Brake drums-are they weldable?

[digger2]

jwmorris,

thanks,i checked it out and there it was,on the chart-Brake Drums.....
gray cast iron.I'm sure there are a few exceptions,but i took a close look at mine and i'm pretty sure they are cast iron.I'll come up with a different
way.
thanks to all who replied...digger2

 

[Renze]

I've seen lots of toplink brackets that were cast steel, vs cast iron.

I assume you're right about it being cast steel, as they even made their wheel weights of cast steel instead of cast iron... I know someone who uses them as low ground pressure pads bolted under support legs of a MF 60 backhoe

Would brake drums be steel or iron ?

 

[RedDirt]

I had a welder friend that worked in a cast iron repair shop. I broke the cast iron top of my wife's wood cook stove. He showed my the correct technique. This was years ago but I remember a few things.

1. Like previous post, prep, prep...very clean.
2. Preheat (with a torch) as much of the weld area as possible and as far out as possible. Small item would be entirely preheated. Not super hot but a bit too hot to touch with your hand.
3. Back-step your weld. ie. weld one inch length, skip one inch, start your next bead and weld back into your first bead.
4. Peen - As soon as the slag hardens (at each step weld) take a ball-peen hammer and make one sharp blow on the middle of the weld crown. This sends a needed shock wave through the "new" metal and heated native metal. There was something about this process aligning the molecules is a certain direction. The "new" metal is the combination of the native metal with the added nickle rod. Like a ripple from a pebble thrown in water the shock wave aligns the new metal and native heated metal molecules while the metals are still hot.
5. Slooooow cool. We had asbestos in those days and would wrap the whole piece several hours until it was back to room temperature.

The shock-wave item is weird and maybe some will say bunk. I just know this guy was already big pipe certified (Alaska pipeline) and a NASA certified welder (read exotic metals). I met him in college while he was getting a metallurgy degree, and I distinctly remember him emphasizing the peen technique although some of my reasoning my be a bit off.

By the way, the stove cook top lasted fine with daily use for almost 15 years...then it was stolen.

 

[Soundguy]

Would brake drums be steel or iron ?

I don't know enough about your setup to say.. hopefully someone else can answer that for you... Many drums I see I -believe- are CI.. though have no evidence to back that up.. etc..

Soundguy

 

[xlr82v2]

RedDirt,

You're remembering correctly. Peening is a very necessary step in welding cast iron. It relieves stresses in the metal that would otherwise cause the weld to crack as it cools. And the slower you can cool the part the better, for the same reasons.

 

[Renze]

I slowed down the cooling process of the top link bracket by grinding the welds smooth afterwards. The heat of grinding put some heat back in, to slow down the cooling.

About hitting it with a hammer during cooling, would that just work with small objects, (read: objects that you could normally deform with a hammer) or also on thick solid steel pieces ?

 

[RedDirt]

I slowed down the cooling process of the top link bracket by grinding the welds smooth afterwards. The heat of grinding put some heat back in, to slow down the cooling.

About hitting it with a hammer during cooling, would that just work with small objects, (read: objects that you could normally deform with a hammer) or also on thick solid steel pieces ?

Another way to "slow cool" is to toss the piece in a bon fire, maybe cover it with clean dry sand, then let the whole batch cool naturally. The shop my friend worked at had a huge oven. They'd place several whole engine blocks and larger stuff in it. They also kept several bins of sand in the oven and they could place smaller object in the sand, take out of the oven and let the mass cool.

As I recall the peening process is suitable (required) for both small and large pieces. The metal should be cool enough so that it does not deform. This is usually when the slag hardens. Then each individual step weld gets one sharp whack on the crown of the bead. If the weld is inaccessible to a hammer, like the inside of an "L", use a pin punch.

The pieces I have welded have been relatively thin (1/8" - 1/4") and the piece would cool down to quickly before the one foot +/- bead was completed (one inch back-stepped / peen process). We'd light up the torch every few minutes and pre-heat in front and post-heat behind until the full length was done then slow cool the entire piece. If there were several cracks in different locations needing repair each one was done individually. eg. pre-heat, weld, slow cool (the whole piece) for one crack then pre-heat weld, slow cool (the whole piece) for the next crack, and so on. It is a slow process.

 

[Harry c]

Unless I have some compelling reason to weld, I usually Braze cast iron. It's really quite easy, fast and far less particular than welding. Use brass rod, the right flux and a good OA torch and you'll be surprised how well it will hold.

 

[Soundguy]

Steel and CI also silver solder well.. just like brass.. easy and less hassle.. if the temp range and strength meets your needs.. etc.

soundguy

 

[workinallthetime]

You could just bend a hook on the all-thread and let the cement hold em.Weld up a cage out of some re-bar before you pour for added strength.
I stopped by the local tire shop looking for some old wheel weights.The guy told me he was getting 68 cents a pound outta them....back to the concrete.Carrying on a war sure gets expensive.

funny you should say that, we just went up on our rotate and balance price from 39.95 to 42.95 because of the price of wheel weights. if the sweat shops would quit using all the lead up in childrens toys the price might go down.