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Rail Buttons on a BT-60

  • Todd Lainhart
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1 week 3 days ago #9190 by Todd Lainhart
I'll probably build an Estes Extreme-12 over the winter, which is a 2-stage E12-based rocket. Because of its weight, I'd like to try some rail buttons (which I've never used).

Typically rail buttons are mounted TTW, and so I'm wondering if I'm going to be able to secure a nut deep into the body tube. Anyone have experience here?

An alternative is to use surface-mount guides, as in:

www.apogeerockets.com/Building-Supplies/...niversal-Rail-Guides

-- Todd

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  • Guy Wadsworth
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1 week 3 days ago #9191 by Guy Wadsworth
One technique I have used is to loosely tape the nut to a sufficiently long flat stick of wood, and turn the screw from the outside to secure it. Then a dab of epoxy to to make sure it stays.

Guy
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  • John P. Petrakis
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1 week 3 days ago #9192 by John P. Petrakis
I would think if you drilled a hole in the tube, then in a JT-60C (cut in two for the two rail guides), secured the nut to the inside of the JT-60C, lined up the holes.... Perahps a bit more complext but then you'd have additional tube strength (thought this one up last night). Of course you'd have to place the couplers inside the tube prior to the motor mount etc.
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5 days 1 hour ago #9196 by Frank DeAngelo
As interesting as JP's method is I have done this in the past using Guy's methodology. What I do when possible is to insert a spare tube coupler into the body tube under the area where I am drilling. This gives the BT some support. I usually start with a very small bit and work up the the final size. After drilling I use some CA and let it wick around the hole to give it strength. You can then work the bit by hand to make sure the hole is cleaned out. I use blue thread lock when securing the screw into the flange. I'm sure everyone has their own little touch when performing this task. BTW no rod whip with rails.
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  • Todd Lainhart
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4 days 23 hours ago #9198 by Todd Lainhart
> BTW no rod whip with rails.

Right. I have a feeling that with this particular rocket, I'm going to get rod whip, so I want to give it as much stability support as I can.

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4 days 21 hours ago #9199 by Frank DeAngelo
One time I launched a rocket that has a 3/16 launch lug on a 1/8 rod because I was too lazy to change it out. The rod whip caused the rocket's trajectory to head toward the high brush. Fortunately I was able to find it.

I know that the MARS rocketry club out of Geneso, NY does not allow 1/4" rods depending on the size of the rocket and the engine. Anything mid power I use rail buttons.
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