Cast iron fireplace welding

[Mr J Morton]

Ive just bought a cast iron fireplace which needs slight attention. The worse of the damage is a crack on the left of the tiles nearest the fire basket on a 5cm wide section. Its not structural

The question is should I have a crack at welding/brazing it, or leave it as an authentic fire place with a crack denoting its age. Its not structural and I could make it worse and bring down the full wrath of the wife.

I used to arc and gas weld fairly well along time ago, but my new Cosmo has the usual symptoms which making it a less pleasurable exercise.

Jon

 

[breezer]

You'd need to braze with it being cast - weld will crack.

To stop the crack spreading you'd need to drill a hole at the end of the crack.

Personally I'd just leave it as it is unless it's structural / going to get worse.

 

[Archie]

With the right rods you'd be perfectly able to weld it up. There are several schools of thought on preheat/ no preheat but if it's just a small repair you'll most probably be fine without. Search for cast iron on the forum; there's been extensive discussion previously!

 

[Mr J Morton]

Thanks for the replies.

I wouldn't need to drill it as the crack is already right through. The part is only there to hold the tiles in place and is attached above and below the crack. I've read around the process of doing it (even watched an interesting video of a cut and shut Sherman tank welded with stainless steel), but having never brazed with a MIG and only welded with it once before, I'm not sure its a great idea, I should have kept the oxy acetylene set.

Having said all that I love to play and its sat there taunting me, and the Mrs is out late to night....very tempted.

I need talking out of it, is there anything else I could use to fill and or close the gap, about 1mm, I will have to black the whole fireplace anyway.

Thanks

Jon

 

[graffian]

A mate worked in the fireplace company that had a showroom in the kings road, all he did all day long was weld fireplaces back together. They had a huge stock of fireplaces and a lot were in jigsaw form. They were just wacked back together with a DC[murex tradesarc 130] arc and iron rods. I still have a box of the rods he used, the welds looked pretty ****e but they scurfed them off and polished the iron then zebrited them; you couldn't tell they had ever been damaged[unless you looked at the back]. Any missing bits they just welded in bits of mild steel sheet.

 

[Mr J Morton]

I restrained my self last night, from welding it. What kind of rods did he use graffian?

I no longer have my arc welder, so they wouldn't be much good to me at the moment but, I hope to get one when we next move to a place with a garage.

Jonny

 

[Archie]

Ah, sorry. I assumed you were planning to do this with a stick welder. If you haven't found it already Malcolm has a tutorial on welding cast iron with a MIG here.

 

[Omniata]

You can get some cheap MIG brazing wire off eBay too

Edit: MIG Brazing_Wire_Link

Here's the link, 1mm wire though...

 

[graffian]

Mig brazing sounds good, will zebrite cover the color change?

The rods used were universal welding alloys Cast 460.

If you want a couple I have a box of them.

It can't be difficult, when they had YTS lads that was the first job they gave them.