Would you like to see a 24mm reloadable G

The Rocketry Forum

Help Support The Rocketry Forum:

Dunno

  • 1

  • 2

  • 3

  • 4

  • 1

  • 2

  • 3

  • 4


Results are only viewable after voting.

Karl

Well-Known Member
TRF Supporter
Joined
Jun 30, 2010
Messages
2,460
Reaction score
26
Could someone tell me if a Ellis Mountain G37-6 could lift a 19oz rocket?
Cheers
Karl
 

rstaff3

Oddroc-eteer
Joined
Jan 18, 2009
Messages
11,759
Reaction score
14
The delay depends on the rocket, but the thrust to weight ratio is fine.
 

stevecarr

Well-Known Member
Joined
Apr 2, 2004
Messages
203
Reaction score
0
What he said.
Lance might have some if he's there this weekend Loopy.
 

loopy

Well-Known Member
Joined
Dec 13, 2009
Messages
4,586
Reaction score
2
Originally posted by stevecarr
What he said.
Lance might have some if he's there this weekend Loopy.
Yeah, I'll have to check with him next time I'm at a launch. Weather doesn't look to promising this weekend, and my bank account is even less promising...:( Oh well - someday! :D

Loopy
 

Johnnie

Well-Known Member
Joined
Dec 31, 2002
Messages
4,292
Reaction score
0
A 2-grain 24mm G would sweet...especially in Black Jack propellant...maybe a 3 second burn like the lost G33(?)

I voted yes...

Johnnie
 

Daedalus

Well-Known Member
Joined
Jan 22, 2009
Messages
549
Reaction score
0
24mm G reload would = a lot of lost reload casings.
Perhaps not too many lost casings - I would be using them in clusters. Pyrophoria would really shift with some 24mm slow Gs replacing the D12s around a central I motor :cool: Mind you, a loss of this rocket would then be seriously expensive
 

Initiator001

Well-Known Member
Joined
Jan 19, 2009
Messages
2,915
Reaction score
173
I believe that there would be a very small market for such a casing and reloads for it.

It would have a very limited, if any, use in any kits from the major manufacturers (Estes, Quest, AeroTech).

The diversion of resources by AeroTech to produce a product with limited sales potential would seem to me be an effort with little or no financial return.

A nice dream, however. :D
 

Art Upton

Well-Known Member
Joined
Jan 23, 2009
Messages
1,937
Reaction score
42
At NARAM-47 Gary showed a 24mm Two grain case he was testing and looking to market some day. I asked him a few of quesitons about it.

Since he has not yet released it to market, I had a machine shop make me one just like it.

I won't be able to fly it anywhere but an Indi launch, but it's still kewl™

Someday we may see this come to market.
 

Johnnie

Well-Known Member
Joined
Dec 31, 2002
Messages
4,292
Reaction score
0
At NARAM-47 Gary showed a 24mm Two grain case he was testing and looking to market some day. I asked him a few of quesitons about it.

Since he has not yet released it to market, I had a machine shop make me one just like it.

I won't be able to fly it anywhere but an Indi launch, but it's still kewl™

Someday we may see this come to market.

Nice! Did he elude as to what classification it might run at? How about yours? What do you hope your to be?

Johnnie
 

Rick Lindsey

Well-Known Member
Joined
Nov 27, 2006
Messages
704
Reaction score
0
A 2-grain 24mm G would sweet...especially in Black Jack propellant...maybe a 3 second burn like the lost G33(?)

I voted yes...

Johnnie

Unless it involves an end or moon burning slug, you're not likely to get 3 seconds out of a 24mm blackjack... with the bates grain configuration you're likely to find that within a given propellant, the burn time is proportional to the diameter. That's why we need a 62.5g 38/120 blackjack load! (which would probably only have 90ns, but that''s okay, we'd love it anyways!)

-Rick
 

n3tjm

Papa Elf
Joined
Jan 21, 2009
Messages
7,459
Reaction score
382
Location
Penns Creek, PA
Unless it involves an end or moon burning slug, you're not likely to get 3 seconds out of a 24mm blackjack... with the bates grain configuration you're likely to find that within a given propellant, the burn time is proportional to the diameter. That's why we need a 62.5g 38/120 blackjack load! (which would probably only have 90ns, but that''s okay, we'd love it anyways!)

-Rick
Why Not? E11 and F12 are 24mm Blackjacks and they have a three second burn :D
 

Tominator 2

Well-Known Member
Joined
Jan 23, 2009
Messages
296
Reaction score
0
That would be sweet! Maybe I should try a E15 in my 24 min dia!:D:D
 

uncle_vanya

Well-Known Member
Joined
Jul 5, 2006
Messages
1,988
Reaction score
0
At NARAM-47 Gary showed a 24mm Two grain case he was testing and looking to market some day. I asked him a few of quesitons about it.

Since he has not yet released it to market, I had a machine shop make me one just like it.

I won't be able to fly it anywhere but an Indi launch, but it's still kewl™

Someday we may see this come to market.
Art - what do you use for propellant? Do you mix your own or is there a way to reuse existing reload kits in a way that makes a 24mm G out of parts from other kits.
 

WillCarney

Well-Known Member
Joined
May 13, 2009
Messages
852
Reaction score
0
I have already tested several 24 mm motors. My put file site shows
an E-50 and F-71 24mm test. I also have tested a G 24 mm (video not
available yet). These are true EX cases. 6061 T6 cases with closures and
graphite nozzles.

https://www.putfile.com/willcarney

William
 

Lee Reep

Well-Known Member
Joined
Mar 22, 2002
Messages
518
Reaction score
0
My Estes Phoenix is SCREAMING for a 24mm reload!!! (It's a pun...get it?) Anyway - it's pretty heavy, and I really can't get it much over 900 feet with the available 24mm loads.

Loopy
I've flown more 24mm reloads in an Estes Phoenix than almost any other single rocket. A larger F, or small G would be nice. The Phoenix I built was basically stock, with "spokes" of basswood on the paper centering rings, spanning from motor tube to body tube. I also CA'd the fins to toughen them.

I had been away from high-to-mid power for awhile, and did not realize than Aerotech came out with a G71R Redline reload for the 29/40-120 casing. I bought several at a launch in October, but have not flown them. I'd like to see some Redline reloads for the 24/40 casing.
 

bobkrech

Well-Known Member
Joined
Jan 20, 2009
Messages
8,353
Reaction score
37
:D
It would be nice if it was the same size as an Estes E9.
It can't be done. It's simply not possible to fit 80+ NS of propellant in an Estes E9 size casing with dimensions of 24 mm diameter x 95 mm long.

The new 29 mm AT G80 has a total impulse of 137 NS and casing dimensions of 29 mm diameter and 128 mm long. The last 24 mm AT G motor was the AT G55 with a total impulse of 125 NS with casing dimensions of 24 mm x 177 mm long. The old 24 mm AT F72 had a total impulse of 80 NS with casing dimensions of 24 mm x 125 mm long.

Bob
 

BayouRat

Well-Known Member
Joined
Feb 17, 2009
Messages
959
Reaction score
56
Location
Luling, LA
It can't be done. It's simply not possible to fit 80+ NS of propellant in an Estes E9 size casing with dimensions of 24 mm diameter x 95 mm long.

The new 29 mm AT G80 has a total impulse of 137 NS and casing dimensions of 29 mm diameter and 128 mm long. The last 24 mm AT G motor was the AT G55 with a total impulse of 125 NS with casing dimensions of 24 mm x 177 mm long. The old 24 mm AT F72 had a total impulse of 80 NS with casing dimensions of 24 mm x 125 mm long.

Bob
This will be a reloadable and not a single use. I'll have to crunch some numbers to see what I come up with. They have three F motors in the 24mm D size reloadable case. I am sure it is do-able. But can it be done reliably, safely, and consistently.
 

bobkrech

Well-Known Member
Joined
Jan 20, 2009
Messages
8,353
Reaction score
37
This will be a reloadable and not a single use. I'll have to crunch some numbers to see what I come up with. They have three F motors in the 24mm D size reloadable case. I am sure it is do-able. But can it be done reliably, safely, and consistently.
There won't be a significant length difference between a SU or Reloadable 24 mm casing.

The assembly drawing for the 50 NS AT F39 is available here. https://www.aerotech-rocketry.com/c...s_assy_dwgs/24mm_mr_rms/24-40_f39-9t_assy.pdf and the casing drawing is here https://www.aerotech-rocketry.com/c...ech_rms_ext_dim_dwgs/24mm_mr_rms/mr_24-40.pdf

A single 50 NS F39 propellant grain is 2.051" long, and the 24/40 casing length is 2.718" inches long. The new 24 mm 2-grain casing tube would have to be lengthened by 2.051" to make a 4.77" long motor casing tube for a 2-grain 100 NS G motor, and by 4.102" to make a 6.82" motor casing tube for a 3 grain 150 NS G motor.

The length of the a 24/40 motor 3.828" (97 mm) from the thrust ring to the ejection charge, so the length of the proposed 2-grain 24/80 motor would be 5.88" (149 mm), and the length of the proposed 3-grain 24/120 motor would be 7.93" (201 mm).

Bob
 

n3tjm

Papa Elf
Joined
Jan 21, 2009
Messages
7,459
Reaction score
382
Location
Penns Creek, PA
I think its is possible to make a 80 n/s motor Estes E size... only problem is you'd be running the motor at such a high pressure that reliability would be an issue (would be extremely loud too ;)).
 

BayouRat

Well-Known Member
Joined
Feb 17, 2009
Messages
959
Reaction score
56
Location
Luling, LA
There won't be a significant length difference between a SU or Reloadable 24 mm casing.

The assembly drawing for the 50 NS AT F39 is available here. https://www.aerotech-rocketry.com/c...s_assy_dwgs/24mm_mr_rms/24-40_f39-9t_assy.pdf and the casing drawing is here https://www.aerotech-rocketry.com/c...ech_rms_ext_dim_dwgs/24mm_mr_rms/mr_24-40.pdf

A single 50 NS F39 propellant grain is 2.051" long, and the 24/40 casing length is 2.718" inches long. The new 24 mm 2-grain casing tube would have to be lengthened by 2.051" to make a 4.77" long motor casing tube for a 2-grain 100 NS G motor, and by 4.102" to make a 6.82" motor casing tube for a 3 grain 150 NS G motor.

The length of the a 24/40 motor 3.828" (97 mm) from the thrust ring to the ejection charge, so the length of the proposed 2-grain 24/80 motor would be 5.88" (149 mm), and the length of the proposed 3-grain 24/120 motor would be 7.93" (201 mm).

Bob
My point about the reloadable is that you can ramp up the KN in an aluminum case to achieve higher performance from the same amount of propellant. That's why single use motors are only E and reloadables in the same Estes 24mm D size can be an F.<O:p</O:p
:D<O:p></O:p>
 

Initiator001

Well-Known Member
Joined
Jan 19, 2009
Messages
2,915
Reaction score
173
My point about the reloadable is that you can ramp up the KN in an aluminum case to achieve higher performance from the same amount of propellant. That's why single use motors are only E and reloadables in the same Estes 24mm D size can be an F.<O:p</O:p
:D<O:p></O:p>
Years ago, AeroTech made a SU 24mm x 70mm F9 motor. It had around 50 NS performance. I flew one and it worked fine. It had a very small nozzle throat and a phenolic casing.

Gary Rosenfield told me that sales were poor so the F9 motor was dropped.
 

bobkrech

Well-Known Member
Joined
Jan 20, 2009
Messages
8,353
Reaction score
37
My point about the reloadable is that you can ramp up the KN in an aluminum case to achieve higher performance from the same amount of propellant. That's why single use motors are only E and reloadables in the same Estes 24mm D size can be an F.<O:p</O:p
:D<O:p></O:p>
Whenever you develop a new propellant composition, you must send it out to a DOT approved testing laboratory to be classified as a 1.4 low explosive before you can ship it. This costs ~$3,000 and when you add in your labor, it's going to cost probably ~$10,000 to develop a new propellant if things go smoothly and more if it doesn't, so you have to know that you will be able to retail at least several hundred thousand dollars of motors to make it worth your while, and it usually isn't.

That's why AT and the other motor manufacturers try to use common building blocks for their motors whenever possible to minimize manufacturing and inventory costs. For such a limited interest motor, AT would have to utilize an existing propellant and propellant size to make it economically feasible.

The design rules for such a proposed 24 mm motor using existing propellant grains would be to have a total propellant weight not exceeding 62.5 grams, an average thrust not exceeding 80 N and a total impulse not exceeding 160 NS so the new motor remains a model rocket motor. The current 24 mm propellant grains that would work are the 19 gram, 50 NS F24 and 22.7 gram, 50 NS F39 propellant grains. Two 2 grain 100 NS motors are possible: A G48 and a G78. Only one 3 grain motor is possible, a 150 NS G72 as the G117 is a high power motor due to average thrust and propellant weight.

The proposed 100 NS G48 would be similar but not as good as the old 125 NS SU G55 but the 150 NS G72 would be a great contest motor. Since the motor is a reloadable, there is a one time cost to the user of a longer motor casing tube but that's it. If enough folks ask for it, maybe Gary will consider making it.

Bob
 
Top