Launch tower for sale
Jack
Hello folks –
I’ve been contacted by an old LUNAR member (who goes back to the Robertson Park days). He’s a mechanical engineer who wishes to remain anonymous and has a precision launch tower he would like to sell. He designed and built it himself but is no longer in the hobby. The full description with pictures is below. If you are interested, please contact me and I’ll put you in touch with him.
- Jack
Jack Hagerty, LUNAR #0002
Hotline: (925) 443-8705
"There has only been one Rocket Scientist, Isaac Newton when he established
his 3rd Law of Action/Reaction. Everything since then has been engineering" - me
Subject: Re: Model rocket Launch tower for sale
Hi Jack, here are the text and images for the “Monolith” adjustable aluminum model rocket launch tower. Please note that I try to keep anything model rocketry-related that I do publicly anonymous (as you can see here by the online moniker “Reynolds Slumber).
Please let me know if LUNAR itself or someone in the club would like to buy the launch tower. Would it be OK to ask for around $800 for it? If the interest wasn’t there, I was thinking of posting it on Rocketry Forum for sale for $1200. I know it’s a substantial chunk of change, but it is a unique, high-precision item (I’ve already spent many times its monetary value in storage rent since I made it!).
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“Monolith” model rocket launch tower, single crank instant diameter adjustment, CNC machined aluminum
This is, so far as I am aware, the ultimate model rocket launch tower. Features and specs:
- Single hand crank under the base sets the spacing of all three rails simultaneously, evenly, and rigidly using a parallelogram mechanism, adjusts in seconds
- 4' long rails, 1/4" thick, with recesses for thin (yet structurally stiff) sheet steel links for maximum fin allowance
- Rocket size:
- 3-finned rockets 1/2" to 5" in diameter
- 4-finned rockets 1 1/2" to 5" in diameter
- Fin span up to 12"
- Aft end of rocket supported by a stop screw
- Legs and hand crank handle removable for transport
Construction:
- CNC milled aluminum base, rail link recesses, and bracing panels
- Milled aluminum frame parts
- Sheet steel links, nickel-plated
- Lathed low-profile stainless steel pivots (made manually individually)
- Sheet steel blast plate
- Ball bearings under the blast plate for the jackscrew connection
The current condition is as seen in the last image. Maintenance needed and potential modifications:
- Replace 36 snap rings in 2 standard sizes (due to rust)
- Drill a slight increase in diameter in one of the leg retention screw holes (very easy)
- Could add a hole at the foot end of each leg for hold-down stakes
Sold as-is. The tower is fully functional now but would benefit from the above maintenance.
This was a unique and ambitious project to make, one which took over 100 hours of machine shop time plus additional design time spread across a year. This design improved upon just about every functional feature of the aluminum Apogee Medalist/BMS Gold Medalist launch tower from the 1990s. The recessed sheet steel link design makes it physically impossible for fins perpendicular to the body tube to hit the rail links, given the thickness of the rails. As an example, the depicted 4-finned model rocket has a BT-60 payload section and 3/32” thick fins.
While it is technically possible to disassemble the tower, it would mean that you’d have to fit it back together in the original configuration and align all of the pieces, so it’s much easier to leave it intact. That’s how it’s offered for sale, intact except that the legs and hand crank handle are easily removed. With those parts off, it’s a tight fit across the back seat of a full size sedan. Offered for pick-up only in the San Francisco Bay Area, no shipping. (If you want to get someone to pack it in a tall appliance box and ship it, that would be on you!)
Emma Humphries
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Anthony Cooper
Anthony M. Cooper
31120 Chicoine Ave.
Hayward, CA 94544-7432
VP and Membership for lunar.org
Cell: 510-589-5292
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William Kellermann
<tower - 3.jpeg>
This is, so far as I am aware, the ultimate model rocket launch tower. Features and specs:
- Single hand crank under the base sets the spacing of all three rails simultaneously, evenly, and rigidly using a parallelogram mechanism, adjusts in seconds
- 4' long rails, 1/4" thick, with recesses for thin (yet structurally stiff) sheet steel links for maximum fin allowance
- Rocket size:
- 3-finned rockets 1/2" to 5" in diameter
- 4-finned rockets 1 1/2" to 5" in diameter
- Fin span up to 12"
- Aft end of rocket supported by a stop screw
- Legs and hand crank handle removable for transport
<tower - 2.jpeg><tower - 5.jpeg><tower - 11.jpeg><tower - 12.jpeg>
Construction:
- CNC milled aluminum base, rail link recesses, and bracing panels
- Milled aluminum frame parts
- Sheet steel links, nickel-plated
- Lathed low-profile stainless steel pivots (made manually individually)
- Sheet steel blast plate
- Ball bearings under the blast plate for the jackscrew connection
<tower - 1.jpeg><tower - 10.jpeg>
To view this discussion visit https://groups.google.com/d/msgid/lunar-general/CAM899rP%3Dmj%2BPuCy-7O65nmRccJggDkhAvwJzRqRSvSn3EEnusQ%40mail.gmail.com.
Gene Engelgau
- Regards
Web: http://fruitychutes.com - Professional Aerospace Recovery Systems
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Jack
Hi Gene –
Emma doesn’t have it. It belongs to a former LUNAR member who is looking to sell it.
"If God had meant us to be a spacefaring race,
He would have given us a moon" -- Krafft Ehricke
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Jack
It’s for lower power models, like for competition.
"The wonderful thing about standards is that there are so many of them to choose from" - Grace Murray Hopper, pioneering computer scientist
From: 'William Kellermann' via LUNAR General <lunar-...@googlegroups.com>
Sent: Monday, August 18, 2025 7:44 PM
To: lunar-...@googlegroups.com
Cc: General LUNAR <lunar-...@googlegroups.com>
Subject: Re: [LUNAR General] Launch tower for sale
A tower with 4’ rails is pretty limited.
To view this discussion visit https://groups.google.com/d/msgid/lunar-general/8C6FF733-C58C-44B0-9402-84FC7E589FBB%40me.com.
William Kellermann
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Jack
Absolutely correct. Mostly used if you don’t want a launch lug on the side of your model.
"Rocket science: A century of making everything else look easy" – James Marino
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