DIY Metal Launch Pad w/instructions to build

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tooth

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Like a lot of folks I wasn't thrilled with the current crop of prebuilt or homemade PVC launch pads. For about $35 I came up with this steel angle pad that I'm quite happy with. Will outline my process in case anyone else here cares to make one for themselves.

01 overview.jpg


Parts:
02 steel angle.jpg
*1-1/4-in x 1-1/4-in x 5-ft L Steel Perforated-Round Angle, $25 at the hardware store. They had two different weights (or thickness) and I went with the heavier one. Glad I did.

03 lug.jpg
*2 Aluminum Lay-in Lug, AWG 14-4 to hold launch rod. $1 each from hardware store

*Anything from a 1/8, 3/16, or 1/4" cold rolled steel rod for another five bucks

*Layer cake pan for blast plate. .99 from thrift store

*various screws and nuts ~$5 - $8 (I sort of lost track, lol)

04 mockup.jpg
I’m not at all experienced working with metal like this, so I started by building a cardboard mockup. Cereal or cracker boxes work great for this kind of thing. I decided to shoot for a 30 degree spread to the legs, and a finished length of 16” to 18”.

CRITICAL: please always use gloves and eye protection when you work with metal. Flying sparks, chunks of metal, and tiny slivers in your hand can ruin your day.

05 cut layout.jpg
Using the cardboard as a template, I transferred the 30 degree angle to the steel sections, then using one of those cheap hand grinder/cutoff wheels I cut the angle off from one side of the L shape. Remember your trigonometry (or cheat and just measure lengths off the cardboard mockup like I did)- the flat side you will bend down needs to be longer than the 18” to make up for the angle. The first two legs I cut 18 ¾” off the bar. When I laid it out I set the longest point of the angle to be 18” from the back so the extra ¾” length bent down to pretty much flush with the point.

The third leg I made 5” longer (still setting the longest point of the angle to be 18”) so I had metal to cross over the other two and bend up 90 degrees for the launch rod. Save the flat piece you cut off this one as it will become your rod holder.

06 scare.jpg
Pro tip: to get a nice straight bend on that top section, lightly score across the bar with the grinding wheel or a hack saw. It bends down a lot easier, and far straighter when you do.

07 epoxy.jpg
To strengthen the base I used epoxy glue to fill between the flat and the angled piece. When this dried I was amazed how much more stable the tripod was so I recommend you do this step.

08 knob.jpg
I needed to trim off a corner of the leg that went on the bottom of the stack to get the holes to line up. When you have that, put a ¼” clamping knob through the center hole, and a ¼” wing nut on the bottom. The idea being easy setup and breakdown with no tools required. I used epoxy to glue the wing nut on the bottom so I never lose it. Spread the legs out to roughly 120 degrees apart and you have a solid tripod mount!


09 leg.jpg

10 leg.jpg
Your tripod will now be balancing on 3 points. If you always launch in dirt that is probably ok, but I wanted a little more spread for hard surfaces to increase the stability. Lay a scrap of 1” lumber near each foot and draw a line parallel with the ground. Cut off at the line and now you have a much broader surface to set on the ground.

Next I went over all the metal parts with the grinder and smoothed all the crude cuts I had made. I told you I have no experience with this kind of thing so the cut lines were REALLY janky. I also ground off all the sharp corners. Lastly I went over everything with emery cloth to be sure all the metal edges were truly smooth.
 
11 rod holder.jpg
Taking the flat piece cut off the longer top leg I rounded the bottom edge, then drilled two holes to hold the lay in lugs. Be sure the lugs are straightly aligned to hold the launch rod.

11a.jpg
Connect the bottom hole to the bend in the top leg with a wing nut so you can easily adjust the angle of the rod for the wind without tools.

12 safety cap.jpg
For the safety cap I glued together a license plate nut and an auto panel fastener- parts found in those little pull out trays in hardware stores with all the other weird connectors. Those little drawers are also where you can find clamping knobs and thumbscrews. The windsock is from a plastic wrap that came on something shipped to us.

13 thumb.jpg
I replace the regular screws on the rod lugs with thumb screws. Again to make adjustments in the field as simple as possible. No tools needed to change the launch rod to a different diameter.

13a blast.jpg
A hole drilled in the layer cake pan was about all needed to turn it into an adequate blast deflector.

14 finish.jpg
Before painting I rubbed everything down with acetone, lightly sanded all the surfaces with emery cloth, then sprayed on primer. Finish coats with gloss Rustoleum.

Other than painting and waiting for the epoxy to dry this is literally an afternoon project for anyone with a $14 grinder from Harbor Freight. The finished launch pad has a 28” wide footprint and weights just under 3.5 lbs including a 3/16” rod. It can be disassembled without tools and packed up in no time. If I can build this, trust me – you can too!
 
There was some confusion about those hardware boxes I mentioned. You can find them in just about any hardware store. They typically are stacked in banks with several drawers in a row.
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PXL_20220831_152546149.jpg
 
my pleasure OverTheTop. I hope someone can benefit from the idea. I'm sure some of you can make major improvements to my approach.
 
my pleasure OverTheTop. I hope someone can benefit from the idea. I'm sure some of you can make major improvements to my approach.

The only improvement I would make is welding the metal joints instead of epoxy. That is just because I happen to have a small >$150 Harbor Freight 120V wirefeed welder (less than $100 back when I bought it) that works pretty well on thin metal like that.

Thanks for the instructions and post.
 
Nicely finished product. I like that you built a mockup, first!

I know that you took safety precautions, but I would still avoid using that steel angle as the construction material, especially for newbies. Way too sharp and pointy. PVC is much easier to work with for LPR-MPR pads.
 
good point Buckeye. I probably over-engineered it, but it is doing a great job. And I love how easy it is to set up in the field.
 
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