Enjoyed watching and looks great. I wouldn’t have thought of taking out the side of threaded section of the hole. But understand this must be to get the weld to the bottom of the damaged hole.
In the process of doing this to a pair of 1966 1300 heads. I've competed the welding. Cut the area out similar to yours. Heads were chemically cleaned but still had a heavy oxide layer to remove on the surface. I rarely tig weld castings, always surprised at the contamination that Can come to the surface that's freshly cut with a carbide burr and cleaned with acetone. I used 4047 10% silicone filler. I haven't set them up in the mill yet to do the machining . No cracks in my heads but exhaust guides are flogged out. I think they are untouched from the factory - car was last registered in 1987. I'm building a 1510cc engine with some NOS Kolbenshmitt 83.5mm 0.5mm oversize pistons, ported heads and a baby cam as a vintage performance engine. Also trying repair rather than throw away parts you can't buy any more. Thanks for your videos, John.
Awesome! I'll have to look into that 4047. I know some people use 5051 and other say it can be brittle so I've always stayed with the 4043. It seems like all I have been doing lately is castings. I think it's fun to try and sculpt them back to original looking. These are pretty rough so I didn't get too carried away.
Both 4043 and 4047 are mentioned in the Berg tech articles. 4043 with 5% silicon should give a more ductile deposit for say thinner areas like a port wall. The 10% silicon of 4047 gives better machineability for tapping a thread or surface milling like a gasket face - higher strength but less flexible. If you are building up an area you could use both rods as you progress, matching the specific characteristics of the filler to each area.
Enjoyed watching and looks great. I wouldn’t have thought of taking out the side of threaded section of the hole. But understand this must be to get the weld to the bottom of the damaged hole.
In the process of doing this to a pair of 1966 1300 heads. I've competed the welding. Cut the area out similar to yours. Heads were chemically cleaned but still had a heavy oxide layer to remove on the surface. I rarely tig weld castings, always surprised at the contamination that Can come to the surface that's freshly cut with a carbide burr and cleaned with acetone. I used 4047 10% silicone filler. I haven't set them up in the mill yet to do the machining . No cracks in my heads but exhaust guides are flogged out. I think they are untouched from the factory - car was last registered in 1987. I'm building a 1510cc engine with some NOS Kolbenshmitt 83.5mm 0.5mm oversize pistons, ported heads and a baby cam as a vintage performance engine.
Also trying repair rather than throw away parts you can't buy any more. Thanks for your videos, John.
Awesome! I'll have to look into that 4047. I know some people use 5051 and other say it can be brittle so I've always stayed with the 4043. It seems like all I have been doing lately is castings. I think it's fun to try and sculpt them back to original looking. These are pretty rough so I didn't get too carried away.
Both 4043 and 4047 are mentioned in the Berg tech articles. 4043 with 5% silicon should give a more ductile deposit for say thinner areas like a port wall. The 10% silicon of 4047 gives better machineability for tapping a thread or surface milling like a gasket face - higher strength but less flexible. If you are building up an area you could use both rods as you progress, matching the specific characteristics of the filler to each area.