"Electronic Forward Closure"

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McKailas Dad

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Ok, so I'm still an 18mm LPR guy :eek:, but I'm looking into getting a Aerotech 24/40. I see they have the 'EFC-1' for 29, 38 and 54mm, do you think they may offer one in a 24mm size? I see all the posts on 'drilling the delay', and all the problems associated with that, and it just seems kinda sketchy to me? Is the EFC-1 the answer to all the delay issues?

Thanks,
 
To the best of my knowledge, there aren't any issues with 24mm RMS delays; just buy the reloads that have the delays that you need. The EFC would dwarf the 24mm RMS motor anyway. It is basically a timer (a real nice one, though), but it is priced comparable to an altimeter. Unlike an alt., though, it doesn't require its own bay; the bay and charge holder are built in, as is the igniter, a glow plug. Still, for a 24mm motor, it would be a solution in search of a problem, and it's bigger than the motor itself! (It measures 4.82" long by 1.125" in diameter.) Adapting it down to a 24mm motor would be an interesting bit of engineering.
 
No, They do not.
I have the system & they do have a 29mm x 40-120 forward closure for it, but that's it. The casing on the EFC-1 is actually a 29mm & would not fit into a 24mm or smaller rocket. The timer itself barely fits in there....



JD
 
MarkII said:
(It measures 4.82" long by 1.125" in diameter.)
Wow, I didn't realize it was that hefty. Don't quote me on this, yet, but I'm guessing as small as electronics are getting nowadays, it may not be too far behind?
I saw an 'Altimeter One' in person the other day....tiny!

Thanks for info, (cowering back to the LPR forum)
 
The electronics can be tiny, but it still requires a well for the charge, something to set the charge off, and a battery to power the charge-setting-off stuff. That's what makes things bigger. :)
 
Ditto what MarkII said about the delays. With 24mm RMS reloads, you choose the motors with the delays you want, just like single use motors. As far as I know, you don't have to start drilling delays until you get into 29mm, 38mm, and bigger high power reloads. The 29mm low and mid power reloads I've seen (up to G) also come in various delay lengths.

The best prices I've seen on the 24/40 hardware and reloads is at Hobbylinc:

https://www.hobbylinc.com/htm/aro/aro91241.htm

I bought one this year and some E18-7W reloads (the W stands for White Lightning propellant). Loading the motors was a little daunting at first, but they come with pretty good instructions. Just read the instructions over several times before you load your first motor. There are a couple of different thickness o-rings and other parts that have to be in the right places. But my first reload launch was successful, although I probably could have used a reload with a 4 second delay. FYI, the pink powder the LCO mentioned over the PA system is actually orange chalkline chalk.

https://www.youtube.com/watch?v=ldMk8CJlNBI
 
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For the most part, you can always find a delay available for the 24 & 29mm motors that will work. I've only drilled one delay and that belonged to someone else. Check the Aerotech site, they have the list of delay elements for each motor and a cross reference list of what motors use each delay element. You can buy extra elements and select the one you need for the correct delay in your motor.

My advice would be to buy two or more 24/40 cases right away. They are great and with more cases, you can fly more between having to stop and clean cases. You also can't beat the price at $5.58 per motor for F24W at Hobbylinc.com. That's almost less then what the price of Estes D12 motors are at the LHS.
 
Yes, Hobbylinc definatly seems the most popular choice for RMS supplies. Having had over 200 (18mm) launches in 7 months, is leading me to believe 2 things; #1, I'm addicted to rockets, #2, RMS seems the next logical step.

I've been trying to do my homework, before I just jump into it though. It seems alot of you guys build rockets with 29mm mounts, and use something like the 'MMA-1'. (Isn't that just a cardboard tube?) to run 24mm.

I'm pretty sure a 24/40 setup would be quite sufficient for me. While the field I launch in now is quite large, I've almost lost a few 'C' launches. I've probably witnessed at least a dozen mid and high power rockets launched at Bong, to never be seen again. I don't mind losing a $15-20 Estes, but losing a $80-100 (plus RMS) Wildman would, for lack of a better word, suck. :hot:

Still researching...advise appreciated!
 
I haven't heard of an EFC before, and am a bit curious, is there a well whenyou can put the Ejection charge in, or do you have to buy the ejection canisters individually?
SD
 
...I've been trying to do my homework, before I just jump into it though. It seems alot of you guys build rockets with 29mm mounts, and use something like the 'MMA-1'. (Isn't that just a cardboard tube?) to run 24mm.

I'm pretty sure a 24/40 setup would be quite sufficient for me. While the field I launch in now is quite large, I've almost lost a few 'C' launches. I've probably witnessed at least a dozen mid and high power rockets launched at Bong, to never be seen again. I don't mind losing a $15-20 Estes, but losing a $80-100 (plus RMS) Wildman would, for lack of a better word, suck. :hot:

Still researching...advise appreciated!
The 24/40 is a great way to get into AP, and learn how to build motors. It used to be by far the cheapest way to fly full E motors, but the E15 3packs at valuerockets are almost as cheap now. I still prefer RMS, I've seen way too many SU motors CATO. The E18 and F24 are my favorite loads. The F24/F39 reloads are almost as powerful as the 29mm Econojets, and 1/3 the price. I wouldn't bother with the D9/D15 loads (I have a couple D15 loads left, you can have them if you want), I've found I'd just rather use a D12 BP. The Rouse-Tech case generally costs quite a bit less than the AT case, and is identical.

It really depends what you want to fly with them - most Estes 24mm rockets will fly really, really high on an E18 - so you'll want a large field. I often use my 24/40 in AT kits when I fly at our club's smaller field. Bong is suitable to fly some larger estes kits on an E or F. The Estes Big Daddy is a good inexpensive kit to fly on smaller fields with E reloads without going out-a-sight.
 
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