Replacing CA hinges
 

I just removed a rudder from my pattern plane and was going to replace the broken CA hinges. The wood at the hinges has been soaked with CA with the last hinge. Can I replace the hinge in the same spot and still have the same strength, or should I move the new hinges to a new locations? I haven't tried to remove the old hinge halves yet, any hints on removing them?

Thanks, Mitch

Replacing CA hinges
 

Rehinge in a new location.

If you try in the original locatoin, you're liable to cut yourself, and you'll curse trying to cut a slot that is straight in the dried CA soaked wood! [img]i/expressions/face-icon-small-happy.gif[/img]

Replacing CA hinges
 

I've got the GP Foker Dr1 ARF. n the rudder, you have NO choice when replacing THE hinge (yep, just one large CA hinge, full hinge-line.. its just 2.5 inches)

You CAREFULLY slide a hobby knife along the original hinge into the wood on each side. Use a 1/32 drill to go dwn the ends of the hinge. Tweezers to grab and pull it out. This does work.

Then the slot has to be prepped for the new hinge... I used a nail file (emery board) to clean the slot and widen it. I slid in 2 pieces of 1/32 balsa and slid the new hinge between the balsa fillers. Then CA'd the whole mess together. (20 drops of thin CA EACH side on this long hinge)

I'm not looking forward to having to replace the hinge when it fails again.... It'll probably mean a new rudder and tailpost. But this does show that you CAN get the replacement hinges in the original location and get decent results.

Replacing CA hinges
 

This is an ideal opportunity to replace the hinges with something better.
On my planes, I use kevlar thread in a figure-8 pattern at 3 locations for a rudder, say.
I drill 4 1/16" diameter holes about 3/32" apart.
After stiffening one end of about a foot of thread with glue and a fat knot at the other end, it's passed thru the vertical. Then thru the slot between the vertical and rudder, and thru the rudder. Back thru the slot, and into the vertical, generally in the same hole it started with.. then back thru the slot and another hole in the rudder, so there's maybe 6 to 8 "8"s".
A little glue on the ends..snipped when dry.
The holes can go thru the surfaces where the old CA strips are already
installed.
This is very handy when the hinge at the bottom of a rudder gives up the ghost, while the other hinges are still OK.