V2 Plastic to Balsa Glue Question

[Dseter]

Hi folks, working on the Estes V2 with the balsa through the wall fins. The four fins go through a plastic tail cone before getting glued to the motor mount tube. Wondering what you guys would suggest to use for the fillets where the balsa fins meet the plastic tail cone of the V2? These fillets will be mostly cosmetic but will have some stress on with this bird flying on an E9 at most. It would need to bond to both plastic and balsa and be sandable/paintable if possible. Thanks in advance! Dave

 

[rharshberger]

You might try the Loctite Plastic Bonder Epoxy available at most hardware/Home Repo stores.

 

[Kruegon]

I've had decent luck with Testor plastic cement. It bonds well to balsa if it's directly on the grain. Make sure the plastic is clean and oil/debris free. It also helps to lightly rough up the plastic.

Testor cement works chemically. It actually "melts" the plastic slightly so the plastic and cement mix and bond both chemically and physically. Roughing the edge facilitates this.

 

[aerostadt]

I have two of the same model, so I will be interested in what people recommend. I have been so busy with the holidays, etc., I don't know when I will get to these models. My first thought would be to use epoxy (5 min. or 30 min.), because that way fillets can be made with a gloved finger. If I went this route, it would be wise to rough up the plastic slightly with sand paper. Tab built this model for his rocket glider. I wonder what he used.

 

[RocketryBill]

Definitely use two-part epoxy for that. It bonds well to plastic and wood.

 

[Dseter]

Moving along on this build now, ready for the first fillet of balsa to plastic. I have both 30 minute epoxy and some thick CA. I was originally thinking I would need a fairly thick fillet there at the joint between the plastic cone and the balsa but I'm able to make a fairly thick fillet inside the where the fin meets the motor mount. I also sanded the motor mount where each fin will be so as to get through the thin outer layer of wax on the tube. Also, I took a tremendous amount of time to add thin layer(s) of balsa strips to the bottom of the fins to fill in gaps where the fin meets the plastic tail cone. I sanded and shaped those as best I could so now each fin has almost no gap at the tail cone. I will likely use the two part epoxy with some balsa particles mixed in where the fins meet the plastic tail cone and then sand that generously to avoid yellowing in the future. Will post all my build steps in a future thread, thanks for the input so far, anymore is surely welcome! Dave