How early ok to build engines?

[Steven88]

I am wondering how far ahead of a scheduled launch is it OK to put your reloads together for your motors? I know aerotech recommends not opening the road kit until ready for it, but it is nice to do it ahead of the launch if possible for myself. Is the main thing to keep them dry so they don’t take on moisture before the launch? Such as in a low humidity room?

 

[Jmhepworth]

I routinely put mine together weeks before a launch. And if for some reason I don’t launch one, I use it at the next opportunity.

 

[Conway Stevens]

I am wondering how far ahead of a scheduled launch is it OK to put your reloads together for your motors? I know aerotech recommends not opening the road kit until ready for it, but it is nice to do it ahead of the launch if possible for myself. Is the main thing to keep them dry so they don’t take on moisture before the launch? Such as in a low humidity room?

Some of the motors i fly require being bonded to the liner or the grains inhibited or both. I usually assemble a week ahead up to a month ahead of time. Once assembled i dont tighten the closures fully. This keeps compression of the orings from occurring. I also use masking tape and tape shut the nozzle hole or any other open end. I dont install any charges. The charges and tighten the closures can be done day of launch.

Ive had built motors stored correctly like this kept dry and room temp for over a year flown with no issues.

 

[jimzcatz]

I have motors loaded for years Never any issues.

 

[Handeman]

I usually prep everything but the motor a day or two before, including av-bays and DD charges, and do the motors at the site. None of my rockets are designed for one motor. I pick which motor to use at the launch based on lower and upper wind speeds, wind directions, cloud coverage and deck altitude, field conditions, etc. A 38mm MMT rocket might get a H128W in an adapter, or a J350W, depending on conditions on that day.

I have prepped motors and changed my mind. The assembled motor sat in my box till the next launch with the right conditions. That could be over a year later.

 

[pondman]

One of my rocket buddies has a couple of O3400s that made the round-trip to BALLS from Ohio 3 or 4 times. Lit and performed with zero issues.

 

[OzHybrid]

Seems to me, and I know nothing, that the transportation of a fully assembled motor may fall foul of the laws for road tranportation which is why they are usually made in smaller segments packed separately. But I'm not up on US regulations.

 

[NateB]

Seems to me, and I know nothing, that the transportation of a fully assembled motor may fall foul of the laws for road tranportation which is why they are usually made in smaller segments packed separately. But I'm not up on US regulations.

I'm not 100% positive how it pertains to rocket motors, but with fireworks an individual who has a BATFE permit for display fireworks can transport them (yes, even big ones) in their personal vehicle provided they are being used for personal purposes and not "in commerce". In this csse DOT laws do not apply, placards are not used, and hazmat certs are not required. The rules change when you are selling or transporting the product for a commercial or public display. It isn't a far stretch to think that an individual transporting a rocket motor would be a similar situation.

 

[Conway Stevens]

I'm not 100% positive how it pertains to rocket motors, but with fireworks an individual who has a BATFE permit for display fireworks can transport them (yes, even big ones) in their personal vehicle provided they are being used for personal purposes and not "in commerce". In this csse DOT laws do not apply, placards are not used, and hazmat certs are not required. The rules change when you are selling or transporting the product for a commercial or public display. It isn't a far stretch to think that an individual transporting a rocket motor would be a similar situation.

I would have to reread all the DOT info.... but It used to be required by BATFE that all were transported in correct storage containers. Such as a day box. They also had to be accounted for. But since the winning of the law suit and APCP is no longer regulated by them there are no requirements including the BATFE. But there is potential for DOT differences between state to state knowing each state laws can be the differences. As far as use by commerce vs personal. Dot does not apply to personal use of Comercial motors. Where it gets sketchy is research motors as they have not been tested and assigned a Dot number transportation could be considered illegal

 

[OzHybrid]

I would have to reread all the DOT info.... but It used to be required by BATFE that all were transported in correct storage containers. Such as a day box. They also had to be accounted for. But since the winning of the law suit and APCP is no longer regulated by them there are no requirements including the BATFE. But there is potential for DOT differences between state to state knowing each state laws can be the differences. As far as use by commerce vs personal. Dot does not apply to personal use of Comercial motors. Where it gets sketchy is research motors as they have not been tested and assigned a Dot number transportation could be considered illegal

Not passing the pub test I'm doing in my head. If there are freight transportation rules, I don't see how they would NOT apply just because you're driving in a personal vehicle. Then we run into the "is your vehicle insured transporting it" question. And if it's not, it's not legally on the road.
The BATF case was more about possession, purchase and use, not transport. But as stated, I'm not in the US.
I do think it needs legal clarification before someone gets on the wrong side of a roadside police check. It's a worm can waiting for the lid to be popped.

 

[OverTheTop]

Down here they need to be transported in the appropriately constructed day box. They also must not be in the passenger compartment. A few other requirements too.

 

[Neutronium95]

Not passing the pub test I'm doing in my head. If there are freight transportation rules, I don't see how they would NOT apply just because you're driving in a personal vehicle. Then we run into the "is your vehicle insured transporting it" question. And if it's not, it's not legally on the road.
The BATF case was more about possession, purchase and use, not transport. But as stated, I'm not in the US.
I do think it needs legal clarification before someone gets on the wrong side of a roadside police check. It's a worm can waiting for the lid to be popped.

From a legal standpoint, as far as I know in the US, the DOT is only allowed to regulate interstate commerce. A vendor transporting a reloadable motor fully assembled would possibly be in trouble, but the law doesn't apply to a regular person transporting a motor for personal use.

From a practical standpoint, the Aerotech L1000 is sold entirely preassembled, and the DOT has certified that configuration for transport. The Cesaroni O 25,000 was also sold fully assembled, and while it's in a different DOT class due to the propellant mass it is also allowed to be transported fully assembled.

 

[mrwalsh85]

What's the difference between assembling motors ahead of time, and keeping single use motors in your box for years at a time?

 

[mtnmanak]

I am not able to opine on the transport issue above (IANAL), but here is some reading about motor storage on this forum:

https://www.rocketryforum.com/threads/hpr-motor-storage.180545/
https://www.rocketryforum.com/threads/what-to-do-with-unflown-g-motor-composite-reloads.169081/
https://www.rocketryforum.com/threads/old-motors-safe-to-use.143102/
https://www.rocketryforum.com/threads/rebuilding-an-aerotech-rms-motor.136766/#post-1631958
Lot's of discussions in various places on the Aerotech thread:
https://www.rocketryforum.com/threads/aerotech-open-thread.125657/page-230#post-2471976
https://www.rocketryforum.com/threads/shelf-life.180309/#post-2443499
https://www.rocketryforum.com/threads/what-to-do-with-un-fired-aerotech-rms-motor.180136/
https://www.rocketryforum.com/threads/salvage-20-year-old-motors.180263/
There are probably more, but these were the ones that came up in the first few pages from a "motor storage" search.

 

[OzHybrid]

IANAL either. This is where Tripoli or NAR could provide an answer to the question so their members don't find themselves on the wrong side of IANAL opinions. Or the motor manufacturers should assist. It's their product. Not like they could say "We had no idea someone would do that"
I don't think there is any issue other than the transport of. I think it might come down to how they were dot-certified. Some were certified as flammable solids more recently. Some may have been certified under a different higher class but are now classified as flammable solids since the Batf case but have not been recertified as that for dot purposes.
I've seen Tripoli participate on this forum @Steve Shannon but not NAR. Just throwing it out there that it would be nice to hear from their board occasionally..

 

[Steve Shannon]

Seems to me, and I know nothing, that the transportation of a fully assembled motor may fall foul of the laws for road tranportation which is why they are usually made in smaller segments packed separately. But I'm not up on US regulations.

That would definitely affect the ability to ship it via a commercial carrier, but as far as I know the end user can assemble a motor and transport it in a private vehicle. Of course have no igniters in motors; that would just be stupid. For years folks have been assembling large motors before launches and then bringing them to the launch.

 

[Tractionengines]

Ones that require grain bonding or Epoxy assembly, should have 5-7 days for the Cure Process to reach maximum strength.

All Epoxies, and most glues, while "set" in 5, 15, 30 minutes, or 2, 4, 24 hours... take days for the "cure process" to finish.

 

[techrat]

Down here they need to be transported in the appropriately constructed day box. They also must not be in the passenger compartment. A few other requirements too.

How the heck does that work if you drive a hatchback??

 

[SolarYellow]

How the heck does that work if you drive a hatchback??

They don't drive hatchbacks in Australia.

https://upload.wikimedia.org/wikipe...Ute_(VF_MY14)_SV6_utility_(2018-10-01)_01.jpg

 

[Steve Shannon]

Ones that require grain bonding or Epoxy assembly, should have 5-7 days for the Cure Process to reach maximum strength.

All Epoxies, and most glues, while "set" in 5, 15, 30 minutes, or 2, 4, 24 hours... take days for the "cure process" to finish.

That’s true for strength characteristics, but I was under the impression that epoxy is used as a combustion inhibitor rather than structural strength.

 

[tsmith1315]

How the heck does that work if you drive a hatchback??

Simple, just think outside the box:

 

[OverTheTop]

How the heck does that work if you drive a hatchback??

Technically on a roofrack or trailer.

They don't drive hatchbacks in Australia.

Yes we do. Shiploads of them.

 

[SolarYellow]

Technically on a roofrack or trailer.


Yes we do. Shiploads of them.

Yeah, of course you do, but I wanted to post a photo of a sweet ute.

 

[afadeev]

I am wondering how far ahead of a scheduled launch is it OK to put your reloads together for your motors?

To answer OP's question - as far ahead as you like to plan for your launches!
Just store the engines in an air-tight packaging to avoid moisture ingress, and transport them to the launch site separated from the ignitor (aka - common sense). Other than that, they will last for weeks, months, years. Same as the pre-assembled DMS (disposable) motors.

I know aerotech recommends not opening the road kit until ready for it, but it is nice to do it ahead of the launch if possible for myself. Is the main thing to keep them dry so they don’t take on moisture before the launch? Such as in a low humidity room?

Yes.
Sometimes I assemble motors in the middle of the winter when I can't go out and launch. Just to scratch the itch.

I put my pre-assembled motors into zip-lock bags. There are various sizes available, including jumbo 18" x 24", if you need those.
If the launch is less than a week away, I may not even bother with a zip lock, if none are readily available.
If it's much longer that that and no zip locks are around, just saran-wrap the motor.

HTH,
a

 

[OzHybrid]

That would definitely affect the ability to ship it via a commercial carrier, but as far as I know the end user can assemble a motor and transport it in a private vehicle. Of course have no igniters in motors; that would just be stupid. For years folks have been assembling large motors before launches and then bringing them to the launch.

People have been doing it for years is not a good defence. There seems to be an unreasonable amount of differing views to suggest it's not legally clear. I'd doubt Tripoli would issue a formal statement saying it is OK. Is Tripoli formally saying it's OK. Carried in the cab or external? Maximum weight? What segregation is required? What if batteries are shipped at the same time?
Vehicle insurance?
Expecting individuals to decide individually what is legal is unlikely to get a unified response on legality or transport methodology. ( Wood lined case external to the cab area????)
Seems that there may be some degree of heads being burried in the sand. I'm sure no-one is transporting a fully assembled motor inside thier vehicle..............however convenient that would be.

 

[techrat]

I'm sure no-one is transporting a fully assembled motor inside thier vehicle

Disposable, single-use motors are fully assembled.
The Estes F15's are fully assembled and technically are HAZMAT.
Are you saying that it's possibly illegal for me to put them in my car and bring them to a launch? How else *am* I supposed to use them?

 

[OzHybrid]

Disposable, single-use motors are fully assembled.
The Estes F15's are fully assembled and technically are HAZMAT.
Are you saying that it's possibly illegal for me to put them in my car and bring them to a launch? How else *am* I supposed to use them?

In this instance, my concern would be more about a fully assembled N being transported multiple times to and from a site that's probably a long way from home, as you'd need a high altitude launch site. However, as you are asking me, that means you don't KNOW, and that's an issue.
Again, this is where the international bodies, Tripoli and NAR could provide guidance based on best practice. If that means we all need to buy roof racks with secure boxes, so be it. Better to all be on the right side of police question time than the wrong side. To have some best practice guidelines from our represantive bodies than to not have it

 

[sharkbait]

People have been doing it for years is not a good defence. There seems to be an unreasonable amount of differing views to suggest it's not legally clear. I'd doubt Tripoli would issue a formal statement saying it is OK. Is Tripoli formally saying it's OK. Carried in the cab or external? Maximum weight? What segregation is required? What if batteries are shipped at the same time?
Vehicle insurance?
Expecting individuals to decide individually what is legal is unlikely to get a unified response on legality or transport methodology. ( Wood lined case external to the cab area????)
Seems that there may be some degree of heads being burried in the sand. I'm sure no-one is transporting a fully assembled motor inside thier vehicle..............however convenient that would be.

Gasoline is a C3 Hazmat flammable liquid, nobody is out busting Harry Homeowner for transporting a 5 gallon can of it around for his lawnmower, however the big rig commercial drivers transporting a 10,000 gallon tanker full of it follow a different set of rules

 

[OverTheTop]

Down here motors technically have to be transported in a wood-lined box, and not in the passenger compartment.

 

[OzHybrid]

Gasoline is a C3 Hazmat flammable liquid, nobody is out busting Harry Homeowner for transporting a 5 gallon can of it around for his lawnmower, however the big rig commercial drivers transporting a 10,000 gallon tanker full of it follow a different set of r

What's your point. There's nothing here I'd take to court.