Just starting a trident build. Just sanding and sealing all those nosecones takes awhile. I got a question for all of you. The fins on this model are only 3/32 thick and seem awful flimsy. I am thinking of tracing them out on some thicker stock. What do you guys think?
As @Oldschool77 says, balsa density can vary enormously. The difference between a very hard piece of 3/32" balsa and a soft piece is night and day. It is always possible that you got a soft piece. Or maybe not, and your senses are fooling you.
Here's how to check:
1) Weigh the full set of fins.
2) Measure the dimensions of the fins. Ignore the bit at the rear that curves to match the tail cone.
This will be enough to calculate the density of the balsa in your fins, and it will confirm if you really got a soft set, or if you're worrying about nothing.
If they really are soft, then I would repeat that simply papering them is probably the easiest solution. As @BABAR says, gluing paper onto each sided affords the most strength. Or you could cut a new set from a harder piece of 3/32" balsa.
I papered mine with label paper, then went over that with thin CA. The fins have survived about 10 flights almost completely undamaged, and that method only added a few grams per fin.
Be careful with the thinner tubes, they are easy to tweak when putting together. As for the fins, I used label paper and then CA on the edges and they are as solid as ply.
Thicker stock will add a little weight and drag on an already heavy draggy model. I would avoid A engines then, barely enough altitude to pop a chute. But the thicker fins will survive the landings better.
While sanding the fins I broke a corner off and had to glue back, so it looks like I do need to do something. I traced the fine on to a heavy stock paper just in case but I decided to go the papering route. Notice the left fin.
I was concerned that the lower tube's nosecone was only 3" from the top of the motor. I thought that this might eventually burn the base of the nosecone, so I glued a bit of aluminum foil to the base. Don't know it will help anything, but what the heck.
Instead of tying the shock cord to the lower nosecone of the upper tube. I used some kevlar cord and tied the shock cord to a snap swivel on the other end.