Best way to mount rail buttons

[REK]

Do those go in standard 1" 80/20?

Of course, they were designed for the standard 80/20. They slide in and out real smoothly too.

 

[degreaser]

This is one way to do it. The mount is a stack of centering rings epoxied together, cut to fit in the well. There are sets of two as I had intended on using PML rail guides rather than buttons but buttons will work just as well.

 

[REK]

They'll stay on as long as the paint does. Let's hope that you have super sticky paint that will never peel off.

The paint is really stuck to the airframe as well. You would expect to be able to rip it off with your hands. Well guess what I tried it and it wont budge.

 

[REK]

Gotta agree with jsargevt. The jb weld and the paint are stuck for good but you've got no bond with the airframe. Best practice is to scape down to the bare body tube before gluing.

In my opinion and experience there is no worry since the rail guides slide in and out real easy from the rail. You both make it seem as though the paint will peel off due to the force of take off. Well guess what Ive launched a 54mm rocket on an I and J motor and the guides never came off and my rocket flew straight up into the air. Let me ask a personal question, have you both even tried them before?

 

[bill2654]

I like the Acme rail guides and I always JB weld them to the airframe BEFORE painting. Your skating on thin ice darklord.

 

[REK]

I like the Acme rail guides and I always JB weld them to the airframe BEFORE painting. Your skating on thin ice darklord.

I must be one lucky dude I suppose. In your experience loading your rockets on to the pad, do they slide in real easy?

 

[bill2654]

Yeah they slide great. I have also forgot to install rail buttons on a painted and finished rocket. I sanded off the paint and JB'd the rail guides on. I hated to do it but it's better than risking an accident.

 

[REK]

Yeah they slide great. I have also forgot to install rail buttons on a painted and finished rocket. I sanded off the paint and JB'd the rail guides on. I hated to do it but it's better than risking an accident.

My point being that they slide in and out with ease is that there is no risk of an accident when bonded over paint. If such accident was possible you would have been able to rip the rail guides off with your hands. I've always found if you can't break it, it will survive.

 

[jadebox]

Oh ... here's a tip regarding rails and rail buttons ....

Purchase a short length of 1010 (or 1515 for larger rockets) extrusion from McMaster-Carr or eBay to use to check your rail buttons. It's better to find out that something's wrong in your workshop than out at the launch pad. A short length of rail doesn't cost much and the shipping cost is low.

-- Roger

 

[REK]

Oh ... here's a tip regarding rails and rail buttons ....

Purchase a short length of 1010 (or 1515 for larger rockets) extrusion from McMaster-Carr or eBay to use to check your rail buttons. It's better to find out that something's wrong in your workshop than out at the launch pad. A short length of rail doesn't cost much and the shipping cost is low.

-- Roger

I dont need to test it since I've already tried it, but you are right to do that first. You can also get the 80/20 rails at Amazon for $3+ shipping and handling.

 

[Ez2cDave]

My point being that they slide in and out with ease is that there is no risk of an accident when bonded over paint. If such accident was possible you would have been able to rip the rail guides off with your hands. I've always found if you can't break it, it will survive.

Hmm . . . 6 years later . . . I wonder ?

Dave F.

 

[David Schwantz]

I also like a ply backer in the airframe. I run a blind nut on the inside, epoxy it in place and then glue the whole assy on the inside. Run a flat head thru the rail button into the blind nut with blue loctite. Make sure it can rotate.

 

[Buckeye]

Hmm . . . 6 years later . . . I wonder ?

Dave F.

More dead threads, Dave?

 

[jahall4]

You want to go to great efforts to attach you rail guides. Something bad happens you don't want to be in a position where you have to say they could have been attached better.

For example:

https://www.facebook.com/TheMarvinW...xZrpRvOUSgGxqtKCzayuRB6bsoOcUsEEidW&__tn__=-R

https://www.facebook.com/TheMarvinW...091625219174/1140033882758281/?type=3&theater

 

[Ez2cDave]

More dead threads, Dave?

Yep . . . Probably more on the way, too . . . Don't like it, don't read it !

Dave F.

 

[David Schwantz]

No such thing as a "dead thread" Lots of good info out there. How many times have you told someone "just do a search", there has already been a thread on that

 

[Ez2cDave]

No such thing as a "dead thread" Lots of good info out there. How many times have you told someone "just do a search", there has already been a thread on that

David,

Spot on, sir !

On online forums, "just do a search" is the equivalent of "go away, kid" or "get off my lawn" . . . Rude & unnecessary . . . It is better to not answer a question at all, than to post some type of "snarky", insulting crap !

If I find someone asking for help, I do my best to try to help them . . . Others, not so much !

Dave F.

 

[artapplewhite]

Here is an idea.


Art Applewhite
https://www.artapplewhite.com/free/popscicle_stick_ rail_guides.html

 

[Andrew_ASC]

I’ve found epoxying standard rail buttons worked for lightweight 29mm MD rockets. I scaled that up to a 54mm non MD 3.34 pound Wildman RB-05A fiberglass rocket. The rail button snapped off on a cert attempt while sliding down rail. The RSO corrected the issue with a drill, screws, and epoxy.

That was my humbling moment with rail buttons. I don’t want to think where that rocket could’ve gone had the buttons failed up the rod. I don’t care how low of a probability it is.

 

[JohnCoker]

Agreed; you need some backing for rail buttons in all airframe types. I prefer small wood squares with a T-nut through the center. (This provides a larger anchoring surface plus arranges so that the barrel of the T-nut doesn't end up proud of the tube surface.)

 

[solid_fuel]

John, I have some weld nut backed 1010 buttons that look like they are supposed to be proud of the tube surface. I forget where I got them but it was a Rocketry vendor. The button fits over the threaded barrel. The barrel sticks up about 3/16 of an inch from the outer tube surface. Do you recommend modifying this?

 

[Titan II]

John, I have some weld nut backed 1010 buttons that look like they are supposed to be proud of the tube surface. I forget where I got them but it was a Rocketry vendor. The button fits over the threaded barrel. The barrel sticks up about 3/16 of an inch from the outer tube surface. Do you recommend modifying this?

Those work well as designed.

 

[solid_fuel]

In a cardboard airframe such as Loc makes do you think I need to add any backing support? I just epoxied them to the inside of the tube.

 

[Titan II]

In a cardboard airframe such as Loc makes do you think I need to add any backing support? I just epoxied them to the inside of the tube.

No. If you have the ones I think you have sold by CSRocketry. BTW...what rocket?

 

[solid_fuel]

I don’t think it was CS Rocketry, but maybe it was. I think I have a few from different sources that are very similar. It’s on a Loc Magnum 3 motor cluster. Here’s a few pictures.

 

[MALBAR 70]

No such thing as a "dead thread" Lots of good info out there. How many times have you told someone "just do a search", there has already been a thread on that

Yes! Thanks Ez2cDave for reviving this thread. I'm currently building an Apogee Saturn V and I was trying to figure out how I was going to attach rail buttons to it. This thread has given me some good ideas.

 

[Titan II]

SF....it will be fine.

 

[krislhull]

On the majority of my builds, I will epoxy a plywood tab to the centering ring, insert it into the airframe, then drill through the airframe and the plywood tab. I then pull everything back out and install a threaded insert into the tab for mounting the rail buttons. I use this method on all of my 3” and larger builds.



In this last photo, you can see both of the tabs on the LH side of the motor mount tube.

 

[Steve Shannon]

On the majority of my builds, I will epoxy a plywood tab to the centering ring, insert it into the airframe, then drill through the airframe and the plywood tab. I then pull everything back out and install a threaded insert into the tab for mounting the rail buttons. I use this method on all of my 3” and larger builds.
View attachment 372098

View attachment 372099
In this last photo, you can see both of the tabs on the LH side of the motor mount tube.

That’s a good way to do it. I’m lazier. For something like that I just drill directly into the centering ring and put the rail button screw through the body tube and into the centering ring with epoxy.

 

[solid_fuel]

On the majority of my builds, I will epoxy a plywood tab to the centering ring, insert it into the airframe, then drill through the airframe and the plywood tab. I then pull everything back out and install a threaded insert into the tab for mounting the rail buttons. I use this method on all of my 3” and larger builds.
View attachment 372098

View attachment 372099
In this last photo, you can see both of the tabs on the LH side of the motor mount tube.

That’s the method I usually use. This rocket didn’t have much room due to the three motor mounts. I used that method for the bottom button but I have to use a very short screw.