Sugar Motor Reloads

[edwardw]

Hey All,

After reading the "Home Come No Certified Sugar Motors" it has inspired me and one of my rocketry buds to look into it more seriously.

We currently are thinking about two options:

Manufacture our own casings and sell reloads for them

OR

Use existing Aerotech Hardware and make reloads.

For the first option:

We would create a line of casings and reloads ranging from G-I to start with. They would start out in the EX class and if we had enough response we might try and get them certified.

If we used Aerotech hardware we would also have them in the EX class of reloads. We also know that this would invalidate warranties from Aerotech, but most expire after a year.


I just wanted opinions and what people thought about the idea.


Edward

 

[MarkABrown]

Well, if they were EX class motors, only you would be able to fly them at TRA sanctioned launches. Only the manufacturer of the propellant is allowed to fly EX motors. You may have problems getting your venture off the ground if you have to depend on non-affiliated launches.

 

[n3tjm]

First things first... You need to get all permits, insurances, and equipment required to manufacture the rocket motors. Then you would need to get DOT EX numbers for each formulation of propellant, and then get them certified. I seriously doubt Sugar Motors would pass the DOT testing, so the $50K to $100K you spend gettig a legal company going may not be worth it to manufacture motors that are prone to so many problems.

 

[rstaff3]

I don't see why a sugar motor reload wouldn't be able to get an EX number. I may be incorrect, but I thought DOT tests ony catagorized the material as to its composition and hazardous properties, and they assigned the proper shipping status. I wouldn't think that the properties that make the sugar motors less desireable for us would affect the DOT process.

Like I said this is just the impression I have formed. I may be ignerint, but I kan lern.

PS Even if I'm correct, the other points brought up by Mark and N3TJM are still valid.

 

[n3tjm]

They would not survive the shock test... and they will show a sensitivity to moisture. Now we know that won't cause it to auto-ignite or anything... but they have to test that to prove it... more $$$ out of your pocket because each test costs $1000's of dollars.

 

[rstaff3]

I would think the shock test is intended to see if the material explodes, burns, etc. Would they really care if the grain cracked? They are testing for shipping safety. I would also doubt that it would matter if the material absorbs moisture unless it made its properties worse.

This doesn't change the fact that formal testing cost boatloads of $.

This whole isssue comes down to profitability IMHO.

 

[edwardw]

My partner is doing most of the business/legal side of things and he has mentioned to me all of the DOT EX numbers and such in passing, but he knows the details and I do not at the moment.

So far he has been flying the motors for his friends and that is how they became interested and where he is a lot of people said they would buy the motors.

The moisture sensitivity problem has pretty much been solved using some creative chemistry. I just pulled a grain out of a jar of water Saturday and it had been in there for a week and it was still good after toweling off and fired right up.

I agree that it comes down to profitability. I think the profit margin would be small, but it can be done.

He e-mailed me some numbers of start up costs and needless to say I was floored by the actual cost. Both of us would also like to see another type of propellant introduced and more options out there for the rocket community.

 

[rstaff3]

I for one would welcome another propellant option. Since I have the 38mm RMS casings, that would be good for me. If you get them legal to ship, I'd try one

 

[Johnnie]

What would be your fuel? I know with TRA EX launches, Sucrose based propellants are not allowed, only Sorbitol and Dextrose. I know you are not talking EX motors, you are leaning towards getting Candy certified, but I would keep that in mind when going for certs with TRA in the future...

boy, talk about your big melting pots
Commercially made Candy propellant could be a suprize hit if it worked out for ya...you will have to keep us posted.

What would be your estimated cost of an "M" reload?? $100?? L3 on the cheap

Good Luck!

 

[edwardw]

The fuel is sorbitol....Chosen over dextrose cause I can get it cheaper and melts lower...and is less hygroscopic. I haven't thought of what an M reload would cost...but right now it costs me $.75 a pound to make the propellant. That is just raw materials.

As for melting pot - yes, it is big. Right now I have a 5 gallon stainless steel pot that I use with a heating element I made. 5 gallons is a ton of propellant.


On another note - I'm not going for high performance on these reloads....the ISP is low on them usually 120-140. There are some really cool effects you can do though. Just last week I had a shuttle like launch with a 3 part grain. First it ignited an put off a ton of smoke for about 1/2 a second, then it started thrusting and took off. Then about 3/4 of the way into the burn the smoke turned pink and it accellerated even more. It was a prototype we created and it was wayyyyy cool. Also on some other forums there has been spark additive thoughts and that would be cool, but far into the future.


Johnnie - why isn't Sucrose allowed. I have read the rules but I don't get why it isn't included. Also I know Jimmy Yawn and Stuart Leslie made a proposale for the inclusion of sugar - do you know what happened to that?

 

[Johnnie]

Stuart and Jimmy set forth a proposal to the TRA board and gave a demo launch for them, in hopes of getting all three propellants approved for EX use. It was determined that Sucrose was touching on the dangerous side because of the elevated melting temps for the propellant. Either way, the proposal went through minus the inclusion of Sucrose, and the EX community has been a better place ever since.

I currently have a load designed and made for all of my Aerotech cases to include the 24/40; 29/40-120; 29/180 and 240 cases. These loads range from mid E- full G. In my 38mm cases, (non Aerotech) I have Baby I's through Baby J, and for my 76mm cases (non Aerotech as well) I have a full J thru Mid L designed out across 3 different case sizes.

On the SUGPRO list I would love to hear more about your 3-stage grain design. I have been following the "Sparky" talk as well...too errosive to the nozzle in my opinion, but what a cool night motor that would be...

 

[MarkABrown]

I think sucrose was excluded due to the flash temperature of the mixture. I could be wrong on that though. I think they thought that dextrose and sorbitol were safer to manufacture.

Regarding Doug's points above, I don't think the DOT would be a problem. What Dick said is correct. The DOT is only going to test for transport safety.

If you're committed to making the investment, I'd be very excited to see additional propellant selections available. I think your biggest hurdle is getting past the certification process. You'll have zero legal income at sanctioned launches until the reloads are certified. If you offer these for sale at non-affiliated launches, I'd be in the front of the line! I'm really anxious to hear how your venture proceeds. Keep us posted.

 

[rocwizard]

this was just posted on the XRAA's site: sparky sugar motors in action!

 

[Johnnie]

Rocwizard,

I got into a battle of the wits with a David Urbanek on the ROL EX forum over just such a subject...I stated that sugar motors would not run hot enough to get Ti to spark...(Egg on face) David was right all along. Imagine what that can do to a nozzle though.

...And that picture you posted rocks!!! Thanks for the post, it is now my background pic on my work computer.

 

[Manwithbeers]

Originally posted by Johnnierkt
Rocwizard,
<SNIP>I stated that sugar motors would not run hot enough to get Ti to spark...<SNIP

What is Ti?

 

[Johnnie]

The propellant is ladden with Titanium flakes for sparks (Ti)

 

[Johnnie]

So I'm on this Atkins diet see, cause I'm a chunk, and I get to looking at the ingrediants to a low carb Chocolat bar I ate last night, and I notice the one of the ingrediants: Mannitol...

FYI:

When the price domes down, this might be the Ingrediant needed for a Candy certified reload ($12.95 a pound): it boasts as being "NON-HYGROSCOPIC" (will not obsorb moisture), and is a member of the Sorbitol family of polyol substitute sweeteners...SWEET!!

 

[MarkABrown]

Originally posted by Johnnierkt
So I'm on this Atkins diet see, cause I'm a chunk, and I get to looking at the ingrediants to a low carb Chocolat bar I ate last night, and I notice the one of the ingrediants: Mannitol...

LOL

 

[wyldbill]

Originally posted by Johnnierkt
So I'm on this Atkins diet see, cause I'm a chunk, and I get to looking at the ingrediants to a low carb Chocolat bar I ate last night, and I notice the one of the ingrediants: Mannitol...
... a member of the Sorbitol family of polyol substitute sweeteners...SWEET!!

Another interesting fact about the sugar alcohols is that they're laxatives, Be careful how many you eat or the skidmark won't just be in your motormount...

 

[Johnnie]

Lurking cynic...dude thats wrong...bacon strips (skid marks) or not, my alcohol sugar motors move cleanly...

seriously though...non-hygroscopic!, and if it were as powerful as Sorbitol, half the battle might be over as far as keeping dry. Too expensive right now.

 

[AZ_Ron]

Originally posted by Johnnierkt
The propellant is ladden with Titanium flakes for sparks (Ti)

Hey Guys...just chiming in with a minor correction... the Titanium Norman Egolf and Kevin Patterson are using are lathe turnings, not flakes, although Norm grinds his up quite a bit before adding them to the propellant. Kevin uses them pretty much straight from the bag, although they have to be degreased to get all of the machining oil off of them.
Here's a pic of a rocket that I flew on one of Norms Sparky motors at the February XRAA launch...Here's the rocket...Me on the left, Norm on the right...

Ron

 

[AZ_Ron]

Here's the liftoff shot... a little slow, but you get the gist...

BTW, Norm sells titanium... there's an ad for it on the "For Sale" page of the AHPRA website... www.ahpra.org