Inexpensive mid-power launch pads...

[James Duffy]

Our club will be one of the hosts for the distributed TARC finals this weekend, and we needed some additional mid power pads to support the teams who will be coming to fly. As a bit of background, we have plenty of big, heavy HP pads that can accept rails, but only a single QuadPad (remember those?) for mid-power flights that need a rail. The QuadPad is a perfectly adequate launch pad, but its it heavy, unwieldy, and threatens to remove a digit every time it is moved. The planets for change had aligned.

I've used Ultimate-style speaker and light stands in bands since the '80s, and often mused that they might make an interesting launch pad. The TARC need finally spurred me to gather the hardware and come up with a solution. Inexpensive speaker stands were sourced from Amazon:

https://www.amazon.com/gp/product/B07SCCB1H5
After removing the upper section, holes were drilled through the upright to accommodate a 1/4"-20 T-nut, a 1/2"-long nylon spacer, a pair of washers, and a knob. One need not be a rocket scientist to figure this out.

The T-nut slips into the rail, and the whole assembly is tightened. Note that there are upper and lower attachment points. It was necessary to grind away a bit of the thickness on the T-nut. A small 8020 T-nut was attached on the rocket side of the rail to serve as a support for the rocket.

Here's what everything looks like with rails in place, and with rockets mounted.


The requirement for a blast deflector will be satisfied by simply placing a square of plywood beneath the pad. Total expenditure for three pads with rails and hardware was ~$200. The stand will ultimately get roasted by use over the years, but a replacement unit is less than $40.

James

 

[tab28682]

Nicely done!

 

[Curtis Enlow]

Nice, simple design! I do believe I will use your example in building mine, I just need to find a simple way to include a rod for LPR models.
In hindsight, James, is there anything you might do differently?

A friend used a 90-degree downspout elbow as a blast deflector mounted just below his rail stop and it seemed to work great.

 

[James Duffy]

Nice, simple design! I do believe I will use your example in building mine, I just need to find a simple way to include a rod for LPR models.
In hindsight, James, is there anything you might do differently?

Thanks for the kind words, they have worked well during the busy TARC season.

A friend used a 90-degree downspout elbow as a blast deflector mounted just below his rail stop and it seemed to work great.

We landed on simply laying out a fiberglass welding blanket as a blast deflector solution, then setting the pad assembly on top of that. A packet of two 4' x 6' blankets was about $25, if I recall correctly. Works great!

 

[cwbullet]

I did something similar with 3D printed parts.

https://www.printables.com/model/238122-remix-speaker-stand-launch-pad

 

[BEC]

Another blast deflector alternative made from a dollar store dough cutter, a couple of rail buttons, a two-inch 6-32 bolt and a couple more 6-32 nuts:

Just slide it down the rail. As in:

 

[mikeyd]

I did similar with $20 LED light stands from Harbor Freight, even added an option for rods. I like the speaker stands as they look to have a larger footprint, even though the LED stand has shown to be very stable, and we have had no issue with it.

 

[Curtis Enlow]

I did similar with $20 LED light stands from Harbor Freight, even added an option for rods. I like the speaker stands as they look to have a larger footprint, even though the LED stand has shown to be very stable, and we have had no issue with it.

Love the Trident! My favorite Esdtes rocket as a kid! Is that a kit or did you scratch build it? My ultimate goal is an upscale HP Trident...such a graceful rocket...

Nice to see that carriage bolts fit the channel (I assume that is 1010?). I also really like your blast deflector, can you give some detail/sources on how you made that? I love the adaptation of the drill chuck! A great one-size-fits-all solution : )

 

[Curtis Enlow]

Another blast deflector alternative made from a dollar store dough cutter, a couple of rail buttons, a two-inch 6-32 bolt and a couple more 6-32 nuts:View attachment 574508

Just slide it down the rail. As in:

Dollar Tree is a goldmine of low-cost solutions for all kinds of things! There is a pack of various grit Emery boards (for manicures, etc.) that are handy for sanding and finishing small parts. They have low-cost vinyl for those with Cricuts. You can build R/C planes with their foamboard (plans at Flitetest.com). I have one a block and a half from where I live and use it all the time, for woodworking, too.

 

[lakeroadster]

Inexpensive, I guess is a relative term. The cost of the aluminum 8020 T-slot rail is what has kept me using a 5/16" dia. galvanized steel launch rod... which has been more than adequate thus far for my mid-power rockets.

Maybe someday I'll lay down the greenbacks for one.. till then my launch horse has been there, and worked great. All made from salvaged stuff: sawhorse brackets, 2 x 10, old satellite dish mount and a 5 gallon donut glaze bucket. Only thing I actually bought for the project was the 5/16" galvanized rod.

​

 

[mikeyd]

Love the Trident! My favorite Esdtes rocket as a kid! Is that a kit or did you scratch build it? My ultimate goal is an upscale HP Trident...such a graceful rocket...

Nice to see that carriage bolts fit the channel (I assume that is 1010?). I also really like your blast deflector, can you give some detail/sources on how you made that? I love the adaptation of the drill chuck! A great one-size-fits-all solution : )

The Trident build can be found here https://www.oldrocketforum.com/showthread.php?t=17675&highlight=trident it is a US Rockets "builders kit", from Jerry Irvine, which you can find him on Facebook, but he announced in May he was going to be closing down shop.
The carriage bolts are normal 1/4in diameter
the blast deflector is made in 2 parts held on with a carriage bolt and 1/4 threaded rod "coupler" to act as a stop.
the first part is just a 90 degree flat plate, that I attached to "retrofit post base" then drilled a center hole on the plate to attach to the rail with the carriage bolt, and cut off the overhang on the ends of the flat plate.

 

[mikeyd]

Love the Trident! My favorite Esdtes rocket as a kid! Is that a kit or did you scratch build it? My ultimate goal is an upscale HP Trident...such a graceful rocket...

Nice to see that carriage bolts fit the channel (I assume that is 1010?). I also really like your blast deflector, can you give some detail/sources on how you made that? I love the adaptation of the drill chuck! A great one-size-fits-all solution : )

Here is the Trident on that pad

 

[Curtis Enlow]

the blast deflector is made in 2 parts held on with a carriage bolt and 1/4 threaded rod "coupler" to act as a stop.

the first part is just a 90 degree flat plate, that I attached to "retrofit post base" then drilled a center hole on the plate to attach to the rail with the carriage bolt, and cut off the overhang on the ends of the flat plate.

Thanks for the detail shots - I'm a visual learner and that's perfect!