Excel Jr. & Stealth Jr. - rocsim files? engines?

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dr wogz

Fly caster
TRF Supporter
Feb 5, 2009
Reaction score
Land of Poutine!
Hi All,

Well, jsut got me 2 new rockets!
and these are my 'new to MPR' rockets.

I have recieved the Excel Jr. and the Stealth Jr.
(Gotta love Binderdesigns, excellent so far! packaging and instructions!)

A few quesitons / requests for you all:

What is your initial feelign over these two rockets?

Can someone point me towards rocsim files, to do 'flight tests'
Can someone recomend good engine / delay combos?

thanks all
I have flown the Ste. Jr. alot, love that rocket! I've had it up on G64-7 (work awesome on this rocket) and a G75. The 75 caused the shockcord to burn right about the attachment pint, and the fins can fell, the payload/ NC parachuted down.. She will be rebuilt though! I'd suggest something to protect the cord right at motor mount. Now I use a Kevlar sheath if I know I wouldn't be able to replace it...

Het I just got my stealth Jr today!! And I have a quick question. The instructions say that you have optional motor retainer do I need one?? Can I make my own?I am leaving this Saturday going to New Mexico to launch it so I don't really have time to order one.

Thanks rocketman 13
The Binder Design motor collars (retainers) are no longer available. You can friction fit the motor with masking tape or use Kaplow clips (blind nuts with screws & clips).

Or if you want to break the bank, you can go with a Slimline or Aero Pack retainer :eek: While *completely* overkill, these retainers ROCK!
You don't NEED one, but i'd suggest it, especially with reloadable motors. If you cant get one, you can just the friction fit method, but be sure it's in very good!
Thanks guys I am using single use motors so I am going to do the friction method. Thanks rocketman 13
I think the difference in cost by flying about 4-5 G reloads instead of single use pays for an Aeropack retainer. Just a thought...
Alright thanks for the thought. I will post pictures of it completed later. Rocketman 13
Also would it be ok to use an Estes motor mount if I cut off the lower hook and taped it to the motor tube to hold the engine in? Rocketman13
Uh, I'm pretty sure No, for a couple of reasons.

First, I don't think the hook would hold it. I really wouldn't go that route. Second, you probably would not want to. I've seen Black powder Estes motors come out with those, and I sure wouldn't risk reload hardware.

Really, I don't think you want too anyway. I'd say do the clips method explained earlier. I almost guarantee you'd regret the motor clip.

Just my opinion,

Picture of.... What do you think?? My completed Stealth Jr.!!

Hey guys,

thanks for the input.

I recently launched my Stealth Jr. on a G40W-7. One of the best / exciting flights I've had to date. period. And probablly one of teh highest too!! First flights are always fun!

While I try to find a reliable sopurse of these 'mid sized' engines (why are they sooo hard to find!!) let me tell you teh flight of my Stealth Jr.:

A beee-utiful Saturday, jsut a few weeks ago. Hot, Humid, not wind (well, a little, a breeze) and a milk crate full of rockets and engines.

My freind had his siter show up with a gaggle of kids.

With a slight breeze onteh ground, we positioned ourselves 'upwind', and gave teh launchrod a slight lean, as to not 'run forever' retrieving it.

Rocket was prepped, adn teh bnutton was pushed. Man, I love teh sound of the GXXW's throaty roar, and white smoke trail.

The Stealth Jr. leaped into the sky, and arced over nicely, as expected. The 'chute popped, and we watched it come down. Only it wasent; drifting towards us. It seems to be comming down, in a stright line. So, instead of running back to get it, we had to run forward to get it. It did land, jsut behind a tree line. Or shoudl I say, it found the l;ast tree on teh tree line. Kevin whippped up teh tree, and managed to yank it out.

we figured there was no wind above about 20 feet. What we felt as wind, was probably turbulence off trees & 'ground effects' and / or thermals.

The rest of the launches were pretty much straight up!
Cool! Glad to hear you got it back. As to your question about why the mid power engines are hard to find - the supplier (Aerotech) had a devastating explosion and fire a while back that completely shut them down for about a year or so. Only now is the pipeline starting to refill.

Cool, thanks for eh update..

I knoew they had an 'accident' but thought it was all taken care of.

Are there any other 'mid power' manufacturers? Or do Aerotech have teh 'market'?
Aerotech pretty much has the market on Mid power. It's getting pretty good for mid power, selection should be back to normal in a few months, it seems. Granted, I don't know what selection may be like in Canada, which may make it more complicated. It also seems that 29mm reloads are more prevalent than the single use motors.

Well, good to hear. I do hope they get back to teh level they once were.

As for 'in Canada', crossing that 'line in the sand' requires a bunch of paper work, and $$$ that teh governement requires you pay them for the priviledge. i don't expect, nor do my local suppliers, to see any Aerotech engines in the near, or not too far future. Next year maybe, if they decide to carry them anymore..

Trying to find 29mm reloads as well. Dunno who to turn to, nor where to get the 'inserts'..

It would seem that there are only about 5, or 10 mid and high power engine dealers this side of that line...