HPR Launch Pad for 1010 Rail

[pathtouch]

Figured I'd share photos of my 1010 launch pad. All you need is a jig saw and basic welder. Although with a few more bolts or self tapping screws you could probably build without welding if you're without one.



It's made out of 14-gauge 2" square tube, some L2x2x1/8 angle, 1/4"x3" flat bar, and 1/2" hardware. It's all steel and these were thicknesses I could easily cut and weld with what I have. The blast shield is just a concrete paver I got cheap because the corner broke off, which was actually ideal for me. Note that the top bolt hole in the vertical tube is slotted and allows for 15 or so degrees of adjustability to account for wind or to tip away from the flight line.

It mostly follows the John Coker pad design which is just beautifully elegant. My own changes were going with double bolted connections, and swapping the vertical member out for angle iron instead of flat bar to gain some stiffness.

The 14 gauge tubing was easy enough to cut with a jig saw.


Also key was this little trick. I cut a piece of 1/2" copper into a sleeve about 0.020" wider than the tubing, so this acts as an axle at the top pivot point. This allows you to set the angle you want to launch once, while still allowing the rail to fold down for loading. Originally you'd lose your angle once you loosened the bolts while tilting the pad.


Example of it in action. You can see I also found 1/2" pull pins from the local tractor supply / farmer's union store, eliminating the need to use a wrench every time you load.


I also made the rear leg adjustable with a carriage bolt and nut. The other legs have holes that I just filled with nuts and bolts so there's some extra hardware and also to keep it level since the center piece has hardware sticking through the bottom.


All in all it's about 34 lbs and collapses into to a fairly compact foot print for travel.


And we've launched J and K powered rockets no problemo. For any rockets pushing more than 30 lb I may consider anchoring to the ground or just laying sand bags on the legs. We'll see. I do wish I made the tube the rail attaches to about twice as long. This way the rocket's could be stood off the ground a good distance without loosing the bottom foot or so of rail length.

 

[Samarth Barshi]

Is the rail stiff by itself? Is there no support structure required for this?

 

[pathtouch]

Good enough for 20 ish pound rockets so far.
I’ve sent a 4” diameter fiberglass rocket off it on a K550 no problem.

 

[pathtouch]

Is the rail stiff by itself? Is there no support structure required for this?

Stuff enough for me. Actually I have a video of a 4” fiberglass rocket going off this in a K550. Check out around 6:10 into the video here:

 

[Rocketjunkie]

Steel is going to rust unless you protect it well. The pads I built in 2002 use solid aluminum rectangular bar for legs. (The rest is all 300 series stainless including the bolts.) They are still going strong after 20 years of club launches with no maintenance. They will handle rods from 1/4" to 1" and 1010 rails directly. I'd have to go to the storage unit to get pics of the one I saved for my own use. ICBM/ROSCO has 6.

 

[Handeman]

Is the rail stiff by itself? Is there no support structure required for this?

We use 8ft. extensions of 1010 rails and 10 ft. 1515 rails with no additional support. The rails are stiff enough. The question becomes, how stable is the pad they are attached to. If there is going to be a lot of sway and whip in the rails, it's usually because of flexing in the pads and how the rails are mounted.

Also, our pads are all 1010, and 1030 rail base with steel L and angled blast deflectors that act as structural parts of the pads. We had to replace the angled section of the blast deflectors that the exhaust hits after about 9-10 years.

Since the pads sit in the field the whole launch season, we will dig around them and level them so there is a slight lean away from the flight line when they are set out in the fall. They are not adjusted for winds.

I wouldn't recommend this design for personal pads that get setup, tore down, and transported often. For a club setup where they can sit in the field all season, or at least stored at the field, they would be excellent. These sit outside in VA year round, Oct. to Apr. in the launch field and the rest of the year stacked outside our sea container. They are now are 13 years old and still going strong.




There is a 1/4" pins through the two support 1010 sections and the bottom of the rail as the pivot point, and another near the top to lock the rail upright.

 

[Sparky]

Nice looking rocket set up and I love the top hat in the lower photo.