which rod for welding mild steel to cast iron

[ranchersam]

which rod for welding mild steel to cast iron?

[Aerometalworker]

which rod for welding mild steel to cast iron?

Technically there is no good way to perform a fusion weld between the 2. However Bronze brazing has been done for years with great results,i.e. rear axle assemblies. Maybe some more detail on what your working on would help.

[Rocky D]

You could use silicon bronze with TIG or brass braze with O/A. There are occaissions where a weld on the steel part will capture a cast iron part, and while they may look welded, they usually crack apart, after awhile.

[Spud83]

I worked for a fab shop for about 3 years and the only rods we used were nickel. Very costly but they work great on cast. e.g. welding cracks in exhaust manifolds. preheat and postheat is used to stop or minimize cracking. I have seen people braze cast but it always seemed to take alot of prep to get it to work. Good luck with your project.

[FusionKing]

I have used 309 for this and had good results many times.:D Pre-heat and post heat and peening all used.:cool: YMMV

[ranchersam]

I was also thinking of nickel rod with preheat and postheat. I am making a quick and dirty cultipacker that runs behind my grain drill, about 7 in. spacing. I'm running a 1 3/4 pipe through 1 3/4 hole coulter wheels. I'm putting spacers/bushings to separate to the right distance so each wheel runs behind a seed drop. The pipe is mild steel and has a bearing on each end that allows the pipe to rotate. The wheels are cast. I just didn't want to have any extra friction and noise with the wheels running on the pipe. So I just wanted to tack the wheels to the pipe so the only turning part is the pipe. I bought some rods from tractor supply or northern tool ( don't remember which at the moment), I think it was $10 a lb.

[Big Rig]

I am also very interested in this. i have to section a set of spindles for our show car so we can fit bigger wheels on it. even though the car is mainly used for show, we still drive it a bit from time to time and usually go for a cruise after the show.

I need to extend them 1 inch or so. i have pics of another guy doin it but i cannot contact him for reference. he had made a 3 sided sleeve that cupped the spindle and then it looks like a tig weld to hold it all together.

now, if this was your car and you had to put your family in it....how would you weld it?

[84ZMike]

now, if this was your car and you had to put your family in it....how would you weld it?

I wouldn't....I would pay for the correct part or have it made....welding CI to mild is a failure waiting to happen.....if it was art or something to set on my desk as a paper weight then I'd use 7018....simply for the look it would produce....

[Sparkeee24]

Howdy Howdy!

there are several correct ways to make this work, depending upon the installation and use. I can't comment on the TIG method myself. For the original farm machinery question, I think I would grind a couple notches, small ones, like 1/8" deep on each side, kinda like splines where the cast piece slides over the steel shaft. then I would weld to the steel, and fill in the gap that I had ground into the casting with steel weld. I would not be surprised if it were to crack, but the function would work just fine. Even cracked, the steel nubs within the ground slot would hold for the life of the tool. I'm suggesting do the same as truck axle manufacturers do with cast iron differentials, and there plug welds to hold the steel tubing into the casting. I would not try to drill the casting in your case though, I would just grind notches on either side of the hole in several places and use those to lock it into place. Easy and fully functional.

As for the show car, I wouldn't. What spindles are you referring too? The spindles I am familiar with are splined drive shaft spindles, or inner / outer half shafts. There are no cast iron parts on these that I'm aware of. Cast Iron to Steel fabrication should include a means to mechanically hold the two pieces together if / when a crack occurs. You should not for instance put a cast iron part flush on a steel part, and weld it together and expect it to hold in automotive use. I have done this with spring perches with no problems, using the high nickel rods, temp sticks with pre and post heat, and lots of peening with a needle scaler. Then the whole thing is held together with leaf spring U bolts, so even if something breaks, it's still all held together solidly.

I do like the high nickel rods also. Nickel 55 and nickel 99. It is more of a "butter" rod, not really at all a digging rod. The price has tripled in 2 years also. Brazing has been used for a LONG time and works well also, and is great for agricultural use. One of the hardest things to do, is to get the cast iron clean, as it is soooo porous, it both soaks in, and continually spits out "funk" while heated. I HIGHLY recomend getting a temperature paint stick for preheat and postheat. They're cheep, like 5$. they are a paste, like chalky crayon, and only melt at a very certain temperature. You can get them in many temp ranges. It REALLY helped me get it dialed in for preheat. The cast pieces I've worked with used WAY WAY WAY more heat then I thought it would for pre heat. The stuff really soaks up the heat. I know with the brazing, that the proper flux really really helps too.

Good luck! Brian Lee Sparkeee29

[irrnceltic]

I work in a fabricating shop in NKCMO. we recently welded cast iron ballisters and end knoules on the mild steel tubing we used for the rail body. i'll find out the aws number of the rod we used and post it tommrrw. the welds were fairly strong but not real pretty and we had to let completly cool before moving (usually overnight).