Im doing the CG on my new plane and was wondering if its ok to epoxy the lead weight to the plywood or bulsa? It shouldn't come loose right?

That is how I do it.
In fact I use #10 lead shot. $10 for a 25lb. bag and enough lead to last a life time of modeling.

Absolutely. I do it all the time.

Ken

have you thought about move some of you gear around so you dont need to add weight???

You haven't bought any lately, have you? It's more like $28 for a 25 lb bag today.

if i use lead in a firewall or hard wood section i will use screws to secure it in place,ive also found out if you have tight places or small pockets like under fuel tanks ect, that you can use plumbers putty it sticks to the wood pretty good and is very pliable will conform to whatever shape you stuff it into.

Broad question because it depends on where and how you epoxy the weights, to what degree of vibration the weights are subjected to, and how they might be braced for "G" forces that happen in maneuvering flight.

Epoxy one side of a weight to wood in the engine compartment, and you will soon have a bomb drop. Same goes for those that glue a tire-weight strip of lead to the fuse. side in the tail section. Where it done go? [:-]
Epoxy weights within a scrap-wood box in the frame work and they will probably stay a long time. Lead shot wrapped in thin plastic such as Saran Wrap, stir in a lot of epoxy and then epoxy within structured areas will conform to the structure and hold in very well.
My preferred weight is the flat round fishing weights found where fishing supplies are sold even such as Walmart. They come in different weights and are marked. It is easy to drill a hole in the center and bolt them in. Epoxy can be used for back-up.
Do not depend on the wire line-attachment loop to hold them in place. THAT HAS been tested. []

Good luck.

I would not epoxy anything that has any weight to balsa (such as CG adjustment lead weights). I would find a place that is made with plywood or at least reinforced somehow so that the weight doesn't rip the balsa out. Other than that, epoxy weights in place seems to make sense to me.

CGr.

LOL no I have had this bag for quite a while.

AAAAHHHH!!!! Heavy metals! Poisonous epoxy resins! Run away before it gives you the cancer!!!


Okay, sorry. The media made me say that. In seriousness, I have epoxied lead weights (grudgingly) where needed on my planes to achieve CG, and haven't had any come loose yet. I don't know if it matters much but I only use 30min. or longer epoxy for this, and I build up a little fillet around the edges of the weight so the epoxy is bonding to a greater surface area. Problem is, when you glue it in TOO well, you damage the wood taking it out......don't ask.

Grudgingly for sure. My Tiger 120 requires over 16 ounces of lead in the nose to make the CG. Not good. But, it flys great in spite of all that darned useless weight.

GOOD LORD![X(] About half of my parkflyer fleet weigh less than the lead in your Tiger!! All relative, though...

Yeah.. I was not a happy camper when I finished that plane and checked the CG. And that's with a new OS 1.20 AX up front. A friend has one with an OS 1.60 FX and he too needed a lot of nose weight to make it right.

I complained to Goldberg, but their only answer to me was "what would you like us to do about it?" My answer was FIX IT for the next guy!!!

I was at Bass Pro Shop on Monday and they charge about $60 for 25 pound bags.

I can't believe how much prices have changed. I just did a quick search online and the cheapest I could find was over $40.
I bought 2 bags years ago. I still have alot of the first bag left. Glad I got it when I did.(seems like lead prices are going the way of gold and copper?)

Wow, alchemy works after all!

You are looking in all the wrong places...

Visit your local garage, ask to dispose of some of their used tire balancing weights.

I chisel out a mold in a piece of 2 x 4 and then melt the lead in an old tin cup and pour carefully. (it's hot!)

This way you can custom make a weight to any spot that is required. [8D]

A friend of mine bought a 120 Tiger ARF and yeh buddy, that thing took some lead to balance. But what a sweet plane. He did break one of the landing gear blocks on a landing that wasn't perfect, shall we say, but by no means what you would consider a gear buster.

I use lead shot and epoxy. I like the shot . I can measure the amount needed very accurately. I like to pour the epoxy into a cormer, hardwood or even balsa ( if its not too much lead) and then pour in the lead. IF you are worried about the wieght coming loose, you can give the wood some tooth by partially drilling tiny holes in it.