Dale's Digger

Host Dale Schmidt

January 17th, 2004

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Dale Schmidt (host)Gilbert
Marty EscarcegaMesa
Doug WilsonPhoenix
Bob HarbourGilbert
Roger MatthesonLake Havasu
Tom DavisTempe
Andy DavisTempe
Owen JeffersPrescott
John CanonPhoenix
Glen LynchPeoria
Jeff LynchTempe
David ButterfieldPhoenix
Neil ButterfieldPhoenix
Ron WatkinMesa

Okay, here we go........
I purchased this car about 18 months ago from the estate of a friend who had passed away far too soon The original chassis was a 1968 Harold Wilson car built in Kansas. This design represented the state of the art in Top Fuel racing of the era.
It has since been through many engine combinations, and has been extensively modified in it's 36 year racing history. After running the car a few times I discovered major structural damage in the lower frame rails. I asked the NHRA tech inspector to assess the chassis, and it was quickly determined that extensive work would have to done to bring the car into compliance with the latest chassis updates required for chassis certification for the upcoming season. A new chassis that could still use all the components from the old car was the most cost effective solution to the dilemma. A quick search of the Internet,revealed chassis prices in the stratosphere! The materials were approx. 30% of the cost of the chassis, labor made up much of the replacement cost.
If I fabricated a chassis myself, I could customize the car to the drivers, (me) size and fit all the existing components like the steering box and front axle to the new car. A Miller Syncrowave 180 was purchased to do the tig welding required for the 4130 Cro-moly tubing used in the chassis construction. I purchased a chassis blueprint, and quickly determined the design was not suitable for what I wanted the new car to be. The new car would be of my own design, but heavily influenced by the 60's design of that era. In short, a blend of new technology and old school design! As a result, most of the parts used in the blueprint were not comparable with my plans.
To accomplish the fabrication, a few specialty tools had to be purchased and / or fabricated. A heavy duty hole saw type notcher was purchased from Pro-Tools to fit the tubing ends together for a minimum gap. 1 1/4" bender shoes for my shop built one shot style bender were also purchased from Pro-Tools.
This is a race car in the purest sense. In that fact, all of the drive line is solidly mounted, alignment of motor, trans and rear end is critical. An alignment bar had to be fabricated to pass through the engine main bearing bores and attach to the Currie 9" Ford rear end that was fabricated for this project. A new motor plate was fabricated from 1/4" T-6 aluminum plate to fit the new design. In the process of fabricating the motor plate, the shortcomings of my Chinese drill press came to light. A need for a higher degree of accuracy led to the purchase of a used DRO equipped Ex-cello milling machine. This machine has been invaluable during the construction of this project..
I began to research welding procedures for 4130 Cro-moly tubing and found that the filler rod used for this application is actually a mild steel rod. Several sources identified ER 80S-D2 as the preferred filler metal to use. A flex head tig torch and gas lens diffuser are also recommended for this type fabrication. Welding is done on DC straight polarity with a 2% thoriated tungsten electrode, 1/16" dia. ground to a point. Argon is used as the shielding gas.

Post meeting BBQ...