[NRV Rocketry] Fiberglassing HP Rockets: Good Videos, Tips or Tricks (for body tubes and nose cones?)

[Thomas Weeks]

First, why do people use fiberglass on the body tubes on high power rockets?

Well, after reading how other flyers who have launched my same "LOC Hi-
Tech"rocket on full J motor but have seen them shred when passing mach-1 -- I 
I decided it best to go ahead and glass my new 2.6" (diameter) bird:
http://www.rocketryforum.com/showthread.php?36225-LOC-Hi-Tech-shred-J350

Well, not being that experienced with fiberglassing myself (having only done 
it one other time), I was looking for some really good tutorials on youtube 
and surprisingly didn't come up with that much. So I juts proceeded with what 
little I knew. Wow.. I learned some hard lessons/tips that I'll share further 
down.

But first.. 

MY QUESTIONS:
Q: Anyone here have any good tricks-n-tips or HOWTO videos, links, etc they 
would suggest?

I still have some specific rocket glassing questions on:
* the recommended use of alcohol for thinning the epoxy
* what weight of glass-fabric to use
* when to use > 1 layer
* can you glass a plastic nose cone? (if so, how?)
* final finishing tips (top coat? sanding/wet sanding, etc)

MY TIPS:
A few fiberglassing tips (aka lessons) I have to share after learning them the 
hard way today are:


1) Epoxy Cure Time is Critical:
BE SURE to check the set-time of the epoxy BEFORE you start mixing and 
applying the epoxy and glass fabric. Never use 5min epoxy. 15 is ill advised. 
Use 30 or even 60 minute for more time to do a good job!  I decided to use up 
the last of my old 15-minute epoxy today for this project, and BARELY rushed 
and got it all smoothed out before it setup on me. </whew!> I had t oadd more 
alcohol TWICE to keep it from prematurely setting up on me!  I later used 
finishing epoxy on another part of the rocket, but I hear that "West System" 
is the best epoxy to use for nice HP rockets:
	http://www.westsystem.com/ss/
	(Bob?)

2) Set Up A "Glassing Station":
Set up a nice glassing station like this, as it helps immensely:
	http://www.facebook.com/photo.php?fbid=3602061510552&l=706a387e07
Once you have the epoxy mixed, glass fabric half applied, body tube balanced 
on a broom stick, and epoxy starting to gel... it's too late to try to set 
something up. ;)  I found that I could use the box that the vendor shipped my 
rocket in, as it was juuust the right size. :)


3) Alcohol for Smothing out Bumps:
As you finish hte last few inches of glassing a BT, quickly start turning your 
work looking for bumps, lumps, globs and stray glass threads before it gets 
too tacky to fix them! Wet your gloves liberally with alcohol and "smooth" the 
surface, rub off any lumps or bumps, work out air bubbles and ensure the ends 
of body tubes are wrinkle free.


4) Rotate Piece Until Set:
Keep turning your project until it has mostly gel or set. Otherwise, you can 
get pooling and drips (that will need to be sanded off later) nad lopsided 
coverage. I have heard of people reprovisioning motorized rotisseries for this 
purpose.


Anyone else?

Tweeks
p.s. I know that fiberglassing is a specialized area of knowledge for Bob (who 
just rolled back into town).. so I am half hoping that he'll share something 
useful. :)
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