sheeting foam wings

which glue is preffered for sheeting wings no cap strips ca epoxy spray (3m77) or other. sheeting a rd-1 wing thanks to all answers alan

This is what I do. It was taught to me by none other than Mike Pratt, of SIG MAGNUM fame. Use extra slow cure epoxy, sometimes called laminating epoxy, which is rather thin. Mix and spread on the sheets. Use a credit card to scrape ALL the excess epoxy off, so that just a tack surface is left.
Stack and let dry 24 hrs.
I did my Magnum this way and the wing came out very light.
Try it you will like it. Mikey did!
Brian

Godzilla wrote about using Titebond Polyurethane glue (Lowe's), with much the same method of application. Lots of weight is needed for pressing the wing skins on, as the stuff foams. A light mist of water on the foam core was mentioned. I'll try to find the thread and post a link. Maybe somebody has the thread bookmarked? Steve

>This is what I do. It was taught to me by none other than
>Mike Pratt, of SIG MAGNUM fame. Use extra slow cure epoxy,
>sometimes called laminating epoxy, which is rather thin. Mix
>and spread on the sheets. Use a credit card to scrape ALL
>the excess epoxy off, so that just a tack surface is left.
>Stack and let dry 24 hrs.
>I did my Magnum this way and the wing came out very light.
>Try it you will like it. Mikey did!
>Brian
I'm with Brian,I have just finished expoxy bonding 1mm balsa to my Magnum cores, I added two LG 1/8 lite-ply ribs,I used just under 1oz of resin for both wing panels, they weigh 4oz ready for LE & TE & Tips.

Good flying

I, personally, like the epoxy method as mentioned by Brian also. If done right, it is lighter than the contact cement, probably stronger, and it will not separate in the hot sun.

Pic of the press used for 'epoxy bonding'

Good flying

Hi Alan,

While I like the Z-POXY method of sheeting cores we used 3M 77 on several planes, including Aaron's first contest plane, an RD-1. 10 years later and the sheeting is still firmly attached. Nothing beats the speed of that method. My SV-11 was done with 3M 77 and after two rebuilds, and now a whole new fuselage, the wing is holding fine. It's 11 years old.

ANY method you use: Be sure to vacuum the cores after you do a light sanding to them!

Bill <><

gentlemen thank you for the replies on sheeting wings will go with epoxy. will be finished with silkspan and dope. now need to build a press thanks again alan

Just another opinion....

I like Godzilla's Titebond Polyurethane glue idea.

Here is the theory according to Bob Hunt, one of the down sides to foam wings is the tendency for the little beads of foam to separate from each other over time caused by the flexing of the wing in flight. This results in the skin no longer being securely attached to the foam. A foam wing gains most of it's strength from the skin/foam bond and as more of the little beads separate the wing becomes less rigid. This doesn't necessarily result in wing failure but maybe the airplane just doesn't quite fly as well this year as it did when it was new.

Now I haven't any scientific data to prove this one way or the other but if it is true, I would think the Polyurethane glue would give you an advantage over epoxy or contact cement in that the Polyurethane expands to contact more of the little beads of foam in the wing.

Makes sense to me anyway....

>Just another opinion....
>
>I like Godzilla's Titebond Polyurethane glue idea.
>
>Here is the theory according to Bob Hunt, one of the down
>sides to foam wings is the tendency for the little beads of
>foam to separate from each other over time caused by the
>flexing of the wing in flight. This results in the skin no
>longer being securely attached to the foam.

Never, ever, ever, ever, seen that.

I think Windy's Tradition is foam. I think it has something like 10,000 flights on it.

I did not know Bob had any planes that lasted long enough to get worn out.

If bead separation is really a problem, then there's always the blue foam and the pink foam..

I have had real good luck with the PICA GLUIT Sandable Alphatic.....very easy to apply, and, when dry, very, very little weight gain.

And, like the label says, sandable.

Windy and Scott Smith produced a video about a dozen years ago where both the 3M-77 and epoxy methods were used........ Scott was a proponent of epoxy, whereas Winfred likes the spray glue. Both panels were the same weight when done, 'near as Win could figure. They went on to build a PROWLER with the halves...I wonder what happened to it?

See Ya

I've gotten the best results (I think) using Windy's method of creating wing skins, and then using 'Zilla's Titebond polyurethane glue method.

Windy made a tape last year where he and Elliott Scott made wing skins that were perfect - no gaps between the joined sheets making up the skins whatsoever. I was able to duplicate their results without any difficulty just by following the tape. If you're making foam wings, I highly, highly recommend this tape.

I prefer the Titebond over spray glues because (1) I think the Titebond is easier to work with and (2) I have better (i.e. more precise) control over how much glue goes on the wing skins. If you think you've put too much glue on the skins with the Titebond, just wipe it off. (As an aside to this, I've found that the best - and cheapest - way to 'squeegee' glue off the balsa is with "Magic - the Gathering" cards...)

While the spray glue is a good method, I always feel like I've applied way too much glue after using the spray.