New/Old Personal Launch Pad

[DRAGON64]

We tend to take launch pads for granted because when we were new members, we find that most clubs supply all of the ground support required for any given launch. A concienient benefit of membership. Besides, ground support is one less item we have to keep up with at launches...Am I right?

I have always enjoyed making my own launch pads, nearly as much as I love building rockets; and I have built a number of different designs over the years. The material of choice has always been PVC, but I have also tried steel, and my latest pad, which is constructed of all light weight aluminum.

This week I drug out an old pad I never fully got to enjoy. It was the pad I constructed from 2" square tube steel. A very sturdy and stable design, it suffered horribly from a couple of drawbacks, namely weight and corrosion. Steel is heavy and corrodes pretty badly from the deposits of our rocket exhaust. Who wants to haul a heavy chunk of rust to a launch and out to the field?

Nevertheless, I ordered all 2" square tube aluminum and started replacing all of the ugly parts of my High Power Rail Pad. I am nearly finished, all that is left is the mast that will hold the rail. The legs are 36" long, and the mast will be 48" long.

Pic 1 - New steel pad with an old PML Endevor mounted to it...

Pic 2 - The pad as it looked when I took out of storage...rusted and ugly

Pic 3 - The begining of the clean-up of keepable parts, and disgarding the heavy rusted parts

Pic 4 - The new aluminum components installed (except for the rail mast)

Pic 5 - Legs deployed in a 3-point 120 degree radius. Very stable with it's low center of gravity.

 

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IMHO, there are pros and cons to each type of material.

While steel is heavier, you need to use 3X's the thickness with aluminum to get the same strength and resistance to flexing. Since aluminum weighs 1/3 that of steel, you'd end up with materials weighing the same to get the same strength. Steel is easier to weld, and if you paint it with a decent paint, it will hold up pretty well. Aluminum will also corrode from the exhaust (look at your launch rails), and unless you use a material like never-seize, the steel bolts will have a galvanic reaction with the aluminum and corrode at the joints.

Pricewise, assuming you use the thicker aluminum to equal the strength of steel, it'll cost more. For a one off build, that's unimportant, but with a club that purchases multiple pads, that could become a factor.

These are just a few of my observations. Your Coker style pad is a nice piece, and with the 2" square legs, aluminum was probably the best choice as 2" steel would be very heavy.

FWIW, my biggest steel pads have a shipping weight of around 30 pounds, but I can stand on them with my 190 pound fat butt and they won't fail. The legs are 14 gauge (.080" thick) steel, and I guarantee aluminum of that thickness would fold like a cheap suit. I'd suggest when anyone is building a pad, they should consider the limits it will be put to, and use the proper sized material, be it steel or aluminum.

 

[DRAGON64]

Good points, and an excellent post. I used aluminum for the brackets of the original steel legged pad, and they are pitted from corrosion. They cleaned up nicely with a Brillo pad and some elbow grease.

The steel in the original was .062 - .080 like your materials, I don't remember exactly, as they were tossed out and subsequently picked up by a scrap metal collector. The aluminum legs I have now are .125" and should work very well from a strength standpoint.

I truly wish I could go with stainless steel hardware, but will have to make due with galvanized for now.

Question; what drove you to build your 1st, 2nd or even your 3rd pad? I mean before you decided to start marketing a pad to the rocket crowds?

On a side note, even cheaper and lighter, my HPR PVC pad held up my 300 lb frame (fat butt) and has been a work horse at a number of launches...1.5" goods. Neither here nor there, but PVC is a great builders source and I am Off topic on my own thread....for shame on me.

 

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Good points, and an excellent post. I used aluminum for the brackets of the original steel legged pad, and they are pitted from corrosion. They cleaned up nicely with a Brillo pad and some elbow grease.

The steel in the original was .062 - .080 like your materials, I don't remember exactly, as they were tossed out and subsequently picked up by a scrap metal collector. The aluminum legs I have now are .125" and should work very well from a strength standpoint.

Yep, should be plenty strong.

I truly wish I could go with stainless steel hardware, but will have to make due with galvanized for now.

Oh boy, I priced stainless for a customer once that wanted a large pad. The material alone was going to be almost $400!

Question; what drove you to build your 1st, 2nd or even your 3rd pad? I mean before you decided to start marketing a pad to the rocket crowds?

I built a few for our local club (TARS) and then took one up to my now "home" club (JMRC) and the guys there really like them. A few wanted to buy one then, so I built them some. JMRC then asked me to rehash their existing mid power pads so I did that, after which they told me I should be selling them. At the time Yellowjacket pads were no longer available, and "A Launch Pad" company was bilking folks out of money by taking payment and not producing, so one thing led to another and here we are today. The design has changed drastically form the original version, mostly through suggestions from fliers and such. Chris Pearson, of NCR Rocketry fame, offered some very good suggestions that are still in place today. He was very helpful with getting me in a position to sell them as was Art Upton of Boostervision. Art helped me with marketing and the web site, the guy's a wiz when it comes to that stuff.

On a side note, even cheaper and lighter, my HPR PVC pad held up my 300 lb frame (fat butt) and has been a work horse at a number of launches...1.5" goods. Neither here nor there, but PVC is a great builders source and I am Off topic on my own thread....for shame on me.

LOL! PVC works, it holds up well, is easy to get and offers a lot of versatility. I'm working on a multiple station launch rail for low power stuff built out of PVC that should be pretty cool.

BTW, I checked out the tower trailer you built on your site..... WAY COOL!!! Too bad you're on the left coast, you and I could get into some trouble.

 

[DRAGON64]

I am hoping to finish this tomorrow, as the mast has finally arrived in the mail...but until then, I found this older photo from my hybrid days (when I owned all of the GSE etc.) which showed my original pad being readied for use.

Photo courtesy of Ray Cole

Ray's son and Lee "The Hard Rock'n Rocket Paint Master" Brock were looking on. The event was a 2-day B'Ham Rocket Boys launch from Sept 2005.

 

[DRAGON64]

BTW, I checked out the tower trailer you built on your site..... WAY COOL!!! Too bad you're on the left coast, you and I could get into some trouble.

What tower trailer? I launched my Level III from an awesome tower trailer last year, but it was not mine...it belonged to Hope and Carl Hicks from the PhoenixMissile Works group down in Biringham, AL. That trailer is a work-of-art Full remote control!

 

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Ohhh... OK, it was on the Dragonworks link on your post.

 

[Peartree]

Ohhh... OK, it was on the Dragonworks link on your post.

Really? That link goes nowhere for me. All I get is a note that says "This website parked FREE couresy of GoDaddy.com" and a list of more sites with the word 'dragon' in them.

 

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Yep, it does that today. The link *was* working last week.......

 

[DRAGON64]

My Domain is being transferred (already has) and the website is being re-worked...sorry, I had not looked at it in a long time.

Yes, the tower-like pad was of a PVC design from years ago...and it is still going.

 

[DRAGON64]

Weather cooperated, and I managed some time to finish the pad; here are some pics:

Pic 1: Mast and stand-off installed

Pic 2: Mast and installed rail in prone

Pic 3: SA-14 Archer in prone

Pic 4: Archer up

Pic 5: Excalibur up

I love this design, it is light, strong, and looks down right nice!