On a 40 size plane - how many drops of CA do you put on each hinge (approximately). I've read 6 drops per side (total 12 per hinge) and I've seen as few as 2-3. I end up getting CA all over everything trying to get 6 drops per side, so I figured I ask everyones input. Thanks!!

I use 4, each side. Haven't had a failure yet.

Disclaimer: claims of the builder are comments for the use of their plane. We accept no liability in the event of following the directions and any subsequent failure

6 does sound excessive however

Nuker

Same here, 4 each side

I don't count them. I just keep going until the Ca no longer wicks into the hinge. 4-6 sounds about right. Of course it depends on how big the drops are that come out of your bottle! If the Ca gets on your monocote, keep a rag ready to wipe it off immediately.

Tom

I use the Hobbico Hinge Tool with CA blades and drill a 1/8th inch diam hole down the middle of the slot. I then clear the the slot and hole of wood fragments and drop CA down the slot and hole. I saw this in RCM magazine and it was in the instructions of one of my kits. I have used this method a long time and no failures yet. The Hobbico Hinge Tool is great but you need a guide slot to get started otherwise it will bounce all over the place.

I had this question not too long ago running through my head so I decided to give these hinges the test.

I got a couple of scrapes of wood(about the size of a trailing edge and an aileron) and hinged them together with the ca hinges. I found that 2-3 drops worked just about the same as 4-6 drops when I gave it the old pull the two pieces apart test. These hinges really hold! They will tear out pieces of the wood slots when they decided to give.

Try this test and find out for yourself, you'll feel a lot more confident about ca hinges afterward.

BTW - when you CA hinges, have a rag and some acetone handy. It can remove fast cured CA very easily when it (inevitably) runs all over your brand new perfect finish. Just wipe it off quickly. Once it is cured just keep at it gently until it is all removed. Acetone will not attack the outer part of Monokote or Ultracote, but excessive rubbing can scratch it. Wipe off any haze that develops with Windex or similar

If you put a light coat of petroleum jelly around both surfaces to be hinged (NOT ON THE HINGES OR IN THE SLOTS!), the excess CA will just ride on top and clean-up is a snap.

I agree with Greenboot,

It's not essential to put an exact amount of drops - just add until it no longer wicks into the slot.