Install SCAT ducting

[trib]

OK, so this should be one of the simplest tasks in building an airplane. I'm trying to get the 2" SCAT ducting, the red kind, to slide over the stub tube on the exhaust heat muff and it's kicking my a**. Are there any tricks/techniques to getting this done without breaking a sweat? I've twist this way and that, pushed, pulled and begged but the tubing and the ducting are still not speaking to each other.

[170 driver]

Did you unwind the wire from the first inch or so from the inside of the scat? It has to be cut off down inside the scat so that it's only rubber going over the heat muff stub.

[Geico266]

I've found it easiest to unwind the spring wire into the scat tubing instad of cutting it off an inch or so inside. If you cut it off inside the wire tends to poke a hole through it. It can be a PITA.

[jetjok]

Unwind about 1"-1.25" of wire. Bend the wire 90* perpendicular to the tube so that the wire is "up" in to the tube. Cut the wire so that there is about .5 inches. Then using pliers, push the wire down into the tube, so that it lays across the wire spiral. This will allow the load of the loose wire to be borne by the spiral, and by having the bend pointing up will keep it from puncturing the tube.
If you do not do this, you will find that the wire wears through the tube in short order.
Good Luck!

[wil]

I unwind about 1.25" of wire also, but bend the wire 90 degrees about 5/8" from the end and back onto and parallel to the length of the scat tubing on the outside. The bent end of the wire is put under the hose clamp and locks it into position.

wil

[trib]

Thankyouverymuch Of course I was trying to get the wire to go over the stub. You learn something new every day, even at this stage of the game with the airplane almost completed.

[az_gila]

Originally Posted by trib

Thankyouverymuch Of course I was trying to get the wire to go over the stub. You learn something new every day, even at this stage of the game with the airplane almost completed.

The wire should go over the stub... otherwise all of the vibration loads at the end of the stub are taken by the cloth material only.

Wil's description above is the best, and by clamping the wire with the hose clamp, the tubing will be fully supported by the wire.

It can be made to look a little neater if you have some excess cloth at the end, and you roll the excess back over the hose so it is under the clamp. Not essential, but it does look a littler better this way.

Ooops... just re-read Wil's post, and I prefer to do it his way, but with the bent end inside the hose.....

gil A