The Understated Estes Alpha.

5x7 said:

I looked at the built rocket and the instructions and it's the motormount version with the single fat cylinder cr (ick). In the picture below it is the middle facecard. The facecard on the left of the middle appears to be the version with black decals but I can't recall them being black (long story for that one) they both have identical instructions. I added an Alpha 3 and 4 for completeness. The funny thing about the instructions for the kits with the huge alpha decals is they have the nosecone part listed as either the PNC50ka blow molded or the pnc50k injection molded alpha 3 version with the screw eye.

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I happen to have a built model with the black stripe on the fin from circa 1986-ish.

I started converting a Halloween Alpha to match my original, circa 1980-81. This is the second rattle can of Testor's Dark Red that has sprayed in large splotches instead of the fine mist as it should. In order to get it to cover completely and then self-level, I had to spray it kind of heavy, which caused runs to the fin tips. I'll try to mask and spray the decal pattern with black, using the Halloween decals as a guide.

TangoJuliet said:

This is the second rattle can of Testor's Dark Red that has sprayed in large splotches instead of the fine mist as it should.

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I started storing my spray bombs upside down about a year ago.
Since (primer only until warmer weather) then the spitting chunks and clogged feeder tubes have been non-existent for me. Might be worth a try.

The Alpha III was my first rocket. It flew well and I don't recall any problems packing the parachute.

Anybody got a scan of the Red and Black Alpha decals they would like to share?

I have a set of those decals.....let me see if I can get 'em scanned for you tomorrow (well, later today), Rich.

For a rocket with lots of space, I love the Estes Patriot scale model... Easy to build, big fat BT-60 with a 12" chute, and doesn't take much space to launch at only 500'. Not to mention the fact that it's a scale model. The only issue I've had is that the MMT is a bit flimsy - it's fine with standard motors, but I wouldn't trust it with an AT D21...

BEC said:

I have a set of those decals.....let me see if I can get 'em scanned for you tomorrow (well, later today), Rich.

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Thanks Bernard.

Here you go. Hopefully this will not be too big to upload.....

Should have named the file "B&R...." not "B&W..."

View attachment B&W Alpha decal.pdf

Thanks Bernard

Gary Byrum said:

I now have a BT 101 upscale......

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Hey Gary, old thread and post, but might you still have these scaled fin drawings someplace?

Jon

JonathanOtt said:

Hey Gary, old thread and post, but might you still have these scaled fin drawings someplace?

Jon

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I do. Let me know which scale you need. And what type of file do you need. I draw in Autocad and can print a scale PDF. Maybe we should take this to messenger?

Gary Byrum said:

I do. Let me know which scale you need. And what type of file do you need. I draw in Autocad and can print a scale PDF. Maybe we should take this to messenger?

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Going to messenger...or "Conversations" here on TRF.

JonathanOtt said:

Going to messenger...or "Conversations" here on TRF.

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I'm pretty sure we're talking about the same thing. That conversation side chat thingy?

Gary Byrum said:

I'm pretty sure we're talking about the same thing. That conversation side chat thingy?

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Yep. Just posted.

I love the alpha and all its variants. I just happen to have a BT60 tube that's the right length for a Super Alpha repro / scratch build

BEC said:

I would love to get my hands on an original SP-25. I have the instructions from my original Alpha build in the late 1960s but of course used the SP-25 in that build.

For your cringe-worthy amusement, here's the fin shape thread. https://www.rocketryforum.com/showthread.php?15600-vintage-astron-alpha-fin-pattern

Which leads to - do you have a scanner? Could you actually scan that pattern and the ruler and post the file? I'm curious if there is any difference between the post-Damon SP-25 you have with the earlier one that Rex posted in that other thread. I sincerely hope that the only difference is the logo information.....

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I know this post is several years old but did you ever find and sp25? I have a new sealed one

Rocketteer said:

I know this post is several years old but did you ever find and sp25? I have a new sealed one

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I've acquired several Damon-era kits with SP-25 in it, either separately or on the back of a kit face card. But I would still love to get my hands on an earlier, pre-Damon example, even though I expect the fin shape to be unchanged.

...and related to the general tone of this thread....I am in the throes of creating a "50th Anniversary Alpha III" since this year is its 50th of continuous availability. It will fly at NSL.

BEC said:

I've acquired several Damon-era kits with SP-25 in it, either separately or on the back of a kit face card. But I would still love to get my hands on an earlier, pre-Damon example, even though I expect the fin shape to be unchanged.

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I'll let you know if I come across one.

I have a question for all you Alpha experts.

Is the Alpha one of those rockets that does not really need 1 caliber of stability to fly well?
I'm guessing no because it's kind of short and the motor is recessed way up into the fins?
This is for a 3" upscale with a 54mmt. Even with electronics in the nose cone..it's hard to stay sim motors staying above one caliber..(I already have some nose weight in it)

Asking for a friend!

Tony

No connection to seller, I found this old kit on fleabay:

https://www.ebay.com/itm/125115167690
Photos might be worth archiving for an Alpha nerd.

@SolarYellow Wow, that guy is still trying to sell that partial build for a bunch of money. That’s been up there for months off and on. That’s the original style motor mount assembly, if anyone cares.

@tfish : this is a late answer, but….the current kits have the motor mount moved aft 3/8ths of an inch and have a heavier mount assembly than the original (see post just above) or the two-AR2050-ring style mount and they are still quite stable even on the heaviest motor that will fit (Estes C6-7) so I would think if your upscale had the nozzle-end of the motor was projecting aft no more than 3/4 of an inch — which would be 3x the original dimension — it should be OK. At least that’s how it seems to this guy whose largest flown composite motor case is a 4-grain CTI 29mm, and who has never built a composite or fiberglass rocket.

tfish said:

I have a question for all you Alpha experts.

Is the Alpha one of those rockets that does not really need 1 caliber of stability to fly well?
I'm guessing no because it's kind of short and the motor is recessed way up into the fins?
This is for a 3" upscale with a 54mmt. Even with electronics in the nose cone..it's hard to stay sim motors staying above one caliber..(I already have some nose weight in it)

Asking for a friend!

Tony

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The Estes Alpha (671-K-25) (circa 1967) had a stability caliber of about 1.17.

tfish said:

I have a question for all you Alpha experts.

Is the Alpha one of those rockets that does not really need 1 caliber of stability to fly well?
I'm guessing no because it's kind of short and the motor is recessed way up into the fins?
This is for a 3" upscale with a 54mmt. Even with electronics in the nose cone..it's hard to stay sim motors staying above one caliber..(I already have some nose weight in it)

Asking for a friend!

Tony

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The Alpha has crazy oversized fins and stability is not much of a concern with upscales and downscales. I am speaking from firsthand experience.

The sim numbers notwithstanding, I think the Alpha is short. Estes has done stretched Alphas (Hi Jinks, Athena, et al.) that look better IMO. The swept back fins moving the CP aft make the Alpha work. Swept back fins was a signature of Estes designs in the 1960's. Probably looked more "rockety" but it did allow stable flight with shorter airframes as well.

Thanks for the info.
I have about 20 flights on it now. I was worried mostly about the one grain 54mm motors. I've flown about 8 of those now..without any issues.

Tony

samb said:

The sim numbers notwithstanding, I think the Alpha is short. Estes has done stretched Alphas (Hi Jinks, Athena, et al.) that look better IMO. The swept back fins moving the CP aft make the Alpha work. Swept back fins was a signature of Estes designs in the 1960's. Probably looked more "rockety" but it did allow stable flight with shorter airframes as well.

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One of the easiest ways to bump apogee in OpenRocket is to shorten the BT - if the fins support it with good stability.

samb said:

The sim numbers notwithstanding, I think the Alpha is short. Estes has done stretched Alphas (Hi Jinks, Athena, et al.) that look better IMO. The swept back fins moving the CP aft make the Alpha work. Swept back fins was a signature of Estes designs in the 1960's. Probably looked more "rockety" but it did allow stable flight with shorter airframes as well.

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So true. On my backwards fin Alpha the stability tanked, and I had to compensate with a lot of nose weight to make it stable again.

lakeroadster said:

The Estes Alpha (671-K-25) (circa 1967) had a stability caliber of about 1.17.

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I have to smile at that altitude calculation. Estes packaging has claimed anywhere from 1000 to 1500 feet for the Alpha over the years....and I think they are currently at 1000 feet. I have data to show that a C6-5/7 will take an Alpha (with rounded edge fins, not square ones) to 1000 feet or a little more. To get to 1300 requires a Q-Jet C. My wife put hers (which is built pretty much to the K-25 version simulated here from mostly Semroc parts) to 1309 feet (and roughly Mach 0.5) on a C18-6W at Sod Blaster IV. Based on that, a C12, which wastes less energy in drag, would likely take the same model to 1400-1450 feet I would guess. Here is a frame capture from a slow motion iPhone video of the boost on that flight.