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Do you install rail buttons before or after you paint the rocket? I've seen a few build threads that install them before. Do they mask the rail button to keep the paint off the button?
My current plan is to use well nuts where i can't reach the inside of the tube. T-nuts where i can reach.I've done it both before and after painting. Before is best since it's stronger to have it backed with something like a blind nut or block if wood.
Sonetimes you'll find you have to install after because you forgot to install them before!
After should be fine as long as you're not going beast mode motors. Just drill the hole, add epoxy into the hole all around the inside repeatedly with a toothpick, spread some epoxy on the bolt extending out of the button assembly and install. For really big rockets there's other ways, but if you're asking, you're probably not there yet.
Fyi I've never had a button tear out. YMMV
My current plan is to use well nuts where i can't reach the inside of the tube. T-nuts where i can reach.
A simple trick to make masks for the rail button hole (button assembly removed) is to use a hole puncher on masking tape to get little circular masks to cover the spots for painting.
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Sticky side down and use a toothpick to grab it out.
I used to insert the bolt and tape that, but found that it sometimes made the spray painting a tiny bit more bothersome to spray around and maybe cause drips and then removing the painted tape off the screw was a pain too.Interesting, I usually just insert a screw into the tube as a placeholder for the rail button. After painting, I complete the drill out and insert a well nut when I don't have a CR to attach to.
There's also hurricane nuts... similar to T-nuts, but without the T(eeth).My current plan is to use well nuts where i can't reach the inside of the tube. T-nuts where i can reach.
I believe that is what Apogee includes with their rail buttons. Tim calls them weld nuts.There's also hurricane nuts... similar to T-nuts, but without the T(eeth).
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I sometimes use these epoxied in on my hp stuff. It's also flatter, which means little chance of the chute getting caught on it.
I looked at conformal rail guides, but a lot of people seem to have issues with them popping off the rocket while loading on the rail. I'm still thinking of using them on my Loc Weasel, which is barely bigger than minimum diameter.Here are a couple of pics for my post above....basswood standoff and Acme Rail Guide....
For the Acme rail guide, do you stick that onto a painted surface?Here are a couple of pics for my post above....basswood standoff and Acme Rail Guide....
I looked at conformal rail guides, but a lot of people seem to have issues with them popping off the rocket while loading on the rail. I'm still thinking of using them on my Loc Weasel, which is barely bigger than minimum diameter.
What kind were the rail guides? Were they surface mount?When I first started building I used rail guides. After having them pop off the BT when loading the rocket on the rail I stopped using them. I retrofitted buttons on the ones that had guides.
I haven't had a problem with them popping off. When I go to install them, I rough up the backside with coarse sandpaper plus the AF surface and then clean with 91% IPA. I use epoxy to secure. To line up two of them, I use a straight metal yardstick.I looked at conformal rail guides, but a lot of people seem to have issues with them popping off the rocket while loading on the rail. I'm still thinking of using them on my Loc Weasel, which is barely bigger than minimum diameter.
For a new install, no. I have added those to old, painted rockets, but roughed up the surfaces as I mentioned above to Jeff. I've not had a problem when I've added them to painted rockets either. I have used Aeropoxy to secure for larger rockets.For the Acme rail guide, do you stick that onto a painted surface?
My current plan is to use well nuts where i can't reach the inside of the tube.
Yes, surfaced mounted and they came from Apogee. I was uneducated when I started building. Which is why I cut up so many of my early rockets. Most of them popped off when it was cold.What kind were the rail guides? Were they surface mount?
There's also bolt on rail guides and I have ones made by PML that were installed in my X-15 with about a dozen hp flights and no issues (it is sometimes a bear to get it on the rail though since it has to go on very straight while buttons have more leeway). Ymmv. Also I paint over these.
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I now sometimes will use a button on top and a rail guide on the bottom so there's less chance of pivoting after the first button leaves the rail. I've done this on several rockets (including a 3" Punisher that was punished lol) and last night I was setting up my 7.5 V2 for the same.
Of note is that my set of PML rail guides I got in 2015 had holes drilled crooked. I notified them and they said that no one had ever mentioned it! Lol
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Top doesn't look bad, but...
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Bottom you see the right hole is slightly higher.
So you don't epoxy the well nut into the tube?I use well nuts, going through a baffle wall or a coupler used to strengthen the body tube ahead of the motor mount. The increased wall thickness helps the well nut lock the rail button down. It's a rock-solid setup.
Here's my installation test on some scrap tubing:
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After the hole is cut, I seal it with CA, then paint the rocket. Rail button goes on after painting and clear coats are completed. The rail button can be replaced when it becomes worn, and the well nut can be pulled and inspected.
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