Ooops, edit.

I think I found the answer as 1965, MRN, Alpha. I know this was on YORF somewhere, if I just kept looking.

So I will make all of my pre-1965 models with slit tube mounts, except the Cobra with fin mount.

Thanks!

Yes. December 1965 MRN (Volume 5 number 3), which had the trip-fold in the Idea Box and also introduced the K-25 Alpha. As far as I know the Alpha represents the first Estes kit that had the tri-fold as the shock cord mounting method from the outset.

It made its way to some of the earlier K-kits in revisions to instructions some time later. For example the Ranger, Skyhook and Big Bertha instructions on JimZ show the tri-fold. The much earlier Big Bertha instructions on YORP show the two-slit method.

And I know I've seen K-20 Mars Snooper instructions somewhere showing the tri-fold, but I don't recall where it was now.

The Alpha also introduced to Estes kits the steel engine hook used simply as a quick-change retainer, even though that hook itself first appeared in the Sprite.

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

Yes, thank you. My confusion (and a lengthy first version of my post/question) actually stemmed from the Ranger and Big Bertha, which I am building in 1963 form. My Astron Ranger plans (the widely available pdf) has the tri-fold, and I only realized recently that these plans must be a revision post-1965, and would not apply to my 1963 project.

Thanks for that bit of trivia, in particular that the engine hook, as we typically know it now, first appeared in the *Sprite*; I did not know that.

I have never had a Sprite kit, but just thought its ‘engine retainer’ was much like the one used in the Estes Scout (round metal rod stock). I had always thought the Alpha was the first use of the ‘flat’ metal engine hook.

Earl

__________________
Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

The Sprite, of course, was made for the Series III engines — the short 18mm ones — so the EH-2 hook worked the same way in it as that long piece of 1/16 music wire did in the Scout. Though in my experience it wasn't quite a good at keeping the motor from being spit out altogether — either on the original kit or the Semroc Retro-Repro which was very faithful.

The Sprite and the Streak were my first two rockets, though I don't recall now in which order. My first Alpha was shortly after that, but I don't know when exactly. My first scratch-build was my fifth. I still have that one. But the Sprite, Streak and Alpha are long gone.

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

I have built 5 or 6 Astron Streaks.
Only recovered one. The first few were on A8-5s and never saw them again.
The last one I painted fluorescent orange and loaded it up with a C6-7 for a fire-and-forget special.
Launched in zero wind at ground level.
It must have got all of 2000'.
Landed 25' from launch pad.
It was immediately retired upon recovery.
That was in the summer of 1988 right after HS graduation.
I have the same luck with Mosquitoes.
Only recovered one of 5 or 6 and that one was on an A3-6T with fluorescent yellow/black finish.
1/4A and 1/2A flights all losses.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

Yep…and it was that similarity of function that had made me incorrectly assume that they both used the same kind of wire retainer, though the Sprite’s — in my mind, I thought — was just shorter to accommodate the shorter Series III engines.

Just another case of ‘quick-glance assuming’ not being true to reality.

Earl

__________________
Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

OK, I did finally locate a set of Astron Ranger K-6 instructions that are early enough to call for the slit tube shock cord mount (way down near the fins/motor mountl). It's the top set, 4 pages.

Astron Ranger K-6 Type I

The two-slit method prior to the tri-fold attachment of shock cords was MAJOR LEAGUE FUGLY.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

This is another case where we agree. The two-slit method is ugly. Neither it nor the tri-fold is so great in small tubes (BT-5, BT-20) for pretty much the same reason....getting in the way of getting the recovery system out.

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE