Is that a topslide or cross slide way? If it was a topslide I was going to advise you to look for a new one as they might be easy to find. In fact a lot of guys are replacing the topslide (compound for us in NA) with a solid block to make the machine more rigid. But a cross slide is a different matter. Welding cast iron is tough because with the high carbon content it is brittle and can't take any internal thermal gradient without cracking. So as the previous poster mentioned, you can't heat up one area and have the adjacent areas still cold - it will suck the heat from the weld and also the internal stresses will cause a crack for sure. So you have to heat the whole thing up in say a bbq, insulate it with blankets, weld it, then cool it down gradually. There are newer nickel based welding rods that can weld the material quite well. And you can braze it. And some guys weld it with directly with a torch, flux and filler metal from cast iron piston rings (Kent White for one - but he is not your average welder). Then they put the part in a wood stuff with some logs and let it burn down over 24 hrs or back in the bbq and let it all cool gradually. But for an enco Chinese lathe you have to wonder if it is worth it. Try to get a replacement part if you can.There is a crack in back of the top slide and the way is bent. Should I try and braze this back together? The rest of the lathe is in pretty good condition.
Sharpie line to show crack.
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