Ok looked inside last night....The fuse sides are balsa but they have a 1/32" ply doubler on the inside where the wing attached.

So you just glue the plywood rings directly to the sides of the fuse. A couple spots of medium CA the Purple Bob Smith stuff. The tack glue the fiberglass socket the plywood rings same way. Don't get carried away with the CA. We want the epoxy to penetrate and absorb into the ply for the best possible bond.

Then remove the wings and tube after all alignment is perfect and everything is tacked in place....and epoxy the socket and plywood rings in place.

Here is a drawing of the plywood rings and the socket. In this case the socket was phenolic or Carbon. The fiberglass socket is usually lighter weight....but same idea. Sometimes the 1" ID is too large for the socket...so you need to under size this middle hole and open it up with a dremel tool drum sander and the like to get a perfect fit on the fiberglass socket.

Also try to have the socket over sized just enough to pass through the fuse sides too. This will make everything stronger...The socket should come out flush or near flush with the outside of the fuse side. Carefully trimming and trial fitting will get it correct.

This way the socket has a mechanical link to the fuse side not just relying on the glue joint of the plywood rings to the fuse side.

If you have to open up the holes in the fuse side to get perfect alignment only open one side up...this will make life easier. The other side will stay semi tight and the "loose" fuse side will allow for the adjustment. This is a trick to helping in the process.

When triangulation measurements are taken choose a point on the wing panels that is the same...You may have to double check to make sure things are the same. Never trust sanded wing tip edges. However joints where the wing tip meets the foam core are usually pretty accurate. I suggest checking multiple points like aileron cut out corners and such...But measure and make sure they are the same on both wings...Sometimes an error in cutting out the ailerons or facing ti will translate into a problem with the alignment.

Finding a reference you can trust is sometimes difficult. for this triangulation.

Also the reference of the fuse being straight in the roll axis can be a little tough at times too.

You have to find out what you can trust...Don't blindly assume that the canopy rails are the reference, although they should be. On the Focus the bottom of the fuse is suppose to be flat too...but again don't blindly trust it. Setup the fuse on a flat table and check the fuse side with a square. To help hold everything from moving a little trick is sand bags. I have also used bags of pinto beans or little weights. These help keep the fuse from moving around. If you find a reference or can shim the fuse a little here or there and then the canopy rails become the reference and are good use them... Bubble levels, digital levels are great ways to keep checking your reference during the process. Before you glue it all up double check it. Go have a soda or a beer and come back and triple check it. Then glue it in place.

Notice I said 1 beer not a 6 pack...the 6 pack can change the perspective a little.

Its not too hard but is a intimidating task the first time through. I have done it enough...Its a no brainer. You just need some patience.


Troy Newman