Macaulay's Molds (Patterns & Coreboxes) Part II

As promised, here is a follow up to my Tuesday post about the patterns discovered on a dusty shelf at the Macaulay Foundry as they were going out of business around 5 years ago. Miller, Offy, Novi and... <BR><BR>To read the rest of this blog entry from The Jalopy Journal, click here.

 

Well, time to start casting some offy motors.

 

That was truly an incredible find ! To have been there at the right time and seeing all that history being tossed away like that ! I still can't understand what they were thinking of as the owners or employees were just throwing away so much important racing history into a dumpster like that ! They are all one of a kind pieces of racing history that they could have donated to the racing museum or organization but instead they were throwing them out like yesterdays left over garbage !
I was very happy to hear that someone was there and was lucky enough to removed all that history from being thrown away and lost forever !
Do you know if he is ever going to do anything with the molds ? Does he know if he has any special molds of something really rare or what cars and racing teams they were for ? How many molds did he retrieve ?

Retro Jim

 

So Cool.. I want to see that stuff.. Amazing.. thank you for sharing

 

so...let me see...towers, cranks, cases, cam covers...some one needs to build a the CNC program to cut them out. i want 220 Miller/Offy T gow.

 

WOW, do you have an inventory of what he has the castings for?? I know some people who have small casting runs done for performance vw heads and blocks that might be a good resource to ask about doing these. would be cool to build one to actually race again too!

 

I totally agree just use a CMM to get all the coordinates into a computer, a little ProE or MasterCam work to produce a CNC program and you'd be off and running.

I know it'd be costly, but surely with all the aftermarket automotive manufacturing guys out there one of them would want to take it on.

 

These pictures make a bit more sense of it -- I'm assuming image 9 is used to make the cores.

Thanks for the pics, they are great!

 

That "mystery wooden crankshaft" could probably be identified if its dimensions were known.

 

Interesting article! Currently I have an Offenhauser 220 engine at Van Dyne's shop. The block was pressure-tested yesterday and tested OK. Offy 255 and 270 blocks have been reproduced but not the 220. We were discussing if it was cracked or unusable what could we do? The demand for a 220 is not as great as the 255/270 but this is a great find! Glad to know the pattern survived.

 

those old patterns are just to cooool

 

It looks like the wooden pattern for the crankshaft is for a V8. 90 degree throws.


Ago

 

Not as rare as you think! Some very cool old Schwinn tooling became ballast for the dock at the Schwinn families summer retreat in Wisconsin. Also, LOTS of rare Halibrand molds and patterns were chucked into a bonfire on the beach back in the 80s!

 

Again, a really nice thread and a fantastic inside track into a private world.
Thank you.

 

Does anyone know why they would cast a crank? Maybe to establish balancing factor or? Doesnt seem like an offy engine would live long with a cast crankshaft.
Steve

 

I had a 67 396 Chevelle with a cast iron crank and 4 speed and beat the hell out of it and never any problems. The Offy crank could be cast in steel too. Keep the pictures coming.

 

awesome stuff! thanks for sharing more photos.

 

That is pretty cool, those old mahogany patterns sure look different from today's standards. Those are truely a work of art to know those guys back then used mylars and templates to make these to dimensions and don't forget a shrink factor of probably .010-.013 thousands per inch.
If anyone has any questions about foundry process, reverse engineering, pattern building or CAD/CAM let me know. I have been in that game for a fair amount of time. I would be glad to lend a hand. COOL STUFF!!!!

 

Even the patterns for the engines are works of art; the craftsmanship that went into them was mirrored in the end product.......fats

 

Bob,
An individual on the East Coast recently found a Hilligass Sprint car [Miracle Power #1] that Tommy Hinnershitz [sp?] drove. Currently it is powered with a Flathead Ford. The car was originally built with a 220 Offy.

Finding a 220 is difficult since most if not all were built for sprint cars and last of that series was built around 1953-54. Offy 255/252/270 were used in Championship dirt cars and Indy cars up into the mid 60's.

The engine is in fairly decent shape but it will need insert bearings [current bearings are poured babbitt], pistons/rings, and a valve job [which is not an easy task, since the cylinders and head are one]. All internal parts will need to be checked for cracks and reuse.

To make one streetable, a starter/ring gear and flywheel must be made since the engines were made to be 'push started' or as with the larger engines a portable starter engaged in the front of engine was used. Ignition systems are fixed magneto, again requires work to make it 'streetable'. The fuel system is usually Hilborn mechanical injectors, again one can have the system flowed for gasoline or build an manifold and use side-draft carburators. Compression ratio must be lowered to run on pump gas which would require different pistons. Combustion chamber is 'pent-roof' design, similar to the Hemi. Many factors and time are involved but it can be done.

I know of at least three that are 'streetable'. Louie Senter's 27 T and Bob Anderson's A pickup and the 29 A on 32 rails roadster that my dad and I built. I believe Joe Gemsa built both engines for Senter and Anderson.

Thanks for your interest.
Offy 220

 

Steve,

Not sure why they would cast a crankshaft. When I saw the pic I thought the same. I have 2 spare Offy 220 crankshafts and determined that they were machined from billet. Common problem is that they crack at the fillet or radius, might be the reason for casting. I would believe a forging would definitely be stronger.

Offy 220

 

Dummies for mock up and test fit?

 

That is exactly what I was going to say. In fact when building my Harley chopper over 38 years ago I would make a part out of mahogany and quickly shape it into what I wanted then custom fit it then make it out of aluminum or steel. Saved a whole lot of time cutting wood 1st.
The shop was great & I miss having all the machines ready to go and all set up. Now I need to move piles and boxes to get to the machines.

 

The crankshaft pattern looks like it is for a V8, 90 degree crank throw. All the 4 cyl. motors Ive seen were 180 degree cranks or flat cranks. Some special V8 engines use 180 degree cranks. Ferrari 308,328,348,etc. Cosworth DFV,
The Offy was complicated to put the crank into . The barrel aluminum crankcase was heated to expand it, then the crank was lowered from the top. The main and rod bearings and caps were installed thru the crankcase windows. Briggs Cunningham tried to road race an offy on gas in the 50s with carbs. The ports were too big for good flat power curve.


Ago

 

Was at Van Dyne's shop this afternoon to inspect the Offy 220 engine. I mentioned to him about the cast crankshaft pattern. He said Meyer and Drake [Offenhauser] were trying different methods since they were getting cracks on the fillets and radius, typical with a billet crankshaft, and sometimes through the oil hole toward the fillet. He thought the cast crankshaft was not very common, most if not all use billet cranks.

Offy 220

 

They didn't live all that long with billet cranks. One of the commonest failure modes in an Offy was a broken crank. They would have been better off with forged cranks and possibly even cast cranks (assuming the casting was at least as good as the ones in Flathead Fords). Machining all that metal away when making a billet crank cut across all the grain structure of the billet leading to a mass of stress risers.

 

The way the tank crankshafts are done, at an old shop, is they are steel forged into shape quit close to the size then they are machined then heat treated to normalize the metallic structure, then ground to final size. This way all the stress factors are taken out.

 

Many of the Miller and Offenhauser drawings have been preserved and are available for study. Leo Goosen, engineer and draftsman for both, was a true artist.
Check out Gordon Elliiot White's books or Google either Miller or Offenhauser for links to the drawing archive.
A truly amazing heritage of engine design. Thanks to the guy who saved the patterns.

Chuck Schultz
Winfield, Illinois

 

WWW.harrymillerclub.com I`m sure someone there could find a use for them.

 

Looking at the pic's was really nice.I was a patternmaker for thirty years served my apprenticeship in wood and then went into metal. when ever i see a Detroit Diesel engine i look at the exhaust manifolds on them Another patternmaker and i made the original patterns and core boxes for them and i see they have not changed .