Is it feasible to metal spray a cam?

[Tom Goldman]

Bill, i'd look into grinding on a cast core.
Years ago when I first started building AMC engines ,I bought a bunch of parts from a circle track racer who was going to a BBC engine .
Amongst the parts were several cast cams that were reground into rollers.
I never had any wear issues with them and one is still in use today, 39 years later!
Lunati ground them ,and they were nitrided. Most hydraulic cams have a base circle around 1.300" , these were ground to a 1.150" base circle ,which gave plenty of meat to grind the flanks.

One note about metal spraying. I used to metal spray when I worked for General Electric.
Metal spray works very well in applications such as main bearing surfaces where the loading is constant ,and when the area to be sprayed can be undercut ,sprayed and then ground to size. Other surfaces we sprayed usually were not as durable.

[Chris Hill]

When I was at Eaton and we wanted to do the same thing, we actually tig welded the lobes instead of spray welded then grinded on it. I'm not sure what the rod was or the cam material. This was not converting from flat tappet to rollers though.

The camshaft was an old Ducati (sp?) and parts were not available and it did run afterwards, but not in a racing enviroment.

I may be mistaken, but I'm not aware of a spray metal weld that has ever been used in an actual strenght application like a camshaft. Most time I've heard of it used is to repair seal areas on shafts or to reman a turbine shroud housing.

[Greg Barsamian]

Associated Electro Mechanics (AEM)
185 Rowland St.
Springfield MA. 01107
(800) 288-4276
Welding, Metal Spraying, Plating and more
www.aemservices.com
e-mail: info@aemservices.com

[Tom Goldman]

Chris,thats similar to what the NASCAR Cup cars used to do to their cams.
They used welded inlays on the lobes to obtain a harder surface.

[Phillip marvetz]

Originally Posted by bill dedman

Well, Phillip, I called Comp Cams and talked to a tech there named "Buggy."

Here's what he said: " I don't know where Phillip got a roller cam for a /6, but we don't grind one. We have NO blanks for a /6 roller motor. If you send us a blank, maybe we could grind you one, but we have no source for a roller blank for that motor."

So, maybe somebody ELSE ground that iron roller cam for you????

Curious minds want to know....

The cam I have is for a 360 but it is a comp part#20-742-9, serial #ul1669-04, grind #crsxr274r-10. I talked to Tim Cole when I took it out of the box and saw it was not a billet core and he told me some of the street rollers were done this way. Based on this they should be able to grind you a cam from a standard iron blank. I know for a fact they have slant six cores because they have made me a couple for the stocker..

[bill dedman]

Originally Posted by Phillip marvetz

The cam I have is for a 360 but it is a comp part#20-742-9, serial #ul1669-04, grind #crsxr274r-10. I talked to Tim Cole when I took it out of the box and saw it was not a billet core and he told me some of the street rollers were done this way. Based on this they should be able to grind you a cam from a standard iron blank. I know for a fact they have slant six cores because they have made me a couple for the stocker..

Phillip, they have cores, but a roller requires a fatter lobr profile and apparently, there's just not sufficient material for the required lobe profile that would be needed for the roller.

At least, that's the way I understand it.

The slant six cores he has at Comp are for a flat tappet cam.

Am I wrong?

[Phillip marvetz]

Originally Posted by bill dedman

Phillip, they have cores, but a roller requires a fatter lobr profile and apparently, there's just not sufficient material for the required lobe profile that would be needed for the roller.

At least, that's the way I understand it.

The slant six cores he has at Comp are for a flat tappet cam.

"Am I wrong?"

Yes

[bill dedman]

I want to thank ALL you guys for all that good information. I'm not very hopeful that this is a good avenue to pursue, but I will nevertheless, pursue some of these good leads.

Thanks!!!!

[Grant Eldridge]

Bill, not sure if it applies in your motor, but on flat lifter chev BB the center of the lobe is offset a certain amount from the center of the lifter bore. That offset as well as the .002" taper of the lobe is required to make the lifters spin. Schuman in Iowa make a special lifter with a centered pointer for chev. to check this with marking compound on an installed cam. On a roller cam the lobes are apparently centered on the lifter bores so that the roller wheel is located in the center of the lobe, and the lobes are not tapered. Maybe it's not far enough off to cause problems in your application, but possibly worth checking out? I had thought about having a roller cam billet custom ground to my flat tappet stocker profile for strength but was told it would not work because of the lobes being located differently. Just what I was told.....
Grant

[bill dedman]

Originally Posted by Phillip marvetz

Yes

Can you elaborate?

I was told that by a tech at Comp whose name is "Buggy."

He was very specific that none of Comp's cores would work for a roller profile in a slant 6.

If I'm wrong, then he's wrong.

Where do I go from here?