Tripod-based quick change pad

I just finished putting together my new launch pad. It's basically a 3/8" drill chuck mounted on a camera tripod. The chuck itself was taken from an old B&D Firestorm cordless drill that died. I had a coworker machine a few parts for me to put this together, including a thread adapter to go from 1/4-20 to 3/8-24 to allow the attachment. The guts of the adaptation:


The other thing that may unique is that I designed two different sized adapter "cups" to allow mounting of a rail into the chuck. These are aluminum billet, spun down to 3/8" on one end, with a bore in the opposite end to insert the rail into. I made one for 10mm Makerbeam and another for a 20mm 80/20 2020 beam. This shows the rail cup for the 10mm beam:


The main blast plate is from an old Estes Portapad-E that broke, and the smaller plate to protect the chuck is 4" diameter washer that I found in some hardware from my grandfather's old shop. The tripod itself is Dolica Pro Somethingorother. I used it because it has legs that can spread out almost flat, has a ball head, a leveling bubble, and has a hook on the bottom for anchoring. With a keyless drill chuch to clamp the guide, switching between rails and rods is fast.

With 1/8" rod:


3/16":


1/4" rod:


Microbutton rail:


Minibutton rail:


One other nice feature of the ball head is that it can tip down 90 degrees, which makes for easy loading on a long rail:


The rods I am using are 4' long, and made of carbon fiber. The CF is sort of an experiment to see if they'd be stiffer, less prone to whip compared to steel. Jury's still out. The micro button rail is 5' long, and the mini button rail is a 6 footer. So, guide length isn't a problem, at least in terms of velocity leaving the guide. I have to add some loctite in a few places, but otherwise its ready to go. I expect to be able to test it this weekend.

That's pretty cool. To bad someone don't mass produce something like this. I'd buy one.

Thanks. I'd imagine that if the demand exists, someone will. Frankly, the bits and pieces are simple enough - the thread adapter can probably be obtained commercially. If you were to supply your own tripod and chuck, then its just a few bit pieces to adapt the two. If this sort of thing works, maybe somehow one of the vendors would convinced to make an adaptation kit.

The only thing that's somewhat new here are the rail cups, I think. And maybe they aren't even as new as I think, I don't know. In this case, they are barstock turnings, and the bore is sized so that the rail has light press fit. Basically, you can slide it into the cup with some force, but it won't fall out readily on its own. If that doesn't work as well as I'd like, it'll be easy enough to drill the cups for set screws. But if someone wanted to build their own as a DIY project, I could pass on the drawings needed for the parts.

That's a really nice versatile setup!

Woody's Workshop said:

That's pretty cool. To bad someone don't mass produce something like this. I'd buy one.

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Odd'l Rockets makes something similar. Look here for the Adeptor:
https://oddlrockets.blogspot.com/p/accessories.html

Well, its true that their device allows mounting of a rod to a tripod, it only allows 1/8 or 3/16" diameter rods. That's definitely limiting. I tried to devise something that was as flexible as possible. I did not bother trying to use it with a 1010 rail, since the rockets I have that would use that are ones I'd probably only fly at a club launch, and they have larger rails well covered. But, OTOH, this covers everything I might need when launching privately, including rail launching small rockets. More & more I'm not building with traditional lugs anymore, unless the design is peculiar and a rail can't be used. But that's not real common...

I didn't realize the limitations of the Adeptor. It's pretty cool you made something that is capable of handling so many different sizes of rods/rails.

I used the pad on Sunday at the URRG launch. The new pad worked pretty well, I didn't have any major issues with it. I was able to change guides several times without adding too much time. There are a few minor improvements to be made, but all told, this works. I made several flights off of the 20mm rail and the 1/4" rod. I only used the 10mm rail once, though.

The one issue I found was that it appears comments that have been made regarding micro button fit in a 10mm Makerbeam rail are true - it is snug, and can bind if the rocket tips slightly or is under thrust. My Baby Bertha spent most of its thrust trying to climb off the rail, and burned out shortly after leaving the rail. No harm done, but I think either the rail needs to be opened up slightly or the buttons modified. It seems like button modification would be easier, but changing the rail would a one-time job. Hopefully, railbuttons.com updates the design some.

AlfaBrewer said:

I didn't realize the limitations of the Adeptor. It's pretty cool you made something that is capable of handling so many different sizes of rods/rails.

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There's reasons why it has limitations - it's really meant for LPR launching.
Use it with an easily obtained camera tripod, something you probably already have.
Many don't have the tools to make a tripod launcher.

The Adeptor is easily removed after a launch and is again ready for use with a camera.
I wouldn't recommend launching anything above an E engine on a standard camera tripod.

I found myself on the ground trying to connect clips. There had to be a better way.
That and I hated the LPR launchers with the lightning bolt legs.