Build Questions...???

[Steward]

O.K... Can't put it off any longer...
I'm going to start building my Estes "SHADOW" that I've been sorta putting off...
Couple off questions to get out of the way first...
Would it be worth it to go ahead and upgrade the motor mount to 29mm? Will it be strong enough for F's or small G's???

I've never used rail buttons before... this rocket only uses the "Estes" paper type centering rings... so what should I do about mounting the buttons??? I'd rather not just glue them... how about a small block (smooth edges) inside to hold the screw or nut on???
Or... just use a thicker CR to screw into...
Either way it's got to be done during early assembly...

Really... I quess I'm so unsure... I might as well get someone to build it for me...LOL.... (joke.... get it???)

Really...really...Thanks alot... TRF rocks as always....!!!

Steward

 

[Habu]

I've been planning a 29mm Optima so I'd like to see how you do with this. For mine I have cut ttw fins for added strength.
Post some build pictures if you can and best luck with this project.

 

[Rick James]

I'm not familiar with the Shadow... but I have done a few of these upgrades - so I'll share what I did.

First thing is replace the balsa with basswood. For me that's the rule #1 for MPR, basswood fins. (Plywood is overkill in my opinion). TTW is a must. As for centering rings - it depends on the width of the CR. If it's relatively small, and epoxy fillet around the ring will essentially fill the space and paper is fine. If not, I go to basswood for these as well.

I've never used rail buttons - I don't have acess to a rail except at club launches. But if I want to launch it on my own I need a launch lug. I generally always replace the lug with a brass tube - either 1/4" or 3/16" - I have both size rods.

I did upgrade the Optima - a beautiful rocket. However, after one flight on a G motor, the body tube showed signs of stress failure. I would strongly recommend longitudal supports of some sort. It is a long rocket with a lot of mass to push. I'll probably fly it again on an F - someday it will completely fail, but it wants to fly.

Hope this helps,
Rick

 

[lalligood]

Rail buttons are surprisingly easy to install. Drilling a hole & attaching them with CA or some epoxy will be more than adequate for a MPR bird. I have attached them on rockets that weigh up to 5 pounds like that without even a hint of being problematic. As long as they are on the rocket straight, you'll be good to go!

HTH,

 

[Habu]

I'm fairly certain that the Shadow and Optima are the same except for graphics.

 

[North Star]

The Optima (yes, it is the Shadow now) was the first large rocket I built (1994 - it's still one of my favourites) and has only flown 8 times - always in good conditions (sentimental reasons )
It showed signs of stress after the first 4-5 flights with 'rippling' along the spirals and after a heavy landing the tail end also kinked (so much that I back filled it with foam).
The tube is thin and I think any serious power, especially the faster propellants like blue thunder, would soon trash the rocket. Estes tried to make the structure strong in compression by using a long stuffer tube but the airframe tube in between the couplers is just a bit weak. Internal stringers would help - but cloning with LOC tube would be the easiest 'upgrade'.