AeroTech Challenges CTI 10-Second Assembly Claim

[Bazookadale]

I know how to resolve this!

https://www.youtube.com/watch?v=XyhhFzE5O5U

I've never understood why she stopped that - it was supposed to be a fight to the death!

 

[Adrian A]

I've never understood why she stopped that - it was supposed to be a fight to the death!

And how did Kirk's shirt suddenly heal itself halfway through the fight?

 

[cjl]

I honestly don't care how long motors take to assemble. I buy a motor because I like its performance/visual characteristics and it fits the rocket that I want to fly.

 

[Jeroen_at_CTI]

I honestly don't care how long motors take to assemble. I buy a motor because I like its performance/visual characteristics and it fits the rocket that I want to fly.

For visual effects nothing beats ZnS (micrograin). The problem is: typically the rocket and the flame are gone before you got to see it. Ohhh, these good old days:

There is a 30 ft tower somewhere underneath there.

 

[DAllen]

Joe, this is all in the spirit of "good, clean competition"...sometimes I think those days are long gone...the days when Vern Estes and Lee Piester exchanged catalogs and "crying towels".

I sincerely hope this thread doesn't degrade into personal attacks...

Glad to hear that.

I've already been called an a**hole by Jeroen's boss as a result of this discussion.

Uhh...If this is all in good fun then why bring THAT up? Be the bigger man. Ignore the name calling and don't bring it up in an internet forum even if he does. Nothing fuels drama better than the addition of more drama.

-Dave

 

[nh4clo4]

For visual effects nothing beats ZnS (micrograin). The problem is: typically the rocket and the flame are gone before you got to see it. Ohhh, these good old days:

There is a 30 ft tower somewhere underneath there.

:eyepop:

That is simply amazing! So... when will we see some CTI micrograin reloads ?

 

[als57]

It takes even less time when you forget the casing.

-- Roger

I've seen the results of that.:y:

Not pretty!

Al

 

[patelldp]

Let's just say that this crap makes me very happy I own Loki hardware.

 

[Garoq]

Uhh...If this is all in good fun then why bring THAT up? Be the bigger man. Ignore the name calling and don't bring it up in an internet forum even if he does. Nothing fuels drama better than the addition of more drama.

-Dave

You're probably right, I removed that statement.

 

[JoeG]

Well I agree with you. The point of the challenges is not to show that AeroTech motors assemble as fast as CTI, we all know that's not the case, just that there's not that great of a difference. I personally don't think it matters much that a motor takes 30 seconds or three minutes to assemble. Do people buy kits based on whether one takes 5 or 10 minutes longer to build than another? Others may disagree.

Someone once said "the journey is more important than the destination", or something like that?

Well said young grasshopper.

 

[ben_ullman]

Let's just say that this crap makes me very happy I own Loki hardware.

Heres vote 2 for snap rings

Ben

 

[MarkII]

"People, I just want to say, you know, can we all get along? Can we get along?..." - Rodney King, 5/1/92

Rivalry is OK, whether it is friendly or not. Just as long as it is focused on the products, and not on the people.

OK, so which one of you is a Mac, and which one is a P.C.? :confused2:

MarkII

 

[MaxQ]

Let's just say that this crap makes me very happy I own Loki hardware.

I have Loki hardware, ....and Cessaroni (purchased after the great Aerotech factory fire and subsequent motor famine of long ago).

And I still use Aerotech, and love them.

Variety is the spice of life.

 

[blackjack2564]

Someone once said "the journey is more important than the destination", or something like that?

" A world class traveler understands........... "

" The Art of travel is enjoying the Journey to the Destination"

CJ

 

[RocketMonkey]

Well I agree with you. The point of the challenges is not to show that AeroTech motors assemble as fast as CTI, we all know that's not the case, just that there's not that great of a difference. I personally don't think it matters much that a motor takes 30 seconds or three minutes to assemble. Do people buy kits based on whether one takes 5 or 10 minutes longer to build than another? Others may disagree.

Someone once said "the journey is more important than the destination", or something like that?

Where we fly here in San Diego, we often are held hostage by the wind so having a motor that can be built in 3 minutes without worring about which o-ring goes where and did I remember to put on the ejection charge or having to get out your greese, or peel a liner to get it to fit is a plus when your trying to get in a launch durring a short lul in the wind, that being said I also fly AT stuff and like tem too, varity is the spice of life and all.

 

[cjl]

For visual effects nothing beats ZnS (micrograin). The problem is: typically the rocket and the flame are gone before you got to see it. Ohhh, these good old days:

There is a 30 ft tower somewhere underneath there.

:y: :eyepop: :jaw:

When does that come to Pro38 hardware then?

 

[Graham Orr]

threads are generally a better engineering practice.

the snap ring groove (even with same wall thickness) has a stress concentration factor of 1.5 or so.

CTI, what radius is used on your groove? in materials science, the radius will determine the fatigue characteristics of the joint.

also, i'm assuming 6061T6 alum on both cases? type 2 anodized?

 

[terryg]

For visual effects nothing beats ZnS (micrograin). The problem is: typically the rocket and the flame are gone before you got to see it. Ohhh, these good old days:

There is a 30 ft tower somewhere underneath there.

Whoa .... :jaw:

You can not post a picture like that and walk away ....
More information please for those of us who missed the good old days! Are there any videos?

 

[DAllen]

OK, so which one of you is a Mac, and which one is a P.C.? :confused2:

Neither CTI or AT is nowhere near unreliable enough to be called a PC. Let's face it...Since rocket science is involved neither is cool enough to be called a Mac.

lol

:roll:

-Dave

 

[sylvie369]

Someone once said "the journey is more important than the destination", or something like that?

Maybe more importantly, no-one ever said "I like my hobby activities to take 10 seconds or less".



I really like having motors available from more than one manufacturer.

 

[Jeroen_at_CTI]

You can not post a picture like that and walk away ....
More information please for those of us who missed the good old days! Are there any videos?

See 'Pictures from the past (1) and (2)' here: https://home.planet.nl/~koste129/galleries.htm
I think the largest motor ever tested had around 400 lbs of propellant. Required a crane to be put in place. There was a lot of ZnS flown in the 70's-90's by Belgium/Danish and European Amateurs. I think it was also quite popular in the West of the US at the same time.

Just a note: do _NOT_ try this at home. It is extremely dangerous to mix and load and I have heard about way too many accidents. Certified composite reload kits are much safer.

Jeroen

 

[stickershock23]

I shouldn't get into this but...

You build your own rockets. when are you going to start building your own motors?

of course Variety is always nice. I've flown them all, and can honestly say I don't have any complaints.

 

[Garoq]

See 'Pictures from the past (1) and (2)' here: https://home.planet.nl/~koste129/galleries.htm
I think the largest motor ever tested had around 400 lbs of propellant. Required a crane to be put in place. There was a lot of ZnS flown in the 70's-90's by Belgium/Danish and European Amateurs. I think it was also quite popular in the West of the US at the same time.

Just a note: do _NOT_ try this at home. It is extremely dangerous to mix and load and I have heard about way too many accidents. Certified composite reload kits are much safer.

Jeroen

ZnS motors are very cool. I had the opportunity to witness a number of flights at the MTA in California in the early '70s.

 

[shreadvector]

ZnS motors are very cool. I had the opportunity to witness a number of flights at the MTA in California in the early '70s.

You saw some at Smoke Creek in the early 1980's as well.

 

[Garoq]

You saw some at Smoke Creek in the early 1980's as well.

Also the RRI KClO4 + asphalt HVAR rockets.

 

[tquigg]

Every manufacturer's products have issues from time to time...if you browse the forums you will see that they are certainly not limited to AeroTech. I apologize for any problems you have had with ours.

That said, we strive to make the best motors out there and to keep improving, and there are thousands of customers that are quite happy with AeroTech products.

I would be a much "happier" customer if you could come up with a better, more accuarte method/system/tool to dial back your delays, other than a 3/16 drill bit with a piece of tape and "eyeballing" the delay. Not very accurate, as has been mentioned in this thread. The less chance for operator error, the better. IMHO, CTI has Aerotech beat hands down in the delay department with the CTI delay tool. Any chance of producing something like this for Aerotech Gary?

 

[shreadvector]

I would be a much "happier" customer if you could come up with a better, more accuarte method/system/tool to dial back your delays, other than a 3/16 drill bit with a piece of tape and "eyeballing" the delay. Not very accurate, as has been mentioned in this thread. The less chance for operator error, the better. IMHO, CTI has Aerotech beat hands down in the delay department with the CTI delay tool. Any chance of producing something like this for Aerotech Gary?

I use the drill collar exactly as pictured and described in the Aerotech instructions. Very accurate.

https://www.aerotech-rocketry.com/c...tions/RDK_Instructions/rms_delay_mod_inst.pdf

 

[tquigg]

I use the tape method, also described in the Aerotech instructions. Have yet to hit the desired delay "dead on". Always either a couple of seconds too early or a couple of seconds too late, no matter how much I measure the bit before drilling.

I'm not alone. Several other club members experience the exact same problems I do. :confused2:

 

[DaveHein]

AeroTech/RCS will give a $500 AeroTech gift certificate to the first private individual who produces a video proving CTI's claim that a CTI 29 or 38mm motor can be assembled in 10 seconds or less.

https://www.rocketryplanet.com/forums/showpost.php?p=126719&postcount=1

Video must show assembly from start to finish in real time including unpackaging the load, setting the reload's time delay to 10 seconds with the ProDat delay adjustment tool, installing the completed load in the casing and inserting and securing the igniter to the motor.

CTI owners, employees and dealers are not eligible.

It seems like it's possible. I think the following tasks could be completed in the time given:

Open package - 1 second
Drill delay - 3 seconds
Screw motor into the casing - 3 seconds
Insert igniter - 3 seconds

If I had a CTI motor handy I'd give it a try. Hmm, this may cause a run on purchasing CTI motors just to win the $500.

Dave

 

[Adrian A]

It seems like it's possible. I think the following tasks could be completed in the time given:

Open package - 1 second
Drill delay - 3 seconds
Screw motor into the casing - 3 seconds
Insert igniter - 3 seconds

If I had a CTI motor handy I'd give it a try. Hmm, this may cause a run on purchasing CTI motors just to win the $500.

Dave

Opening the package in 1 second would probably require having a nearby table saw spun up before the clock starts. :roll:

I'd say plan to fly it in a minimum diameter rocket, and then adjusting the delay only takes as long as glancing at your rocksim output sheet.

And why is inserting the ignitor before you get to the pad considered part of the SOP? I'd say tape the ignitor to the side of your rocket for the trip to the LCO table.

Then 10 seconds should be quite do-able.