Apogee Saturn V Launch Lugs or Rail Buttons?

[MALBAR 70]

I'm at the point in my build where it's time to consider how I'm going to get the rocket on the pad. The kit comes with !/4" lugs, but I'd prefer to use buttons. I'm wondering what those of you who have built this rocket decided to use and why? If you used rail buttons, I'd also like to know how you attached them.
Thanks.

 

[Daddyisabar]

I have seen them launched both ways, rod and rail. I guess it comes down to how cool you are.
Do you want to impress the oldschool dudes with their silly launch lugs, 6 foot stainless steel launch rods and endless babble about multiple coats of toxic sanding sealer making their balsa look like glass; or do you want to be young, good looking, cool and hip, ripping your high powered bird off the rail flying the latest electronics. Are you scared to death of quarter inch rods inducing some sort of terminal rod whip on large rockets using more than an F motor, necessitating an all out ban on quarter inch rods? Are you stuck in the 20th Century with rods or have you made the great leap into the 21st Century with vastly superior rail technology? The thin walled Apogee kit is old school and I heard from one builder who started with the lug and later added buttons that adding the buttons was a pain given the need for reinforcement and aesthetic compromises. Maybe he will chime in on how he did it.

She is a big light kit that will act like a sail. Hey look! We have a little wind and the old fart can't launch because of his week rod and underpowered mellow motor designed for some sort of slow, smoky NASA style lift off. Bulletproof with light glass and use one of those awesome sparky motors that are banned out West. Launch off the rail, hear the applause from the crowd, put on your mirrored sunglasses and drive home in your Bugatti with your Trophy girlfriend in the passenger seat.

 

[Event Horizon]

Now that's a fantasy world this guy lives in

 

[dhbarr]

Now that's a fantasy world this guy lives in

Sometimes a piece of it leaks out and falls into the sky.

 

[MALBAR 70]

I have seen them launched both ways, rod and rail. I guess it comes down to how cool you are.
Do you want to impress the oldschool dudes with their silly launch lugs, 6 foot stainless steel launch rods and endless babble about multiple coats of toxic sanding sealer making their balsa look like glass; or do you want to be young, good looking, cool and hip, ripping your high powered bird off the rail flying the latest electronics. Are you scared to death of quarter inch rods inducing some sort of terminal rod whip on large rockets using more than an F motor, necessitating an all out ban on quarter inch rods? Are you stuck in the 20th Century with rods or have you made the great leap into the 21st Century with vastly superior rail technology? The thin walled Apogee kit is old school and I heard from one builder who started with the lug and later added buttons that adding the buttons was a pain given the need for reinforcement and aesthetic compromises. Maybe he will chime in on how he did it.

She is a big light kit that will act like a sail. Hey look! We have a little wind and the old fart can't launch because of his week rod and underpowered mellow motor designed for some sort of slow, smoky NASA style lift off. Bulletproof with light glass and use one of those awesome sparky motors that are banned out West. Launch off the rail, hear the applause from the crowd, put on your mirrored sunglasses and drive home in your Bugatti with your Trophy girlfriend in the passenger seat.

Thanks, after reading that, I've decided to go with a tower.

 

[Daddyisabar]

Apogee sells some cool rail guides that might not look all that bad and they have a large gluing surface.

 

[David Schwantz]

I put a full length internal launch lug in mine. Can't see it, and I like sanding sealer

 

[Daddyisabar]

Old school RULES! Saw some gorgeous finish on Balsa nose cones but no Saturn V's. Maybe next launch.

 

[vcp]

You know, there is another option. Something I've used often with perfect success: Launch Loops. Nothing new, they're mentioned somewhere every few years. I can't say I invented them, but I'd never seen them in use before when I started using them in the '60's. (One of my models at NARAM-11 was handed back to me when the safety check-in guy said I'd forgotten the launch lug... I pointed out the loops.)

Sorry, no photos, I've no extant models that used them. But it's dead simple. A piece of music wire about 2-3" long, maybe 0.040" diameter. Bend it in a 'U' shape with the inside fitting the diameter of your rod. Then bend both legs 90 degrees in the same direction, perpendicular to the 'U', such that the height of the 'U' is your launch rod diameter plus the thickness of your body tube + a fudge. Use a pin to poke two holes in the body tube, spaced the same as the legs of the loop. Poke the legs in the holes up to the bend, then crank it 90 until the 'U' is standing straight out of the body and the legs are flat against the inner wall of the tube. Coat the inside legs with glue and/or lay an epoxy-soaked patch of fiberglass over them. That loop is going nowhere, is unbreakable, and is darn near invisible. You can even install it after painting.

Note that the launch rod will be laying against the body of the model, and if the rod is dirty, it could smudge the model. A small sliver of wood/plastic could be glued within the loop as a stand-off. The bend of the loop height would have to be adjusted to allow this.

I don't think it matters if the legs point forward or aft in the tube. One limitation on installing them is that the inside of the tube must be free of interfering internal structures - motor tubes, centering rings; though in some cases I have installed them first, with the legs held down by a centering ring.

 

[r12ski]

Apogee sells some cool rail guides that might not look all that bad and they have a large gluing surface.

I am in the same boat - trying to find a rail solution while keeping the weight down. So I emailed Apogee.

My email:

“I’m building my Apogee Saturn V and I wanted to know if you had any recommendations for or sell rail guides that will fit the main body tube. I know I can use a traditional rail button with the spacers that you sell but I don’t want the extra weight of weld nuts or t-nuts. Will either the 5.5” conformal guides or universal guides clear the details on the corrugated wraps?”

Apogee’s response:

“Hi Rob,

So we went and pulled the rail guides and gave them a try on the Saturn V we have on display here. To be honest, the answer is they could work but after trying them, we don't recommend either for this application. We kow folks can get really creative with building up or scaling down components to retro-fit them, so we will never tell you anything is impossible, but they are so close, out of the box, that we are pretty concerned they will drag. The 5.5 fit better, but the margin for error is too great to get our official blessing. I hope this is helpful information.

Theresa Mitchell
Customer Service”

So I would recommend either using a rail guide with a spacer or a rail button with a spacer. My solution is going to be to reuse a (PML?) aluminum conformal rail guide for a 5.5” tube that I salvaged from my Minie Magg and add 1/16” balsa as needed. The thin balsa will bend without much effort and I can buildup the thickness to clear the fairing.

I’m a long way off from that step but if it works out I’ll take pictures.

 

[cbrarick]

well nuts and rail buttons...

 

[MikeT]

Interesting. I'm at the point with my Saturn V where I need to decide. I could go either way but I'm concerned about drag using the rail. I'm leaning toward a 1/2 inch rod. I still need to add the decals.

Mike

 

[Greg Young]

Interesting. I'm at the point with my Saturn V where I need to decide. I could go either way but I'm concerned about drag using the rail. I'm leaning toward a 1/2 inch rod. I still need to add the decals.

Mike

I wouldn't worry about drag using rail buttons/guides and launching from a rail vs what a lug on a 1/2 inch rod offers.
I am converting even my older MP and LP kits to mini/micro buttons and rail use. Rails offer more predictable initial flight trajectories.
Besides, between the two, buttons look much neater on a model, compared to a lug.
When it comes to scale models, depending on the model's shape you could use fly away rail guides, eliminating the need to install any lugs/buttons on your model, or use a tower if one is available.
If it was my scale model, I would go with the fly away rail guides or a tower (if one was available).

 

[MALBAR 70]

I ended up using threaded inserts set in a blob of epoxy. I use three piece rail buttons, so I sacrificed one and used the disk parts to act as stand offs under the actual buttons. This should be enough for the rail to clear the wraps.
By using the inserts, I can make a lug/stand off that can be threaded in as well, giving me both options