Temple of Triumph Meeting MinutesSeptember 8, 1999

The meeting was called to order at 8:16p.m.

Treasurer's Report:

The Temple bank balance is $1,401.43.

Old Business:

The idea of the Temple hosting next year's VTRRegional was discussed, TomRush reported that thedowntown venue looks good. We will need a firmcommitment from the hotel, and a street-level areafor the concourse.. probablyAdams Street,closed offfor the event..

For those planning to attend the VTR Regional inLake City next month who have not yet received aregistration form in the mail, check the web site atwww:freenet.tlh.f1. us/ -tcnf/registration.

The annual TallahasseeScottishHigWandGamesandCeltic Festival will be held sometime in October. The

event will probablybe held at Falls Chase onBuck LakeRoad, with a possible English Autocross in the fields.

New Business:

Joe Carter suggested a road trip to Calloway Gar-dens, perhaps in January. This would be two-day trip.

Our annual Beach Party was discussed. This willlikelybe held in mid to late November at JK and Chris'sbeach house.

The meeting was adjourned at 9:11p.m.

Calendar of Events

British Car Classic Mark XIOctober 23, 1999Jacksonville, FL

Hosted by MG Classics ofJacksonville Car Club

Details: Chris Waage, (904)285-4998

Southeastern Region VTROctober 27 -October 31, 1999

Lake City, FLDetails: Art Kelly (904) 446-9990

Tallahassee Scottish Highland GamesTallahassee, October 30, 1999

For details, call Gordon McLeary(850) 622-3000 #210

HSR Vintage Sports Car RacesNovember 5-7, 1999 Daytona Tnt.Speedway

For Details OTtickets, (904) 253-RACE

2 Wlft Wtmplt Wabitt @rtnbtr, 1999

"~hy Not a SolidRollbar?

By Andy Prevelig

That is a question I've asked myself. Afterall, a solid rod would be easier to bend with-out the liability of crimping or kinking, andeveryone knows that something solid has morestrength than something hollow.. right? Theanswer might surprise you.

The S.C.C.A. had no data on the relative

strengthcomparisonsbetweentubingand solidrod, since nobody had ever brought up theidea. I found the answer by writing toautox@team.net.

Of the severalresponsesI got, the one fromMark Sipe at TeamZ3below really gave theanswer:

"Stress comparison of both solid and tu-bular circular sections of constant radius is afunction of the section modulus ofeachmem-

ber, and a direct relationship can be obtainedby equaling the diameter relationship func-tions between the solid and tubular sections

(there is a constant that is equal in both equa-tions and it cancels out):

tubular relationship = {(OD)4th power - (ID)4th power}/OD

solid relationship = (OD)3rd power

"~-~~--"---'

Setting the tubular and solid relationshipequal to each other, and knowing that the tubu-lar diameters are outer dia = 1.5 in and inner

dia = 1.25 in (1/8" wall thk) we can solve theequivalent diameter for a solid member:

solid OD = [{(tubular OD)4th power - (tubular ID)4th power}/(OD)]1/3rdpower

solid OD = [{(1.5)4th power - (l.25)4th power}/(1.5)]0333power

solid OD = I "20 inches

and the weight relationship between the twocan be based on equivalent area, which is a func-tion of (diameter) 2nd power. You will quicklysee that the solid member is 2090/0heavier, giventhe same density material.

However, if you want to evaluate the solid andtubular members based on deflection, the cor-respondiIlg comparison is a function of themoment of inertia equation, and setting themequal creates a similar situation with a slightlydifferent formula:

tubular relationship = (OD)4th power - (ID)4th powersolid relationship = (OD)4th power

solid OD = {(1.5)4th power - (L25)4th power} 0.25 powersolid OD = 1.27 inch (234% heavier)

It should now be clear why tubular membersare used; they're considerably lighter for a givendesign load. The difference in the two sizevariations demonstrates that the tubular mem-

ber handles deflection slightly better than stresscompared to an equivalent solid member. "

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Automotive Voltage Stabilizers

Mechanical Stabilizer

by Roger Garnet

The "Voltage" Stabilizer as found in the fuel, tem-perature and other gauge circuits of many older auto-mobiles is really a type of current regulator. They area mechanical device, usingcontacts on "bi-metallic"arms, similar to a turn signal flasher. This regulationserves two purposes- reduces gauge flucuation dueto battery & charging voltage changes, and averagesthe response of gauges, to avoid transient readings,such as gas tank sloshing, etc.

The bi-metallic arms are made from strips of twocar-e-fullyselected, dissimilar metals, laminated to'gether. When heated, the two metals expand at dif-ferent rates, which makes the arm bend in the direc-tion ofthe metal which expands the least.

When cool, the contacts are closed, and electric-ity flows. This current flow through the arms gener-ates enough heat warm the bi-metal arms, and theybend away from each other, thus breaking the circuit(and stopping the generationof heat). Once the metalcools, the contacts close, and the cycle begins again.By changing the material and size of the metals, aduty cycle (on & off time) can be established, basedon expected current draw in the circuit.

A standard signal flasher maycycle very fast whenthe extra lights of a trailer are connected.This is over-come by substituting a "Heavy Duty" flasher.

""'I

As these stablizers were common in many carsthrough the 70's, even if an exact replacement foryourcar is not available, you may be able to find a goodsubstitute from your local parts store or salvageyard.The modem alternative is to replace it with an elec-tronic version.

Electronic Stabilizer

From the TR3-TR4A Bently Manual:

"The voltage stabilizer is a small sealed unit, located underthe facia on the right hand side of the car, and is used toprovide a constant current [sic] of 10 volts for the operationof the fuel contents gauge and the temperature indicator."

What I saw, looking at the output of the stabilizerwith an oscilloscope, with the battery fully charged(12.6Vat 50degreesF)and the engineoff,wasa squarewave swinging from 0 volts to -12 volts (positive"earth" you know), with a frequency varying widelyfrom about 3 Hz to less than 1Hz. The duty cycle wasa bit more consistent at just under 50%. This wouldcorrespond to, not surprisingly, an average voltagevalue of right around 6 volts.

To double check this, I built a low frequency"aver-aging" filter out of a 10,000 uF capacitor and a 1 kohm resistor (which gives a time constant similar tothat of the gauges), and measured the filtered output,whichwas 5.9volts,closeto the value estimatedabove.

The fuel and temperature gauges in my TR4 are ac-curate and stable, so I assume that the 10 volts men-tioned in the Bently is incorrect, and that the value of6volts is the correct value, at least for my car.

So, for those of you that have considered making a"stabilizer"outof moremodem components,it appearsthat an LM7906 3-terminal regulator, with a 10uF orso capacitor at the output, and a IN400 1 diode in se-ries with the input from the battery to block opposite-polarity transients, would make a suitable substitute.

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4 ~4t ~tmplt aJahltt (!!)rtnbtt,1999

Classified AdsAd~ are free to members and $15.00 for non-members (in-cludesmembership).NOTE: Ads will runfor six monthsandthen be deleted unless you contact the editor to renew them.

Wanted: SCCA-approved roll bar to fit Triumph Spitfire.Must be reasonably priced. Call Andy at (850) 878-6460 orE-mail toaprev@tdo.infi.net.

Moving Sale: Two visiblegas pumps: 1920-30, one restored- $1,495.00, one unrestored - $850.00. Parts washer, neverused - $75.00. Engine stand - $75.00. Ramps - $8.00. Creeper- $5.00. MIG welder, new, in box - price negotiable. CallCharles G. Smith at (770) 518-8659

For Sale: 1977MGB. 84,000 miles. Runs good, needs little.Call Terry Hughes at (850) 566-4007

For Sale: 1975 MGB (rubber bumper) in good shape. Newtires, paint, top. $2,500. Call Jody Miller at (850) 562-7472.

For Sale: 1958 TR-3 for restoration. No rust above floors.Price reflects new parts purchased. $2,500. Call TommyAdams evenings at (912) 377-6307.

FREE: MGB-18GB engineblock w/internals. No head. Con-dition of crank, etc. unknown. May make great anchor! Free.Call Obin Hamrick (850) 878-8453.

For Sale: 1971 TR-6. Red wlblack top. Overdrive. Goodcondition, needs minor interior work. Asking $5,400. CallChris Tober (850) 656-8576.

For Sale: 1977 MGB roadster. Red. Top and interior okay.Does not run.Asking $500.00. Call David Humphreys (850) 222-8622.

For Sale: 1976 TR-6. Immaculate paintjob. Interior assem-bly needed. Engine needs work. Great restoration project.$3,500.00. Call Jeff (850) 681-3993.

For Sale: 1977 Spitfire. Red. Fair body. Runs good. Needsclutch pressure plate. $500.00. Call Brandon Ashby (850)577-0454.

AUTO - CROSS

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I

By Rachel Baker

1 6 72 3

8

ACROSS DOWN

1 Parkinglight(Brit) ,

8 April 15th agency9 Prefix meaning air

10 Zodiac sign11 Spanish Mrs. (abbrev)12 Suffix meaning doctrine14 Article or French tea15 Noncom officer (abbrev)18 Classic auto20 Rock group21 Military entertainment group22 Turn into an automaton

1 Muffler (Brit)2 Anger'3 Medal4 Countershaft (Brit)5 Fuel6 That girl7 Tie-rod (Brit)

12 Clara Bow has this13 I name I call myself16 Arafat's group17 High shot in tennis18 Uncle's child (slang)19 Peer Gynt's mother

answers to last

months puzzle

wIle wemple wahlet (IDrtnher, 1999 5