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RTV Launch Pad
Obviously, the essential piece of ground equipment is the Launch pad. We have
been astounded by ingenuity that many rocketeers have displayed in creating
platforms to get their creations off the ground. Rick and Brad have each built
a pad of a similar design. Were pleased with their performance and so we'll the
plans with you (being that we are so generous and all).
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RTV PAD History
Design
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The Rick Rack in the backyard
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Cool things we've seen used as blast deflectors
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Flower Pots
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Pie Plates
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Satellite TV Dish
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Composite Skill Saw Blades
Bad Things to use as Blast Deflectors
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Cardboard
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Styrofoam
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Bricks of Firecrackers
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Asphalt Shingles
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Diana Ross Vinyl LPs (tempting, but a bad idea)
What we'd like to see as Blast Deflectors (but
probably won't)
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Janet Reno for Governor Campaign Signs
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bin Laden's Turban
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A Grand Slam Breakfast from Denny's
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My old boss's Toupee'
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If you have been around rocketry of late,
you will have seen many launch pads built from PVC pipe. For good reason too.
PVC piping is essentially tinker toys for grown ups. You could build just about
anything from them (though Rick's wife balked at the four poster bed, so there
are limits). PVC piping can be used for just about any thing, just don't stoke
your campfire with it, as the fumes are highly toxic.
The Rick Rack and the Brad Pad are essentially the same, but the Brad Pad has a
few additions. The Brad Pad has a keyless drill chuck to hold launch rods, and
also has a fixture to hold a launch rail. The Rick Rack has now launch rail,
and uses the chuck from a hand auger to hold launch rods. The Brad Pad has
adjustable legs - the Rick Rack doesn't.
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Design: The design
section discusses the construction of the key parts of the pad:
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Top view of the Brad Pad. Both a launch rail and a
launch rod are installed
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Description:
Adjusting the legs of the Brad Pad.
This version of the pad had the plywood disc platform.
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The Basic RTV Design came out of Brad's noggin. He had out-grown
his NCR PVC Launch pad and needed something bigger. Brad wanted to have a
larger platform than the usual PVC launch pad, and none of us liked using
launch pads with wobbly blast deflectors that are just hooped over the rod. We
wanted some thing with a wide solid base that would allow the rocket to
sit on its tailfins, if so designed. So Brad opted to space out the legs and
put a 24" diameter round plywood platform on top (precut at Home
Depot). |
Blast Deflector
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Brad's original blast deflector wasn't
pretty, but it worked -- an old tin plate that rested on the plywood platform.
It had a hole in the center for the launch rod to pass through, and a keyless
drill chuck mounted underneath to hold the rod steady.
About this time Rick was rummaging about in the scrap metal
dumpster at his old employer. There he found a great number of 20"
diameter discs of 10 gauge stainless steel. With the permission of the plant
foreman, Rick carried home an ample supply of
stainless steel blast deflectors. So Brad replaced his plywood disc
with stainless steel, and Rick built his pad after that. There are some slight
variations in the rod mounting and the legs, but those are covered below.
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The Brad Pad Deflecting the Blast of a J350. in the
Jumbo Sizzler |
| The Legs |
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| The design of the legs is simple, Merely a four legged
spider and constructed from easily obtainable 1.5" PVC Plumbing
components. For best results, cut your PVC pipe using a Chop Saw for clean
square edges, and use the recomended adhesives. For a cleaner look, you can
paint your pad as well. There are adjustable legs on the Brad Pad.
Brad launches in the Arizona desert, which has uneven terrain. Rick's club
launches on a perfectly level sod farm in Minnesota, so he has no need for
leveling legs. The Brad Pad can also be angled upwind, but none of us like to
launch in a stiff breeze, so this is a little used feature.
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Underneath the Brad Pad. The metal piece is the attachment for the
drill chuck.
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| Rod Mount |
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| There are lots of options for rod mounts. We think the best choices are
variations of hand operated chucks (or collets).To learn more about Rod Mounts,
click here. |
The chuck mount on the Brad Pad
Bit Brace On underside of the Rick Rack
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Brad Pad Rail Attachment
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