Since my rocketry interest rekindled some 18 years ago, I've been intrigued by Model Rocket Industries (MRI), since they were based in my home state, in the city of my undergrad studies, Madison. I've picked up a small number of kits, with the intention of building at least some of them. The first design that really caught my eye was the Zeus, but haven't come across one in kit form yet.

I've slowly collected parts to be able to build some MRI clones, starting with the Zeus. The plans are here, which have been a great help: https://www.oldrocketforum.com/showthread.php?t=17596 . Though I have some BMS T20Q tubing, thought I'd use parts from a Quest Gamma-Ray kit, the upper half of which I'm saving for different MRI/AVI clone. I started with the parts list from the plans, and used the catalog to fill in some question marks.

From the Quest Kit:
- 20mm Body tube, cut to 6" (per 9" catalog length)
- 18mm Engine tube
- 18mm Engine Block
- 2" launch lug (estimate from plan drawings)
Nose cone from eRockets
- https://www.erockets.biz/semroc-bal...-sem-bc-t2032c/
Stuff from my stash
- 3/32" fins cut from plans
- 17" long flagging tape streamer (per catalog)
- Screw Eye
- 1/8 oz. Lead Weight (Semroc WL-7)
- 3' Kevlar (Apogee 100#)

The only mods from original are the motor block (the original was in the 20mm tube), and a Kevlar shock cord. Fins have been papered and edges sealed with CA, since the shape leaves fragile fin tips when cut per the original fin sheets. I plan to use the orange/blue color scheme from the color header card, probably manually masking & painting. That's all I have for now, parts are bagged ready for the build.

Several threads have been helpful piecing together info on MRI (and MPC/AVI), so thanks to those who did that work. Thought I'd put all the helpful links here, in date order. Some only have a post or two about MRI, with info I didn't see elsewhere:

What rocket company was in Mineral Point, WI?
Central Rocket Company info?
Quest body tube wall thickness
Help me find my first rocket!
Happy Birthday, Myke Bergenske!
National Model and Sport Rocketry Collection Blog
MPC History
MRI Starter Set / MRI History
AVI -- Early Literature

And Chris' blog:
https://modelrocketbuilding.blogspo...s-answered.html

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__________________
Paul
If we weren't all crazy, we would go insane - Jimmy Buffett
NAR #87246 www.wooshrocketry.org

Just happens to be one on eBay now.

Link: https://www.ebay.com/itm/2259494923...k9SR_bi5sGd Yw


Earl

__________________
Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

My very first kit was an MRI Wac Corporal. Still have it, not up to my current building skills. Testers wood glue was not a good choice to attach fins, but as a young person, I did not like to wait on white glue to dry. I did finaly clone it as well.

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I went through an MRI phase a few years back. I cloned a Zeus, but in cheap and dirty style instead of paying attention to exact tube sizes. It's a fairly tiny rocket, so I made mine 13mm powered. The first flight was fine on a 1/2A, but the A3 flight last fall was unstable from the moment it left the rod. Best thing about it is the Iron Man paint job, purely unintentional. I also built the Lambda 8, Phobos and Theta 37, none of which I've managed to tree yet. I have the parts for another one, but I can't think of the name. Did they kit the Lepus?

__________________
Bill Eichelberger
NAR 79563

http://wallyum.blogspot.com/

I miss being SAM 0058

Build floor: Estes - Low Boom SST Semroc - Marauder, Shrike, SST Shuttle

In paint: Canaroc - Starfighter Scorpion Centuri - Mini Dactyl Estes - F-22 Air Superiority Fighter, Multi-Roc, Solar Sailer II, Xarconian Cruiser Semroc - Cyber III

Ready to fly: Estes - Solar Sailer II Semroc - Earmark

I had a MRI Zeus and Lepus "back in the day" (AVI sales period) but did a terrible job on them and likely never flew them. Still have the instruction sheets! (Also had a MRI Flare, which I built and flew. Sturdy kit!)

I cloned a MRI Lepus about 10 years ago, using an original MPC body tube and a cone which was either Semroc or MPC. (In reviewing the photo, that cone might actually be from my Flare! I scorched the paint trying to vacuum-form a new cone in shop class around 1975. I must have kept it and sanded it smooth for use on the Lepus.)

It was a very zoomy kit, flying very high on A8-5.

I made the mistake of flying it on a C6-7. Kept track of it during its ascent, and even saw it descending into a area with a lot of obstructions to sight, and several ponds. Never recovered it.

I have parts (Semroc origin) for another Lepus and a couple of Zeus-es.

The tricky part with the Zeus is those odd fins. If you don't paper them think you'd need to use very hard C-grain balsa, and cut and sand them carefully.

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__________________
NAR #27085 - Oregon Rocketry - SAM

Yes they did!

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__________________
Paul
If we weren't all crazy, we would go insane - Jimmy Buffett
NAR #87246 www.wooshrocketry.org

FYI
The seller just made an offer to me for $10 off this kit. I don?t need the kit but if someone else here who might want it made a similar offer back to the seller they?d probably go for it.

Earl

__________________
Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

If I do that, I've clearly embezzled some funds.

__________________
Bill Eichelberger
NAR 79563

http://wallyum.blogspot.com/

I miss being SAM 0058

Build floor: Estes - Low Boom SST Semroc - Marauder, Shrike, SST Shuttle

In paint: Canaroc - Starfighter Scorpion Centuri - Mini Dactyl Estes - F-22 Air Superiority Fighter, Multi-Roc, Solar Sailer II, Xarconian Cruiser Semroc - Cyber III

Ready to fly: Estes - Solar Sailer II Semroc - Earmark

I don?t think anyone here would rat on ya.

Earl

__________________
Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970