For the guys who have built this rig:
http://launchpad.hofle.com/
Is there an issue with how tight the launch rods are? Is there wiggle and play in them? If so, how did you solve this? I'm going to build one I think.
For the guys who have built this rig:
http://launchpad.hofle.com/
Is there an issue with how tight the launch rods are? Is there wiggle and play in them? If so, how did you solve this? I'm going to build one I think.
I have added a drill chuck, that I picked up at my local hardware store, to the bottom pvc pipe. The chuck holds the rods tight and there is no wiggling and the rods will not be pulled off by the rocket. I am currently working on a design for my rail. I have had no problems with this design. It is worth the time and money to build.
I built and use that pad. I like it. Just drill the holes for a snug fit. The rod holes are drilled through both sides of the top horizontal pipe and through one side of the bottom horizontal pipe so that they rest on the inside wall of the bottom pipe. The rods are supported at spaced apart locations so the only slop in the rods is the rod flex itself which is independent of the base.
I put the rod holder in a drill press vise to make sure all the holes were on axis and parallel.
As I recall, for the small diameter rod my drill bit was not long enough so I drilled the top pipe for a tight fit, slipped the rod through until it rested on the lower pipe and then heated the rod with a torch and pushed it through one wall of the lower pipe.
I also got a few of the cheap rubber jawed metal mini clamps from Home Depot and put those on the rods between the two horizontal pipes just in case so if a rocket hung on the rod it wouldn't lift the rod out. The little clamps also help with routing ignition wires.
I have a couple of 1/8 inch rods and a 1/4. You could go up to 3/8, possibly 1/2.
Last edited by Neuport; 1st August 2012 at 06:00 PM.
I constructed mine last night. I just need to dremel out the square holes for the carriage bolts and I'm done. Super easy and a great pad.
Chrisudy and Green Jello:
We have a gallery for home made launch pads. I would encourage you both to share pics of you pad there.
I remember thinking this was a cool design when I saw it several years ago but I forgot about it until now.
__________________
John A. Lee O.S.L.
Alamo Rocketeers NAR Section 661
NAR 87285, L1 8 March 2008
TRA 03040, L1 8 March 2008
Photos of the "Fleet": http://www.flickr.com/photos/23694991@N03/
I used to tell Mom, "...I want to fly rockets when I grow up!"
She said, "Make up your mind, you can't do both!"
I finally finished putting on a basic paint job. Also I molded some 1/2" PVC nubs over the two holes for the launch rods where the blast shield will sit. It will never again look as nice as it does today.
Dave
TRA #:14201 Level 0
Current Project: Wildman Jr.
Current Project: Orbital Transport Upscale
Current Project: Wildman Darkstar Stealth
Well done
-James Hamilton
L2
https://sites.google.com/site/disasterguysrocketry/
I love America but I also love Canadian bacon, whiskey, and MOTORS.
Indeed!
Very nicely done.
Kit (AKA Cranky Kong)
Total Total Impulse as BAR: 7,753.69 Ns (Equivalent to a 51% M motor.)
=| Calirado, Colofornia...what's the diff anymore? |=
Looks great! I keep mine in a bag from a folding chair. I put the launch rods in a length of 1/2 PVC with end caps pressed on and it all stows in the chair bag.
What should be taken into account when painting PVC? Is there a special type of primer or paint to use. This looks great.
__________________
John A. Lee O.S.L.
Alamo Rocketeers NAR Section 661
NAR 87285, L1 8 March 2008
TRA 03040, L1 8 March 2008
Photos of the "Fleet": http://www.flickr.com/photos/23694991@N03/
I used to tell Mom, "...I want to fly rockets when I grow up!"
She said, "Make up your mind, you can't do both!"
Dave
TRA #:14201 Level 0
Current Project: Wildman Jr.
Current Project: Orbital Transport Upscale
Current Project: Wildman Darkstar Stealth
Wow! Really nice work on the pads.
Jeff Vegh
TRA# 03011
NAR# 92403
Oh sure. I took about 1" lengths of 1/2" PVC and rounded one end with a Dremel tool so they wrapped around the crossbar. Then I glued them in place with the PVC cement and painted.
Dave
TRA #:14201 Level 0
Current Project: Wildman Jr.
Current Project: Orbital Transport Upscale
Current Project: Wildman Darkstar Stealth
I see. You cut a saddle in each stub for a pipe-to-pipe saddle joint to space the blast shield away from the top horizontal rod support.
- Did you do that to protect the horizontal support or for aesthetics?
- Did you use the saddle joint rather than "T" fittings because you thought of it after the support mechanism was glued up, to save cost, or because it looks less cluttered than the "T" fittings would have? You could have opened up "T" fittings so they would slide over the pipe.
Whatever the reason, it looks nice.
Check out my latest projects:
Estes Vagabond - Dual Deploy
Estes Ventris - Missile Livery - Dual Deploy
Scratchbuilt LPR for my daughter - Mermaid theme
Blackhawk 38 - Setup photos and info see also posts #50, 53, 60
1. A little bit of both. It seemed like a good idea to create a raised base for the blast shield to sit on and I liked how it looked.
2. I thought of adding them after the whole thing was built, so T fittings wouldn't be possible. But you are right. Reaming out t-fittings so they could slide down the whole pipe would have been easier and more exact.
Dave
TRA #:14201 Level 0
Current Project: Wildman Jr.
Current Project: Orbital Transport Upscale
Current Project: Wildman Darkstar Stealth