repair cam journal

Brian,
Just a side question, how do you tell that cam is steel?
If it's steel, I think the weld and grind is the way to go, one slug at a time, an let it cool to touch. It may still need straightening.
Perhaps use some U bolt type exhaust clamps over the journals, and clamping the cam down to w heavy length of angle iron. That should keep it as straighter than welding it unsupported. Talking three clamps, one for each journal.
Worth a think?
Martin.
 
Martin, The early motors ran steel cams, in 1935 they went to chilled iron and actually de-tuned them a bit. Easy way to identify them is they are fully machined [you can see where they've been turned between each cam lobe, whereas the cast ones have the cast appearance], also, hang the cam on end between thumb and forefinger, and give it a tap with say, a wrench, and it'll ring like a bell [tubular bells], indeed a beautiful ring. A cast iron cam will resound with a solid 'doonk'! yuk!!
 
Us old timers have done a lot things that we shouldn't of but go by with it. I had a 400 chev engine one time, the crank grinder ran the wheel right into the crank throw before he started the crank turning, looked like that cam with the flathead spot. I had a friend that was welder in a ship yard, don't now what he used for rod but welded it up and I had it reground, that engine went into a street rod and is still running. Walt
 
Brian,
Didn't realize they kept the steel ones to '35. Learnt something.
I got two or three cams in my pile that have that fully machined finish, I have wondered. If they maybe steel, I dismissed it back along as I thunk it was only '32 and these (I believe) arnt '32.
I'll dig um out and have a good listen.
Thank you.
As I said earlier, yours would be a weld and grind candidate.
Martin.
 
I would be very careful about clamping the cam to anything that is not a precision machined piece. The average piece of bar stock or angle iron is FAR from precise.

Again, I suggest the cam be carefully checked for concentricity and overall accuracy BEFORE any repair is initiated.
 
That makes perfect sence John, your right of course, angle iron ain't a good choice. Maybe precision matched V blocks on a lathe bed? This would be good to measure from before aswell?
Martin.
 
A good piece for aligning axles is the lover part of a metal press brake.
Good chunk of steel and usually 4 different sizes of ground V.
 
They successfully repair shafting by grinding undersize, flame spraying and grinding to size. There may be limits to how much can be built up but it might be something to look into. The lower temperature involved will negate any warpage, so maybe you could straighten, spray and grind. AKA flame spray, plasma spray, metallizing.
 
Would be looking for some money from the person who damaged that cam.

Possibly...but that would only be after an unsuccessful attempt to reclaim the camshaft. We'll try to fix the damage first.
 
Brian ,I think run it or weld but here is a Shade tree fix ?? ,You could possible get two cam bushes the size you need for that journal cut them through ,then create a dove tail in each and reassemble them over the small journal ,.Press them in with lock tight with a small amount of crush .Or even a v notched out matching the other ,it would take some precision filing .Maybe groove out the back and solder and reassemble .Ted
 
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Theres another way to save that cam which works perfectly I know from experiance repaired a damaged cam that so far has run well over 180MPH heres how it was repaired.
A while back the steel roller cam in my Land Speed Race motor experienced front and center journal damage due to oil delivery issues. I was able to save the cam by having industrial chrome plating placed on the damaged surfaces the journal was built up with material larger than the finished diameter.
Next the cam was center ground on a crank grinding machine which is a much better way of undercutting cam journals or in this case returning the journal diameter to the original dimension.
When I have a cam that measure's under Fords minimum journal diameter I use the crank grinder to do the undersize.
Of course the same could be done when the cam is being reprofiled by the cam grinder I had that done many times by Cam Tech whem Dave was still grinding cams. I still have a few L-100 cams ground .010 undersize by Dave in stock for future builds.
 
Ronnie, I thought of hard chrome, but wondered if hydrogen embrittlement would affect the cam. Good to know you've done this and given it a good test!! Thank you!
 
Hydrogen isnt much of a problem if its not things like springs.
If you plate clips and springs you give them a threatment after plating to prevent it.
 
Hard to see where the damage begins and ends. Looks to be less than 90* though. My opinion would be it will not be a problem. Obviously what I think isn't going to make you happy, and since the mistake is not yours, you deserve a fix that makes you comfortable.
 
There's not much I could tell Brian about motors but It looks like a groove on one side only ??I think like Russ you could run it but if its for a customer then you might need something better ,Hard chrome is pretty common to build up cranks so the hydrogen may be dealt with by bakeing .Ted
 
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One thing to remember the center grove of the cam allows oil to feed the crankshaft center main bearing and the four connecting rods for cylinders 2.3.6 and 7 theses rods receive oil from the crankshaft main bearing grove. The cam bearing journal must be round so there's no way oil will flow out reducing the oil flow to the crankshaft. There's a slight clearance between the cam bearing and the cam journal but anything over .003 would require a high flow oil pump to make up for the additional oil flow leaking leaking from a large amount of clearance.
 
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