simple concepts

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Rex R

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they say that the simple concepts can be the hardest to grasp. like the 'more is better' when applied to glue...I know that one gave me trouble when I was younger :), gluing fins gave me all sorts of 'fun'. was thinking of that yestereve when I was gluing fins on my Big Bertha and it took me some 3 hours or so (including filets and drying time) to complete thanks to two things one, the house is dry, and two, I didn't use much glue. over doing the glue is messy and increases drying time considerably.
any other simple concepts that have given you problems?
Rex
 
Importance of Fin Grain relative to attachment point.
Fin grain parallel to attachment point/long axis of rocket :no:
Fin grain perpendicular to flight path of rocket :smile:
Thing is, while you are building it, it looks fine, it's that first landing that tells you you messed up!
 
Importance of Fin Grain relative to attachment point.
Fin grain parallel to attachment point/long axis of rocket :no:
Fin grain perpendicular to flight path of rocket :smile:
Thing is, while you are building it, it looks fine, it's that first landing that tells you you messed up!

Isn't it "grain parallel to leading edge of fin"?


Steve Shannon
 
Depends on the fin. For instance, in symmetrical trapezoidal fins - /_\ - a fin grain perpendicular to the tube works as well.


My simple concepts:

-Cleaning off my fingers before putting the paper on. (While papering fins)

-Not kinking body tube.

-Preventing fins from falling off while gluing.
 
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Just recently on my Formula200, I was ready to slide the MMT into the booster. My foremost mental note was: "Don't get the threaded rod in the way of the fin slots!" Simple, right?

Then, when I actually did slide the MMT in, I got so caught up in unexpected problems that I paid no attention whatsoever to the orientation of the T-rods. Sure enough, once I had that bad boy jammed in there, I noticed that I had blocked the fin slots. :facepalm:

So I had to stop everything, drive to the HW store, buy a 2x6, drive home, get out my sawhorses, get out my power saw, cut the 2x6 from 8' down to 5', put everything away, ask my wife to hold the booster while I pounded the MMT back out with the 2x6 and a hammer.

You can be sure that the second time, I got thing lined up perfectly.
 
keeping your fingers clean and dry while doing fins?
Rex

I use the liquid glue rather than gluestick. Gluestick peels of after a while in my experience, but other people somehow manage to get good results. Depends on what works for you, I suppose.
Neither work perfectly for me, but skill issues are easier to fix.

Sometimes the little glue boogers get stuck on the paper, finger gets stuck to paper then the damp paper tears, etc.

Still need to perfect the technique...


Oh, and I'll add another one:

Accidentally breaking things while trying to fix the little mistakes.
 
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