Foam Presentation Board

[Woody's Workshop]

I was just wondering if anyone has used the 1/4" thick board for fins?
I'm not sure of the proper name for the stuff, but during a school project my wife was unhappy with the dents that occured and purchased another board to complete the school project. Left me with lots of foam board on hand.
I've used a piece to make a fin jig for my V-2, but I was thinking that if you glued another layer of, say poster board card stock over both side and around the ends after shaping, wouldn't that make a good light weight fin?
Now, take in concideration this would be only for the upper end of LPR's. Maybe something in the lower end of the 29mm engines in a normally bottom heavy rocket that would require nose weight using light ply or balsa fins.

Just curious if anyone has used this board in this application, and what to expect as I plan to try it at least once to investigate it's potential.

[RevKeith]

I just got through helping my son with a school project and we used foam board. I too was thinking that stuff has potential for fins. Surely someone has used it on TRF. How about some pics.

[hornet driver]

I've used it for prototyping fins and it works fine for that. I even used it to work out the fin/wings for my Timberwolf, and did glide tests with it. As far as using it for the fins , I think the finishing headaches outweigh any advantage in weight over balsa-----this coming from a guy who just got done building a bondo mold for a rocket with a ton of finish work in it just for the molds So maybe I'm not the right guy to ask ,but I have thought about it. H

[sooner.boomer]

My friend Braz used to make everything from fins to entire gliders out of the cheap dollar-store stuff. My "Aurora" stealth fighter is made out of it:




(very stealthy - flat black doesn't photo well)

I used a strip of typing paper wetted with thinned-out yellow glue on the leading edges. Had to cut relief "darts" so it would bend around curves. Braz would use dowels or square balsa for leading edges.

Just noticed Braz is in the picture, just above the sign. Really miss the old guy!

Non-rocket use: I've made Yagi and log-periodic antennas with cheap foam board and copper foil tape (like what's used for stained glass).

[Woody's Workshop]

Balsa/Dowels is a very good idea on leading and other edges.
Great Hint, Thank You a bunch!

[kenstarr]

I've used foam board on 2 high power rockets, fiberglass covered of course. Bad Battle Axe fins and one other, the Maceys Rocket. Very strong and light weight. on something low powered, probably wouldn't need any reinforcement! Oh yeah, on the Maceys (NOT Macys) rocket, I did use dowels on the edges for strength but not on the Axe.

[Pem Tech]

I used years ago as fin material for an MPR build, it was quick and easy. However, it doesn't seem to hold up well to bumps and dings. Maybe you will have better luck.

[PhlAsh]

Concur with the 'line with dowel' comment. My 4" Red Max upscale waits for warmer weather and some fiberglass over its fins.

[jflis]

Yep...

Decaffeinator and UFFO both use foam core for fins... Great stuff so long as you respect its limits.

jim

[nealkas]

The doweling and a paper wrap should make these surprisingly robust for their limitations.

[rocketguy101]

I have used it for centering rings...this is an "F" power flight...I plan to try a "G" someday (hence the name "Preparation H").

Never tried it for fins...I like the edging w/ a dowel though.

[hornet driver]

My friend Braz used to make everything from fins to entire gliders out of the cheap dollar-store stuff. My "Aurora" stealth fighter is made out of it:




(very stealthy - flat black doesn't photo well)

I used a strip of typing paper wetted with thinned-out yellow glue on the leading edges. Had to cut relief "darts" so it would bend around curves. Braz would use dowels or square balsa for leading edges.

Just noticed Braz is in the picture, just above the sign. Really miss the old guy!

Non-rocket use: I've made Yagi and log-periodic antennas with cheap foam board and copper foil tape (like what's used for stained glass).

I really like the profile of that ,do you mind if I sorta-kinda-maybe a little --copy it a bit? Hate to ask but it's better than outright stealing.

[StefanJ]

A non-modeling use I'd like to mention.

You can get foamcore in colors. I have a couple of pieces of flat gray that I use as a photographic backdrop. I use it to photograph models, parts, whatever.

[sooner.boomer]

I really like the profile of that ,do you mind if I sorta-kinda-maybe a little --copy it a bit? Hate to ask but it's better than outright stealing.

PM me with your email address. I'll see if I can find the rocket, trace and scan the outline, and email it to you.

[jadebox]

"Astron Mike" has built and flown a number of really-cool gliders and other rockets that use the foam board you can get at Dollar Tree and other stores.

http://www.google.com/search?q=%22as...ike%22+gliders

I've used the foam boards to make fin alignment jigs, but not fins themselves.

-- Roger

[Micromeister]

I was just wondering if anyone has used the 1/4" thick board for fins?
I'm not sure of the proper name for the stuff, but during a school project my wife was unhappy with the dents that occured and purchased another board to complete the school project. Left me with lots of foam board on hand.
I've used a piece to make a fin jig for my V-2, but I was thinking that if you glued another layer of, say poster board card stock over both side and around the ends after shaping, wouldn't that make a good light weight fin?
Now, take in concideration this would be only for the upper end of LPR's. Maybe something in the lower end of the 29mm engines in a normally bottom heavy rocket that would require nose weight using light ply or balsa fins.

Just curious if anyone has used this board in this application, and what to expect as I plan to try it at least once to investigate it's potential.

Some brands out there currently Ultra board, Jet-Mount foam board, Gator-foam board and most often widest commerical used "Foamcore".
comes 1/8", 3/16" and 1/4" as Foamcore. others can be had in thicknesses up to 3". Generally a opencell foam sandwiched between to heavy cardstock like paper outer surfaces.

Yes i've used it on a few different models, Odd-Roc's, helicopters and gliders. Fun stuff, surfaces soak up paint making it heavier then balsa, but unpainted or markered pretty good stuff, light and stiff.

[Woody's Workshop]

Stuff the wife got had the Elmer's logo on it, called presentation board.
I think I will try making fins out of it, sliver some balsa for the edges and coat with TiteBond II like I do everything else. Sand smooth and paint.
Only real concern I think I will have from reading everyones posts is keeping the foam core glued to the body tube.
Perhaps I incorperate TTW fins and Epoxy to the engine mount for added strength.
There just comes a time in upscaling, certain rockets especially, that balsa is not really feasble due to the size of the fins.
My first thought was to order up a bunch of 1/32" balsa and cross grain glue to make my own plywood from it.
But when this foam board came to me, I had to ask the question. Would save a tremendous amount of work from the other above idea I was leaning towards.
Thanks bunches everyone, again ya'lls knowledge comes through like the mid-day sunshine.

[Tolppisouth]

I once saw a two stage pyramid rocket built totally with it. A teacher said one of his students built it and it flew.

[sooner.boomer]

I was just digging through my old pictures. Here's a shot of my buddy Braz next to one of his rockets made from a mailing tube, with foam board fins. You can't see the balsa nosecone he turned for it. Flew as well as anything with wood fins.

[Woody's Workshop]

Well, the board was a full 1/4" thick. All I had on hand was 3/16" balsa (thanks to my secrete sante XO) and the Gorilla Glue worked great.
After a light sanding to take down the excess, I used posterboard card stock and used TiteBond II to adhere the card stock, and put 3 coats (all thinned) and let dry. Sanded, used Elmers wood filler and sanded smooth and used another 2 coats of thinned TB II and sanded smooth.
I have just adhered the fin (root edge being the foam board) to the body tube and it works really well. Great adhesion, very strong.
I'd say that the foam board/balsa/body tube process is a light weight, strong fin in the manner that I did it and will work well.
I'll use several coats of unthinned TB II to do the fillets as usual and I believe that this is a good method to use if you need light weight fins to help offset an understable rocket design.
I'll do more info when it is completely finished and test flight has been completed.
But I am extremely confident that this is a good method.
I will weigh each fin and put it into RockSim to get a better handle on the stability factor so I can more accuretly decide what nose weight is needed for the stabilty I demand for this rocket.
Of coarse, pics will be presented.
And if someone is willing to post videos (too much for me to get into) I would be glad to furnish the video to anyone willing to post them.
Until later...