Pouring Camshaft Bearings Thrust Surface

[Harry Lillo]

I plan to re-babbitt some camshaft bearings for my next projects. I have a nice jig to pour the babbitt and tool to create a nice round OD on the cast halves.
Now I have ran out of stock on bearing halves that are long enough to satifsy the overall length (end thrust) requirements.
For the next batch I will need to create the new thrust surface on the end of the bearing. My pouring jig is capable of adding the babbitt to the end of the castings
What experience do others have in doing so?
Do you drill anchor holes in the castings?
Is there a minimum thickness for the babbitt thrust surface?
Would I be better off brazing a new thrust surface?
I would like to hear other's experiences?
Harry

[TXGOAT2]

If the surface behind the babbit is well-tinned, the babbit layer can be very thin.

[Harry Lillo]

Pat, I believe the cam bearings are cast iron.
I have not had particularily good experiences with tinning cast iron.
Please let me know what you have found?
Harry

[TXGOAT2]

It can be done. I have not done it. Many old radiators had cast iron inlet and outlet fittings soldered to the brass or copper tanks. That required tinning the cast iron. Tinning is also required on babbited forged steel rods, bearing caps, and cast iron main bearing caps. I'd think brass would work fine, but it would require more heat than tinning and babbiting.

[speedytinc]

I plan to re-babbitt some camshaft bearings for my next projects. I have a nice jig to pour the babbitt and tool to create a nice round OD on the cast halves.
Now I have ran out of stock on bearing halves that are long enough to satifsy the overall length (end thrust) requirements.
For the next batch I will need to create the new thrust surface on the end of the bearing. My pouring jig is capable of adding the babbitt to the end of the castings
What experience do others have in doing so?
Do you drill anchor holes in the castings?
Is there a minimum thickness for the babbitt thrust surface?
Would I be better off brazing a new thrust surface?
I would like to hear other's experiences?
Harry

How are you taking an old cam beating & machining the OD?. The 2 halfs wont mate/lock again. If you are filling that lock area with babbit, that makes for a bearing that will loosen. The thrust surface is iron. Babbit wont work here with the forces exerted. If you are doing what I think, you are wasting time & effort to produce a poor quality, short lived part.
Your best method is to make a new shell with fresh iron & split as originally done. Babbit is not necessary. Early T cam bearings had no babbit & were higher H/P motors. When decent bearings were not available, this is what I did. The high cost & questionable quality of replacement bearings makes this a feasible/worthwhile project. Contact me with a # if you want to discuss.

[Dan Hatch]

How about just rebabbitt the id and use a cam thrust kit to control the thrust?
Like with a regrind cam? Dan

[speedytinc]

How about just rebabbitt the id and use a cam thrust kit to control the thrust?
Like with a regrind cam? Dan

IF the split still locks tight & IF the OD is still good, that's an option.
The bearing halfs can be tin plated. Not sure if that would damage the split fit, but that would add some to the OD and a base for the babbit to stick.

[BobShirleyAtlantaTx]

. Bob 903-824-1949