Zaphod
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This thread is about my Hornet build.
"Hang on a second," says the collective consciousness of the board, "Did the new guy just say he's doing a build thread on the Estes Hornet? That level 1 thing with the too-big fins?"
Yes, that one. I hadn't intended on doing anything special with it, but then one of the fins popped a root-edge corner when I was cutting it out, and after several minutes of profuse swearing and throwing of objects, I saw the silver lining. I decided to convert the bottom 4mm of the fins into tabs. This would allow me to trim away the broken area, teach me how to cut tubing, and strengthen the rocket considerably. I also went somewhat insane for a second and decided to upgrade to a 24mm motor mount. I put it all into open rocket to make sure it would work, and it will, even with the bigger engines. A C11 sim comes out at 160 yds, D12 at 285, so not as obscene as I initially thought. And I can always get an adapter to run 18mm engines anyway.
I even thought for a while at the beginning (having been inspired by qquake2k's excellent Vagabond build thread) that I would convert it to a zipperless design. Not because it needs it, but just because. That was a silly idea that I abandoned almost immediately, but not quickly enough to avoid coping out a baffle plate and sanding it to fit, only to have it snap in half as I tried to bend over the thread of the eye hook.
But he thing that really convinced me to give up on that design though, was the tube coupler. The kit doesn't come with one, but I have some Estes couplers in my stash, except after finding the only one that fit, and sanding and polishing it intermittently for two days, I managed to take it from "I don't think we need any glue here" all the way to "Zarq, is that ever tight!" I just couldn't see it working and the design wasn't important enough for me to go out and find a coupler that would work, or take the time treating the one I had. I recently picked up the D-Region Tomahawk, and that's tailor made for a zipperless conversion, so I'll wait.
Step one: Trim the fins to make the tabs. In the mod design, I positioned the tabs between the two motor mount spacers. This led to them being offset favoring the leading edge. I made the tabs 30mm long and 4mm deep, which should take them right down to the MM tube. I marked the cut lines carefully using an adjustable square, and went to it with an xacto knife. Once I had the first fin cut, and the cuts sanded flat, I used it as a template to mark the other fins, cut each, and then match sanded them. I was pretty happy with the result.
Next I needed to mark the airframe and cut the fin slots. After using the tube guide to mark the center lines, I needed to know how far up the airframe I would need to start. The instructions say to mount the fins 1/2" from the bottom of the tube, so I measured the notch at the trailing edge of the fin and added the two - 1 3/16? How about we call that 30mm instead? Interesting coincidence that the tabs are also 30mm long. Then I checked the fin width -3mm or 1/8". So I carefully measured 1/16" to either side of the center line, and used my Estes tube marker to draw out the lines. Now I needed two rings to mark the upper and lower tab boundaries - one 30mm from the end, and another 30mm up from the first. I used the strip-of-paper method (make sure you use the factory edge!) and enhanced the visibility by running over the edge with a black marker before wrapping it. In the following picture you can see the guide paper around the airframe, as well as the original fins with the offending corner that prompted all of this nonsense.
And the tube with all the marker lines drawn - ready to go under the knife!
"Hang on a second," says the collective consciousness of the board, "Did the new guy just say he's doing a build thread on the Estes Hornet? That level 1 thing with the too-big fins?"
Yes, that one. I hadn't intended on doing anything special with it, but then one of the fins popped a root-edge corner when I was cutting it out, and after several minutes of profuse swearing and throwing of objects, I saw the silver lining. I decided to convert the bottom 4mm of the fins into tabs. This would allow me to trim away the broken area, teach me how to cut tubing, and strengthen the rocket considerably. I also went somewhat insane for a second and decided to upgrade to a 24mm motor mount. I put it all into open rocket to make sure it would work, and it will, even with the bigger engines. A C11 sim comes out at 160 yds, D12 at 285, so not as obscene as I initially thought. And I can always get an adapter to run 18mm engines anyway.
I even thought for a while at the beginning (having been inspired by qquake2k's excellent Vagabond build thread) that I would convert it to a zipperless design. Not because it needs it, but just because. That was a silly idea that I abandoned almost immediately, but not quickly enough to avoid coping out a baffle plate and sanding it to fit, only to have it snap in half as I tried to bend over the thread of the eye hook.
But he thing that really convinced me to give up on that design though, was the tube coupler. The kit doesn't come with one, but I have some Estes couplers in my stash, except after finding the only one that fit, and sanding and polishing it intermittently for two days, I managed to take it from "I don't think we need any glue here" all the way to "Zarq, is that ever tight!" I just couldn't see it working and the design wasn't important enough for me to go out and find a coupler that would work, or take the time treating the one I had. I recently picked up the D-Region Tomahawk, and that's tailor made for a zipperless conversion, so I'll wait.
Step one: Trim the fins to make the tabs. In the mod design, I positioned the tabs between the two motor mount spacers. This led to them being offset favoring the leading edge. I made the tabs 30mm long and 4mm deep, which should take them right down to the MM tube. I marked the cut lines carefully using an adjustable square, and went to it with an xacto knife. Once I had the first fin cut, and the cuts sanded flat, I used it as a template to mark the other fins, cut each, and then match sanded them. I was pretty happy with the result.
Next I needed to mark the airframe and cut the fin slots. After using the tube guide to mark the center lines, I needed to know how far up the airframe I would need to start. The instructions say to mount the fins 1/2" from the bottom of the tube, so I measured the notch at the trailing edge of the fin and added the two - 1 3/16? How about we call that 30mm instead? Interesting coincidence that the tabs are also 30mm long. Then I checked the fin width -3mm or 1/8". So I carefully measured 1/16" to either side of the center line, and used my Estes tube marker to draw out the lines. Now I needed two rings to mark the upper and lower tab boundaries - one 30mm from the end, and another 30mm up from the first. I used the strip-of-paper method (make sure you use the factory edge!) and enhanced the visibility by running over the edge with a black marker before wrapping it. In the following picture you can see the guide paper around the airframe, as well as the original fins with the offending corner that prompted all of this nonsense.
And the tube with all the marker lines drawn - ready to go under the knife!
