Repairing a carden yak

[Toby Slihavy]

Everyone hope everyone is doing well!!!! Well I got this project from my good friend Joe Layne. Unfortunately, Joe had a fuel tank rupture and gas went all over the belly pan. The whole entire bottom was eaten up. Joe had used some spray foam to make it through a contest. He did a great job considering how bad the bottom was eaten up. I started by removing the entire bottom then took a bunch of measurements to start drawing the parts in cad. People think yaks are mostly just a circular object. It is far from it, trust me. After I draw the parts in cad, I cut pieces from foam scraps on my CNC foam cutter. I do this to make sure the parts will fit AFTER you laminate 1/16” balsa on it. This way I don’t waste foam as it is expensive.

[Rich Whitlow]

Toby, nice project! Had to do this with my first Carden after a fuel incident. But luckily Dennis was able to send me the belly foam precut! That saved me!

[Toby Slihavy]

Alright one thing I’ve learned building yaks or any curved wood object is to use lots of 1” blue painters tape and a solution of 50/50 isopropyl alcohol and water in a spray bottle. I vacuum bag all foam parts and use west systems epoxy (105 resin/206 slow hardener). When you edge glue all of your 1/16 use titebond 2. I’ll use little bits of tape to pull sheets together then use the tape at a 45 degree angle to its length the more tape you use the less likely a part will crack when you set it into the foam shuck. Once all of my sheeting is dried I’ll apply My 50/50 mixture by spraying the inside of my sheeting (the side that gets the epoxy). I’ll place the balsa over the shuck then place the foam part inside of it. At this point don’t force the wood to bend. Generally if you moistened the sheeting well it will form itself. Here are a few pictures I took of an extra I built (I forgot to take pics of me forming joes yak54), but the concept is the same.

[Toby Slihavy]

Well here are the foam parts made on my cnc. After laminating with carbon fiber and 1/16” balsa the parts are ready to be fitted to the fuse. I use white gorilla glue to attach the bottom turtledeck. I attach one side. Let it dry for 30 minutes, flip the plane over and glue that side. Makes fitting round parts to a flat plane side so much easier.