Tip-to-tip papering fins

[Woody's Workshop]

Try "HERE"

That's one nose cone I been keeping an eye out for forever, or a Estes Aries SST kit at a somewhat reasonable price.

 

[Woody's Workshop]

You are welcome.
One always needs at least 6 builds in the process.
Some things only takes 10 minutes, then 24 hours to dry.
Can't get nothing done only working 10 minutes a day, so ya grab another bag and RIIIIIIIIIIIIIIIIIIPPPPPPPPPPPPPP it open.
And if painting gets backed up due to weather, well, it just keeps going.

Woody,

Thanks for giving me some ammo with the spousal unit... Your picture showed her that it's normal to have many projects in many varying stages of completion... right up to having been primed!

fm

 

[K'Tesh]

One always needs at least 6 builds in the process.

6 builds in the process?

You better get your keyboard checked... the zero looks to have gotten stuck.

Here I'll retype that for you...

One always needs at least 60 builds in the process.

 

[Woody's Workshop]

Just givin forever-metal ammo for use on his wife.
Mine I would guess is close to 30, with several to start after the 1st of the year.
Painting has been shut down due to extreme cold, so builds continue.

Got me curious, so I counted.
4 in the Build Process
6 waiting for Primer
2 in the Paint Process
8 in Primer ready for wet sanding
1 wet sanded ready for paint
1 in for repairs
1 in for total rebuild
1 on deck, have the parts, Estes K-37 Scrambler
Have an SR-71 and Quest Courier, not sure all the parts are there
Estes K-6 Ranger after the Scrambler; TBD scratch build or Semroc Kit, Depends on money, have parts.
40 plus kits in a box and on the wall waiting to get started.
So to sum it up, right now I have 24 in process.

 

[AfterBurners]

Is that where you lay down a sheet from the tip of one fin to the root, then along the body tube to the root of the adjacent fin, then to the tip of that fin?

No, never heard of that in LPR, usually fins are papered by folding over the leading edge and go from trailing edge to trailing edge before the fin is attached to the body. but this is a clever concept, and probably would work with paper, if you could solve the warping problem. Usually the moisture in the glue can warp the balsa, so you have to keep it flat under some heavy books or bricks while the paper is drying. Not sure how to tackle that on two adjacent fins that are already on a body tube.

I use spray adhesive when papering fins. After it dries I soak the fin with thin CA. I never had any issues with warping. I'm sure the same process would work with the paper over lapping the root edges.

 

[K'Tesh]

Just givin forever-metal ammo for use on his wife.
Mine I would guess is close to 30, with several to start after the 1st of the year.
Painting has been shut down due to extreme cold, so builds continue.

Got me curious, so I counted.
4 in the Build Process
6 waiting for Primer
2 in the Paint Process
8 in Primer ready for wet sanding
1 wet sanded ready for paint
1 in for repairs
1 in for total rebuild
1 on deck, have the parts, Estes K-37 Scrambler

And a partridge in a pear tree!!!

 

[TangoJuliet]

Is the TB3 worth using or should someone stick with TB2? I'm a sigbond guy myself but maybe i should switch...

fm

I've never used the Sigbond, but TBII works just fine for me.

 

[Forever_Metal]

Just givin forever-metal ammo for use on his wife.
Mine I would guess is close to 30, with several to start after the 1st of the year.
Painting has been shut down due to extreme cold, so builds continue.

Got me curious, so I counted.
4 in the Build Process
6 waiting for Primer
2 in the Paint Process
8 in Primer ready for wet sanding
1 wet sanded ready for paint
1 in for repairs
1 in for total rebuild
1 on deck, have the parts, Estes K-37 Scrambler
Have an SR-71 and Quest Courier, not sure all the parts are there
Estes K-6 Ranger after the Scrambler; TBD scratch build or Semroc Kit, Depends on money, have parts.
40 plus kits in a box and on the wall waiting to get started.
So to sum it up, right now I have 24 in process.

I was at a grand total of 26 around Sept time-frame. You couldn't walk anywhere without possibly bumping into a rocket. When you consider a build complete? Assembled? Primered? Painted and decaled up?

fm

 

[Woody's Workshop]

When you consider a build complete?

Decals on, any flaws fixed, laundry in.
Ready to stick an engine it and wadding and in full dress uniform.

 

[Andy Greene]

Decals on, any flaws fixed, laundry in.
Ready to stick an engine it and wadding and in full dress uniform.

after its flown and recovered.

 

[Woody's Workshop]

Not for me.
Chances are if I go up 1000', I don't get it back.
Fact of 46 years of trying.
Where I have to launch, the Tree Gods take more than their share.

after its flown and recovered.

 

[ep29030]

With low power models, I've done two layers of typing paper in the fillet area of fins. I made one layer a little larger, so their is a stair-step edge. Makes it easier to get a smooth finish if that matters to you. It adds a lot of strength.

Have also done tip-to-tip fiberglass with 2 layers of 2-3 oz/yd plain weave fiberglass and epoxy. Again, I made one layer slightly larger than the other, so their was a stair-step edge. So first layer came short of fin tip and length by about 1/2 inch on every side, and second layer fully covered tip to tip area. This is solid: did this one Mega-Mosquito, as those huge fins would pop off too easily. Had a couple of landings on asphalt and gravel drive--fins never popped loose. It works.

 

[Woody's Workshop]

Don't know if this matters on rockets.
But when repairing fiberglass, 3 layers are typical.
Larges pieces goes down first, work towards smaller layers.
When you grind (sand) to feather the edges you can sometimes ware threw a larger layer at the edge a smaller layer underneath.
Thus, the strength stops at the breach.
I've worked on vetts, semi's and boats.
But something small as a LPR it probably doesn't make a difference.

 

[Jack Hydrazine]

I have published a 3D model of the PNC-50S nose cone that you can download for free from Thingiverse and print on a 3D printer.
https://www.thingiverse.com/thing:4899740

 

[KarlS]

Yep, happens every time I fly my Estes Goblin with the stock streamer. Some designs are just prone... that's what I keep tellin' myself anyway.

The stock streamer is much too small. Use one 4" x 40", Mylar if possible.

 

[BABAR]

I'm in the middle of building a Goblin and thought about this thread. I decided to paper the fins and leave the paper along the root side long. I then folded the paper along the root edge and glued everything with titebond. Then added fillets using titebond.

View attachment 307191

It isn't exactly like the tip-to-tip method but I'm hoping this will prevent the fins from popping off. Murphy and his laws always end up with my streamer rockets finding the hardest random thing to hit in a grass field. I'm also building it to where I can clip in a streamer or parachute to leave my options open on that front.

I have used this and it is a great idea to speed up fin attachment, larger surface area means that while the drying Isn’t faster, you get sufficient tack soon enough to hold it while you move to next fin.

I’m with @neil_w on this, I don’t think it is stronger than a regular glued balsa to body tube fillet.

one thing that might make the joint to tube fin WEAKER for paper fins is if you paper allMathenia way to the root edge. I am not talking about papering over the root, everybody should know that’s a no-no. But IMO you should not only and off the glassine (and maybe even scuff the cardboard if the tube a bit to expose the fibers, although this is a little tougher to do EXACTLY on the fin attachment site, but you SHOULD also leave a bit (say 1/8”) of balsa EXPOSED at the root edge of the fin on both sides where it meets the body tube. So no paper in the joint. The fillet itself covers the paper edge, so not a cosmetic problem.

so the joint is tube-glue-fin, not tube-glue-PAPER-fin. Don’t get me wrong, I think glued paper is great for both strengthening fins and cosmetic appearance (eliminates or at least reduces need to filling balsa grain), but paper makes a lousy adhesive attachment point.

may be lack of experience on my part, but aside from really high temperatures softening the glue, I’d be surprised to see a fin “pop off” on a straight body tube/balsa fin filleted joint itself. UNLESS The glassine wasn’t sanded off, I would expect either the fin to break OR the outer paper layer to delaminate and break off before the joint itself failed.

OTOH, if a fin DID pop off (as long as it did so on LANDING and not it in flight) I think I rather WOULD have it come off clean at the joint, as most likely had it NOT popped the stress would have broken the fin or delaminated/tore the paper at the attachment point, as both of the latter failures are a bit more difficult to fix.