"No-PreHeat" Cast Iron Repair Technique

[ChuckE2009]

Goodafternoon, everyone!!

So, this is the latest of my Cast Iron welding videos... I repaired a "crack" in a transmission housing without any kind of a preheat, or a post-heat:

Basically, Cast Iron cracks when it's heated and/or cooled rapidly, hence the reason why its usually pre-heated and allowed to cool slowly, but theres a chance that you can get around this by just not getting it very hot...

I used a Nickel-99 electrode to make welds under 1" in length, which I then peened and allowed to cool completely, so that I could run my fingers directly over the weld, at which point I ran another short weld using the "back-stepping" technique, and repeated...

This is a technique that can be used with any of the main electric arc welding processes... I've seen it done with TIG using stainless filler, and I've heard of people having success with it running MIG , again with stainless filler...

Its just a little technique that I heard of, and had to try, I made a video about it and just thought i'd share... Doesnt seem like a bad way to weld a cracked engine block or something along those lines...

Well, hope you guys like the video... Have a great week, everyone!!

 

[kevin37b]

Chuck you do a nice job . Where did you get the ventilator ?

 

[ChuckE2009]

Thank you!! Its an AVANI unit, I really like it

 

[creekbend]

Thanks for posting.

 

[yomax4]

Most Cast is done now days with little or no pre heat and small stitch welds peened as you go. In many cases it is better to use a synthetic nickel instead of the 55-99 etc. there are several synthetic Ni rods that will work when the regular Ni rods wont. Check them out under the name Nickel Free Electrodes. MG has a couple as does Harris Welco. Other than that their are several Premium Ni rods out there that were the origional German recipe and cost more. See MG 289, Welco 65 or 94..All listed do better with minimal preheat. Spray Powder is still my favorite and I use it 1st if possible. You don't have to Blast the work with a bunch of Amperage and only need to get it burgandy red..Less chance of cracks.

 

[Tractor Seabee]

I have used an Eutectic arc product that is a bronze/copper alloy with out preheating. You need to drill a 1/4 hole at each end of the crack so it doesn't spread past the weld. Depending on base metal thickness you need to bevel the joints and fill up level +. Again like nickel, step weld and keep the base metal temp down. It is not a fusion process, more of a brazing process. I have also bronze welded cast with O/A but you need to pre-heat as that is a hot process. That process also works for joining non-ferrous to ferrous base materials. We did a lot of copper or brass to steel that way.
Ron