The Understated Estes Alpha.

[mh9162013]

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.

View attachment 536611

You ever try launching an Alpha or Alpha III with a D composite 18mm engine?

 

[Scott_650]

A seven year old thread that’s been revived multiple times with over 7 pages of posts - I’d say the Alpha is a very significant design!

 

[Hobie1dog]

I wonder how many alpha rockets that Estes has sold?

 

[GlenP]

A seven year old thread that’s been revived multiple times with over 7 pages of posts - I’d say the Alpha is a very significant design!

Yes, I think this rocket has been Stated.

 

[BEC]

You ever try launching an Alpha or Alpha III with a D composite 18mm engine?

I have not (yet). Perhaps that's something to try on our next visit to TCR's sod farm flying site. The Q-Jet Ds both are low Ds at less than 14 N-s, and since both are pretty high thrust a bunch of that extra performance gets soaked up in higher drag. In flying a larger BT-50-based model quite a bit, including on the Ds, the resulting altitude is not really proportional to the added impulse.

I once sent a BMS School Rocket up on an Aerotech D10. As I recall the altimeter aboard (which was much heavier than today's devices) reported something like 1700 feet. It was sheer luck that I got that one back.

 

[gldknght]

Hey, besides my two Alphas (one 33 years old, one 3 years old), I have an Alpha III, and a question. Will the fin can hold paint? I really dislike the stock colors.

It sure will. I just re-finished my Alpha III a couple months ago. And painted the fins and nose cone on my Maxi Alpha blue so it would look a little different from everyone else's:

 

[gldknght]

Oh, and my scratch built Alpha Max. It's first flight was on a parachute that was a little too small. Broken fin was repaired but not repainted:

 

[SolarYellow]

I'm planning to do a couple of Alpha downscale builds, and need nose cones.

Can anyone point me at a BT-5 and a BT-20 nose cone that are proper downscales of the current or vintage Alpha nose cones? It's kind of fiddly to sort through all the drawings at BMS and erockets, just wondering if someone knows for sure, "This one and this one."

 

[bcook7135]

I used an original Alpha in high school to run experiments for the Science Fair. I was fortunate to be awarded 3rd place in the Georgia State Science Fair in 1978-79. It is a great rocket.

 

[BEC]

I'm planning to do a couple of Alpha downscale builds, and need nose cones.

Can anyone point me at a BT-5 and a BT-20 nose cone that are proper downscales of the current or vintage Alpha nose cones? It's kind of fiddly to sort through all the drawings at BMS and erockets, just wondering if someone knows for sure, "This one and this one."

It depends on how fussy you want to get, and which shape you want to reproduce as to what constitutes a "proper downscale". There are two main Alpha nose cone shapes. The first is the original balsa BNC-50K, which was used from the Alpha's debut in late 1965 through about 1982. That shape which was reproduced pretty faithfully in the first blow-molded nose cone used in Alpha kits (and other Estes kits) circa 1982-1989.

The other shape is the noticeably "pointier" blow molded nose cone that was in Alpha kits starting ~1992 and which continues to the present time.

In between (circa 1989-1992) you could get either shape in blow-molded plastic OR get the injection molded nose cone from Alpha III in an Alpha kit. And thereby hangs a tale that I'd love to know, though I have some speculations.

Anyway, for BT-20, the BC-719 Semroc nose cone at eRockets.biz would be pretty close to the earlier (1965-1989) shape though it's a little too pointy and being for ST-7 tubing would have a shoulder that's a bit proud when used on BT-20 tubing. Another option would be BNC20G3, but that's a touch too long. For BT-5, either the BNC-5E or the BC-512 would be fairly close.

I don't know of any plastic substitutes — there's nothing in the currently-available Estes nose cone assortments that are even close. I don't have the inclination at the moment to look at other vendors for plastic options right at the moment. I also haven't looked at BMS's listings. His "BNC-50K" is really much closer to the shape of the PNC-50K (the Alpha III nose cone), but I don't know about smaller tangent ogives he carries.

Happy hunting.

 

[Rocketteer]

I'm planning to do a couple of Alpha downscale builds, and need nose cones.

Can anyone point me at a BT-5 and a BT-20 nose cone that are proper downscales of the current or vintage Alpha nose cones? It's kind of fiddly to sort through all the drawings at BMS and erockets, just wondering if someone knows for sure, "This one and this one."

You can also check ASP Rocketry

 

[JRL303]

You ever try launching an Alpha or Alpha III with a D composite 18mm engine?

Indeed! Aerotech D13-7W. Fantastic stuff.

 

[Hobie1dog]

I have an old Alpha Max (big one) that needs repainted. Likely won't find the original decals so might custom paint it.

 

[rharshberger]

It depends on how fussy you want to get, and which shape you want to reproduce as to what constitutes a "proper downscale". There are two main Alpha nose cone shapes. The first is the original balsa BNC-50K, which was used from the Alpha's debut in late 1965 through about 1982. That shape which was reproduced pretty faithfully in the first blow-molded nose cone used in Alpha kits (and other Estes kits) circa 1982-1989.

The other shape is the noticeably "pointier" blow molded nose cone that was in Alpha kits starting ~1992 and which continues to the present time.

In between (circa 1989-1992) you could get either shape in blow-molded plastic OR get the injection molded nose cone from Alpha III in an Alpha kit. And thereby hangs a tale that I'd love to know, though I have some speculations.

Anyway, for BT-20, the BC-719 Semroc nose cone at eRockets.biz would be pretty close to the earlier (1965-1989) shape though it's a little too pointy and being for ST-7 tubing would have a shoulder that's a bit proud when used on BT-20 tubing. Another option would be BNC20G3, but that's a touch too long. For BT-5, either the BNC-5E or the BC-512 would be fairly close.

I don't know of any plastic substitutes — there's nothing in the currently-available Estes nose cone assortments that are even close. I don't have the inclination at the moment to look at other vendors for plastic options right at the moment. I also haven't looked at BMS's listings. His "BNC-50K" is really much closer to the shape of the PNC-50K (the Alpha III nose cone), but I don't know about smaller tangent ogives he carries.

Happy hunting.

Didn't Jack Hydrazine to a .stl for 3d Printing the PNC-50K?

 

[BEC]

Didn't Jack Hydrazine to a .stl for 3d Printing the PNC-50K?

Now that you mention it, I think he did. But I can't find his note about it. He generally posted on YORF at the same time he did on the RocketsNW mailing list when he released a new 3D printer file, and I've found lots of other nose ones for BT-50, but not anything "50K".

I also don't recall if it was PNC-50K (the Alpha III nose cone), PNC-50KA (which has been used for both the first and then the later blow-molded Alpha nose cones)....

 

[rharshberger]

Now that you mention it, I think he did. But I can't find his note about it. He generally posted on YORF at the same time he did on the RocketsNW mailing list when he released a new 3D printer file, and I've found lots of other nose ones for BT-50, but not anything "50K".

I also don't recall if it was PNC-50K (the Alpha III nose cone), PNC-50KA (which has been used for both the first and then the later blow-molded Alpha nose cones)....

Just checked his Thingiverse...nothing for the PNC-50K or KA.

 

[SolarYellow]

Well, I got home and did this tonight. Measured a current Alpha kit nose cone, then scaled based on BT ODs. Nothing at erockets quite matches, but I could probably live with the BC-514 and BNC-20G3. They're probably close enough that playing with the BT length a little to get the LOA closer (but not necessarily exact) would maybe be worthwhile.

 

[BEC]

BNC-20B is an elliptical nose cone....originally used on the Apogee II, Gyroc, the glider on the Orbital Transport and others. It would be kinda close if you were going for an Alpha III sort of look instead. The Alpha III's nose cone is much more elliptical than ogive/tangent ogive.

As an aside, the new Super Orbital Transport has a lovely blow-molded BT-50 nose cone that's a faithful upscale of the BNC-20B, but that's going the other way.....

 

[SolarYellow]

Probably more efficient at 24mm BP speeds in any case.

ETA:
I found the 072610 nose cone. It's colored yellow. Appears to be part of the 001497 "Customizer Mini" kit, as well as the 3031 Star Trooper. A little bit shorter fineness ratio, perhaps, but not too far off if I prefer PNC to BNC.

 

[Hobie1dog]

my gifted Maxi Alpha, circa 1980 I doubt that there are any decal sets available.

 

[SolarYellow]

Love those '70s graphics. You should take good pictures and measurements and post them.

 

[Hobie1dog]

Love those '70s graphics. You should take good pictures and measurements and post them.

I found the original plans online:
https://plans.rocketshoppe.com/estes/est1291/est1291.pdf

 

[DigBaddy]

my gifted Maxi Alpha, circa 1980 I doubt that there are any decal sets available.

This looks like it https://stickershock23.com/product/estes-maxi-alpha-3-2/

 

[Hobie1dog]

This looks like it https://stickershock23.com/product/estes-maxi-alpha-3-2/

thanks for the link, awesome. now that I know they're available, I can plan on restoring it.

 

[rharshberger]

my gifted Maxi Alpha, circa 1980 I doubt that there are any decal sets available.

Easy to make with a Inkjet and or Laserjet printer if you have some decal paper, or someone is willing to make you some. The image files are probably available from JimZ's website.

 

[SolarYellow]

For a restoration, I would try DIY waterslide before buying vinyl. But test, test, test and repeat some more before doing it on the actual rocket.

 

[Hobie1dog]

I will struggle with changing the colors after seeing the silver body instead of the white original colors. I just like to have something unique instead of having the same exact rocket 500 other people have.

 

[SolarYellow]

For the restoration, I would focus on mechanical soundness and originality. Touch up dings, dents and scratches and make sure it has integrity in the recovery system and overall mechanical strength.

Then just buy some parts (PNC-80K is available from edu.estesrockets) and build a new one with all new parts.

Even before you posted this, my build list has had a BT-80 Alpha with birch ply TTW fins and a 29mm MMT. Would be fun to send it with a G76.

 

[Hobie1dog]

For the restoration, I would focus on mechanical soundness and originality. Touch up dings, dents and scratches and make sure it has integrity in the recovery system and overall mechanical strength.

Exactly what I want to do with it. I may take it to the next launch and just put a new chute in it to see how it does with the recommended D12-5

 

[Ez2cDave]

We have been remiss . . . There has been no mention of the "Uprated Alpha" by Dr. Gerald Gregorek.

This, also, "opens the door" for an "Uprated MAXI-APLHA" !