Anyone used fishing line for hinges. I saw that somewhere I think an RC site...……………

But if you do use Spiderwire, keep in mind it is really thin stuff, and wicks CA.
I tried it on a few test pieces and was afraid it would cut through the balsa. That, and it really wanted to wick the CA, so keep it far from the edges or the hinge line stiffens up! I probably drilled the holes too big. If I tried again, I'd just stab the wood with a heavy T-pin rather than the puny drill bit I used.

I prefer a slightly heavier cotton/polyester thread just to keep it from cutting the wood. A drop of CA at each hole is all it takes to keep the thread from moving like a saw. Jump over to CEF...the remnants of the Scientific P-40 shows how tough a good, sewn hinge can be. I tore the tail off that bird, but the elevator stayed on the stabilizer. The BHM Mosquito also held up to a pretty rough "landing."

Come to think of it, this has been a banner 12 months...I wrecked my two favorite planes! Yeesh.

Mr. Dave,

I'm a Frankenstein-hinge guy. But what you suggest has me re-thinking my hinge lines.

Are you suggesting that the drilled line of holes goes on the seam, or glue line between the balsa and spruce? That would make sense since the Spectra would be pulling against the spruce, and not into the balsa.
Then the stresses on the Spectra get spread out along the entire hinge line by the laminated edges. If that is the case, then it means I can actually make a few, smaller hinges along the hinge line, instead of one longer run per side of the tail. They will appear to be less visible.

Since I build smaller models, I'm thinking about trying this with bamboo skewers instead of spruce. They are already pretty close to the thickness of my surfaces.

Personally, I just use a large needle. No need to drill a hole when you can just push a needle through the balsa.

And now that someone said "Bamboo skewer", I think I'll try that great idea!

Jerry

PS: On my RC ship......... (No pretty points anyway!)

Porsche_Jim,

Yes, I think you are visualizing what I am trying to describe. I tried to find a close-up photo to show you...but no luck. (I could text you a photo if you'd like; just leave a number in the private message place.)

I guess I should have clarified what I mean by Frankenhinges. This is the kind that spaces a bunch of single wraps all the way down the hinge line. You used to see them in the photos of the 1950's and 1960's on sport planes, rat racers, etc. I think they are overkill and buh-tugly. That said, they work fine, I'm sure. If you combine them with the thick, hairy Kevlar line that sounds so techie to some, then you have a monster turbulator that probably makes your control surfaces, well, turbulent. I'm sure that has appeal to some of the aero guys....

Instead, as you have deduced from my less-than-the-best description, if you glued a spruce, bamboo, or other harder material along both edges of a balsa stab and the elevator where they normally meet, and you drill holes directly opposite each other thru the glue-line, then you can pull the Spectra wraps fully tight. I actually use a small pair of needlenose pliers to cinch it up and avoid cutting my fingers. Along a small 1/2A elevator, I put in two hinges per side. Even on a .40-powered Quickie Rat I only use three "hinges" per side--just like I'd do with Klett plastic hinges. That means you only drill 4 or maybe 6 pairs of holes to do an entire split elevator. The holes don't need to be big. Just enough to thread three passes of .011" diameter line thru.

You don't need much of a spar. I've even used the thin basswood strips from the hobby shop. If you are worried about weight, just use a little softer balsa for the surfaces themselves--now that you have a spar to help carry the bending loads.

I'm not the paint and finish guy around here, but I have seen these sewn hinges relieved into the wood surfaces and then filled and painted over. They practically disappear.

There's lots of ways to do things and people develop methods that suit their tastes and skills. I'm just explaining a way--and the materials that go with it--that appeals to me.

The Divot