Scratch - Der Red Max (Upscale) {Scratch} Original Design / Scratch Built

Contributed by Joseph Michel

Manufacturer: Scratch
Style: Upscale
(Contributed - by Joseph Michel - 12/10/02)

Rocket PicBrief:
HPR Der Red Max, 2.458X upscale. 48" parachute recovery.

Construction:
All materials are PML. I used 4" Quantum tubing, cut and slotted for me by PML. The body tube was cut to 20.8 inches, while the fin slots were 4.6 inches long, 3/8" from the end of the tube. The fins and centering rings were made from 3/16" ply. The fins were fiberglassed for extra strength. The rocket has a 29mm phenolic motor tube that was cut to 12". A PML motor retainer was also used. The nosecone is a PML PNC 3.9. Recovery is via 12' of tubular nylon with a 48" PML parachute.

This was a fairly easy rocket to build. It makes a good scratch project for a newbie. (like me!) Construction proceeded using standard HPR techniques. I built a special shish-ka-bob rack for construction and painting. This rack allowed me to work the fin fillets without having to fuss about the position of the rocket. I could rotate the rocket anyway I needed to have it. Internal and external fin fillets were both 30 min. epoxy. After about 10 days of sanding and filling of the fins and fillets, it was finally ready for primer. I laid on 3 coats of Rustoleum sandable auto primer, sanding in between each coat. Next, I laid on 3 coats of Krylon Banner Red Gloss. After drying for 24 hrs. I masked off and painted the black stripe around the top on the body tube with Krylon Gloss Black.

Rocket PicAfter allowing sufficient time for the paint to dry, I applied the decals. I had Tom Prestia of Tango Papa decals make the 2.458X upscale decals for me in self-adhesive vinyl. Tom's decals are excellent! Applying them was easy. After all the decals were on, I applied 2 coats of Rustoleum Crystal Clear Gloss. The clear does not react with this type of decal at all, and gives the model a nice glossy coat.

Flight:
Well, I planned to fly this model on G-40 and G-80 motors. I quickly found out that "Big Red" was just too heavy for that. I believe that this "heavy weight" condition is due to the heavier PML airframe and the fact the DRM has HUGE fins. I also used 3/16" ply for the fins, so that did not help either. I have not flown this rocket yet due to motors being unavailable. I plan to fly it on a H-128 with 4 sec delay.

Summary:
Pros:

  • The Der Red Max is awesome, no doubt about it!
  • While upscaling one of these beauties is not a terribly original idea, not everyone has one either!

Cons:

  • Cost! I spent about $195.00 total building this model. This includes paint, supplies, decals, etc. If you just want to fly, buy a kit - it's much cheaper.
  • Weight. If you build one based on my construction, consider using G-10 or 1/8 ply for the fins.

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