Welding Tips and Tricks

need info on tig welding heavy cast iron
Heard form one source you could use aluminum bronze rod on AC?????
Bill Kydd

Hey mate,

Welcome to the group.
There is a dedicated stick welding thread down further. You will have more luck there. Also some info on tigging cast iron in the Tig thread. This thread is for istructions about using the forum. You can easily browse all the past posts. Feel free to copy and past and/or rewrite your post there. You can also upload pictures to help with your questions

Regards Mick

Hey, Mick,

Obviously, the topic was relocated. I'm posting to bump it back to the top for the OP.

Steve S

It depends on what you are trying to achieve. I have never used aluminum bronze on AC but I have silcon bronze on DC and it works great. Another options would be to use a nickle rod nickle 99, brute, and iconell 82 work very well. Those options work very well but are not the best on strength. If you are looking for strength er 70 s2 or s6 work but crack very easily, preheat and post heat are required. Post heat it the biggest thing on cast iron. You need to let the material cool in a slow control rate usually over three to four hours for really thick castings. I use a oxygen torch to add heat so it cools extremely slowly. With the silcon bronze and nickel 99, I have found you don't need a post heat as long as you don't heat up the part up to much while welding. That's what works for me. Cast iron is a crap shoot everytime you have to weld it.

I am interested in learning more about welding Cast Iron also. I have some new spindles on a Can am Commander side by side that I want to add straps around the tie rod and ball joint mounts to make them stronger. I tryed to mig a broken one and it does not take much of a hit with a hammer to knock it apart. The mig wire is your typical 70rs I believe..

I'm pretty sure those Can-Am parts are cast steel, rather than cast iron. More carbon than most forgings, and alloys all over the map due to recycled (no pun intended) content, but nowhere near the carbon content of cast iron.

The best Idea I've heard for welding cast anything, where preheat and slow cooling are critical, is to browse craigslist for a used ceramics kiln big enough to hold whatever you may need, say, a big-block V-8 exhaust manifold. You can preheat to brown-red, if you wish (too hot, but possible), and post-cool over 24 hours or more with the right timer.

I haven't tried this yet, as it's so rare that I deal with cast.

One other tip, courtesy of WerkSpace: Plain ol' dirt-cheap piston rings (not the chrome-moly types) are high-nickel steel suitable for TIG on cast filler metal, and can probably be had for free from a nearby engine shop.

Steve S

A nice low charcoal fire in the grill works great for post weld cooldown. S/F....Ken M

I tig using a rod MG200 on dc. you have to light up on the rod that's being held to the break and melt the rod onto the part. Never let the arc touch the base metal always keeping the arc on the rod to lay down a covering on the base metal then add rod to build up the area. You need to " v " out the crack and keep as clean as possible. The final weld is machineable without hard spots unless you arc to the cast which will pull in carbon and cause the weld to harden. You need to let it cool slow and you should be good to go. Only real down side is the rod is really expensive. You can save that motor that has a cracked motor mount from customers restoration with it and they are usually glad to pay the bill.