I decided to lighten the plywood fins on the Der Bigger Red Max.
Tricky to do after installation but a little perserverance with the Dremel tool paid off.
If I skin them with balsa they will be too thick, so I'm going to fill the voids with 1/8" balsa and apply a paper skin.

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DBRM plywood fin voids filled with 1/8" balsa and paper covering applied.

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I planned to skeletonize and skin the 4" kit with thin balsa or 1/64" ply when I bought it several years ago, but I never got around to building it. I wanted to see how light I could make it and how "low and slow" I could make it fly. I was considering sanding the NC to make it thinner and lighter, and peeling the inside of BT, all for the sake of making the build interesting.

I still have a scratch built 4" DRM I built over 20 years ago that I used to fly on 38mm EX motors so there is no point in repeating myself with another heavy HPR rocket.

Let us know what your final weight is compared to a regular build.

__________________
I love sanding.

Now that the glue is dry I was able to do a comparison.

The initial assembly was 5 oz.
Cutting the fins brought it down to 3.5 oz.
The balsa inserts, glue, and papering took it up to 4 oz.

Not a significant gain for several evenings of work but I did have fun trying.
My concern was that there would be too much weight on the aft end for the finished length.
The cone is a 10" balsa unit and it weighs in at 2.5 oz., so it may be just right when completed.

The slotted tube is now permanently attached to the fin can and I have started applying fillets.
I made a cable tonight to attach the shock cord and the nose cone has been sanded.
Just a little more bodywork and it'll be ready for paint.
I still need to make some decals, so I'll be working on them while the paint is drying.
Finished length is just under 36 inches and weight as shown is only 8 ounces, much lighter than I expected.

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I now have four models going simultaneously.
No doubt contributing to my sense that I'm not getting traction on any of them.

DBRM - We had a nice enough day here to get some paint on this one. I made launch lugs earlier in the week and managed to get it in primer by last night. We're expecting a snowstorm tomorrow so it will have plenty of time to dry.

Drei Maxxx - This one is still in sealer and fillet mode but I hope to have it in primer by the end of the week.

Maxi Alpha 3 - I wanted to properly repair the top of the tube before it goes to paint. It suffered a zipper a few years back and I put a cardboard collar on it as a temporary fix. I removed the collar and peeled off the paint and white glassine layer to get a clean surface. I wrapped a heavy BT-80 coupler with a few layers of wax paper and pushed it into the top to keep it round. A strip of kraft paper was brushed with diluted glue and wrapped around the tube. Another patch was placed on the inside directly over the tear. Just a little filler needed at the paint joint to complete the repair. It's now good as new and the nose fits easily.
It also received some stronger launch lugs at the same time as the big Max.

Enerjet 1340 - I'm building a three fin version so I'll call it the 1330.
I have a bunch of BT-56 nose cones looking for a home and this seemed like a good place to start.
I had a few of Jack Hydrazine's excellent fin cans printed last week so it shouldn't take long to assemble.
My Phoenix Bird already has the original four fin version of the can, so I went with the three fin model this time. Very nice!
Before you ask, it will be 24mm powered. As much as I would like to put the correct 29mm engine in there, I know that if I do I'll never see it again.

I also had some PRP-1G cans printed, so that I too can "Build and fly the missile that destroyed the Imperial Death Star"

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I had this one started for several years, but last summer it became the missile that hunted the sandworms in Dune. It was easier to do the decals.

__________________
Bill Eichelberger
NAR 79563

http://wallyum.blogspot.com/

I miss being SAM 0058

Build floor: Centuri Mini Dactyl Estes - Low Boom SST Semroc - Marauder, Shrike, SST Shuttle

In paint: Canaroc Starfighter Scorpion Estes F-22 Air Superiority Fighter, Multi-Roc, Solar Sailer II Semroc Cyber III

Ready to fly: Estes - Solar Sailer II Semroc - Earmark, Groonie Der V 1/2

I am glad to announce that my Der Bigger Red Max is finished. Mother Nature cut me a break and I was able to apply the last coat of paint late in the week. I'm pleased with the result and must admit I had way too much fun designing my own version of the decals.

Enjoy!

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I really like the Smurf and TIE Fighter kill markings along with the outhouse!

Bob

__________________
illegitimi non carborundum

NAR# 54643 L-1

SAM# 043

AMA# 157091

VRCS# 154

A&P# 42x xx xxxx.

Better than Nessie?

__________________
Bill Eichelberger
NAR 79563

http://wallyum.blogspot.com/

I miss being SAM 0058

Build floor: Centuri Mini Dactyl Estes - Low Boom SST Semroc - Marauder, Shrike, SST Shuttle

In paint: Canaroc Starfighter Scorpion Estes F-22 Air Superiority Fighter, Multi-Roc, Solar Sailer II Semroc Cyber III

Ready to fly: Estes - Solar Sailer II Semroc - Earmark, Groonie Der V 1/2