Installing the woodwork & Tail Drive System

Installing the woodwork inside your fuse is the most important thing you will do. There are a couple of things you should do prior to doing any work inside the fuse. The first thing you should do when you get your fuse is to take all the fiberglass parts and stick them in the bath tub. I use dishwashing liquid with one of those scouring sponges (they have one side which has a scotch brite pad attached to it) and wash the outside and inside of all the parts with a warm soapy mix. This will get rid of any release agent which may still be present inside the fuse, or on the parts themselves. Nothing likes to stick to this release agent. After that, I dry it as much as I can and set it aside for a day to dry out.

The next day, I take a piece of 80 grit sandpaper, and sand the entire area inside the fuse which a former is going to be applied. You just want to take the gloss off the fiberglass. I then sand all the outside seams down as flush as I can get them. After that, I cut out all of the openings which are supposed to be cut out. If you have an air compressor, blow it off real good. If you don't have a compressor, the computer stores sell canned air which will do a decent job. I then wash everything down with alcohol. This removes any dust left over.

Depending on how the woodwork for the floor is built, I CA all the pieces together to make the floor plate. I then bolt the mechanics to the floor plate and do my trial fitting into the fuselage. Be sure to not only get the correct location for the mainshaft coming out of the top, but also be sure that the mechanics are not leaning left or right. I try to line up the main shaft with the seam in the top back part of the fuse, if it was joined on the center line. When I have my location where this woodwork is going, I take a pencil and lightly mark the four corners where the wood sits. Make light marks because pencils are graphite, and is a good lubricant for epoxy not to stick. At this time I also cut some light weight fiberglass cloth the length of each side, and front and back. Mix up some 1 hour epoxy, and brush the bottom of the fuse across all four edges overlapping the area the wood is going to set at by at least an inch on either side. Set the woodwork, with the mechanics still attached, inside the fuselage, and verify that it is still in the correct location. I then brush epoxy onto the wood area which contacts the side of the fuse and floor, and taking one of the fiberglass strips which you cut, press it into the wet epoxy, overlapping the wood and fuse. Use an acid brush to tap down the cloth until it "disappears" into the epoxy. Do this on all four sides of the former. After that, I brush another light coat of epoxy on top of the glass cloth, and let that dry at least a day. Remember a couple of things; more epoxy is not better, it is worse. The thicker the epoxy is, the more brittle it becomes. Be sure to get all the air bubbles out of the cloth after you push it into the epoxy. An air pocket is going to be a weak spot in the cloth. Be sure to push the cloth down in the edge between the wood and the floor. Using 1 hour epoxy should give you more than enough time to install the base woodwork and cloth, but if you don't feel comfortable using this, use 2 hour or longer epoxy. It will have to dry longer before moving on. I also use 5 min epoxy on any non-structual formers such as one which might hold the fuel tank, or the front cockpit floor former. As long as you cleaned and sanded the fuse well enough before you started, you will have no problem.

Once the base wood work is installed into the fuse, you can move on to the upper reinforcements and the tail drive for the heli. You can fuel proof your woodwork by spreading on epoxy, then take a scrap piece of plastic and use it like a squeegee to smooth it out and take off the excess. When it dries, it will be nice and flat and fuel proof. Be sure to not get any epoxy into the mechanics bolt holes. Leave a junk screw in these locations and work around them.

TAIL DRIVE INSTALLATION After all the base woodwork is installed in the fuselage, you can install the tail rotor drive system. It is very important that you get the drive lined up square with the tail rotor in the back to eliminate any possibility of runout on the drive system. The reason is simple, vibration. Take the former to which your tail rotor assembly attaches to, and be sure it is a tight fit into the end of the tail boom. Dry fit to be sure it fits right. Remove from the fuse, and mix up some 1 hour epoxy. Spread the epoxy in the area in which the former will make contact with the fuselage. Reinstall the former with the gearbox attached. With the tail rotor blades attached, check from the back to see if the gear box is level and the blades are not tilted in toward the fuse when you rotate them on the front or rear of the fuse. I let this dry overnight, then the next day,remove the gearbox, and put a fillet of epoxy around the edge of the former. After all this is dry, I have the mechanic end of the drive system complete.

With the tail rotor out of the former, install the drive system, so that the excess drive sticks out of the back of the tail boom through the former. I install the end on the tube, claw coupler or dogbone, or attach the wire end to the tail rotor itself. Then I measure the distance between the outside face of the former to the inside face of the tail rotor assembly which is going to sit on the former. This is the distance which you are going to shorten your drive tube or wire. After cutting the amount needed, attach your end permanently to the drive, and see how it fits. If you measured correctly, it should be fine. Be sure to use locktite on any connectors which attach to the drive, and some manufacturers even have you epoxy the attaching end on. If you are using wire drive, be sure the wire goes into the tail rotor drive as far as you can when measuring before cutting, otherwise you will get a inaccurate measurement.

Now I install any former with a bearing or a former which holds the brass tube in the case of a wire drive. I leave the former loose in the fuse until I have this distance cut, and the system attached. I then push the former gently to where it should be and spin the drive system so that it finds it own center location. Once this is done, I epoxy the former in this location and let dry. Once dry, I remove the mechanics so that I can put a layer of cloth around the edges of the former for real good support. Doing the drive system in this manner will give you a real smooth running, true drive system which will be trouble free.