RMS motors

I have recently delved into MPR, I only have 2 thus far (an Estes Ventris and an Estes NIKE Smoke) and Im sure the mid power fleet will grow. So I am contemplating RMS motors. My question(s) is this. What am I getting myself into and what do I need to know BEFORE purchasing any RMS hardware, propellant etc. Thank you much!

Welcome to MPR! there's really a lot of fun to be had wil mid power rockets that you can do without a high power certification. I think, personally, it's right in the middle of the "sweet spot" of the hobby.
So long as you don't lose the hardware, (from an Aerotech perspective) the RMS casing will pay for itself (versus single use) after just a couple flights. The 24/40 case can be bought here and will fit the D9W, D15T, E11J, E18W, E28T, F12J, F24W, and F39T reloads. Most of these can also be found at Hobbylinc. They do not ship Hazmat, and neither do their comparable single use motors. The F39T will probably lift the Ventris, but make sure it has a 5:1 thrust to weight ratio off the pad. You will also need an adapter to go from 24 to 29mm this case will also work well in any rocket designed for D or E motors, and really get them going! The other Aerotech MPR reload case is the 29/40-120. It will also save you money over the comparable single use motors very quickly. It is really a great case, with a wide variety of reloads: E16W, E23T, F22J, F40W, F52T, G53J, G76G, G64W, and the High Power HPG138NT which needs L1 certification. These reloads are also available from Hobbylinc, among other retailers. The "F" reloads (F22, F40, F52) for this case all ship Hazmat as would comparable Single Use motors. ($28.50 extra shipping charge :y because they have propellant grains with more than 30grams of propellant. Aerotech's line of Econojets are Single Use 'F' motors with less than 30 grams of propellant. They are notably less powerful than other F motors, but they don't need Hazmat. The 29/40-120 case will, without modification, fit into either the Ventris or the Nike Smoke (or any of the Estes PSII rockets). Neither of these motors are "difficult" to assemble. I had some help on my first time, and after that I was set to go! You can read and check over instructions here for various motors before actually ordering or opening the package. If you don't have Openrocket I would highly recommend installing it. Then you can get an idea of delay times for your given rocket on a given motor. I would also reccomend buying or borrowing an Aerotech Delay Drilling Tool which will allow you to adjust the ejection charge delay in 2 second increments. That about covers the basics, I'm sure others will chime in with their CTI recommendations (cheaper hardware, hazmat on all motors, more expensive reloads, easier assembly) more info can be found in this thread from a while back.
Great looking rockets by the way!!

Nate

Bigger rockets need bigger motors. It is a slippery slope. The bottom of which is defined by how much you are generally willing to spend per flight. You can get mid power flights in the G class for $10 - $30 per reload. You also have different manufacturer options such as Aerotech, Cesaroni or Loki (admittedly, I only fly the first two, and there are probably others, as well as research motors you mix and cast yourself)

I would start off by purchasing the 29/40-120 "hobby" Aerotech compatible case which will give you many mid power options. These reloads are easy to assemble and offer good value. Cesaroni are VERY easy to assemble and easy to clean. I fly both. From there you can move up to the 29mm High Power RMS system where the cases are (generally) sized based on the number of propellant grains (29/60, 29/100, 29/120, 29/180, 29/240, 29/360). The cases share common forward and real closures. Then you go up to larger diameter motors (38mm, 54mm, 75mm, etc.) for larger rockets.

29's are fun... and affordable.

More expensive to start, cheaper in the long run.

Not to open up an Aerotech vs. Cesaroni debate, but the OP needs to know.

Cesaroni Technology, Inc. (CTI) also makes reloadable motors. The casings are cheaper, but the reloads are more expensive. However, they are extremely easy to use (slide in the motor, screw in the aft closure--done). No washers, no O-rings, assembly. The only new concept might be drilling the delay grain.

For CTI casings, you specify the diameter and the maximum number of grains. You can use up to two spacers (additional cost) in place of grains, so that a 3-grain case can take 1-, 2-, or 3-grain reloads. And a 5-grain case can take 3-, 4- or 5-grain reloads. You get the idea.

Visit them here.

AT vs. CTI is a debate that will never end, but if you attend club launches with vendors, go with what they have so that you save shipping and HAZ fees.

Bat-mite said:

Not to open up an Aerotech vs. Cesaroni debate, but the OP needs to know.

Cesaroni Technology, Inc. (CTI) also makes reloadable motors. The casings are cheaper, but the reloads are more expensive. However, they are extremely easy to use (slide in the motor, screw in the aft closure--done). No washers, no O-rings, assembly. The only new concept might be drilling the delay grain.

For CTI casings, you specify the diameter and the maximum number of grains. You can use up to two spacers (additional cost) in place of grains, so that a 3-grain case can take 1-, 2-, or 3-grain reloads. And a 5-grain case can take 3-, 4- or 5-grain reloads. You get the idea.

Visit them here.

AT vs. CTI is a debate that will never end, but if you attend club launches with vendors, go with what they have so that you save shipping and HAZ fees.

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I would probably go with AT for cost reasons. Yeah CTI is easy to load but you pay twice as much for those reloads

Bat-mite said:

Not to open up an Aerotech vs. Cesaroni debate, but the OP needs to know.

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Hoping to keep this from becoming another one of "those" threads, let's just jump to the good advice; check with the vendor(s) you have showing up at your launches. Go with what is carried on the field and you'll same any HAZMAT fees and can get some good advice/guidance, too.

KennB said:

Hoping to keep this from becoming another one of "those" threads, let's just jump to the good advice; check with the vendor(s) you have showing up at your launches. Go with what is carried on the field and you'll same any HAZMAT fees and can get some good advice/guidance, too.

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The best advice!

wagondriver42 said:

I have recently delved into MPR, I only have 2 thus far (an Estes Ventris and an Estes NIKE Smoke) and Im sure the mid power fleet will grow. So I am contemplating RMS motors. My question(s) is this. What am I getting myself into and what do I need to know BEFORE purchasing any RMS hardware, propellant etc. Thank you much!

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Nate really nailed it! Beside the motor issue, you are climbing into slightly heavier models and the recovery systems for these are a blend of the LPR and HPR skills you will eventually encounter with these rockets. The 'rubber band' will no longer be sufficient to withstand the heat and deployment charges so you will need to become a little more familiar with the use of 'dog barf', Kevlar recovery harnesses and anchoring of the same, nomex protectors and nylon chutes. What are you getting yourself into? A lifetime of fun, excitement and occasionally, a chance to dance with the rocket gods on their home turf. Welcome to the smoke, brother! Keep us posted and remember-all us rocket ninnies love pictures. You have a great fleet going-keep it up! Calm skies and good chutes...

What fyrwrxz said

For mid power, I use only single use or the HP style Aerotech motor and of course Cesaroni 24 and 29 mm , I hate the hobby line casing of Aerotech

Some people report having issues with the estes retainers and RMS cases. The hobbyline (29 40-120) cases have smaller closures and fit fine.

I personally haven't had issues with it, and have flown 29/360 RMS cases in my rockets with estes retainers.

hobbyline on the left, RMS on the right


RMS on left, hobbyline on right



The 29/120 cases have two reloads, the G77 red and G79 white. Both are great motors. The 29/40-120 has a bunch of reloads as other have mentioned. (the G76G and G138T being two of my favorite motors to fly of any size) The cool thing about the RMS sets is that you can use those same closures on the 29/60,100,120,180,240, and 360 cases. And very very few of those motors need hazmat shipping. It gives a very wide selection of motors all the way up to a small I200W at a very low cost.

DizWolf said:

Some people report having issues with the estes retainers and RMS cases. The hobbyline (29 40-120) cases have smaller closures and fit fine.

I personally haven't had issues with it, and have flown 29/360 RMS cases in my rockets with estes retainers.

hobbyline on the left, RMS on the right

RMS on left, hobbyline on right

The 29/120 cases have two reloads, the G77 red and G79 white. Both are great motors. The 29/40-120 has a bunch of reloads as other have mentioned. (the G76G and G138T being two of my favorite motors to fly of any size) The cool thing about the RMS sets is that you can use those same closures on the 29/60,100,120,180,240, and 360 cases. And very very few of those motors need hazmat shipping. It gives a very wide selection of motors all the way up to a small I200W at a very low cost.

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I just ordered some ESTES retainers for my SUMO so it's nice to know that they will work with the HPR cases.

I am old school reload and reusable case flyer myself but there is something that has been left out here. Aerotech has been releasing single use motors that have no need for a case. The Economax line for example is a very nicely priced system for mid power. The new DMS line is high power single use motors with an adjustable delay. Eventually you will want to get some reload cases so you are not limited but I would first look into these single use motors and compare prices. Personally for mid power reusable motor I would start out with the 29/40-120 case. The G64 White Lightning is one of my very favorites.

AfterBurners said:

I just ordered some ESTES retainers for my SUMO so it's nice to know that they will work with the HPR cases.

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proof- bare, 29/40-120, 29/120


and as far as getting "too hot" for plastic, this is right after a pair of I200W's roasted the bottom of this rocket. It's unpainted on the bottom, that's all soot (and a bit of mud).

love the 29 40/120 hobbyline no hazmat G loads

hobbyline Aft Closure Wrench is a hand saver https://www.siriusrocketry.biz/ishop/aerotech-24-29mm-aft-closure-wrench-169.html

michigander said:

love the 29 40/120 hobbyline no hazmat G loads

hobbyline Aft Closure Wrench is a hand saver https://www.siriusrocketry.biz/ishop/aerotech-24-29mm-aft-closure-wrench-169.html

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+1 on the no hazmat!!


Jerome

JeromeK99 said:

+1 on the no hazmat!!


Jerome

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I remember the days when I said "hey look at all these no hazmat motors! I'm gonna get a full set of 29mm gear and only fly the no hazmat H and I motors! ".

Then along comes this man. We'll call him Tim. Psst. Hey kid.... This really cool fiberglass kit is only $100! What? That 54mm hole you can fit three pounds of AP in? Don't worry about that... It's not addictive....

WOW! holy plethora of information! Thank you very much folks! Anymore insight is always appreciated!

These posts are a good primer. I have spent many hours searching and reading post on TRF for specific topics. If you discover a system or technique that works, please share. For instance, I just discovered a great technique for making old or brittle (or VERY thin and delicate) waterslide decals workable. A single thin application of Pledge with Future Shine floor finish on the decal sheet before cutting and applying makes the decal thick enough to apply and re-position.

If you have a limited field and want to be able to limit the flight on windy days, etc., the HP-style AT cases don't have any smaller loads, you need the Hobbyline. I flew a good number of F40s and a F52 over the last year, in the 29/40-120, purchasing from the onsite vendor to save HAZMAT. However this case doesn't have any sub-HAZ F loads, only Es and Gs are non-HAZ. Small F's are avail. in Econojet SU motors and for the 24/40 and 24/60 cases. The 24 mm cases will fly your rockets. The F24 handles up to just over a pound and the F39 up to 1.5 lbs. Altitude in the 700's except for the F35. Great motor to have if you also have some smaller rockets to use it with.

On the down side, I got to go swimming last launch to retrieve my case along with the rest of the rocket, and spent a good while looking for an ejected casing once (found it). Loading and cleaning the cases, especially Aerotech, takes a lot of time. I usually bring motors pre-loaded to a launch and still shoot off a couple blackpowder motors as well. Also none of the Hobbyline non-certified loads are quite as powerful as the G80T single use/DMS. The only non-certified loads that are more powerful than the G80 require a baby-H case (these motors previously required certification anyway due to propellant weight).

I have the AT 24/40, AT 29/40-120, CTI Pro24-1G, CTI Pro24-3G, and the CTI Pro29-3G. All are good cases, all have something to offer. CTIs are easier to use and more $$ per flight. AT's take a little more work to load, but are less $$ per flight. All CTI motors require HAZ, but many smaller AT don't

The only instance where I would say that CTI beats AT hands down is if you intend to cluster motors. The pyrodex pellet in the top of a CTI motor makes ignition pretty much instant on; I've clustered CTIs and Estes motors with no problems.

For example: