TRIPOLI PREFECTURE # 138rimworld.com/tripoligerlach/downloads/2013-03-04.pdf · 2013-07-05 · high...

July 2013 Vol 03 No 04

TRIPOLI PREFECTURE # 138

www.tripoligerlach.org

TRIPOLI GERLACH NEWSPAGE 2

MAGAZINE STAFFEDITOR & LAYOUT:

CONTRIBUTING STAFF:

GUEST EDITOR:

OFFICE:

Tom Blazanin

Chris PearsonDoug Gerrard

Joe PscolkaKen Good

Tripoli Gerlach748 Galloway DriveValencia, PA 16059

Tripoli Gerlach does NOT promote nor certify anyactivities presented here as safe nor appropriate toall readers of this Publication. Information is foreducational purposes only. Tripoli Gerlach, itsmembers & officers, the authors of articlespresented and the Tripoli RocketryAssociation, Inc.are not responsible for reader’s activities, conductor participation in the use and pursuit of any contentpresented.

DISCLAIMER

ON THE COVER Robert Dehate (center ontrailer, facing camera) and crew raise his 185-pound, two-stage rocket on the rail prior to flight atthe Black Rock Desert on September 30, 2011. TheBALLS launches at Black Rock finds many largeprojects such as this never seen at other locations.

Photo by: Mark Canepa

JULY 2013

JULY 2013 Vol. 03 No. 04

PUBLISHED EXCLUSIVELY FORTHE MEMBERS OF TRIPOLI GERLACH

and anyone else interestedAll Content Copyright ©2013 by TRIPOLI GERLACH

TRIPOLI

Tripoli Gerlach was founded as a National Prefectureunder the Tripoli RocketryAssociation, Inc. Devotedto Research Rocketry and the Black Rock Desert areaof Nevada, we welcome all qualified TripoliMembers having a Level 2 certification or higher.

Our Executive Officers are;

Tom Blazanin (003)Prefect

Valencia, PA

Dave Rose (7126)Treasurer

N. Huntingdon, PA

Deb Koloms (9021)Secretary

Watertown, NY

If you have anything to contribute in the way ofinformation, articles, photos or whatever, please sendthem to Tripoli Gerlach Headquarters. Visit ourWebSite on-line at;

[email protected]

[email protected]

[email protected]


Well it’s July and LDRS is upon us. If you haven’tregistered yet the deadline is July 10th. After that theprice of fun goes up on the Playa. To register go to thew e b s i t e w w w. l d r s 3 2 . c o m a n d c l i c k o nREGISTRATION in the menu.

Good news is the BoD has approved NAR flyers arepermitted to fly on Tripoli Research days under theirNAR Safety Code. This opens LDRS 32 to be five daysof Research Flying. All Tripoli and NAR members arefree to fly to their Certification Levels under the rules oftheir organization.

BALLS 22 Registration is now open on their website:www.balls22.com click REGISTRATION on theirmenu. Deadline for BALLS registration is September14th - or pay a higher fee on the Playa.

HAMSTER DANCE III is set for September 19th, theThursday before BALLS. Once we have the BALLSRange set up we will all caravan down to Smoke Creek,the site of the old Amateur Rocket activities in the daysbefore Tripoli. Don’t miss out on this fun, easy and laidback event. Sign up at: www.hamsterdancelaunch.com

WHAT’S UP

PAGE 3TRIPOLI GERLACH NEWS

Nearing the end of a serene day at LDRSat Lucerne in 2010, TRATreasurer BruceLee and I were left behind to work withthe Discovery Channel crew (who werestill filming) while the rest of the BoDdeparted to prepare for that evening'sTRA Members' Meeting /Dinner. As westood on the lake bed while the TV folksprepared a take, a loud whooshing ofrocket motors and a huge smoke cloudappeared at one of the away cells, and notfrom a rocket taking off. As people at thecell were seen running out of the smoke,Bruce and I almost simultaneously said,“That's an accident.”

And indeed, an accident it was. I did notimmediately appreciate how intimatelyknowledgeable I would become of the circumstances. Iwould spend the next several hours focusing on workingwith the LDRS launch organization to help ensureemergency medical responders attended to several injuredparties, caused by the unintended ground ignition of rocketmotors of a large clustered multi-stage project that was beingprepared. But I also gathered information, and wouldbecome the point person for the inevitable insuranceclaim/investigation that would follow… and also the lawsuitthat would be filed almost a year later by one of the injuredpeople.

Although I could devote many pages (as I did) to fully reportwhat happened, leave it to say many issues in rangemanagement and rocket prep safety should have been bettermanaged at LDRS 29, and absolutely must be bettermanaged as we proceed to fly increasingly inherentlydangerous rocket projects. In fact, it became a case study inhow not to manage the flight preparation of a significanthigh power rocket.

There is indeed an unspoken code in which we tend to letpeople we regard as “experts” proceed with what they aredoing. But that is an error, and we must be brave, mouthy,rude, outspoken enough to speak up to stop something thatlooks like it's not the correct thing to do. I was part of a goodexample of this at BALLS last Fall, when the TripoliPittsburgh/NASSA team was getting ready to fly theirambitious Phoenix P-motor project. Several of us had justcompleted the tasks required to get this large aluminumrocket on its launch rail and ready to be fired, and we hadretreated to a “safe distance” from the rocket….. except thatin actuality, we had not. TRA President Stu Barrett, whowas also out on the playa assisting had in fact moved to a safedistance, and came forward to those of us who hadn't,yelling, “C'mon you guys – you're not far enough away from

a research P-motor for cripes sakes!” Stuwoke us up. I was embarrassed that Imyself, former TRA president andconstant safety nag had to be told this…but Stu was right. A fact reinforced whenafter we had moved to an approveddistance, the motor catoed, blowingburning chunks of propellant geyser-likeover the playa. Yes, even those who“know better” sometimes don't, and weare all obliged as rocketry colleagues tospeak up when needed and break theunspoken code.

Summarizing all this, it really comesdown to a few key considerations. Firstoff, all applicable safety codes must befollowed at all times, and not just “sort of”

followed. Second, we must be vigilant to those areas notalways explicitly defined in a safety code. Things like howmany people do we really need or want out at a launch pad,who is wandering about our range and how are wecontrolling who is going where, do we really understand ourbig, complex projects (or our simple ones) and are wescrupulously following correct procedures, or are wegroping about or taking short cuts.

Finally, we have to treat our rocket projects like full-blownspace vehicles. High Power rocketry has grown up now –way up. In many cases, we are flying rockets that are beyondthe capability of what some civilized countries could managehalf a century ago. We can't think of flying high-powerrockets as a sort of jazzed-up picnic in a park with the kidsflying a few Estes model rockets. We have to think andbehave like professionals, like we were an actual space flightcompany doing this for a living, and directly responsible forany bad outcomes. If we think of modern, high-powerrocketry this way, we introduce a mental discipline that willbe resistant to laxness and neglect, and committed tofollowing flight procedures that are safety code compliant,and which manage risk responsibly.

Unless all high-power flyers move our collective riskmanagement to the levels required by the rockets we areflying, we are living on luck and the law of averages. It willonly be a question of time before the really big accidenthappens that kills someone, and we can watch mournfully ashigh power rocketry disappears in a blur of lawsuits,restrictions, and prohibitive legislation. Perhaps that LDRS29 incident was the sobering example we needed to see, tohelp us commit to the actions that will permit high powerrocketry to continue onward, as it has done since it was begunso many years ago.

EDITORIALKEN GOOD

Never be complacent, when in doubt speak up!

JULY 2013

PAGE 4 TRIPOLI GERLACH NEWSJULY 2013

Everyone who goes to Black Rock whether to launchrockets, go hunting, film commercials, land sail,explore or just heading for California the hard way hasto have met Bruno. He’s the biggest business in townowning the Bruno’s Casino, Bruno’s Restaurant,Bruno’s Texaco, Bruno’s Trailer Park, Bruno’s Motel,Bruno’s Cattle Ranch, Bruno’s Farm and Bruno’s WhatEverYou Need I got It ForYou!

With all of his accomplishments his most outstandingfeature is his ability to remember people. He mayhonestly not remember your name but he willremember YOU. Have a conversation with him onceand he will remember you two, three years later. He’llremember your job, your kids, your health. If you talk tohim about it he’ll remember you.

Bruno was born Giovanni Bruno Selmi on July 20th.1923 in Lucca, Italy, about 60 mile away fromTuscanny, Italy. As a boy in Italy he was into BicycleRacing and was even awarded a prize by the Pope forwinning a race. You should hear the story, Bruno’s agreat story teller - except you really have to payattention as he speaks broken English.

His stories are boundless; like when he ran his truck offthe road and in his words. “Ima bounce ana bounce

You would think after being in this country over 65years he’d speak better English! He does however,speak perfect Spanish, ( ya sure!) and we sorta think hespeaks English way better than he presents.

Bruno came to the US in 1946 following his twobrothers Dominic and Joe. He

anabounce ana bounce ana bounce!

arrived in the U.S. and

worked at his brother Dominic’s ranch in Dayton,Nevada just East of Carson City, until he got a job at thedefunct Gypsum plant , then called Portland, .

Bruno’s brother Joe had a bar in Gerlach, which stillexists although Joe passed away several years ago. Inthe evenings after work Bruno would hang out there tohear a girl named Francis sing. Francis became Bruno’swife in 1950.

They had one child, Lena Skeekie Selmi. Today weknow here as Skeekie Courtney.

Bruno bought the Longhorn Bar, which is now Bruno’sCasino & Country Club, in 1952. Ever after that its beenan uphill expansion of acquisitions for him.

This year Bruno turn’s 90 and his mind is still a steel trapof memories, so unlike most people his age. Once youmeet him you can’t help but long remember him too.

in Empire

BRUNO SELMI

Bruno with his current main squeeze, Mary.

TRIPOLI GERLACH NEWS PAGE 5JULY 2013

TO GERLACH

NIXON

NIGHTINGALE

2 miles

2 kilometers

NIGHTENGALEThe Black Rock area is peppered with mining areas fromyears gone by. Gold and Silver mines were abundant andnow just empty holes and shafts remain. Copper minesflourished for a while and most are now gone. Empire hasits Gypsum pit still “open” but without a processing plantit too will soon be a part of history.

The town of Nixon, south of Gerlach, was near home to arather large Tungsten mine. While the mine is now closedmuch of its existence still remains.

Tungsten was discovered in the Nightingale district in1917, and enough was found that they hauled it down to amill at Toulon, 40 miles to the southeast. In the early1930's they built a 100-ton concentrator on site but itnever got much of a workout. Tungsten production wasintermittent until World War II, but then slowed downagain until about 1956, when interest petered outaltogether.

While not as romantic or exciting as gold, tungsten has itsuses, and was particularly important during wartime. Itsuses in high speed metal-working equipment, steel,armor, and armor-piercing shells made tungsten a vitalwar commodity. Tungsten was in such short supplyduring the war that the War Production Board mandated


that all replaced automotive ignition points be returnedto salvage the tungsten in them.

Even more fascinating are the ruins of the MGL mineand mill, in the canyon about 7 miles north of the turn-offfor Nightingale. However, the road is washed out bad inmore than a few places, and the going can be hairy.

While the Nightengale area is where most people stayedand most of the Tungsten was mine, the MGLmine and

Up the road skirting the southern end of dry LakeWinnemucca you will find the ruins of this tungsten-gathering venture. Taking that road up the canyon willtake you to the mine site. Be advised this road requires a4WD vehicle.

The place is strewn with decaying buildings andpeppered with open mine shafts just begging you in. Donot enter. There are many places and objects of a historicnature.

The road is rough and desolete. Take water and other peoplewith you. Note the Ore Car Track.


mill is where the largest structures are found. It has a fewmine shafts but most impressive are the concretestructures still standing.

Looking much like an Indian Cliff Dwelling the peoplewho built it added Deco Art to its character thinking thiswas to be a long term venture.Which it wasn’t!

Directions: From Fallon, west on Highway 50 toFernley; north on SR447 to Wadsworth and proceedingto Nixon; proceed north 1.8 miles, turn right on localroad; proceed 11.7 miles and take right fork 10.6 miles.

This gigantic structure was an Ore Concentrator use torefine Tungsten. Now it's home to Ghost Past.

What’s left of the Loader that dumped the Ore into waitingtrucks for the trip to the mill in Toulon.

The people who built this place tried to add style witharched dorways and canted walls.


THE ARCHOne of the neatest sites to see heading for the Nightengale area is natural. It's a stone arch located about half waythere and on the west side of the “road”. While you can’t drive up to it you can park and walk. You’ll need a sharpeye, or binoculars, but it can be seen from the road and is worth the hike. Luckily, like the Nightengale Area, its noton Indian land so you can enjoy it all you want.

The Black Rock area gets major rains almost every year.In 2006 Heavy waters ran down the Granite Mountainsnorth of Gerlach and was the major cause of the GuruRoad destruction. It also continued into town andthrough Bev’s MINERS CLUB, nearly wiping it out.

This year the much needed rain, which helps heal theBlack Rock playa, struck south of Gerlach about 31miles north of Fernley and destroyed Route 447. Not toworry, the Road Crew should have it fixed by the timewe get there!


You will often see chemicals in fireworks and propellantformulas that look like these:

Aluminum, atomized, 22 micronAluminum, -325 meshAluminum, -325 mesh, spherical, 22 micron

Do you really know what those particle sizes reallymean? What is really being described? When they say"-325 mesh" and "22 micron", what's the difference?And why does it matter to you?

Well, it can definitely help you to know how the particle"size" ratings get assigned to metal powders. Most ofthe size ratings come directly from the wholesaler ormanufacturer. But every so often we buy surplusmaterials which may not come with any additionalinformation about the manufacturer, the size or shape ofthe powder.

The first step in the identification process is a visualinspection.You may be surprised how much you can tellabout a sample just by looking at it. By observing theflow characteristics of a powder, and how it feelsbetween your fingers, you can approximate particle sizeand shape. If you have experience with metal powders,for instance, you can often tell if a sample is granular(rough feeling), or atomized (round particles, feelssmooth, pours and flows quickly and smoothly). If youcannot feel any particles between your fingers, you canassume the powder is probably finer than 200 mesh, oreven less than 325 mesh (written as "-325 mesh.")

The next step is to verify those assumptions thoughquantitative and qualitative testing.

To determine if a material is appropriate to be used in agiven formula you'll need to know the particle's shape

(morphology), size, and distribution (granulometry).Shape, as shown above, is easily determined under amicroscope and classified as atomized (spherical orspheroidal), granular, or flake.

Particle size is reported in one of two ways: either bymesh size (large and medium particles, generally largerthan 325 mesh) or by microns (very small particles).

US mesh size describes the number of openings per inchin a screen. So if a material is listed as -60 mesh it will allpass though a 60 mesh screen (the minus sign in front ofthe 60 means that all particles are smaller than 60 mesh).Conversely, if the material is described as +60 mesh, itwould mean that all particles would be retained on a 60mesh screen and are therefore larger than 60 mesh.

But mesh sizes can only go so far. After a point theindividual wires that make up the screen are so closetogether it is no longer practical to measure usingscreens. In practice, particles smaller than 325 mesh areusually described in microns. A micron is onethousandth of a millimeter, or one millionth of a meter.The unaided human eye can see particles of about 40microns. Smaller than that, you need magnification.

There is no truly accurate conversion from mesh size tomicrons, because the wire thickness' in screens vary allover the place. But approximate conversion tables arecommonly used anyway. (In the table below, screensizes of smaller than 600 mesh are shown, even thoughthey don't exist in practice.)

"Mass Fraction Analysis" is used to determine large-to-medium size particle distribution in a sample. Thepowder is sifted through a set of nesting screens, eachwith progressively smaller openings (higher mesh

Why use two measurements?

PARTICLE SIZES EXPLAINEDJOE PSCOLKA

TRIPOLI GERLACH NEWSPAGE10 JULY 2013

numbers). By measuring the percent of material thatremains on each screen, we can classify a material by itssize distribution.

If you were to sift a Magnesium-Aluminum product(described as 180-325 mesh) through a stack of 180mesh, 200 mesh, and 325 mesh screens, a mass fractionanalysis might yield a particle size range that looks likethis:

+180 Mesh 26%180-200 Mesh 31%200-325 Mesh 21%-325 Mesh 22%

If the 180 mesh size was critical to your formula, youcan interpret this to mean that 26% would remain on the180 mesh screen (larger then 180 mesh) and 74%would pass through it (be smaller than 180 mesh).

Mass fraction by sieve analysis is a very helpfulmethod of classifying coarse-to-medium particles, butwhat about the really small stuff?

When the average particle size is around 50 microns,sieve analysis is no longer practical, and doesn'tadequately describe the particle sizes. Several methodsare commonly used to measure really fine stuff:Gravitational Sedimentation, Laser Light Diffraction,Optical Light Microscopes, Scanning ElectronMicroscopes (SEM) and Transmission ElectronMicroscopes (TEM). The most accessible method to anamateur is an Optical Light Microscope.

So how is a particle measured with a microscope? Doyou need some kind of tiny ruler? As funny as thatmight sound, that's exactly how it's done. Themicroscope can be fitted with a gizmo called a ReticuleMicrometer. After it is calibrated, it can be used tomeasure the size of individual particles in a powdersample right down to 1 micron.

But just because you can measure it, that doesn't meanit's a simple task.

US MESH1020406080100200325400625

12502500

MICRONS200084140025017714974443720105

Sure, measuring spherical material is fairlystraightforward. After all, you're really just measuringthe diameter of little balls. But what about flake,granular, and spheroidal samples? Digital imaging andsoftware can drastically decrease the time needed toperform measurements and reduce error rates. But itappears that most if not all of the automated equipmentmeasures any particle shape as if it is spherical. Becauseof this, there is not really a standard method forassigning a particle size.

Selecting the method seems to be based mostly on whatyou'd like your results to state. Below is an imaginaryparticle and three circles representing differentmeasurement methodologies.

In the first example the measurement is across thesmallest dimension of the particle. This method mightbe used to describe the particle in terms of its reactivityby describing the particle in the smallest possible size.Method B might be used conversely; to describe theparticle's largest dimension.Arguably the most accuratemethodology would be using example C, where anaverage size is calculated

No matter what method is used, the results wouldnormally be presented to you, the end user, as anaverage size (3 micron), a particle range (3 to 15micron) or a frequency distribution (30% <5 micron,10% 5-10 micron, 60% 10-15 micron), or somevariation thereof.

So why does particle size or shape matter?The shape and size of a particle has a huge impact on itsreactivity. Flake particles have a large surface area thatcan be in contact with an oxidizer when compared witha spherical particle. Granular particles often have sharpedges that can ignite more easily than the smooth,round edges of an atomized powder.

Selecting powder with a different particle size or shapecan create a wide variety of changes in motorperformance, such as burn time, specific impulse,chamber pressure, etc.

Motor makers: Right now, as you look at the aluminum

A = 3 micronsMinimum Diameter

A = 13 micronsMaximum Diameter

A = 8 micronsMedian Diameter

PAGE 11TRIPOLI GERLACH NEWS JULY 2013

powder options from a chemicals suppliers list, you areprobably asking yourself: "what is the differencebetween spherical and spheroidal aluminum?" Or, forthat matter, "what does it matter that a particle shape isgranular, or flake, or atomized?"

Funny you should ask. I was just about to tell you.Herewith follows:

Before you embark on this area keep in mind thatparticle shape is not the only factor influencing how ametal powder will perform in a motor composition. Thesize of a particle of metal, whether it is coated or not, andother factors are just as important as particle shape.

Particle shape matters mostly because of its impact onpyrotechnic composition reactivity. Think about it.Which is easier to light, a 3 x 3 inch piece of paper or a 3x 3 inch piece of plywood? Chemically they're almostthe same thing. But the little, bitty edge of the paper is alot easier and faster to light than the edge of theplywood. And that's what separates the flakes from theatomized - ease of ignition.

Whether you are trying to make a rocket fuel, a flashdevice, a glitter fountain, a flitter star, or a long-tailedcomet (I know, those are fireworks), your success willdepend in part on using the right particle shape. So paycareful attention to the type of aluminum (or other metalpowder) prescribed in your motor composition. Ifparticle size or shape is not specified, and you are new tomaking motors, then it's a good idea to ask someoneknowledgeable. Using the wrong one might be a wasteof time and money, or could even be dangerous.

The following photographs show the most commonparticle shapes used in making fireworks. The scale onthe bottom of each photograph shows a 200-micron longscale for your reference (that means 200 millionths of ameter, or a little bigger than a grain of fine, pesky,popcorn salt for all you who insist on watchingtelevision and munching popcorn in bed).

In the top right photo notice how "edgy" the aluminumflakes are. These thin edges heat up and ignite fasterthan the rest of the particles. Flakes, because of thisedginess and the fact they offer the greatest surface area,are generally the most reactive particle shape when usedin pyrotechnic compositions.

Granular (ground) metal particles, as shown in thesecond photo down, have a characteristic, gravel-likeshape. Like flakes, they have a lot of sharp edges, too.

Particle Shapes 101:

Flake-Shaped Aluminum Particles(Magnified 100times)

Granular-shaped ferro-aluminum particles(magnified 100 times)

But they do not offer as much surface area, and so willnot be quite as reactive as flake powders.

Atomized, spheroidal aluminum particles(magnified 200 times)


Atomized particles come in two basic shapes:

those that are almost perfectlyround called spherical, as shown below.

those thathave irregular, rounded shapes, called spheroidal,shown bottom left and

Atomized, spherical titanium(magnified 100 times)

Notice that the spheroidal particles on the lower left alsohave "edges", those irregularly shaped extensions yousee in the aluminum shown. But because they arerounded, they are not as reactive as the flake andgranular material.

Spherical-shaped particles range from being perfectlyround, shown in the titanium photo above to almost-round, as shown with the aluminum particles below.These are the least reactive particle shapes of all, withvery few, if any edges to take fire.

So, the bottom line is that all metal powders are notcreated equal. Whenever you are creating a newcomposite propellant composition, choosing the right

Atomized, spherical aluminum(magnified 500 times)

metal fuel's particle shape is critical. Spherical shapesare the predominant metals used in compositecompositions, however, some have had success withother shapes. Again, if in doubt, ask someoneknowledgeable.

US MESH345678101214161820253035404550607080

100120140170200230325400625

12502500

INCHES0.26500.18700.15700.13200.11100.09370.07870.06610.05550.04690.03940.03310.02800.02320.01970.01650.01380.01170.00980.00830.00700.00590.00490.00410.00350.00290.00210.00170.00150.00080.00040.0002

MICRONS67304760400033602830238020001680141011901000841707595500400354297250210177149125105887453443720105

MM6/7304.7664.0003.3602.8302.3802.0001.6801.4101.1901.0000.8410.7070.5950.5000.4000.3540.2970.2500.2100.1770.1490.1250.1050.0880.0740.0530.0440.0370.0200.0100.5

3rd Annual

www.hamsterdancelaunch.com

September 19th, 2013


PRELIMINARYINFORMATIONPreliminary Information Please refer to the previousarticle “How to Make an Igniter” for details concerningconstruction of a bridge wire-type igniter that will be usedin the construction of the dipped igniter.

Carefully mix together the igniter pyrogen formula asfollows:

4 parts magnesium powder or mag/aluminum(Works best with <50u/270-325 mesh powders)5 parts powdered potassium nitratE½ part silicon metal powder6 parts Plasti-Dip binder (red or clear only)3-4 parts toluene (if needed)

Plasti-Dip is an air-dried rubber coating dipfor hand tools and is available at hardwarestores such as Ace and True Value. Only thered or clear colors are usable for igniterconstruction because of changes inthe compound chemistry for differentcolors. The toluene needed to thin themixture is available at the samehardware stores as the Plasti-Dip or atSherwin-Williams retail stores. Do notsubstitute any other solvent for thetoluene.

Please note that the above chemical ratiosare a “starter” formula. The best ratio foryour pyrogen varies a lot on thequality/particle size of your ingredients. If

your igniter “pops” or flashes explosively instead ofburns, you’ll have to increase the amount of binder to slowthe reaction down, starting with twice as much binder.Likewise, you can add potassium nitrate to increase theburn rate if your igniter is too slow. The igniter shouldhave a burn time of about one second. Simply addmagnesium for more heat/slag, potassium nitrate for morespeed, binder to slow to down the reaction, or solvent toreduce the dip thickness.

You may ask “Why use Plasti-Dip?” It’s thick and workswell as a binder, it’s cheap, and one container of it will last

HIGH ENERGY DIPPED IGNITERS

Is there an alternative to purchasing high-priced pre-made igniters or having to stuff pyrogen intostraws if you want reliable ignition for your rocket motors? While there areseveral different companies that sell already made igniters or dipping kits, they seem relativelyexpensive. For a rather small cash outlay, and, if you make Research motors, using chemicals thatyou probably already have, you can make a dipping compound that will perform as well, if notbetter, than any commercially available igniter or dipping mixture.

Yes . . . there is!

WARNING! This igniter formula includes magnesium powder and powdered potassium nitrate. These twochemicals should never be mixed dry as there is the possibility of spontaneous ignition or explosion if they are.Fine magnesium powder itself is very dangerous and if spilled can form an airborne cloud that can flashexplosively. Do not attempt to work with these chemicals if you have had no prior experience with them.Remember to follow good lab technique and wear gloves and eye protection. Have a source of water or fireextinguisher handy. It is a good idea for people who are inexperienced in chemical handling to mix the chemicalsoutside, or in a garage and work with someone else present.

CHRIS PEARSON & JIM ROSSON

Various items needed to produce High Energy Ignitors


a long time. The silicon fillers in the Plasti-Dip create aglassy oxide that "splutters" during the pyrogen burn. Youcan duplicate this effect by adding powdered silicon toany other igniter formulation. The burning SiO2 “slag”seems to fuse to the propellant when it hits, and helps thegrain ignite. After much testing it was discovered thatslow and hot was the only 100% sure fire way to light anymotor formulation, even those difficult to ignite green,smoky or sparky propellants. If one is not trying to light anold swollen and oxidized White Lightning motor, or someother improperly stored propellant, there are a lot offormula variations that will work most of the time.

Low ambient temperatures also impacts amount of heatflux required, and this is where long and hot is mandatory.For a pyrogen to use in low ambient temps, you can mixtwo different particle sizes of magnesium (small flake foreasy ignition, and mid-sized spheres for heat retention andslower speed). It can also be helpful to add silicon powderfor higher slag content and longer heat flux duration incold weather.

1. Measure out the Plasti-Dip and dilute with toluene in asolvent proof plastic mixing cup or glass beaker. Carefullymix in the magnesium powder to the thinned Plasti-Dip. Itis very important to first completely mix the magnesiumpowder into the Plasti-Dip before adding the potassiumnitrate, as this will greatly reduce the risk of accidentalignition. This is called “wetting out” the metal, and thereshould be no powered magnesium anywhere in the mixingcup before adding the potassium nitrate. Use a plasticspoon for measuring the magnesium into the mixing cupand then discard the spoon. Do not use this same spoon tomeasure the potassium nitrate! You can now add thesilicon metal if desired. Add the potassium nitrate withanother clean spoon, discarding it immediatelyafterwards, and stir with a wood stick, adding moretoluene if necessary until the resulting mixture is smooth.

MIXING & COATING PROCEEDURE

2. The mixture should have a consistency that is not toothin, as you don’t want it to be dripping off the end of theigniter before it dries. Too thick of a mixture will make ithard to coat the wire and will result in poor bondingbetween the pyrogen and wire, and might be susceptibleto cracking with age.

3. Dip the igniter wire into the mixture, making sure themixture completely covers the nichrome wire. Hang thedipped igniter head down over a paper towel. If thepyrogen drips off, the mixture is too thin. Let some of thetoluene evaporate until the mixture thickens up and tryagain. Likewise, too thick of a mixture can be thinnedwith more toluene. Multiple dips of this pyrogen are notrecommended because the additional thickness can causethe pyrogen to “pop” rather than burn or blow the top ofthe pyrogen head off without igniting it. Try to get as thicka coating on the wire as possible with one dip. Don’tworry about the thickness of the coating when dipped, asthe pyrogen head will shrink in size as the solvent flashesoff.

4. After you’ve dipped the igniter wires, let them dry for24 hours. Because of the nature of the Plasti-Dip binder,the igniter will have a rubbery consistency which is verydurable and resistant to drying out or cracking and will notrequire any sort of “protection” dip to prevent crumbling.It can also be shaved with a razor blade to reduce thediameter of the pyrogen head if necessary to fit it into asmall motor nozzle.

5. Check for continuity and resistance of the finishedigniter once again using a digital volt-meter. Theresistance of the completed igniter shouldn’t havechanged. If using these igniters in a cluster, use ones withthe same resistance, or ones that are very close. It isusually a good idea to check continuity on the igniter onceagain at the pad right before you insert it in the motor. Useyour own DVM. Don’t rely on the continuity circuits (ifthey exist) of the launch pads.

Using electric matches as the pyrogen initiator eliminateshaving to construct the bridge wire-type igniter and cansave much time if you are constructing them yourself, orexpense, if you are purchasing them pre-made. Electricmatches will allow a faster ignition of the igniter pyrogenand propellant which is important when flying clusteredmotors.

One of the problems that many igniter compositions haveis that they are relatively insensitive and can’t be ignitedusing electric matches so bridge wire igniters must be

USING ELECTRIC MATCHES

Notable difference between flake and powdered magnesium

High Energy Dipped E-Match and Bridge Wire

Business ends of a commercial bridgewire igniterand electric match


used. If you need faster ignition for clusters or upperstaging and you’re uncomfortable with using thermite forcluster ignition, enhanced e-match igniters are the answer.Adding antimony trisulfide, bismuth trioxide, zirconiumhydride or lead tetroxide to the pyrogen compositionincreases the ignition sensitivity of the mixture enough tobe ignited using a “popping” type electric match such as aJ-Tec. Although other e-match types may be used, theymight not ignite the pyrogen reliably. Testing must bedone to check e-match suitability and pyrogen burn time.

Of course, zirconium is also a candidate for this task. Oneof the most common uses of zirconium in igniters is in amixture of metallic zirconium and potassium perchlorate,called ZPP. It is also known as a NASAStandard Initiator.

However, both zirconium and zirconium hydride areexpensive, about $1-3 per gram in reagent grade and it isnot a chemical that is available from pyrotechnic supplycompanies. Using zirconium hydride is significantly saferto use than metallic zirconium, which when finely dividedis pyrophoric, that is, it will spontaneously ignite from thefriction in the air. Many professional rocket people andchemists warn against using metallic zirconium for anypurpose.

Other chemicals that are cheaper and not as sensitive areusable. Bismuth trioxide can be used and is a safer, non-toxicreplacement for lead tetroxide. That and antimony tri-sulfideare all are used in fireworks and therefore can both be

purchased from pyro or hobby chemical supply companies.You’ll have to experiment with the amount of additionalchemicals in your particular mixture, but generally if youmix one part of any of them to every two partsmagnesium, you will have a pyrogen mixture that issensitive enough to fire from an electric match.

Coat the electric match in the normal fashion and allow todry overnight. No additional precautions are needed forthis igniter compared to the traditional pyrogen-tippedigniter. This pyrogen will easily fire with an electricmatch, providing a much quicker motor ignition and theaddition of all but the bismuth trioxide causes the pyrogento burn at a much higher temperature, making for fasterignition of those binder-rich smoky or sparky motors orother difficult to ignite propellants. You can also use thisdip with a bridgewire type igniter.

After the can of Plasti-Dip has been opened, it will slowlydry out even if the container is sealed. In time it willappear rubbery and cracked. To refresh the mixture,simply pour toluene up to the level of the material and let itsit for a couple of days and stir. You can do this as manytimes as needed until the Plastic-Dip is used up. Howeverit will be thinner than it was when first opened, and youprobably won’t have to thin the pryogen mixture whenmaking future batches. You’ll also have to increase yourPlasti-Dip amount to compensate for the thinning.

STORING PLASTI-DIP

An in depth article on the basics of making StandardIgnitors was published inVol.2 No.2 March 2012.It covers everything from wirewrapping to pyrogen composition. It can be retrievedfree of charge by visiting our WebSite:

TRIPOLI GERLACH NEWS


COMING SOON. . .

All you need to know about making your own E-Matches. Covers compositions and how to makeyour own E-Match Blanks really inexpensively!

Don’t Miss This!

www.rasaero.com


Thermite, when properly used, is agreat way to get almost instant ignitionof composite rocket motors, which isuseful when flying clusters or stagedmotors. However, thermite, inparticular, iron thermite, has a bad rapbecause of its sensitivity and fromsome well-publicized accidents. Its ee ms tha t eve r yon e know s"somebody who got hurt makingthermite." Copper thermite has many advantages overiron thermite, and manganese dioxide thermite is thebest candidate for composite rocket motor ignition.

Some safety procedures need to be observed whenmaking thermite. Of course, as when doing any kind ofResearch rocketry motor propellant work, eyeprotection is mandatory, as well as wearing latex ornitryl gloves and make sure to have a fire extinguisheror water source handy.

Mix the chemicals carefully on a sheet of paper byplacing them side by side and mix by picking up oneend of the paper at a time until the chemical are mixed.Do not stand over the chemicals when mixing. Use anti-static procedures such as grounding yourself andanything you might be using before pouring chemicals.This can be done simply by touching a grounded ACoutlet several times during the mixing process. If youare really worried about static discharge, you can use anelectronic grounding strap that attaches to your wrist.Do not use metal utensils for measuring chemicals ormetal containers for storing the finished product. Useweighing paper or a plastic weigh bowl on the scale.

It's a good idea to mix only the amount that you areplanning to use. The mixed composition will degradeover time, and it isn't usually a good idea to have anylarge amount of mixed thermite sitting on your shelfnext to other chemicals. Package in a delicate tissue

paper or saran wrap "burrito" with ane-match. Use in motors with largecores and nozzle throats to preventclogging. Do not use a home dippedmatch (using a composition such asMagnaLite) or commercial lyavailable dipped match like aQuickburst to try to ignite thermite.The e-matches you need must be thetype of that "pops" and does not

simply burn. Make sure that the ignition leads of thematches are shorted together before beginningassembly of the igniter, and remain shorted until theigniter is installed in the motor. Don't use on motorssmaller than a J or K, as the nozzle throats are generallytoo small to install the completed igniter.And of course,following basic igniter safety protocol, you do not wantto install the igniters until the rocket is loaded on thelaunch rail.

When using thermite igniters it's a good safety practiceto carry an extra e-match or igniter, a digital volt-meteror even something as simple as a 12v light bulb withwires attached when going out to the launch pad.Connect it to the launch pad ignition leads to confirmthat they are not hot before you install the igniter into themotor. This is actually a good protocol when using anytype of igniters. If using an e-match or igniter, make sureto do this away from the motor(s), the thermite igniter,your eyes or anything else flammable. Make sure thatyour hands or anything else that you want to keep arenot underneath the motor(s) when you hook up theigniter, just in case the igniter accidently fires.

Insert the igniter all the way to the top of the motor, andthen back it off slightly, so that it is positioned centeredwithin the core of the top grain of the motor.

Properly made and installed, a thermite igniter willprovide almost instantaneous ignition of your motors.

THERMITE BASIC USAGE PRIMER

Thermite holds a major usage factor. If improperly pursued much damage to property andbody can be created. This is not exaggerated. Use total caution when preparing and using

this. This information, like all research information we provide, is for knowledge base only.

CHRIS PEARSON


MANGANESE THERMITE FORMULATIONThe most energetic thermite mixture that one can comeup with (aside from exotic, expensive and unobtainableingredients) is a manganese thermite. This variety ofthermite can be easily made by using a mixture of veryfine powdered manganese dioxide and ~100-200 meshmagnesium at a ratio of 1.5 parts MnO to one part Mgby weight. The mixture lights easily with an electricmatch, and seems to put out noticeably more heat than aCupric Oxide/Aluminum, CuO/Al mix. It also doesn'tseem overly sensitive to electrostatic discharge, as it isdifficult to light with an open flame, and it is not shocksensitive

The reason a MnO based thermatic composition ispreferable to a CuO based thermatic composition in thisapplication is because the heat of formation is about35% higher: 1.15 kcal/g for MnO based versus 0.74kcal/g for CuO based thermite. As a result the reactiontemperature for the MnO based composition is abovethe boiling point of both MgO and Al O so thethermite creates a high temperature gas cloud whicheasily lights more of the motor surface and at a fasterrate. But this MnO mixture is hard to light.

This can be solved easily as Shidokovsky, a Russianchemist, notes that a mixture of the following issignificantly easier to ignite and still has a reactiontemperature above the boiling points of both the oxides

68% MnO + 17% Mg + 15% Al

experimentation has shown that using as fine a gradeAland Mg as possible is essential to lowering the ignitiontemperature. This can be a problem as fine Mg can't bereadily obtained because of shipping restrictions.

2

2

2

2

2 3

2

2

When lighting a motor to reduce the ignition time youhave to increase the heat flux at the grain surface. Thereare three important variables here:

1) the amount of material2) the burning rate of the material, and3) gas generation that could carry the heat away.

The Shidokovsky thermatic composition reaction isnear gasless (other than the flux state of the oxides) soyou are not going to exceed the loading pressure of themotor by using a more aggressively matched thermitecharge than you would using a CuO/Al basedcomposition.

The way to calculate the optimal amount of charge is tocalculate the amount of engine surface you want to light(the area of the core of the motor is a goodapproximation for this purpose) and use enoughcomposition to get 150 cal heat flux per squarecentimeter of motor surface.

2Al + 3CuO has a flame temperature of 2843 K andcontains 974 cal/g,

4Al + 3MnO has a flame temperature of 2918 K andcontains 1159 cal/g.

2Mg + 1MnO has a flame temperature of 3271 K andcontains 1322 cal/g.

This data comes from a long list of thermites in:

, by S. H.Fischer and M. C. Grubelich

2

2

Theoretical Energy Release of Thermites,Intermetallics, and Combustible Metals

CHRIS PEARSON

www.balls22.com

SEPTEMBER 20, 21 & 22, 2013


CARL GUSTAF PATRIK de LAVALHe was born in the Swedish province ofDalecarlia (Dalarna) in 1845. He was adescendant of a French family that cameto Sweden in the seventeenth century.Even as a child he was unusually cleverand ahead of his time. His studies werevery successful and he got a degree inengineering and also became a Ph.D. Atthe time of his invention of the separatorhe was employed at the Kloster works inDalecarlia, an important industrial estate.

Gustaf de Laval had manifold technicaltalents and produced a number ofinventions. Apart from the centrifugalseparator, the operational steam turbine isthe best-known. He came to acquire quite a reputationas both an inventor and an industrialist, and he was alsoable to influence many other contemporary inventors.Unfortunately his genius for technical innovation didnot extend to economics.

In 1875 he took a job as an engineer at KlosterverkenIron Works and shortly thereafter he developed acentrifugal device for separating cream. Needing moretime to perfect his device he resigned his position atKlosterverken, and after much persistence was able toobtain a small loan that enabled him to manufacture hisdevice. The device proved to be such a success that itwas not long before Separator Company, Limited wason secure financial footing. For his invention of thisseparator device and other labor saving devices fordairy farmers, de Laval has been called "the Edison ofdairying".

In search of a method to drive the centrifugal separator,which required high speeds, de Laval developed asteam turbine. The turbine was driven by high pressuresteam shooting through a cone shaped nozzledeveloped by de Laval, that is now used on rocketengines. Able to turn, at what at the time was afrightening speed of 24,000 rpm, the turbine had to bereduced to one-tenth speed to drive the separator anddid not prove to be useful for this purpose. Howeverthere were many other uses for the turbine and aseparate industry developed.

Not content to rest on his laurels de Laval wasconstantly seeking new inventions, including milking

The Man of High Speedsmachines and a process for treating lowgrade Swedish zinc ores, none of whichwere as successful as his creamseparator. During his lifetime hereceived many honors, including fromthe King of Sweden, the Cross ofCommander of the Order of Wasa andthat of Knight in the Order of the NorthStar and he was made a member of theRoyal Swedish Academy of Sciences in1886 and received its gold medal in1892.

In 1887, de Laval developed a small,high-speed turbine with a speed of42,000 revolutions per minute. He is

credited with being the first to use a convergent-divergent type of nozzle in a steam turbine in order torealize the full potential energy of the expanding steamin a single-stage machine, completed 1890. He alsoinvented various devices for the dairy industry,including a high-speed centrifugal cream separator1878 and a vacuum milking machine, perfected 1913.

De Laval's other interests ranged from electric lightingto electrometallurgy in aerodynamics. In the 1890s heemployed more than 100 engineers in developing hisdevices and inventions, which are exactly described inthe 1,000 or more diaries he kept.

Also unfortunately the only thing we as rocket scientisthave come to appreciate from de Laval is the rocketnozzle which bears his name. While the mathematics ofthe de Laval nozzle is a crucial part of our rockettechnology it seems de Laval will go down in history,not as a rocket scientist, but a milk man who found awayto separate cream from cows.

During his lifetime Gustaf de Laval acquired 92Swedish patents and founded 37 companies. Hisinventions were to create work for millions of people.Gustaf de Laval died on February 2, 1913. Hismemorial was engraved with the inscription: "The Manof High Speeds".

A de Laval Nozzle (or convergent-divergent nozzle,CD nozzle or con-di nozzle) consist of two sections.The first is called the Converging Section, the area

The de Laval Nozzle

closest to the propellant. This section's cross-sectionalarea decreases to a minimum. The second area is calledthe Diverging Section. It faces the rear of the motor andit's cross-sectional area increases from a minimum. Thepoint of minimum area is called the Throat.

It is used to accelerate a hot, pressurised gas passingthrough it to a supersonic speed, and upon expansion, toshape the exhaust flow so that the heat energypropelling the flow is maximally converted intodirected kinetic energy. Because of this, the nozzle iswidely used in some types of steam turbine, it is anessential part of the modern rocket engine, and it alsosees use in supersonic jet engines

In rocketry applications the purpose of the nozzle is todirect the exhaust gases and increase their velocity.

The Speed of burning propellant exhaust within thepropellant chamber is Sub-sonic. Since the nozzle is theonly place the gas has to escape it passes thought theconverging section of the nozzle and it's velocity isincreased. This is because Subsonic gases acceleratewhen the area decreases.

As it passes thought the nozzle throat this gas is nowtraveling at Sonic speed.

Entering the second half of the nozzle the exhaust gas isnow Super-sonic and increasing velocity in thediverging section. Supersonic gases accelerate as thearea increases.

Diagram above of a de Laval nozzle, showingapproximate flow velocity (v), together with the effecton temperature (t) and pressure (p)


CONVERGING DIVERGING(SuperSonic)(Sub-Sonic)

M > 1Super Sonic

Flow

M < 1SubSonic

Flow

M = 1Sonic Flow

T

V

www.tclogger.com

DATA ACQUISITIONMade easy

Flight Thrust CurvesPropellant Characterization

Members of NASSA, Nevada AeroSpaceScience Associates have developed a solidData Acquisition System for testing propellants

Basic units starting at $300

Complete Systems just about virtually ready to go.

TRIPOLI GERLACH NEWSPAGE20

ANTIGRAVITY

REDNECKS & BRAILLE

WHYYAWNING IS CONTAGIOUS

CHINESE UNDERDEVELOPMENT

When a cat is dropped, it always lands on its feet, andwhen toast is dropped, it always lands with the butteredside facing down. It is proposed to strap buttered toast tothe back of a cat; the two will hover, spinning inchesabove the ground. With a giant buttered cat array, a high-speed monorail could easily link New York withChicago.

If an infinite number of rednecks riding in an infinitenumber of pickup trucks fire an infinite number ofshotgun rounds at an infinite number of highway signs,they will eventually produce all the worlds great literaryworks in Braille.

You yawn to equalize the pressure on your eardrums.This pressure change outside your eardrums unbalancesother people's ear pressures, so they must yawn to evenit out.

Communist China is technologically underdevelopedbecause they have no alphabet and therefore cannot use

acronyms to communicate ideas at a faster rate.

The earth may spin faster on its axis due todeforestation. Just as a figure skater's rate of spinincreases when the arms are brought in close to thebody, the cutting of tall trees may cause our planet tospin dangerously fast.

Birds take off at sunrise. On the opposite side of theworld, they are landing at sunset. This causes the earthto spin on its axis.

The reason hot-rod owners raise the backs of their carsis that it's easier to go faster when you're always goingdownhill.

The quantity of consonants in the English language isconstant. If omitted in one place, they turn up in another.When a Bostonian "pahks" his "cah," the lost r's migratesouthwest, causing a Texan to "warsh" his car and investin "erl wells."

EFFECTS OF DEFORESTATION

WHYTHE EARTH ROTATES

HOWTO MAKEYOUR CAR GO FASTER

THE CONSTANT CONSONANTTHEOREM

SIMPLE THINKING

AMBIHELICALHEXNUT

(3.1416 REQUIRED)

RECTABULAR EXCRUSIONBRACKET

TRICHOTOMETRIC INDICATORSUPPORT

0.0833 FT.

10.16 CM.

SOMETHING TO WORK ON IN YOUR SPARE TIME

JULY 2013

Date post:	24-Jun-2020
Category:	Documents
Upload:	others
View:	4 times
Download:	0 times

TRIPOLI PREFECTURE # 138rimworld.com/tripoligerlach/downloads/2013-03-04.pdf · 2013-07-05 · high...

Documents