The first Centuri Engineering catalog I got my hands on was the 1971 edition. I was building and flying Estes and MPC kits for a few months, and the biggest motor I was aware of was the "Mighty D13," so I was kind of blown away by the catalog's "Large-Scale Rocketry" section.

I was able to scratch together enough for an Enerjet Nike Ram a couple years later, but still had the itch to own those fine looking Mini-Max era models. About 20 years I cloned the Jaguar, Explorer, Aero-Dart (Mk. III) and Hustler.

And . . . thanks to an auction at one of the last LUNAR launches I attended, got my hands on a Aero-Dart. The kit was incomplete (missing parachute, launch lugs, and kit instructions) so I tagged it as a build kit.

Well, I'm finally getting around to it.

* * *
The kit was shipped to John Fox of Evanston, IL in April of 1969. It was shipped Air Mail, so John didn't have the scratch to buy the full set, which included three Mini-Max motors.

He must have moved to the Bay Area somewhere along the way.

(I also have a built FSI Nova John donated to the auction . . . complete with mimeographed instructions! I sanded off the old paint job and refinished it.)

More later!

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__________________
NAR #27085 - Oregon Rocketry - SAM

Do please open the box and show us photos of the parts that you do have!

__________________
-Wolfram v. Kiparski
NAR 28643 - TRA 15520
MTMA Section #606 President

Part II. Parts!

The body tubes and balsa parts are in excellent shape.

I treated the cone and balsa coupler with filler and such years ago.

Centuri pre-installed the motor mount (which has great big thick wound paper centering rings) and the shock cord harness.

The wide black elastic shock cord runs in parallel with a very thin braided wire "secure cable." Because of its age and relatively short length, I'm going to get rid of the elastic. Instead, I'll get a ferrule and attach the secure cable to a barrel swivel, and tie a 6' piece of elastic to that. In other words, I'll use the secure cable as a shock cord mount. I'll wrap the cable with some kind of tubing at the point where it exits the body tube, to prevent zippering.

Yeah, no motor retention! You were instructed to wrap the Mini-Max or Enerjet motor with lots of masking tape.

* * *

(Wouldn't it be fun to go back in time to 1965 and present a NAR R&D report on through-the-wall fin mounting? And present Centuri with a upgraded version of an Aero-Dart that has that, motor retention, and a sensible shock cord arrangement?)

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__________________
NAR #27085 - Oregon Rocketry - SAM

Part III.

Instructions.

Attached are the 1971 version of the Aero-Dart instructions, which mention Enerjet motors.

The original sheet, which I have attached as a pdf, was used from when this model of the Aero-Dart was introduced in 1965 or so.

This kit would originally had the older one.

Something the same in both versions: They mis-spell "dowel."

I just noticed that the PDF mentions "Hercules" motors. These were a predecessor to the Mini-Max motors. Port-burning black powder F motors. It is possible that there is a late-60s version of the instructions that mention the Mini-Max motors, which had Metric measurements.

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Attached Files

	kf-12ac.tif (340.5 KB, 26 views)
	kf-12ab.tif (157.4 KB, 12 views)
	kf-12aa.tif (127.9 KB, 13 views)
	AeroDart.pdf (253.9 KB, 20 views)

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NAR #27085 - Oregon Rocketry - SAM

Part IV.

The Mark III Aero-Dart is not a difficult build. You glue on the fins and launch lugs, glue in the bulkhead, attach the screw eye, and finish it.

I gave the fins -- cut out of a printed sheet of good quality 3/16" balsa -- a good streamlining.

I plan on gluing a little patch of foil to the angled bit on the trailing edges, to make them a little more fireproof.

I might paint on some wood hardener, or thinned epoxy, before filling the fins.

Per my usual, I punched holes along the area where the fins will mount.

Oh . . . one other thing missing was the "Sil-Ray" reinforcing fabric. In the earlier version of the instructions, they suggested using airplane dope or white glue to attach this fine-grain fabric. I'm undecided what to do. I might find a fine cloth and epoxy it on, or use white glue.

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NAR #27085 - Oregon Rocketry - SAM

FYI

Here is a good grayscale scan of the 1971 instructions from my kit. This is a hard kit to get! Good luck on the build...will be following along!


Earl

Attached Files

	Centuri MiniMax AeroDart 1970-Inst2.pdf (793.6 KB, 26 views)
	Centuri MiniMax AeroDart 1970-Inst1.pdf (671.2 KB, 30 views)

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

Rocket-Brained Since 1970

Thanks, that is a much better scan.


I still have my unbuilt Semroc SLS Aero-Dart. I might keep that in the bag as a "pay for a kidney transplant" kit. (Not on its own, mind you.)

I'd love to know how many "Large Scale" kits Centuri sold trhough the years. The fact that you had to pay through the nose for shipping big motors likely limited their wide appeal.

* * *

P.S. My first Aero-Dart clone (below) was made using the Aerotech 1.88" tube. Just a fraction of an inch wider than the old ST-175 Centuri tube. I turned the balsa parts, and used BMS (I think?) to make the balsa centering rings.

If anyone wants to clone the kit, that might be the way to go. Perhaps someone can get some cones and bulkheads turned.

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NAR #27085 - Oregon Rocketry - SAM

I might not have much to say, but I'm paying attention.

__________________
Bill Eichelberger
NAR 79563

http://wallyum.blogspot.com/

I miss being SAM 0058

Build floor: Estes - Low Boom SST Semroc - Mini Aero-Dart, Shrike, SST Shuttle

In paint: Canaroc - Starfighter Scorpion

Unflown: F-22 Air Superiority Fighter, Jayhawk, Multi-Roc, Solar Sailer II, Microsonde 3 Payloader, Aerobee 300, Cyber III, Scrambler

Part VI. Fins!

I'm going to apply and sand two coats of thinned fill-n-finish, then follow up with several coats of brush-on balsa filler. Get 'em nice and shiny. I avoid filling the last 1/4" or so by the root edge, so glue and fillets can get a good grip.

I have an old handkerchief I'll cut apart and use for the fabric reinforcement.

Also:

I checked a couple of hardware stores for tiny cable ferrules, so I can attach the secure cable to a barrel swivel. No luck! Even Amazon couldn't help.

I found a video on tying cable to a swivel, using a square knot and an overhand knot. The cable is very stiff, but I'm going to have a go at it. I'll need pliers to draw the loop taught. I'll pass the cable out back through the motor mount, trim the cable so it doesn't cross the top of the body tube, tie on the swivel and elastic shock cord there, then heap it on forward.

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NAR #27085 - Oregon Rocketry - SAM

A short length of some small diameter brass or copper tubing from the K&S rack, perhaps?

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE