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

[Maier.chris]

Tweeks - look for "Jim Jarvis carbon fiber" in Senior Google's magic locator machine.

This place used to host the article I borrow from heavily but appears to be offline now....  (side bar: Maybe you and I should try and help them out TWeeks)

http://www.rocketryplanet.com/content/view/3640/38/

I incorporated many of Jim's tactics and tips in to the fiberglassing of existing rockets vs. making my own carbon fiber tubes as Jim does.

I'm actually gassing a rocket right now, I'll post a few pictures and how I'm doing stuff - I can't say my way is right or even a good way, but you are welcome to it none the less.

I don't use standard epoxy for my glassing - I use aeropoxy stuff as per Jim's recommendations.  Main reason is that I'm working with 5.5" and 7.5" rocket tubes most of the time and extended pot life is required.  Current project is a 4.0" madcow baterang 

http://www.avtcomposites.com/cgi-bin/commerce.cgi?display=home


Chris



On Dec 31, 2012, at 2:52, Thomas Weeks <tweeksjunk2 at theweeks.org> wrote:

> 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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