Fin Fillet Technique

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Well-Known Member
Feb 13, 2004
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The following is a summary of my fin fillet techniques:

Just so you'll know,what I usually do is tack my fins on first with CA.I then place a small bead of CA on each side once I'm sure that everythings perfectly straight.I will then use something(usually a launch lug) to mark off a guide mark on both the fin and body tube.I do this front and rear.The next step is to use blue painters tape to mask off the fillet.Epoxy is then poured and allowed to sit.I usually mix a small amout extra just to constantly stir and keep an eye on.When it gets to the point where it JUST starts to show signs of "gumminess" I then carefully remove the tape.Any slight drips which occur in the next few minutes are easily smoothed with my finger.Yes,this does leave me with bevel shaped fillets.However,they do look really nice and are plenty strong.As I have said before in Oldrockets group this is my style and I will probably never change it.Now I admit that they are a little weighty but not too much.However,on a shorty like these Goonies I wanna keep as much extra weight off the rear as possible.
Here in a few days I'm gonna be putting up some pics on my Fotki album.I'll tape up one of the fillets and show y'all what it looks like before and after.Finally remembered to get batteries for my digi cam today.
It sounds like your style is like mine. With the body tube laying on its side and CA tacked fin in place, angled at 45 degrees, I place a small piece a masking tape at each end of the fin and the body tube to form a dam. I mix up a batch of epoxy in a 5 oz. dixie cup that I have cut the upper half off of. I then pinch the cup edge to form a spout then pour it into the valley where the fin meets the body tube. Let set over night, remove the small pieces of tape, shape and smooth the fillet end edges with sandpaper and fingernail emory board as needed. I too like the bevel appearance and it seems to me that it also makes for an extra strong joint. It does add a little extra weight but I feel confident that I'm not going to lose a fin (knock on wood).