Strengthening internal structures
 

Hi there,

Generally when I build a kit, I reinforce the landing gear area, firewall, wing holding blocks, etc. with triangle stock and an adequate amount of epoxy. Right now I am assembling a GP Big Stik 60 ARF and some of the areas - namely the wing holding area - need some reinforcement, but there is very little room to put triangle stocks in there. My other thought was to use fiberglass cloth & finishing resin for reinforcement, this way I could do a better job covering a larger area.

With that backdrop, here's my question: will glassing yield the same end results as, say in this case, adding triangle blocks in terms of reinforcment? If so great; if not, when do you use glassing as a reinforcement in the structure (other than joining wing halves?)

RE: Strengthening internal structures
 

The Fiberglass tape and epoxy is better than nothing but the triangle stock is better

Be sure and thin epoxy the tank compartment

RE: Strengthening internal structures
 

ppkk,

There's another method of reinforcing. Here's a repair How-To I wrote for Epo-Grip Adhesives sometime ago where filets were used for strengthening out of adhesive. The adhesive is their #30 Paste which mixes up like petroleum jelly it does not run or sag allowing you to place it in areas not easily accessible otherwise and its much stronger.

www.epogrip.com/pdf/epo_grip_arf_rebuild.pdf
www.epogrip.com

Newton Supply Company 800-888-2467

RE: Strengthening internal structures
 

Steve - this is interesting, I will give them a try. Thanks for the tip.

RE: Strengthening internal structures
 

The gorilla glue/elmers ultimate are GREAT arf beefer-uppers ! I always go in and reglue with them. They do look ugly after they swell up, and I know some people don't like that. Also you need to experiment with them to see how much it runs before it swells, and how far it puffs up. Once you get an idea it is a very useful tool. The nice thing is for some jobs you can run it down in to the iffyglue joints, position the plane to let it lay so the glue stays where you want it, then it puffs out leaving a tough but flexible gusset, just like adding tri-stock.


I had one friend get upset over this type of glue because he didn't experiment, he just applied a bunch of it and walked away, well it ran down and expanded in places he didn't want it..

RE: Strengthening internal structures
 

I should have mentioned if you need the adhesive to "flow or float" into a hard to get-to area Epo-Grip's Clear Paste product does that job well.

As the product cures it heats up into a semi-sag consistency. That allows you to mix up the product apply it to an area then control its movement by tilting the project your reinforcing allowing it to float out into a perfect filet. The Clear Paste takes about 7-10 minutes to cure once mixed depending upon workshop temperature.

RE: Strengthening internal structures
 

Steve - I just ordered the #30, I'll see how well it works. Sounds like a pretty solid yet easy patch work. It sounds like I can accomplish what Clear Paste does with regular expoxy or finishing resin, so I am OK there. The petroleum jelly consistency is what I am after.

Foodstick - thanks for the tip. While I have a bottle of Gorilla Glue, somehow I keep forgetting about it. In this case however, it wouldn't do what I am looking for. But now that you mentioned it, I'll just get the bottle out of my drawer and put it on the table so that I start using it before the bottle expires on me!

RE: Strengthening internal structures
 

Received the #30 yesterday and just tried it. It's a little pricey but this is great stuff! Almost exactly the same consistency as Petroleum Jelly - maybe slightly thicker - even the same color. Very slow cure properties gives you plenty of working time. I'll definitely have these in my glue box going forward!

Execellent service by the company by the way, very quick shipment.

RE: Strengthening internal structures
 

any chance of picture of what you were trying to accomplish.....i have some filets that i would like to do as well as reinforcements.
thanks
Joe

RE: Strengthening internal structures
 

Look at post #3 above by Steve, this is how I got the idea to begin with. He has a good write-up about this.