2nd first stage fin is drying, working on gluing together the 2nd stage fins now.
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I will need to do some epoxy fillets on these fins once this glue dries.
You don't know me very well!You don't need the strength
I will use epoxy for this rocket.
I will look for the silicon sealer though, it is a good tip. Thanks!
Are you using a stiff/hard sanding block of some sort to sand your fins? One technique is draw lines parallel to the leading and trailing edges, sand to the line, re-draw more lines, sand more, etc and this helps a LOT, especially with airfoils on Wings, but works well for rocket fins also. Truthfully, the more curved airfoils you have are more aerodymically clean for the speed of this rocket than the more angular airfoils of the actual (and much higher speed) Black Brant. Cool project!
Finished ALL FOUR!
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And then I realized I had to do the same exact thing with the 4 second stage fins--
Here is the assembly to line up the centering rings before I glue them. (No I am not gluing this all together yet)
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Gee, you are not afraid a power sander would take too much off, since it is balsa?I am using an orbital sander and turning it upside down. Not trying to do anything fancy, so as long as it looks cool it's fine with me. I do need to get a sanding block, though. Thanks for all the !
Some sort of sanding block is really an essential tool. Often you can get away with just putting the sandpaper on the bench but there are plenty of times you need to hold it in your hand. The Estes Ultimate Sanding Bar appears to be a fairly direct copy of the late lamented Great Planes sander, and it's great. But you can get away with cheaper solutions if desired. I wish I had bought at least a couple more Great Planes sanders while they still existed.I do need to get a sanding block, though. Thanks for all the !
You just have to go slow with it.Gee, you are not afraid a power sander would take too much off, since it is balsa?
Yes I know I need to get one I just keep forgetting about it. I will make sure to get one with my next parts order from apogee. The apogee one looks like higher quality and is also bigger. I don't order much Estes anymore. (other than kits)Some sort of sanding block is really an essential tool
I used a belt sander to do mine.. fine grit and light pressure checking very often.. saved my shouldersGee, you are not afraid a power sander would take too much off, since it is balsa?
They were asking me, I can send pics in a private message as I don't want to hijack your build thread.. was just saying I also used a power tool.. I clamped my belt sander upside down in my bench vise so i could use both hands shaping the fins. I need to go look to see what the grit was.. you already showed a pic of your airfoil profileI used 400 grit sandpaper. I am ok with the results, but If I did it again I would get a sanding bar and sand off a straighter line like the real thing. As for a cross section I don't know what you mean- of the whole fin, the airfoil?
Thats what I thought.you already showed a pic of your airfoil profile
I am always ok if anyone posts any pictures of their own build or posts their own comments especially if it is to help another TRF member. Anyone is free to post pictures of their own black brant XII if they want!I can send pics in a private message as I don't want to hijack your build thread
Smart! Didn't think of that. They actually did not take long to sand. The fins, on the other hand....Nice work on those. I was lazy and whipped up designs in CAD for them and printed them. Less time than all the sanding
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