D40

[Rocketjunkie]

Here's a pic of my 13 mm D40 motor and what's in it.
Top to bottom:
case
liner tube
closures, nozzle, O-rings
Propellant, 4 grains and a solid delay grain
The rocket I usually fly these in since Gnomes are gone. It only weighs 4 grams.

 

[Rocketjunkie]

This is the thrust curve

 

[n3tjm]

Wow... that is a very nice motor . I always wondered if a 13mm reloadable was doable.... now I know .

 

[rstaff3]

Yes this is awesome. That's a lot of oomph for a D

 

[Austin]

OMG...that thing is huge!!!

Carl

 

[Neil]

No its not! Its 13MM for cryin out loud, thats almost as small as they make em! Though it is pretty long.... I couldent load the thrust curve. is this something you made yourself or is there someplace I can buy this thing???

 

[n3tjm]

Originally posted by Neil
No its not! Its 13MM for cryin out loud, thats almost as small as they make em!

Neil... Think about it... D40... D40... D40

 

[powderburner]

Originally posted by Rocketjunkie
The rocket I usually fly these in since Gnomes are gone.

I can't think very many 13mm (or 18mm) rockets that would NOT head for Mars if powered by a little monster like this.

Where in the heck did you find this motor? Is this a home-made job?

 

[Neil]

D40... Got it. High thrust. short burn. physically SMALL. BIG thrust compared to other motors that size. It still aint an N2000! *THAT* is big!

 

[Rocketjunkie]

Originally posted by powderburner
I can't think very many 13mm (or 18mm) rockets that would NOT head for Mars if powered by a little monster like this.

Where in the heck did you find this motor? Is this a home-made job?

These are EX motors that I've been making for a couple years. I also make C20's, 2" shorter. A Gnome will go 1000 mph on a D40 and survive once, usually loses the fins the second flight.

 

[Neil]

How much do you want for a dozen of those puppies and a case? are you planning on selling????

 

[Rocketjunkie]

Originally posted by Neil
How much do you want for a dozen of those puppies and a case? are you planning on selling????

Sorry, there is no way I can ship propellant. Also, it's an interesting area whether I can sell them legally. If they were over 62g, I know I can't since I don't have a LEMP. Under 62g ???
I only have 1 D40 case now but lots of C20 cases and nozzles. I have sold cases and nozzles in the past along with instructions on how to make the propellant. It will be a while before I get the CNC lathe out of storage and set up to make more cases.

 

[rstaff3]

Geesh rocketjunkie, you have WAAAAAY too many cool toys if you keep your CNC lathe in storage

 

[Neil]

no kidding! Everyone has more powertools than I do! waaaaaaaah! A CNC lathe? how did you score *THAT*? theres gotta be a story here...

 

[Austin]

Man, I just realized...you have any idea how fast it burns...jeez!

Carl

 

[Neil]

Im guessing about .5 seconds... Why? My computer wont load te thrust curve...

 

[rstaff3]

Imagine a Fatboy on 12 of 'em! I guess rocketjunkie only claims to have used C20s tho.

 

[WiK]

Whats the point in that being a reload? You put it in any small 13mm rocket and you wont see it again!

 

[rstaff3]

Practice on the CNC before you make your P class casing? Actually, I vote for the 'cool factor', which in this case is off the charts IMHO.

 

[Rocketjunkie]

Originally posted by WiK
Whats the point in that being a reload? You put it in any small 13mm rocket and you wont see it again!

Actually, I get them back almost half of the time

 

[Rocketjunkie]

Originally posted by rstaff3
Practice on the CNC before you make your P class casing? Actually, I vote for the 'cool factor', which in this case is off the charts IMHO.

I kept the CNC lathe when I sold the rest of the business. The 13 mm motors are reloads since I had the materials (and CNC lathe) on hand. The P motor is a fiberglass cased SU motor, intended for altitude.

Here's some pics:
https://www.tripolisc.org/modules/xgallery/view_album.php?set_albumName=album07&page=2

 

[n3tjm]

Originally posted by WiK
Whats the point in that being a reload? You put it in any small 13mm rocket and you wont see it again!

Think about it... a Mosquito warps off the pad with a A10-0T...

A stretched mosquito will enter warp on a D40...

Does the motor have a delay or ejection charge?

 

[Rocketjunkie]

Originally posted by n3tjm
Does the motor have a delay or ejection charge?

Yes. As made, the delay is 13 seconds and may be cut down as needed. (Cutting the propellant end of the delay grain adds 1 N-s for every 3 seconds the delay is shortened.)

 

[edwardw]

That is an awesome D - I have a J motor that is kind of the same, it is a J 1383, only burns for about .7 seconds. If it burned any longer it wouldn't be a J Nice work...

 

[Neil]

Holy cow! what diameter is that J? Thats quite the thing.... How does it fly?

 

[edwardw]

It is 1" diameter. Flies great! Go to my site and go under Engines - J1383

 

[Neil]

Someone needs to buy me a burial plot... I cant take it! 1" diameter!? as in 24MM!? a J!? 24" long, but still...

Wait a sec! I just looked at your rockets... I bet you get this alot... WHY DO YOU HAVE CARDBOARD FINS ON THOSE THINGS!? You fly these things on *WHAT* motors!? Js? Ls?

Now *THAT* is rockets on a budget!

 

[edwardw]

Did you check the flights - they fly alright too The Zerrubabbel flights are the best.

Edward

 

[Neil]

OK. You got me here. You fly Js with cardboard fins? and they WORK? Coooooooolllll..... Im not about to start trying this yet.... Still sounds just a *little* dangerous to me...

 

[Johnnie]

At the Nov launch in O'Burg, I believe I saw the smaller 18mm version that you had passed on to Jim Mitchell...He said he was going to play with it a little, I think I'll drop him a line and see if he might duplicate it a couple of times. Kinda resembles Stuart Leslie's 1/2" candy reloadable...