strengthing Estes fins

I haven't built an model rocket in a couple of years and I can't seem to remember how to strengthen the fins. Seems like I laminated it with paper but I do not remember if I use CA(thick or thin) or just white glue?

Also, do you bevel the fins before or after you laminate it? I know I can wick CA into the edges after I bevel it and get a fairly strong edge, but this does not seem strong enough for the whole fin.

TIA

Burt

Reply to
Burt Holyfield
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Why not just 'paint' them with a thin epoxy. It'll absorb into the balsa and it'll really strengthen those babies up.

Reply to
Brian Kosko

I usually just use poster board and Weldwood/DAP contact cement. It works fine, and doesn't add much weight at all. I've found the contact cement joints are usually stronger that the paper itself. You can even print the patterns on the paper before gluing it on.

Mark E. Hamilton NAR #48641-SR

Reply to
Mark Hamilton

Laquer sanding sealer and if you are anal, a wood dowel or spruce strip on the trailing edge for landing strength.

Reply to
Jerry Irvine

my kids and I use a thin coat of carpenters (yellow) glue on the balsa fins, wait until it is tacky, laminate it with 24 lb paper (like inkjet paper) and press it between boards with a heavy weight on top (we use a "penny jar" or a few phone books).

After it dries, we sand the bevels (paper side toward the edge, from one side then the other), then wick CA into the edge. The CA both hardens the balsa edge, and also helps bind the paper edge to the balsa.

lightly sand, prime and paint. This also eliminates the need to sand and fill the balsa.

we have never broken a fin using this method, even when deployment fails.

IMO extending the serviceability of Estes rockets has been a valuable exercise in construction techniques.

- iz

Reply to
Ismaeel Abdur-Rasheed

Cover them with fiberglass while you're at it, it will make it even stronger. Or could always use carbon fiber on it, it'll make the thing very stiff yet light weight. Downside is that it doesnt take impact too well so dont go dropping them from 10th floor. I have tried vacuum bagging (as opossed to pressing them between books or vises) and it seems that when stressed (this is double sided 10oz carbon and 1/8 inch thick balsa) the balsa would seperate from the carbon fiber! Leaving me with 2 very flexable sheets of carbon... whats up with that?

Reply to
tai fu

Any form of "paint" on the surface, be it epoxy, yellow glue, or CA does little to strengthen the fin. TO get maximum bang for the buck (or gram) you need to cover the surfaces with some material. It can be paper, plastic (monokote), jap tissue, fiberglass, carbon fiber, kevlar, silk, or more wood (i.e plywood).

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

Jap tissue is the proven winner here.

Reply to
Jerry Irvine

What is jap tissue?

~Duane Phillips.

Reply to
Duane Phillips

Hard to find/get and a especially good paper quality and specially suited for covering balsa for any aeromodel applications.

Possible sources of info? AMA, SIG manufacturing, and others.

Try SIG first for sure. Montezuma, IA

Reply to
Jerry Irvine

I've laminated my Estes fins with wood glue and the facecard that comes with the kit. Laminate them one side and press flat with something heavy. You could use thinner paper though, as this cardstock process adds .040" to .060" thickness to your fin. Laminating does add lots of strength to your balsa without adding a lot of extra weight.

Reply to
J.A. Michel

The quickest and easiest way is to use Avery peel and stick labels. You can buy it at office supply places like "Office Max" or "Office Depot". It comes in many sizes but the most useful is the 8 1/2" x 11" standard paper size. After you have sanded the edges square and smooth and before glueing, apply a label to one side, smooth with fingers or roller, turn over and apply to other side. Sand bevel on leading and trailing edge if desired, CA edges (except body tube edge). Double glue fin onto body tube. Prime and paint. Finished.

I can cover four fins in less than 15 minutes. Even "Big Daddy" fins.

Karl Perry QUARK, Cincinnati, OH "Flying Pig" Contest this weekend at VOA Park in Westchester, OH

Reply to
KG8GC

Yeah. What exactly is "jap tissue"? That should offend someone :-)

Reply to
Greg Cisko

It's a paper material supplied as covering in small balsa airplane kits (or at least used to be)...

Interestingly, I've recently been seeing a somewhat similar material sold (for way cheap) in general stores as "gift wrap tissue" - I wonder if it's any good with balsa & dope?

-dave w

Reply to
David Weinshenker

For strength to weight, absolutely correct. Which is why my competition BGs are made of contest balsa, then tissue and dope finished.

But for HPR, where you're starting with plywood, might as well go for glass/epoxy or better...

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

It would work, but it's nowhere near as good.

I'm aware of 2 sources for the real stuff: Sig and Peck Polymers.

For more details, refer to

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8.2.13.1 How to tissue a glider

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

Aluminum.

Reply to
Kurt Kesler

I must not be "old" yet because I remembered SIG and where it was located :)

Reply to
Jerry Irvine

YES.

Reply to
Jerry Irvine

I thought you preferred steel.

-dave w

Reply to
David Weinshenker

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