Micro and Mini Rail Buttons

[terryg]

What is the maximum size/weight of rockets that are practical for each of these smaller rail button types?

Thanks for any input or personal experience!

 

[rharshberger]

Micro buttons on 13 and 18mm powered models, Mini buttons on 24mm powered models, 1010 buttons for most others up to pretty large. This is how I do it, not everyone will agree. I fly lots of LPR stuff off my Micro and Mini rails, some small and moderate sized MPR rockets off the Mini rail. The micro and mini buttons are actually stronger than people think, but I match the button to the physical size of the rocket and what will look good to me.
The Micro buttons I usually mount by drilling a hole in the Estes tubing and hardening it with CA, then screwing the button into the hole, just make sure it isn't going to snag the laundry. The Mini buttons I can do that way on smaller rockets, but usually attempt to hit a centering ring and simply drill a hole in it then CA the hole to harden it and either tap the hole or just use the screw for the button to cut threads.

 

[cwbullet]

I have flown minis on midpower but I would not go past F. To be honest, an F16 is not a problem, but I would not use them with a rocket with an F120 or F240 motor.

 

[Kartman]

I flew my 2.6” Madcow Hawk on a H182R today using a Mini-rail. Perfect flight and no signs of distress on the mini-buttons.

 

[cwbullet]

That does not surprise me. Then again, red is not VMAX. It may survive it, but I am not doing it.

 

[Cody Webster]

Dont want to thread jack but perhaps I can find some help and answers to a few questions. I bought micro rail buttons from jonrocket, and I just can figure out what size rail to buy and use these with. I was thinking about ordering several small pieces and figuring it out that way but if I can save the time and money that would be great. Do the micro buttons fit 10mm X 10mm rails? Can someone link the exact rails these work with. All the descriptions I read or recieve are vague and I just wanna get some rails these micro buttons will work with.

 

[Cody Webster]

Another question what length do I need to launch lpr on these micro buttons. Was thinking either a 4 or 6 foot length?

 

[kuririn]

Makerbeam is the 10mm x 10mm rail. Makerbeam XL and Openbeam are 15mm x 15mm. For most LPR 4 ft rail is enough. Might be difficult finding a vendor, I bought my Makerbeam from Jonrocket but they no longer carry it.

I've heard of one more beam called the Nanobeam, it's even smaller.

Edit: Apparently micro rail buttons fit 10mm x 10mm, and mini buttons fit 20mm x 20mm, as described here:https://jonrocket.com/store/category/model-rocket-parts/launch-lugs-and-rail-buttons

So what would a 15mm x 15mm button be called?

 

[Cody Webster]

Amazon haz it, never used the micro rail and it seams that 80/20 doesnt make a rail that small. So far makerbeam and a robot building sight I found appear to carry the correct size.

 

[Cody Webster]

https://www.amazon.com/dp/B01LZNCCBB/?tag=skimlinks_replacement-20 Is what I want?

 

[terryg]

I was not aware of Makerbeam XL. There seems to be a good selection of it at amazon. I think there would be real issues of bending with very long lengths of the thinnest beams. One of our club member uses a a 1010 rail for support and which the smaller rail interlocks with rather neatly.

 

[Cody Webster]

Thanks, think Im gonna order that maker 10mmX10mmX1500 from amazon for my micros.

 

[Kartman]

That does not surprise me. Then again, red is not VMAX. It may survive it, but I am not doing it.

Yes, as with many things “the Devil is in the details”. I think how the buttons are attached is most important. Is it Estes BT80 or LOC thick wall paper? Backed by a nut and washer or just a machine screw and Loctite? Etc,etc,

Tom

 

[Steve Shannon]

Another question what length do I need to launch lpr on these micro buttons. Was thinking either a 4 or 6 foot length?

That depends on the acceleration as the rocket lifts off. If it’s going somewhere around 40-45 feet per second when it leaves the rail the length is sufficient for that rocket and motor combination.

 

[rharshberger]

That depends on the acceleration as the rocket lifts off. If it’s going somewhere around 40-45 feet per second when it leaves the rail the length is sufficient for that rocket and motor combination.

+1 to what Steve stated, however with most stock built Estes/Quest/Semroc/etc LPR kits using recommended motors a 3' rod (old school rod) has usually been sufficient (for a very long time), I bought the 5' Micro rail just because I fly some heavy scratch built models and wanted the extra length. The 5' micro rail is stiffer than the 3/16" rods those rockets used to be flown off. This thread reminds me I need to order another 100 sets each of the micro and mini buttons.

 

[amiliv]

IMO, the choice between using 1010 button and Mini button is what the local club you plan to fly with has on mid-power pods. I simply put 1010 on my mid-power rockets, because none of clubs that I'd call "local" to me has any Mini rails.

Said that, the difference between standard 1010 and Mini isn't that much anyhow. 1010 converted to metric is almost the same as 25x25 (mm), while Mini is 20x20 (mm). If the rocket will fit on the rail, I'd just use 1010 buttons. I've 1.6" LOC Hawk (4 fins on a BT-60 tube) and a small scratch built 1.3" Black Brant III (3 fins on a BT-55 tube). One has 1010 rail buttons, the other has 1010 rail guides. Both fit perfectly on a 1010 rail.

Generally, most rockets that are too small to put 1010 button on them, are already small enough to put Micro buttons on them. This leaves Mini buttons a niche market for those very few rockets that have too small airframes to put 1010 on them, but have too large motors for Micros; i.e. probably only 24mm minimum diameter rockets. If most rockets have 1010 and Micro buttons on them, it makes launch go more smoothly, as there's lees need to swap out rails. Just my $0.02.

 

[terryg]

Here is a side by side comparison of the different rail button types.

 

[terryg]

I have built both Mini and Micro Launch Pads.

 

[terryg]

The Mini-Rail mounts just like a 1010 rail. The MakerBeam XL (micro-rail) is harder to mount.
I found that the makerbeam XL T-nuts work well for mounting and have a side use of being a backer nut for the minibuttons (you have to use metric screws).

 

[hball55]

The Mini-Rail mounts just like a 1010 rail. The MakerBeam XL (micro-rail) is harder to mount.
I found that the makerbeam XL T-nuts work well for mounting and have a side use of being a backer nut for the minibuttons (you have to use metric screws).

A blind nut would be both lighter and less bulky than the solution you have come up with. There’s virtually no chance of laundry hanging up on a blind nut.

 

[terryg]

The blind t nuts that I have stick up much further than the one I have used.

 

[rharshberger]

I dont bother with backing nuts, just drill a small hole in airframe, harden with CA and screw the micro rail button into the hole. On most rockets BT60 and smaller the rocket weighs very little and the button receive very little stress, so far it has worked for me for the last 2-3 years.

 

[amiliv]

I think there would be real issues of bending with very long lengths of the thinnest beams.

Very late with this reply. The micro-rail (e.g. 10x10 Makerbeam) is plenty rigid in lengths that would be used for low power, and way more rigid than 1/8" rods it's meant to replace. The off the shelf length of Makerbeam is 900mm (just shy of 3 feet). In that length, it is plenty rigid and not bending. Micro-rail is really a replacement for 1/8" rods, and it's few inches longer than my Estes 1/8" rod (Estes rod is 31.5", Makerbeam is 35.4").