ThirstyBarbarian
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I'm thinking about building the Mega Der Red Max that I got super cheap at the Fry's sale. I like the fact that it is a big 4" airframe. And everyone has reported it is a nice stable flyer. The draggy design would work well on my club's LPR/MPR field where we can fly up to G motors, but the ceiling is 1,000 feet. I love the fact it only cost $25.
The thing is, I don't really like the style of the rocket very much. I'm not a huge fan of the livery, which of course I can always change. But the shape of the fins doesn't really appeal to me either. I thought about just using the existing material and recutting the fins, but the fins have an interior skeleton of plywood that you laminate balsa to, and I think there are limited ways to cut though it without screwing up the structural integrity of the fin.
So this is my idea --- I do like old retro style Sci-Fi rockets, and I'm thinking if I just slice a bit off the outside edge of the fin, I can leave the outer edge of plywood strong and intact, and I might be able to fit a pod of some kind to the outer edge of the fin for a retro look.
Here are some mock-ups:
Below, the near fin is a cardboard cutout of the existing fin shape with a pod made from NC-60 nosecones and a TP roll to give an idea of the shape I have in mind. The top fin is the skeleton of the stock MDRM fin that I do not really like very much. What I don't like about the stock shape is the angle of the outer edge of the fin. By adding the pod, the outer edge can be parallel to the body tube.
In order to mount the pod, you would need to cut a small triangle off of the corner of the fin. Then I figure you would put a slot in the pod, slip it over the ply and glue the fin edge to the inside of the pod tube, as well as fillets where the ply goes through the slot.
Here I have laid the triangle that I think would need to be cut off the fin edge over the ply skeleton to show how much of the ply would be cut away and how much would remain.
Here's one with the pod mounted pointy end up.
Here is one with a slightly shorter pod.
Here is a pod made of pointy BT-50 cones. The skinnier the pod and the shorter the pod, the more you would need to trim off the outer edge of the fin. Also the fins are going to be thick after laminating the balsa, so there may be a limit to how skinny the pods should be. I believe there are BT-55 and BT-56 cones that are between the two sizes I've shown.
Any comments?
Is this something that is practical to do? Would something like this introduce stability issues or other problems with the flyability of the rocket? Would this put stress on the fins that they would have trouble handling? If I did use plastic nose cones, would that be too fragile for a rocket this size to land on? Should I use something else? Are there any construction tips or tricks for something like this?
How about the aesthetics of the thing? Good idea or bad? Pointy side up or pointy side down? Point on both ends? Short or long? Skinny or fat? None of the above?
I'm interested in hearing what people think. It will be awhile before I can start the build in whatever form it takes. But I'd like to gather some info well before getting started.
The thing is, I don't really like the style of the rocket very much. I'm not a huge fan of the livery, which of course I can always change. But the shape of the fins doesn't really appeal to me either. I thought about just using the existing material and recutting the fins, but the fins have an interior skeleton of plywood that you laminate balsa to, and I think there are limited ways to cut though it without screwing up the structural integrity of the fin.
So this is my idea --- I do like old retro style Sci-Fi rockets, and I'm thinking if I just slice a bit off the outside edge of the fin, I can leave the outer edge of plywood strong and intact, and I might be able to fit a pod of some kind to the outer edge of the fin for a retro look.
Here are some mock-ups:
Below, the near fin is a cardboard cutout of the existing fin shape with a pod made from NC-60 nosecones and a TP roll to give an idea of the shape I have in mind. The top fin is the skeleton of the stock MDRM fin that I do not really like very much. What I don't like about the stock shape is the angle of the outer edge of the fin. By adding the pod, the outer edge can be parallel to the body tube.
In order to mount the pod, you would need to cut a small triangle off of the corner of the fin. Then I figure you would put a slot in the pod, slip it over the ply and glue the fin edge to the inside of the pod tube, as well as fillets where the ply goes through the slot.
Here I have laid the triangle that I think would need to be cut off the fin edge over the ply skeleton to show how much of the ply would be cut away and how much would remain.
Here's one with the pod mounted pointy end up.
Here is one with a slightly shorter pod.
Here is a pod made of pointy BT-50 cones. The skinnier the pod and the shorter the pod, the more you would need to trim off the outer edge of the fin. Also the fins are going to be thick after laminating the balsa, so there may be a limit to how skinny the pods should be. I believe there are BT-55 and BT-56 cones that are between the two sizes I've shown.
Any comments?
Is this something that is practical to do? Would something like this introduce stability issues or other problems with the flyability of the rocket? Would this put stress on the fins that they would have trouble handling? If I did use plastic nose cones, would that be too fragile for a rocket this size to land on? Should I use something else? Are there any construction tips or tricks for something like this?
How about the aesthetics of the thing? Good idea or bad? Pointy side up or pointy side down? Point on both ends? Short or long? Skinny or fat? None of the above?
I'm interested in hearing what people think. It will be awhile before I can start the build in whatever form it takes. But I'd like to gather some info well before getting started.
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