Estes Optima Repair/ Shadow Build/ Optima Clone

What can I say, I've got a thing for BT-80.

I picked up all my old rockets that had been sitting around 10 years, and had a few in progress. My father also gave me his Optima, which is in need of repair.

The Shadow had cracked a couple fins, but was otherwise just unpainted. I glued up the fins, and wood filled them up. Sanded down and the first coat of primer is now drying. When I built her, I had added a nylon chute, and it has a MMT mounted cord. Would have liked a baffle in the exhaust tube, but I don't think I'll try to add one. Possibly a nomex blanket, these things use too much wadding.



The Optima was my father's only personal rocket, and saw quite a bit of flying. The fins have come off or cracked a few times on landing, and are currently loose. The paint was never quite thick enough, and it's thinned out in places. The vinyl decals have come loose and bubbled. And the recovery system is in shambles.

I don't know if I want to just get her flyable again, or do a full or partial restoration. Since a full restore would basically involve building an entire new rocket, I'm leaning toward flyable or partial. I have new metal flake vinyl, but it's not a perfect match. I may just replace the fins' decals and save the one on the BT, along with the waterslide. That would let me sand, fill and repair the fins. Then a quick coat of white and it should be decent.

No matter what I do, the recovery system needs to be entirely replaced. I've already cut out the 6" rubber band that was left, and sliced off the chute lines. Since it'll only ever see D12's inside, I plan to put a big ole 28" nylon on it. Not sure on the shock cord material yet. Elastic would probably do just fine. Whatever it is, it'll be mounted to a plywood centering ring I'm gonna stuff down as far as I can get it.




The third bit of this post, I had attempted to build a 72" BT-80 rocket. It was never launched as I never felt quite comfortable with it. So, I Basically decided to slice it in two, making one a phoenix style rocket, and the other is becoming an Optima project. Splitting out the exhaust tube from the bottom section was a bit of a pain, but now taken care of. I need to find a fin template, and remove the old fins. Also I can't seem to find a matching nosecone, but I'm sure a quick search will turn up some options. I've got a few colors of metal flake vinyl, a color shift is probably in order for this one. Then most likely a stickershock Optima logo.

I know better. :hot::y:

Oh well. more sanding in my future.

Was your Optima primed? :duck:

Sorry, I couldn't resist.

I like the looks of the Optima. I never got to see them when they were in production, though.

MarkII said:

Was your Optima primed? :duck:

Sorry, I couldn't resist.

I like the looks of the Optima. I never got to see them when they were in production, though.

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LOL, no prime on the optima. The shadow had many coats and sandings, but I got a little heavy with the black it seems.

It's big for an estes kit, and slightly underpowered with a D12. They're fun to launch on small fields. But the rocket is a bit fragile for it's size. I'm thinking of making a Blue Tube version with a 29mm mount.

The Optima proved to be an ideal rocket to test fin flutter failure. I built a modified one to take an I motor to try to determine what would fail. With the permission of the RSO (he was informed it was designed as a test to determine failure mode and would most likely fail under power,) it was launched with no one else set up on the pads and strong warnings to keep an eye on the flight.

It was a heart stopping flight. Not because it failed, but because it waited to fail until just before burn out and I started to worry that it wouldn't fail at all. There was a lot of confetti. Enough larger pieces were recovered to permit close inspection and the best I could determine was that the fins had failed from flutter outboard of the fillets.

The I motor was chosen to provide sufficient boost to eliminate the possibility of weather cocking and resultant high angle of attack. This would have manifested itself early in the boost, not at maximum velocity. The boost was one of the straightest of the day, with only slight weather cocking due to a steady wind.

That flight was the culmination of my interest in the flutter failure phenomenon. Afterwards, I wrote an article (and no longer have a copy due to various hard disk failures, moves and a divorce) that appeared in the Tripoli magazine in the mid '90's. It was republished in that magazine at least once.

If anyone has a copy and can scan it, I'd appreciate getting it.

Optima is a great model for adding cluster power. Inboard if done before the original model is built, External pods if after being built stock as I did...

Flys Great on 4-D12 clusters (D12-5 in the core and 3 D12-0's in the pods LOL!
Hope you enjoy yours as much as I have mine

Peter Olivola said:

The Optima proved to be an ideal rocket to test fin flutter failure. I built a modified one to take an I motor to try to determine what would fail. With the permission of the RSO (he was informed it was designed as a test to determine failure mode and would most likely fail under power,) it was launched with no one else set up on the pads and strong warnings to keep an eye on the flight.

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Very interesting. I'd also love to see that article if anyone has it.

I'm planning to build one from scratch for 29mm H motors, Possibly for my L1 cert. Any advice on materials for fins, or should I avoid it all together?

The Optima is one of my personal favorites. I never had one when they were actually in production, so I cloned one last year. Being on somewhat of a BT-80 kick, this thing doesn't disappoint.

HLinc had the tubes on special at the time and Semroc had the laser cut fins listed on their site. When I found an extra Phoenix / Executioner style nosecone, it seemed like a great project.

The build was fine although I may have used too much or the wrong type of glue on some of the stuffer tube CR's as you can see the BT-80 contracted (like a waist) around it when it dried. I finished it off with the yellow, white and black paint scheme (one of the variants listed in the instructions) after seeing the Semroc mini-version.

The instructions mentioned orange metal flake decals (and it's neat to see them first hand in your photos), but I couldn't find anything like that so I used bright orange and chrome trim monokote for the stripes. I got the actual Optima decals from Excelsior (Gordy), but this photo was taken before I had them.



I've flown the Optima a lot on BP D's and E's (nice slow takeoffs) and even a composite D for fun, but I can't wait to try some larger reloads in it. Did the Shadow come with an E9 length mount or was did it just list the E15 as a recommended choice?

Landshark said:

I've flown the Optima a lot on BP D's and E's (nice slow takeoffs) and even a composite D for fun, but I can't wait to try some larger reloads in it. Did the Shadow come with an E9 length mount or was did it just list the E15 as a recommended choice?

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Very nice clone. It's been my favorite rocket for some time. Big, but still transportable. It flies well in smallish fields. I found some metal flake vinyl in sheets on ebay, by the foot. Grabbed green, orange, blue, and chome which is more of a dull metal. I really like that yellow/white/black combo. I was thinking black and green for my third optima style rocket I'm currently cloning (bluetube would be the fourth).

Here's a shot of the Shadow all painted up. Not as nice as I'd like, but it's good from ten foot away. I received the kit on 6/4/97, had it built by 6/6/97, and finished painting her on 6/5/11

(window was probably not the best place to shoot a black body, opps)


EDIT: Just checked on the engines. Both my Phoenix and Shadow were made for the E15's. From the size of the old spacer to use D's, compared to the new spacers I have from my (new) Mean Machine and E9's, it looks to be about 1/4" too short of a mount. Wasn't even aware there was a change. Bummer. Another thing I noticed, the new E9's and D12's I have seem thicker than the handful of old D12's I have. New ones go about halfway into the old rockets before jamming up. (wonder if those old D12's are still good)

DizWolf said:

Very nice clone. It's been my favorite rocket for some time. Big, but still transportable. It flies well in smallish fields. I found some metal flake vinyl in sheets on ebay, by the foot. Grabbed green, orange, blue, and chome which is more of a dull metal. I really like that yellow/white/black combo. I was thinking black and green for my third optima style rocket I'm currently cloning (bluetube would be the fourth).

Here's a shot of the Shadow all painted up. Not as nice as I'd like, but it's good from ten foot away. I received the kit on 6/4/97, had it built by 6/6/97, and finished painting her on 6/5/11

(window was probably not the best place to shoot a black body, opps)

EDIT: Just checked on the engines. Both my Phoenix and Shadow were made for the E15's. From the size of the old spacer to use D's, compared to the new spacers I have from my (new) Mean Machine and E9's, it looks to be about 1/4" too short of a mount. Wasn't even aware there was a change. Bummer. Another thing I noticed, the new E9's and D12's I have seem thicker than the handful of old D12's I have. New ones go about halfway into the old rockets before jamming up. (wonder if those old D12's are still good)

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If they were stored properly the old D12s might be good but I wouldn't try them in anything your not willing to see blow up. I've experienced a few catostrophic failures will some older motors, mostly D12s.

EDIT: Just checked on the engines. Both my Phoenix and Shadow were made for the E15's. From the size of the old spacer to use D's, compared to the new spacers I have from my (new) Mean Machine and E9's, it looks to be about 1/4" too short of a mount. Wasn't even aware there was a change. Bummer. Another thing I noticed, the new E9's and D12's I have seem thicker than the handful of old D12's I have. New ones go about halfway into the old rockets before jamming up. (wonder if those old D12's are still good)[/QUOTE]

As long as you didn't store you D12's in a envoriment were the temp could vary wildly.....Like an unheated garage or outdoor shed. They should be fine.

I've been flying BP motors purchased in the mid to late 60's for years. As Long has they haven't been heat cycled, and are used in ambient air temperature within 75° of the hightest temperature to which they have been exposed they will work just fine. If older then the mid 80's you may want to cut an x in the clay cap as they sometimes become so hard they wont break at ejection

Naw, just sat in my room since about 1997. Between 50 and 90 degrees.

MarkII said:

Was your Optima primed? :duck:

Sorry, I couldn't resist.

I like the looks of the Optima. I never got to see them when they were in production, though.

Click to expand...

And one day later, I get the joke. Lol. Very nice, I think you just named my next optima

I'm looking to downscale two Optima rockets (63% (using BT-60's)), one in the white nose-to-seam/black seam-to-rear paint scheme,


Bill Eichelberger's? Optima

However, I'm also intrigued by Landshark's Optima's black/white/yellow paint job. A quick search shows that landshark hasn't been active on the forum for some time, so perhaps somebody knows more about these paint schemes.


Landshark's Optima

Since the downscaled body tube is longer than 18" I decided to make things simple for myself, I downscaled the lengths of the original to keep the seams in the same location.

I'm presuming that the yellow extends from the seam of the lower tube down to the rear of the rocket, but how far down does the black extend (from the joint with the nosecone)? It doesn't look like the rocket is divided into 3 equal lengths of color (and Semroc's mini-version doesn't have a ratio that looks the same).

Thanks
Jim
.

Hey Jim...I just replied to you privately (I'm still around but a new addition to the family has kept me from flying a lot).

I think there were several different "stock" paint schemes that Estes mentioned or showed in their instructions and packaging. Mine was a clone, so I don't remember offhand if I followed the original instructions or if I
just eyeballed it. I think I probably tried to just figure what "looked" right and then went from there, but if you want, I can check tonight and take some measurements.

Actually, here are the instructions:

https://www.spacemodeling.org/jimz/estes/est2035g.tif

Mine actually looks like the bottom paint scheme, but I did the stripes on the tail like the top two. Hope that helps.

Love the Optima though. Totally a hoot to fly, especially on AP motors. Best of luck!

Hi Elliot,

Thanks for sending the link to the .tif's my computer refuses to open JimZ's .tif's when I try to view them from his site.

In looking at the paint schemes on the .tif, I can't see anything that says something like "paint the first X inches black". So, I'm more inclined to go with your eyeballing version (scaled). I'd love to get the measurements.

For the nosecone, I'm planning on using Semroc's BNC-60V
https://www.semroc.com/Store/scripts/prodView.asp?idproduct=2154
I've yet to run the mod though OpenRocket, so I don't know how much (if any weight) will be needed to make the rocket stable. I'm currently using the (non-Big Bertha) nosecones found in the Estes NC-60A pack as place holders. For engines, I'm planning on 24mm engines (C-11/D/E). The rockets will get 1/2 moon baffles to protect the parachute.

I'm planning on 3/32" thick fins, because that is close to scale accurate, and (once papered) plenty strong.

I've become a big fan of through the wall fins, so both front and back are going to get that treatment. Optima decal from Excelsior. I've got some scrap mylar from my Mercury Atlas(s) for the silver decals. I have some retro-reflective vinyl film for the band of color (I'll be using red rather than orange (it'll save me $15.00 USD). An added advantage to retro-reflective film... If it gets hung up in an orchard (it's happened to me before (see my signature file) I can use a light to help me find it after dark.

I'm doing my build report over on YORF. So, please feel free to check in.

Thanks for the reply!
Jim

I've never seen anyone do the royal blue/ light grey scheme. I may try it on my next one.

I did a couple of downscales and just kinda eyeballed it.
https://www.rocketryforum.com/showthread.php?28567-BT-60-Optima-downscale&highlight=optima

I think I figured it out...
The rocket's (original) length is composed of 3 body tubes, and the nose cone. The upper body tube is 11", the two lower ones are 14 3/16", and the nose cone is 8 3/16".

It would make sense to me that the upper 11" of the original is the black portion, then you have your silver and orange decals just below the joint of the center (white) section, and yellow below the seam of the center and bottom body tubes. Scaled 63%, that makes the upper 6 15/16" long tube black, the next tube has 8 15/16" painted white, and the last 8 15/16" painted yellow. Since 28 3/8" scaled 63% is less than 18" (comes out to 17 7/8"), I was able to make the lower section out of one body tube length.

I cut my parts some time ago, but set it aside while I was waiting to see if the PNC-60AC nose cones I ordered to arrive to see if they would be long enough (they weren't). When I was looking at the rocket last night, I had my nose cone (dry fit, thankfully no glued parts yet) on the bottom of the lower tube. This explains why I was thinking there was a need to mask and paint the black section off from the white.

Thanks for looking.
Jim

Tonight Landshark measured his rocket for me... Turns out my assumption was incorrect (yeah, I know how to spell assume).

Landshark's Optima Clone's paint job is as follows.
Black overall 14 7/8" (14.875")
Nose Cone 8 3/16” (8.125”)
Black Body Tube 6 3/4" (6.75")
White 18 3/8" (18.375")
Yellow 14 1/4" (14.25")

Thanks Landshark!

DizWolf said:

I've never seen anyone do the royal blue/ light grey scheme. I may try it on my next one.

I did a couple of downscales and just kinda eyeballed it.
https://www.rocketryforum.com/showthread.php?28567-BT-60-Optima-downscale&highlight=optima

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Mike Rohde did his in some thing like that blue/grey scheme. It doesn't show up well in this picture.



Or this one.

Looks pretty neat. I'll try to avoid the second photo

DizWolf said:

Looks pretty neat. I'll try to avoid the second photo

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Would be best to avoid the second, I still haven't put it back together since that day. Also, I won't fly it with the E12 anymore (that's what is pinwheeling in the lower part of the photo).

Ah, well at least it looks like you got a good ejection.

I've considered going bigger or composite in an estes built optima....but I think a D12-3 just about nails it. I was thinking about using composites on the next one I build, but I think I'll just built it stock. Well, 2 of the 3 stock.... the third one...well I wont ruin the surprise.