Clustering the Classics...(More Power Tim!)

[Micromeister]

jflis has reminded us of our Upsale/Downscale activites with our favorite classic models. How many of us also look at a kit and think "Man this thing is just begging to be clustered." i.e SR-71 blackbird, Deep space transport, Geo-Sat HLV, Greyhawk to name just a few. What about the BT-80 & 101 based models, Super big bertha, Optima, Saturn-V. Lastly those Upscales we've been talking about. Clustered BP or Single motor AP...Humm!
Let see what we've been doing. Heres a few clustered pics to get ya started

 

[Micromeister]

heres a few of the smaller ones i was talking about, and why sometimes all does not go as planned.

 

[rbeckey]

I just got a Crayon yesterday! What did you do for fins? I can't see them in the picture. Plexiglass? Lexan? How did you mount them? I was thinking of a convertible 29mm single/24mm cluster engine mount based in a BT 80 tube and coupler.

 

[eugenefl]

Wow! What beautiful liftoff on the SR71! Now that is cool! So lemme ask, do you just add more noseweight to compensate for the odd motor arrangement? Seems logical. That's too bad it crashed. I totally loved it.

Makes me wonder if anyone has ever clustered the Estes Space Shuttle. Functional boosters would be waaaay too cool!

 

[Micromeister]

Rbecky:
Can't see em.. that was the idea they are .063 (1/16") clear Lexan. they are epoxy rivit mounted, useing 3/32" holes in both the crayon base and the fin. then a 1/4" fillet each side. She's flown about a doz. times without damage, recovery is a 36" nylon Hemi-chute sawn by my better 2/3rds. (Hey! Any woman who let's their hubby paint, epoxy, and all manor of other smelly things in the basement all these years and still make my chutes is way more than a better half.) Back to the crayon. What size tube do you have? the 5D is a 4.5" dia. I also have a smaller 2.5" that flys well on 2D's but was under powered with one.

Eugenefl: This was the 5th flight of that perticular SR-71, I have since converted another ducting the outboards into the main body with 1/8" x1/4" rectanular brass tubes to eliminate the center Oops possibility. unfortunately this model suffered a cato on its second flight and was distroyed. 3 C6 motors Kicks butt in the SR. To answer you queston on additional nose weight. Oh yes! I found a good rule of thumb for this process. Add the total weight of any added components, rings, plugs, motor mounts, ducting materials, and a tiny bit for adhesives, then add one half of the mass of the largest motors you will be adding beyond the kit recommended motor. This process has worked out well for 2, 3 and 4 extra motors over the years, with NO surprises on launch day.
The Shuttle Stack is a very finicky configuration, Much care must be taken in allowing or the additional Offset thurst you are contemplating. She will likely loop into the ground if not counter balanced. George Gassaway flys a stack RC controlled, you will be hard pressed to convert the estes shuttle stack to a cluster.
Hope this helps

 

[loopy]

Gemini DC is another prime candidate for clustering. I think there's one or two examples on EMRR, if I'm not mistaken. I've also wondered about clustering the Phoenix and Executioner, but I'm happy with my changes for launching on AP right now. In the future, however...possibly a Big Daddy in there too...hmmmmm.

Mark

 

[gerbs4me]

All those cluster pics are really cool.

 

[Micromeister]

I found a 4 pic page of an Old favorite of mine, Way back. the original model was designed to fly an odd evet back in the 70s, called Quatrant. The modeler had to fly one model for 4 flights and 4 events, pd,sd peewee payload and spot landing. if you lost your model on one of the flights you were DQ'ed. This Little Beasty was designed for B Quadrant. back then it was flown with 3 A3-0s, and 3-A3-4s and a B6-6 core.
I rebuilt this model, changed the mounts to take the 13mm A10-0T and A3-6T's in the sustainers, and a B6-6 in the core What a COOL flight!!! I hope you guys can see the seperation smoke trails!

 

[rstaff3]

Way cool micromister. How did you ignite the outboards?

 

[trogdor]

micro that is really cool. Love the engineering in that! I think I found my spring project! Been looking for a cluster and/or two stage to do! That and the fin-tab-booster-spinning no-upper-stage-fins TAO two stager in sport rocketry are next! JIMZ has the plans. I've had em a few years but never really tried it seriously....

Check it out here

https://www.dars.org/jimz/mrn/mrn3701f.jpg

and here

https://www.dars.org/jimz/mrn3701.htm

 

[Micromeister]

Dick:
As with all my cluster activities, I alway use a 40amp power relay built into my solar launcher base,(That 12"x12"x10" brown wooden box under the rocket. Connected to Hi amp/hr wet cell battery, by #8 stranded copper to the line side of the relay, the 8 clip-whip is #18 thhn stranded copper 18" long, exceedingly little voltage and current drop (resistance) with this system. Each igniter is daisy chained positive, negative,positive, negative always with an even number of micro clips, when the control curcuit launch button is pushed, a 12v dc coil electrically pulls the the relay contacts closed dumping all the juice into all the igniters very nearly instantly, I'm been using my own igniters, consisting of 30ga nichrome wire and an AP/polyurethane/alum. pyrogen. It's just a tad slower then some of the commerically available stuff, and I think is gives the Igniters just at extra split second to burn ensuring all motors get a 1n/s flame The system works with all other igniters.....BUT since about 98 when Estes started experimenting with their igniters, I haven't had the warm fuzzy feeling about them for clusters. Ya gotta test every one before, and after installing them in the motors. I have a diagram of motor wirings for small clusters I recommend somewhere, it was part of an BP clustering R&D I've be conduction since Naram 35 1/4A -6C Cluster/Alt. My 6C got 666m at ECRM in May, If I'd gone out west I'm sure she'd have cracked 750m
I have it scanned but it may be to large to post here.

Towelie: I can't take credit for the original design, I'm just one of the goofy folks that made it work. the original spoof was drawn I think in june or july of 1970, and published in Model Rocketry Mag.

 

[Micromeister]

I had this launch series pic, in the Cloning the classics thread, but thought it really belongs here as she's a cluster first and an unscale second.

 

[Micromeister]

When Narhams decided to host Naram-35, Cluster-Altitude had just been added to the pink book events, so we said what the heck and through 3 x1/2A clu-alt. into the mix. We were very disappointed when then National contest board chair Matt Steel, allowed airstarted (Step Staged) motor models in cluster-altitude comptetion. that the steped staged model won was no suprise. but it sure ticked me to the point of writing an Rule change. That mistake has been rectified and I've been conducting a 1/4A - C cluster-Altitude design study ever since. This beast ws to be an R&D for Naram-43 but I just couldn't get myself into the presentation paperwork Since were talking about clusters here I thought you might get a chuckle out of some of the off the wall designs, but thought I'd start with my 6C model, that briefly set the national record at 666m and a model porposed by Tim @ apogee built at the same time, same materials and flown on as identical conditions as I could control. the twin of the green model was tracked to 578m. both flew on 5 C6-/ 1-C6-7 all motors on both models ignited, green-a, snapped just about the pods on landing, both were streamer recovered on 4"x 40" mylar streamers. the only damage to Orange-a, was a tiny chip in one fin and the paint burning around the exhaust ports.

 

[Micromeister]

Heres a goup shot of 5 of the 10 original designs for 1992-93
for 3x 1/2A cluster altitiude. The model on the far right will be done now differently in that the paper should a 11 degrees will be replace by two 7 degree taper in line pods. finished to a super high gloss and slick as oil.

 

[jflis]

excellent!

I love clusters and am thrilled to see that others do too.

frankly, with seeing cluster kits all but vanish from manufactures offerings, I was a little nervous putting them in the catalog. Needless to say, the whole rocketry community has shown me that it's the right thing to do *S*

Although, I do recall having conversations with many folks in the past wondering why i still played with clusters when it was so much easier to just buy a single, larger motor...

...they'll never understand...

 

[Micromeister]

Jim You've sure got that right!
they will never understand, but seems like, they may be the only way to go in the very near future.

Here's my micro 3 motor

 

[Micromeister]

Here's a goup shot of 6 of the 12 different configurations tested for 4xA cluster attitude, again working left to right, beginning withe the first model to survive ending with the model or models used at 2 ECRMs on the right.
The 10.5mm blue model tracked to 351m. Man I miss those 10.5mm motors!

 

[SPONGE]

You guys are right, some people just don't seem to get how much fun clusters are! I've been so facinated with them that every scratch built rocket I have made has been a cluster. But, they do seem to be getting bigger.

Micromister, On that wiring diagram you posted, is there supposed to be a clip at each spot where the polarity is marked? So, for the 3 motor wiring there would be four clips right? I have been having a devil of a time trying to get three Estes E9s to light. I've only got 2/3 the last two tries. The attached pic is the last attempt. It flies ok on only two, last time the chute did not deploy fully, and now the rebuilt version is 8in shorter. A cool video of my 4xE9 can be seen at https://www.aarg.org/pix/launch021005/index.html

Loopy's right, The Gemini DC would be an easy fun cluster to make. When my stock one is ready, I'll rebuild it a 3x18mm.

 

[Micromeister]

Sponge:
That is correct the whip will always have an even number of micro-clips, But!!! more important for consistant cluster ignition ya gotta use a relay and move the igniter power supply as close to the igniter as practical. preferably directly under the launch pad. I have a "range box" relay add on diagram somewhere, all parts are radio shack, I'll do a little search and upload it this afternoon. and please check your igniters before and after installing them in you motors. just cause there new out of the pack, doesn't mean they are good. I'm finding more and more rejects slipping through Estes Quality control I've stopped useing their igniters for clusters.
Hope this helps.

 

[Micromeister]

Sponge:
Here's that hand drawn relay add-on diagram and parts list. I use this with my tower at competitions. I've used it with a wide aray or systems, with my own 26amp gel cell at the pad. Normally is have the RSO continuity check count down a bare igniter to make sure the range system don't close the relay with the continuity lamp or buzzer, if it burns the igniter I request a continuity launch. push the launch button Then turn on the KEY.
I've only had to use this request once since 96 so the add on does work.
Hope you can read the list

 

[SPONGE]

Nice diagram. I've been thinking about building one of those for a while. But since I started launching all of my big stuff at club events, I decided to spend the time building more rockets instead. I think you hit the nail on the head with your comment on the estes ignitors. So I have to ask: Are there any comercially available ignitors that will provide better reliability for both BP and AP?

 

[Micromeister]

Sponge:
Unless someone else out here knows of a source we are pretty much stuck. of the three Quest tigertails, Aerotech Copperheads, and Estes Solar ignitors. I'll have to go with Estes.
I usually buy 12 extra 6 packs with my bulk motors orders. Open and sort them into groups, Standard single motor use, Cluster motor, and those that will fit my micro-maxx motors. Storage is in the tall empty pill bottles with a flattened cotton ball covering the bottom. Don't want to break, or damage the pyrogen on the good ones we just found. It is also a good idea to test each one, I will insert a diagram of a simple pocket tester you can make for about 4.00 bucks. all the parts are raido shack.

The other choice is to make your own, Firestar, and Igniterman or two kit forms I know if, Both are kind of expensive, they can dry out, but are fairly easy to use, the igniterman material absorbs moisture from the air very quickly, even when dipped in the provided "sealer" I've had batches of these units be completely useless in less the 60 days. keeping them in a sealed heavy duty plastic bag helped a little, but not much. Firestars have been very good. Or for single motors there is always "back to the begining" 30gage nichrome wire. no pyrogen required, but you must use a 12v hi amp battery.
Hope this helps

 

[Micromeister]

This is the last of the clu-alt construction Pics. a close up of the open side pod on my second place 5B clu-alt at ECRM, This was before I realized a 1/4" balsa bulkhead just above the exhaust port would let the covers be reduced to Cardstock, instead of .015 waferglass and epoxy to hold them in place while reducing about 12g from the overall weight. I only wish I had this revelation before my contest flight attempt. I blew off 3 of the 4 pod covers but still managed to take second place
Here's a close up of the pod so you can see how they are cut.

 

[Micromeister]

One of my great fortunes is to work for a major Sign manufacturer. We deal with a host of trades and disciplines and all manor of materials. One that came along recently is a vinyl coated REAL Gold leafed sheet product and several Marble look vinyls. I just had to use these in a rocket.
As this stuff adds a good amount of weight I decided I would use a cluster of 2 D12's to power the "Golden Raider" with black marble transition and fin covers.
Because of the 273.5g weight I thought a 30" Hemi nylon chute would be needed to bring her down gently. Boy was I wrong!!!
Her first flight was very nearly her last. 2 D12-5 motors put the model WAY up there, and that 30" chute must have reduced the sink rate to under 5 ft /sec. We actually saw this heavy thing catch a thermal, I chased the model for over an hour, giving up and heading back to the range in dispare. Then a couple hours later a kind family from nearly 8 miles down wind of the launch site, returned her to me! Putting your name,address and phone in the model does Help sometimes.
Here's a still pic of the model.

 

[jflis]

oh man, beautious, that's for sure! Glad you got it back!

 

[Micromeister]

I forgot this one..
our club does flight demonstrations at a couple local airshows, and one of the problems has alway been getting stuff large enough to fly on a fairly tight flying field, namely a main runway, with trees on one side and the spectator line on the other. one very problematic type is Helicopters. So I built this beast. and equipped it for two missions. one as a Demo bird flying low and slow on a cluster of 3 D12-3 motors and second illuminated the rotor tips with 12000mdc orange leds and 3v lithium button batteries to Open one of the clubs Waivered Night launches. As bad luck would have it my "test" flight on 3 D12-3's in Oct. suffered a Cato on the first flight distroying the movable fin-can/ motor mount. I haven't gotten back to repairing the damage
Over all the model stood 76.5" tall, had graphite rod reinforced 1" thick x 60" airfoiled blue styrofoam rotors and 1/64 ply covers 3/16" foamcore fins. she tip the scales at 1386g.

 

[Micromeister]

I found a better shot of the 3D and original laser-X models, Sitting their display stand, after all the decals were applied

 

[jflis]

sweet! That is one of the centuri kits that I **really** wanted, but could never get...

 

[Micromeister]

Why yes it is, and I think I still have one in the bag
I only wish the centuri/estes folks could bring back 4 models and keep them in the line, Mars snooper which they did bring back briefly, Orbital transport, recently released but not to stay in the line, Centrui SST, Way cooler then the OT, and the Interceptor, which I'm told be estes can't be re-released because the Plastic parts dies were destroyed years ago. apparently far to much money to retool for a limited run....HUMMM than don't make it a limited run!! I'll bet if they kept these 4 in there line up, they wouldn't have to worry about a bad year and it wouldn't bother me a bit as a collector either.

 

[Micromeister]

I think I posted this pic in the Odd-Roc thread, but It is a 2 motor cluster just because I like clustering,
This model is from my "Flying condiments" collection "the Salt & pepper stack" flying on a pair of A10-3T's this little bugger flys pretty well. The shaker top hides the 12" plastic chute