?

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#### ridnharley

##### Active Member
Could I save money going with reloadable motors or are their disadvantages?
Stick with DMS or not?
Going for Level 2 Cert soon.

#### o1d_dude

##### 'I battle gravity'
TRF Supporter
I am L2 and prefer DMS whenever possible so there’s that.

If you launch regularly, have short lines at the pad, and easy retrievals, go for the RMS reloads.

I have none of those so the DMS allows me to get two, sometimes three flights at a launch.

#### DMehalko

##### Well-Known Member
Do you want to save money and enjoy assembling things? - RMS
Do you like spending more and want instant gratification? - DMS

##### Well-Known Member
Branch out. Look at RMS, CTI, Loki... Lots of options and lots of reasons to try different things.

#### Nytrunner

##### Pop lugs, not drugs
Another benefit of the reloadables is you can get more of a variety of propellant types in different impulse loads

#### OverTheTop

##### Well-Known Member
Choose whatever makes sense for you . Personally I only fly reloadables in HPR due to the fuels available.

#### Dudeman247.

##### Active Member
I fly both but more reloadable. There is more cost up front with buying motor casings as you probably know.

#### Walter Longburn

##### Well-Known Member
Whether or not you save money with RMS depends on how much you fly the case.

#### Dudeman247.

##### Active Member
A fellow forum member JLebow worked out this graph.

#### Steve Shannon

##### Well-Known Member
TRF Supporter
Borrow a case and try using a reload. If you enjoy it, then great. I enjoy assembling reloadables, but when I started DMS wasn’t available. It’s whatever you enjoy.

#### Walter Longburn

##### Well-Known Member
It’s whatever you enjoy.
+1
This hobby isn't really about saving money.

#### Theory

##### Well-Known Member
This hobby isn't really about saving money.
about as true as a statement can be!!!

##### Well-Known Member
one thing about having hardware, if you ever want to get into making your own research motors at least you'll have motor hardware and assembly experience.

#### AeroTech

It’s nice having options. There are applications for both.

#### BABAR

##### Builds Rockets for NASA
TRF Supporter
I’m L-0, but I am surprised no one has pointed out that it certainly must hurt more in the wallet if you lose a rocket with a reloadable motor case, or if a flight ends reaaaaalllly badly......... I guess with high power rockets and all their telemetry you don’t lose them as often?

#### tsmith1315

##### Well-Known Member
I can confirm that ballistic return from 8k' will not damage 54mm AT hardware. Even when nothing else survives but the fins.

#### Mike Haberer

TRF Supporter

Last edited:

##### Well-Known Member
TRF Supporter
Could I save money going with reloadable motors or are their disadvantages?
Stick with DMS or not?
Going for Level 2 Cert soon.
Nothing wrong with flying either RMS or DMS motors, and your decision should NOT be based on the L2 flight timing.

As you start planning ahead, you will figure out what are the most likely motors sizes and diameters that you will be building and flying (e.g.: 29mm G's & H's, or 38mm H's & I's, or 54mm J's & K's). Then collect the reload prices for both, and you will figure out that you will be financially better off buying a RMS case to go for the types of motors you will be flying more than 2-3 times.
Even then, you may prefer the simplicity, and lower risk of financial hit when flying out-of-sight-high with DMS motors, and there is nothing wrong with that.

A fellow forum member JLebow worked out this graph.
There is something very wrong with these graphs - RMS vs. DMS cost break-even is usually around 2-3 flights, not 10-25 !

#### Flyfalcons

##### Well-Known Member
I like to fly both, depending on selection and cost difference. One huge benefit to DMS over reloads is prep time on the DMS is minimal, and clean up time is zero.

And yes @afadeev, depending on the motor used, the the DMS version may be only minimally more expensive than the reload, resulting in a considerable number of flights to tip the economic argument towards reloads. On Wildman, the J350W is 73.99 vs the J270W and J435WS at 79.99. If you can find a 38/720 full motor hardware for twelve dollars then let us know.

#### Theory

##### Well-Known Member

Also, reloads give the end user ultimate control over the assembly of the motor.

the only motor related failure that I’ve experienced in the last few years was a SU motor

#### Buckeye

##### Well-Known Member
There is something wrong with the graphs, but the answer is not 2 or 3 as the crossover point!

From Wildman: the J350W is 73.99 vs the J270W and J435WS at 79.99. 38/720 full motor hardware is $130 (or$104). By my math, the cross over is 22 (or 18) flights, a far cry from 35.

Still, 22 (or 18) flights is a sobering high number to justify hardware purchases. The hardware ROI was much better years ago, I think. More DMS options are becoming available these days. If I was just starting out, I would focus on DMS for a while.

#### Ez2cDave

##### Well-Known Member
TRF Supporter
I enjoy assembling reloadables, but when I started DMS wasn’t available.
Back when I started, Single-Use motors was all there were . . .

Dave F.

#### Theory

##### Well-Known Member
recommend having fun and not justifying purchases. This is a hobby not a job or an investment

#### jimzcatz

##### Boss, Carolina Rocket Mafia
if you indeed seek opinions,mine is you should have started with reloads.

#### John Kemker

##### Well-Known Member
TRF Supporter
So, not disagreeing with you, but let me give an alternate perspective:

Since the casings are not cheap, I tend to take more care to ensure that I get the rocket back, at least the casing portion of it. Therefore, the concern about "there go your meager savings" becomes a moot point.

I will disagree with the Cesaroni decision: Higher costs due to HazMat fees for the 38mm reloads, as opposed to the non-HazMat fees of Loki or even AT reloads in that size. Cesaroni just doesn't make economic sense unless you're always buying on the field. Even then, you're paying for *someone's* HazMat shipping, even if it's the dealer's. Cesaroni costs become comparable once you get past 38mm, as everything above 38mm requires HazMat, no matter who manufactured it.

Some of us flew back when reloads were the main game for the average flyer. Sure, we'd fly the occasional H125, I65 or K250, but the costs compared to buying reloads for your hardware were prohibitive. Evidently, those costs have dropped to meet the market demands. (Or, reload costs have risen, take you pick.) The main reason you flew single-use was because the particular thrust profile you were looking for didn't exist in a reload. (Had a K125 98mm SU that I was going to fly in a minimum diameter rocket with a Nike-style fiberglass fin can and about the size of an EZI-65. Project was on the back burner, then lost it in the divorce. /sigh Ain't nobody to blame buy myself.)

Getting back into the hobby, I chose Loki because I prefer the snap-ring style hardware and the 38mm reloads are mostly non-HazMat shippable.

#### Ez2cDave

##### Well-Known Member
TRF Supporter
Could I save money going with reloadable motors or are their disadvantages?
Stick with DMS or not?
Going for Level 2 Cert soon.
A couple of quick questions :

(1) What is your monthly budget for Rocketry ?

(2) How often do you plan on flying HPR rockets ?

(3) For you , personally, are there any advantages to DMS over Reloads, considering there are a larger number of re-loadable motors to choose from ?

Dave F.

#### OverTheTop

##### Well-Known Member
I’m L-0, but I am surprised no one has pointed out that it certainly must hurt more in the wallet if you lose a rocket with a reloadable motor case, or if a flight ends reaaaaalllly badly......... I guess with high power rockets and all their telemetry you don’t lose them as often?
Yes, that happens occasionally. I have lost two significant rockets over the years. About \$2k in hardware total. Running DMS would not have saved me the majority of the cost.

#### voltzwgn

##### New Member
Another factor no one has mentioned is the waste factor.......... I'm becoming more and more aware of the amount of plastic and trash that I generate. Just got my L1 last weekend and used DMS motors more for the ease (isn't this part of the reason for we generate so much trash?) than anything else. But certainly looking at RMS in the future, I may be mistaken but it seems there is less trash generated by the RMS motor? Hopefully someone will correct me if this is a mistaken assumption.

#### Dustin Lobner

##### Well-Known Member
TRF Supporter
I did L1 and L2 on DMS and will be doing L3 on a DMS as well. When I look at the cost delta of DMS vrs. hardware + reload, it's hard for me to justify the hardware for how little flying I'm realistically able to do. If I end up buying hardware sometime, it'll likely be for experimental things.

Great thing is that we have choices!

#### Eljay

##### Well-Known Member
There's nothing wrong with using both. I show up at a launch with pre-loaded RMS cases and usually a few DMS motors as well for my "stretch goals" that I'll only do if the weather is good, lines are short etc.