Papering balsa/ply Fins... A foolproof method

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If there's a TTW fin tab, use an Xacto to cut a slit to prevent the paper from lifting up.

Not sure if I'm correctly picturing what you mean here...If I'm trimming to a border, would I not just do the border around the tab? Where does the slit go?
 
Not sure if I'm correctly picturing what you mean here...If I'm trimming to a border, would I not just do the border around the tab? Where does the slit go?

I edited in some images into the OP.

Basically, the slits are indicated in red in this image below:

 
OK. One thing I am a bit confused on. Does the paper wrap around the edges or just go to the edges? If it just goes to the edge, I would think it'd be better to shape the fins after papering them.

I'm assuming the ca is to seal the edge of the paper and the exposed edge of the balsa. The same way you seal your nosecones.

Somehow I missed this question...

You trim the edge of the paper close to the edge of the fin, then sand it to "cut" the extra off (it also fuzzies up the edge a little, which will allow it to blend in with the wood fibers). Next you seal it with the CA to bond the paper permanently to the balsa. If you try shaping the fin after applying the paper, you may find the edges lift a little (especially if you sand it in a way that makes it want to peal off the edge), and any balsa dust that gets into that space may ruin any chance of the adhesive rebonding to the balsa without having to peel it back and reapplying some glue.
 
I edited in some images into the OP.

Basically, the slits are indicated in red in this image below:

You are awesome and I owe you a beer.
But I will give you a laugh:
This morning I was in the grocery store and thought, "hmm. They carry glue sticks, but I can't remember what kind K'Tesh recommended, and I know there was one kind that was terrible. I'm sure it wasn't anything as basic as this Elmer's Glue-All stick. Ah well. I'll go home, see what he recommended, then order it on Amazon or something..."
...
"...Oh. Well, poop."
 
You are awesome and I owe you a beer.
But I will give you a laugh:
This morning I was in the grocery store and thought, "hmm. They carry glue sticks, but I can't remember what kind K'Tesh recommended, and I know there was one kind that was terrible. I'm sure it wasn't anything as basic as this Elmer's Glue-All stick. Ah well. I'll go home, see what he recommended, then order it on Amazon or something..."
...
"...Oh. Well, poop."

I'll take a Henry Weinhard's gourmet Root Beer (I don't drink the other stuff (more for you)).
 
I'll take a Henry Weinhard's gourmet Root Beer (I don't drink the other stuff (more for you)).

We'll send that along in your care package... Rockets, motors, scale (<--lol) and now root beer :D

Cash and interpreters, you're on your own...
 
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I'm thinking about trying this for the first time on my Estes Pro Series II Star Orbiter. It has a 29mm motor mount and balsa fins. I just know that I'll get a wild hair one day when the weather is great and stuff an H in there, so I might as well add some decent strength to those fins from the get go.

My question is about shaping the fins. I'm thinking about rounding the leading and trailing edges, but not sure if I should do it before or after applying the paper. I read some people wrap the paper around the leading edge on rounded fins, but I don't understand how to get a nice paper finish of the trailing edge at that point. Does anyone have any pointers for doing rounded edges?
 
I'm thinking about trying this for the first time on my Estes Pro Series II Star Orbiter. It has a 29mm motor mount and balsa fins. I just know that I'll get a wild hair one day when the weather is great and stuff an H in there, so I might as well add some decent strength to those fins from the get go.

My question is about shaping the fins. I'm thinking about rounding the leading and trailing edges, but not sure if I should do it before or after applying the paper. I read some people wrap the paper around the leading edge on rounded fins, but I don't understand how to get a nice paper finish of the trailing edge at that point. Does anyone have any pointers for doing rounded edges?

For me, I shape first, then paper. That way, after the paper is applied, I can sand it just a little to feather the fibers into the balsa before sealing (thus eliminating the sharp edge of the paper/wood joint). Also, if you shape after adding the paper, there is a chance you could peel the paper up while shaping it, and that can cause problems with getting it to stick back down again.
 
For my first attempt at papered fins, I am building a canted motor Screamer that has large, simple balsa fins. I used a 1-piece wrap that uses the leading edge as the wrap point. I just placed 2 fins on the paper leading edge to leading edge, and separated them by the the thickness of a fin, then traced and cut them out. I spread white glue roughly with my finger, then used a wooden popsicle stick to squeegee and level the glue to a thin film. Then attached the paper to the fin and squeegeed the paper tight to the fin with a metal ruler with a slightly-rounded edge. Worked like a champ. A couple places needed a little glue under the edge, but it was minimal.

The key is to lay the paper on a larger paper towel and squeegee the glue from the center to the edges, pushing excess the glue onto the towel. If you miss any spots, just use the glue already on the stick and squeegee it over the thin spot. I plan to seal the trailing edge with CA. We'll see how they paint up.
 
I'm thinking about trying this for the first time on my Estes Pro Series II Star Orbiter. It has a 29mm motor mount and balsa fins. I just know that I'll get a wild hair one day when the weather is great and stuff an H in there, so I might as well add some decent strength to those fins from the get go.

My question is about shaping the fins. I'm thinking about rounding the leading and trailing edges, but not sure if I should do it before or after applying the paper. I read some people wrap the paper around the leading edge on rounded fins, but I don't understand how to get a nice paper finish of the trailing edge at that point. Does anyone have any pointers for doing rounded edges?

I like to shape first. That way the exposed part is also smoothed by the paper. I don't know if any data, but it seems that the trailing edge at least could do with some extra strength. The need for both of these (area to smooth and benefit of extra strength) are increased when the trailing edge is tapered, though this is not the case.

I would wrap the paper around the rounded leading edge (as you said) and for the trailing edge, glue the paper onto the flat surfaces, then cut it with scissors to overlap a little in the middle. Glue the paper smooth (the overlap will be knocked off) and press it with a fingernail (lightly enough not to damage anything) into the pocket formed by the other half of the paper. (if there is any) CA, then sand smooth.
 
I would wrap the paper around the rounded leading edge (as you said) and for the trailing edge, glue the paper onto the flat surfaces, then cut it with scissors to overlap a little in the middle. Glue the paper smooth (the overlap will be knocked off) and press it with a fingernail (lightly enough not to damage anything) into the pocket formed by the other half of the paper. (if there is any) CA, then sand smooth.

I like this idea. It will be nice and strong, and also have a great finished look with the paper wrapped around both the leading and trailing edge. Now to try and execute it! Wish me luck!
 
I like this idea. It will be nice and strong, and also have a great finished look with the paper wrapped around both the leading and trailing edge. Now to try and execute it! Wish me luck!

Good Luck!

Oh, and to clarify: I fold the paper over the leading edge of the fin, then cut the paper out so that it covers both sides with one sheet.
 
I just posted a couple pictures of my papered fin method and the final result on "the other forum" (post #9). I make a one-piece paper fin cover and wrap it over the leading edge. I do not worry about covering the square edges, I just treat with CA to seal the balsa. I use the Elmers large glue sticks, which I have found in the crafting section of Hobby Lobby. They seem to stick paper to balsa very well, but I do wick CA onto the paper edges if I think there is any chance of lifting.

https://forums.rocketshoppe.com/showthread.php?t=16423
 
As with any method that people may decide to try, remember to experiment with it on scraps of balsa first. I'm happy with my method, unaltered, but you may find that an alternative idea that works better for you.
 
I'm thinking about trying this for the first time on my Estes Pro Series II Star Orbiter. It has a 29mm motor mount and balsa fins. I just know that I'll get a wild hair one day when the weather is great and stuff an H in there, so I might as well add some decent strength to those fins from the get go.

My question is about shaping the fins. I'm thinking about rounding the leading and trailing edges, but not sure if I should do it before or after applying the paper. I read some people wrap the paper around the leading edge on rounded fins, but I don't understand how to get a nice paper finish of the trailing edge at that point. Does anyone have any pointers for doing rounded edges?

Burrito roll it! If you start at the trailing edge, about a 1/4-1/2 inch back, wrap around the trailing edge then to the leading edge and back down to the very end of the trailing edge where you started, you get a nice sealed seam protected from the airflow. Be sure to squeegee the glue as you go.
 
Another option for papering fins and stiffening body tubes is this stuff:



Apply with water on both sides of the fin, clamp flat and let dry. Soak with thin CA glue for extra stiffness.

For a body tube, roll on at an angle from one end to the other. Wipe with water to activate the glue. Let dry. Works great!
 
I've been papering in the last month with good success, but I don't seal the edges with CA, I use white glue. It softens the fibers and allows you to burnish the paper in. I don't use a glue stick but instead white glue in a thin layer via a credit card as squeegee. After I apply the paper, I use an old credit card to smooth the paper.

If all goes well, the paper then covers the previously sanded curved non-roor edges of the fin
 
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White glue works, the downside is that it doesn't sand well. Since I got my fume-free BSI SuperGold thin CA, I switched from using TB2 to that for my fin edges, mainly for its better sandability. I find I'm able to get a more perfect blend between the edge of the paper and the bare fin edge that way.

When I do glued paper (vs. adhesive labels) I always use white glue for the papering itself. I hate glue sticks.
 
ALWALYS PAPER YOUR FINS.. YOU CANT BEAT THE ADDED STRENGTH AND SPEED!!
 

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A lot of great ideas in here. The only problem I have is after papering my fins I find little pot marks in the paper from the pot marks (divids) in the balsa. I agree on the earlier posts that after you CA the edges the paper soaked in the CA inward about an 1/8 inch or more. This dose show up through the paint job. I like the Elmers all purpose white glue for papering. Yes a PITA messy but good results. One thing I noticed about spray paint the paper fins is that it draws the paper fiber upward. Even after a light sanding and redcoat it did it again. So this time I painted the finished fin with CA before painting giving it a light sanding. That seamed to take care of the fuzziness.
 
A lot of great ideas in here. The only problem I have is after papering my fins I find little pot marks in the paper from the pot marks (divids) in the balsa. I agree on the earlier posts that after you CA the edges the paper soaked in the CA inward about an 1/8 inch or more. This dose show up through the paint job. I like the Elmers all purpose white glue for papering. Yes a PITA messy but good results. One thing I noticed about spray paint the paper fins is that it draws the paper fiber upward. Even after a light sanding and redcoat it did it again. So this time I painted the finished fin with CA before painting giving it a light sanding. That seamed to take care of the fuzziness.
I don't mind a small hint of wood grain on my fins. I think a person could add wood filler on top of the paper and sand that smooth but you would have to be careful and it would take a lot more work.

I've done a few rockets by putting the wood filler on the balsa and sanding it smooth, no paper involved. I got pretty good results but not perfect. I decided I was going to paper for strength and it gave me acceptable appearance for a rocket that I'm building to fly. I did have the idea that I could use wood filler on the balsa, sand it smooth, and then glue the paper on. That would give a smoother surface under the paper so should give really good results, but probably at more work than I wanted to do.

I round the fin edges except for the root, then I put wood filler on the exposed wood and sand it smooth. Where paper meets wood filler I can get some fuzzies. I'll put 1 or 2 coats of primer on the finished model and sand it, this takes care of the fuzzies.
 
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