Damnathius

Have you ever spent the time to get the gap in your control surfaces to be nearly non-existent while using CA hinges? Yeah, me too...

Only to have a BIG drop of CA come out of the glue bottle and run for several inches down your "gap"? Yep... so have I. Tried to soak it up with the corner of a paper towel? That paper towel often doesn't get into the gap, which leaves a bit of CA to make for a very stiff hinge line!

Well, I've come up with a method to soak up that run of glue. I usually use Great Planes CA hinges on all of my planes, and have come up with a use for those left over substandard CA hinges that often come with ARFs.

Keep a few of these handy when installing CA hinges, and when the occasional "mishap" occurs with the CA glue, take one of these hinges and insert it in the gap between the surfaces a few inches away from the hinge, and quickly pull it through the excess CA all the way to the hinge, then pull it out of the gap. This makes for a nice, clean hinge job, and you don't have your covering glued together between the surfaces! It's amazing how much excess glue these things will soak up.

I will even use them when I didn't make a glue boo boo, just to keep it clean and remove any excess glue I might not see.

Works great for me.

Dave

Steve Lewin

Neat dea though I think I prefer scribing a wax pencil line on the hinge to stop the CA getting to the hinge line in the first place. It seems to work even on the furry CA hinges.

Steve

CafeenMan

I think he means to prevent the glue from running along the hinge line though, not necessarily just the hinge itself. Sounds like a good idea.

rajul

My Feedback: (58)

Ca might wick along the hinge line, even if you drop the proper amount right on the hinge due to capillary action. apply some vaseline along the hinge line, or slip in some wax paper in the hinge line. using a ca hinge to soak up stray ca is a good idea, but I guess it has to be done quickly or it will stick....

Damnathius

I've tried putting lubricant on the trailing and leading edges, and it also works, however, if you don't remove the glue, the glue is still there, right?

As far as being quick about pulling the hinge through, I have never had it try to stick in the gap. I don't know why... Perhaps it's the limited surface contact.

Just sharing a tip that works for me.

rajul

My Feedback: (58)

Hi damnathius, I'll remember this tip when I run into a similar situation. Thx........

Kaos Rulz

...........That's a great idea. I like it and will try it on my next kit. Thanks!

CafeenMan

Just another case for not using CA though. If you use epoxy and put it in the slot then you don't have to worry about stuff like this.

cruzomatic

My Feedback: (17)

What happens now if there's dried CA still in the gap? How do you get rid of that?

MinnFlyer

My Feedback: (4)

I would like to mention one little detail here...

Gentlemen, PLEASE do NOT try to have "No Gap" when using CA hinges!

CA hinges need a SLIGHT gap so they have room to flex. Without this gap they are MUCH more likely to FAIL!

Please read:

http://www.rcuniverse.com/reviews.ph...ew&reviewid=55

Pay particular attention to the 4th paragraph in the "Important Notes" section at the end.

Remember, it is much easier to seal a gap than to replace a CA hinge, or worse yet, to replace a crashed airplane!

planecrazy101

Maybe a little off topic, but I use a covering matching crayon to draw the line on the hinge. Makes them almost disappear.

Damnathius

Thanks Minn. Please note I said "nearly".

cruzomatic

My Feedback: (17)

But what happens now if the damage is already done. I'm thinking I may not have done my setup correctly. Can the hinges be cut or removed and start over again?

Damnathius

If your surfaces move relatively easy, there is no damage. With a triangular leading edge on the surface it is very hard to get it "too close"... Really.

Edit:

If need be, CA hinges can be removed more easily than might be expected. Simply cut the hinges between the surfaces to remove the control surface, and using a sharp #11 X-Acto, very carefully cut on both sides (top and bottom) of the nylon portion of the glued hinge stubs. This will separate the nylon and allow it to be pulled from the slot. Then you can insert a new hinge.

cruzomatic

My Feedback: (17)

thanks,,

MinnFlyer

My Feedback: (4)

Next rule of CA hinges:

Once you have cut them off, either put new hinges along side the old one, or replace them with a different type of hinge. Here's why:

Ca hinges MUST be installed with THIN CA. Thin CA works on a capillary principle, that is, it NEEDS to be used on a porous surface (which is why it sticks so well to skin). But if thin CA has been previously applied to an area, the pores are sealed, so if you get any bond at all, it won't be a good one!

Damnathius

I don't mean to be argumentative, but...

CA bonds metals and plastics pretty well. It also sticks well to itself. We're probably just using different brands.

SHARK

I just had this stuff happen to me. I'm finally finishing up on an old Sterling Stinson Reliant kit and when I glued the ca hinges for the ailerons I pushed them real tight and must have gotten some ca running along the hinge line. They were so tight the servo could hardly move them. I kept wiggling them thinking they would get better and finally realized they were no good, so I cut them off and am going to use hinge points instead. I'm starting to think I don't like ca hinges real much.

MinnFlyer

My Feedback: (4)

I don't mean to be either but, not all CA is alike. Did you ever notice that medium and thick CA is also called "Gap Filling"?

After you have chopped out an old hinge, you will no longer have a tight fit. Sure, it might seem tight but it is only grabbing in some areas, it's not a clean, surface to surface union, which is what thin CA needs to work properly. Thin CA won't do diddly in even the smallest of gaps. Combine that with the fact that the pores have been sealed, and you're an accident waiting to happen.

CafeenMan

Has anyone mentioned using epoxy yet?

ProfLooney

Nope not yet. One thing people dont realize is that epoxy is not fuel proof. Yes a lot of people use it in their firewall area to protect the wood but usually it is painted over thus protecting it. Also when it is put on it is usually put on fairly thick. Glow fuel will soften epoxy and thus cause failure I have seen many a firewall come flying off planes due to being slowly eaten away by glow fuel. There are several compatability charts out there one I can think of off the top of my head is the Harry Higley book i think its the There Are no Secrets one and it has a glue compatability chart. CA is better for hinging that epoxy for 2 reasons. 1: it is more resistant to glow fuels and 2: it soaks into the balsa even the thick will soak in some. Epoxy is a surface adhesive which just mechanically bonds two surfaces without soaking into the wood. if is it thinned way down with alcohol it will soak in some but it is mainly the alcohol that is doing the soaking in. Dad is a furnature restorer and has a wood shop and I got to learn a lot about wood glues used through the furnature industry and that transfers to ours. I havent used epoxy in over 20 yrs I use stuff like hide glue, titebond, or polyurethane glues and have never had a failure and use CA for my hinges.

Joe

CafeenMan

I've got to heartily disagree with you on this one. I use epoxy to fuel proof every one of my firewalls and almost never paint over them unless I'm painting the aircraft. It's held up fine without a hint of decomposing in any way at all. I brush it on and while brushing I warm it slightly with a heat gun. Not hot, but warm enough to become watery and flow. I also never ever use anything faster than 30 minute epoxy and prefer 2 hour epoxy.

CA IS NOT nitro proof. In fact, Nitro is a DEBONDER.

If you thin epoxy that would explain a lot of the problems. Alcohol in any quantity, no matter how pure, will interfere with the chemical curing process as well as cause the glue to shrink, make it rubbery and then brittle and who knows what else. Epoxy should never be thinned, but thinning epoxy has been covered in detail in at least two other threads.

Slow drying epoxy will soak into the wood. Probably not as well as a solvent based adhesive, but used properly I trust it 100%. My planes don't fall apart in the sky and even when I crash there are never failed joints - just broken parts.

I don't use a lot of epoxy, but I do use it for firewalls, landing gear mounts and I used to use it for laminating but I use polyurethane glue now.

Anyway, I was referring to using epoxy to glue in hinges in my last post - not general uses of epoxy.

As long as your planes stay together in the air, then they're strong enough, right?

ProfLooney

well i havent used epoxy like i said in 20 yrs but I am going by several compatability charts not personal experience other than seeing a lot of epoxied firewalls fail. now since i didnt build them there may be something else at work but since i see it regularly i can only assume that the charts were right. Personally I like to pin my firewalls to my sidewalls with small dowels cant be too careful. The other fact is I dont fly glow anymore I use gassers so I dont worry abt the nitro on my CA.

Joe

birdnest

When I do CA hinges, I do three things to keep the glue from getting in the hinge line:

1: Use one of those thin, capillary tube tips on the CA glue bottle.
2: Rub some waxed paper over the monokote surfaces in the hinged area before assembling the parts.
3: Keep a bunch of strips of newspaper about the size of a bandaid at hand to stick in the hinge line and absorb any extra glue.

Peter

bentgear

Epoxy is fuel resistant, not fuel proof.
Ed M.