Technical Camshaft Coatings Question

So I"m bangin away on the history of this Y Block roller camshaft and I am wondering what the copper colored coating might be ?

Please ignore the rust - thats not the coating I am referring to.

Any ideas? Cant ask the manufactor - long gone Harman & Collins

Oldmics

 

That is a steel billet cam. They copper plate the areas that are NOT to be case hardened.

 

Petel nailed it, front cover picture on a old Isky catalog with similar process....

 

I was going to say , remember copper turns that color. Pete is the winner.

 

Old -

As more of a complete answer...
The copper plate inhibits the full heat, during the heat treat process, from getting to the steel under under the copper plate. That way it stays a bit softer and not prone to breaking during the twisting cycles that a cam shaft goes thru.

Mike

 

I want to see the Y-block roller lifters....

 

Yeah, me to!!!!

 

There are a lot guys who want to see them. I'll add my name to the list.

 

As the old HAMB Metallurgist, the answer that the copper prevents the surface hardening is exactly right. Technically the process is called carburization; in simple terms it is adding (by diffusion) additional carbon into the steel surface. Extra carbon = higher hardness. The copper keeps the additional carbon from diffusing on the areas where the copper is plated.

 

The link below is about the cam.

https://www.jalopyjournal.com/forum...up-for-y-block-engines.1147279/#post-13047230

And here are the pics.

Yes,they really did exist. We also think we found the block this was installed into.

Oldmics

 

Yes, H&C. A friend had one in his sprint car. It won the regional championship one year.

On closer inspection of the above pic, I can see that is an H&C cam. It has inverted flanks on the lobes.
H&C were the first ones to do that commercially on hot rod grinds. They ground the lobes with an 8 inch diameter wheel to accomplish this. They were limited to the depth of the reverse curve (rate of lift) by the wheel diameter.
About a year before that we did some unlimited hydro cams by a similar method but used a 1.2" diameter contact wheel with an abrasive belt for a much higher rate of lift.
Today, cams of this type are common place and are done by CNC.

 

So were my comments correct in the other thread on how the lifters function and are held in alignment? AFAIK Chet Herbert was the first (before H&C) to use alignment bars on the lifters.

 

Yes.

 

I was wondering if the lifters had to be put in from the bottom of the valley or top as stock lifters are mushroom [to my knowledge] but looks like the assembly could be installed from the top side; after boring the lifter bores or not? The bronze "guides" maybe made up for lack of block material so boring bigger may work....Might those lifters be from a Harley-Davidson engine application of the time period? Great design/ingenuity, wonder what modern day cost would be...