I just welded my own cams today. Not something I recommend for everyone, But not the big bad monster that its been made out to be.
I dial indicated every camshaft and every sprocket face BEFORE AND AFTER I welded them.
I'd like to address the "welding warpage" issue. EVERY ONE of my camshafts wiggled the needle .001 or .002 while turning the engine. Sprocket faces had slightly more movement.
These things don't spin perfectly true to begin with. (outside of the journal surface on the bearing itself, maybe).
After welding ( I did a weld...let it cool. Do a weld... let it cool, etc.) I went back in and re-indicated everything. Nothing varied, at the most, 3/4 of 1000th of an inch. I blame me for the variance in not exactly locating the tool perfectly the same as the first time.
I also used an IR gun to monitor temps before and after welds. The heat from the tack welds dissipated surprisingly fast - just a few seconds after the weld and temps were below normal motor operating temps. Seemingly no opportunity for harm here. My shop temp was 51 F.
I used a .035 diameter wire and kept my amperage low to avoid distortion. Standard welding procedures.
I opted for 3 welds per sprocket and of course welded the shafts in the car. I believe the engine contact helps to rapidly cool the shafts to further prevent distortion.
Time will tell for sure but my dial indicators suggest that these shafts are plenty tough enough to take a little welding. I think pinning is an unnecessary over concern that some folks might be making a bunch of money off of. Arguably, pinning might be slightly better - but considering Fords' mastery of the concept of planned obsolescence - I believe that these welds will far outlive any car they are put into. (As the car is melted into pipe for making folding chairs "WOW there's nothing left working but these pins are perfect!!!")
97 Ebony SHO with 34000 miles
The wire is a Lincoln Welding product. NR - 211 -MP , their part # EDO16364. Its called an "Innershield wire" meaning it has a flux core. It produces its own gas so you don't need to use gas for clean, slag free welds. Kind of cool.
Anyway, it is 80% carbon steel, 10% iron, and the last 10% has more rare metals than I can remember.
Also, I practiced with different metals to test weld strength and adhesion. Dug into the box of broken tools. Stuck a cobalt drill bit to mild steel to a highly chromed deepwell socket to 300 and 400 series stainless steels and a couple of different high carbon tools as well to dial in my amperage and feed rate.
I was very pleased with the versatility of this wire and the consistency of the welds, regardless of which two dissimilar metals I was joining. Yep, got the hammer out too. These were more than just pretty welds. They were plenty strong to remove any concerns of letting go under my valve covers.
When I had my engine apart yesterday I noticed each camshaft had a HAND etched unique serial number on it. The numbers were etched on the shafts (looking down from the front of the car) between the first cam and second cams to the right of the sprocket. They were very faint and you kinda gotta hold your head just so to read them, but they were there. Have you seen these numbers before?
I haven't seen ANY references to serial numbers as of yet in these discussions. Maybe this could be a way of tracking a defective (or MORE defective) run of shafts which are most prone to failure. Has anyone tracked this info yet?
97 Ebony SHO with 34000 miles
97 self welded