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custom
07-15-2008, 06:03 PM
i herd a few things of what could happen if you weld on cast iron 1. it wouldnt have a strong hold to metal... 2. it wont stick. is it possible for metal to be welded to cast iron with a wire welding machine?

Accordtheory
07-15-2008, 10:09 PM
Yeah, but it welds like shit. I've done it before a few times when I've had to, basically the iron vaporizes away, and if you increase the wirespeed/filler enough to fill it in, the iron likes to crack and pull away from the weld..and if it doesn't, it still doesn't have shit for strength, and will break easily. You're dealing with 2 different alloys/metals, basically the iron lacks other metals present in the steel, behaves considerably differently, and I don't know how you're going to find or use an alloy that has the same properties as the iron. That might very well exist, but I don't really know what it is.. (or care) I would prefer an alternative to welding the material, like replacing the part entirely or doing whatever else it took to get the problem solved..

cygnus x-1
07-16-2008, 06:00 AM
I've never done it but supposedly you can weld cast iron with a stick welder using nickel type rods. A wire welder will likely be pretty hopeless.

C|

carotman
07-16-2008, 09:08 AM
Read this:

http://www.mig-welding.co.uk/cast-iron.htm

This is THE website you need to read.

Ichiban
07-24-2008, 03:52 PM
We weld and machine cast all the time. Unfortunately, it fucking sucks. We've tried Arctec 50% alloy cast rod, Weldco 75% high nickel cast rod, and plain E7018 5/32. It actually seems like the 7018 rod machines off the best, but all of the rods have the common problem of the weld becoming extremely hard at the boundary between the original cast and the filler material. For simply joining the material, I'd say 7018 is sufficient, but we've yet to find a rod that really satisfactorily creates a machinable buildup. For example, I'd sooner drill oversize, tap and helicoil a stripped hole before attempting to build up, drill and tap in cast. Even if the drill lived, the tap surely wouldn't.

Also remember, proper pre and post heating is critical with cast welding. Count on preheating the part to at least 100 Celsius and insulating and post heating for another 2+ hours. At worst, failure to do this will shatter the casting, at best the weld will be glass hard.

Don't weld cast with MIG.



No!



Put the fucking MIG gun down.

Anyway, hope my experience helps somewhat.

lostforawhile
07-24-2008, 03:55 PM
We weld and machine cast all the time. Unfortunately, it fucking sucks. We've tried Arctec 50% alloy cast rod, Weldco 75% high nickel cast rod, and plain E7018 5/32. It actually seems like the 7018 rod machines off the best, but all of the rods have the common problem of the weld becoming extremely hard at the boundary between the original cast and the filler material. For simply joining the material, I'd say 7018 is sufficient, but we've yet to find a rod that really satisfactorily creates a machinable buildup. For example, I'd sooner drill oversize, tap and helicoil a stripped hole before attempting to build up, drill and tap in cast. Even if the drill lived, the tap surely wouldn't.

Also remember, proper pre and post heating is critical with cast welding. Count on preheating the part to at least 100 Celsius and insulating and post heating for another 2+ hours. At worst, failure to do this will shatter the casting, at best the weld will be glass hard.

Don't weld cast with MIG.



No!



Put the fucking MIG gun down.

Anyway, hope my experience helps somewhat.there is supposed to be some kind of new rod that works with a tig,but you still have to preheat, cast iron is a bitch to work with.

lostforawhile
07-24-2008, 03:57 PM
is welco still around? i have the old product guide,it lists what to use and how to weld specific items i'll look for you.i also have the antique audell welders quide there may be a forgotten old school trick to use, there are tips in there that guys i know who have been welding 30 years never knew.

Ichiban
07-24-2008, 04:10 PM
Wel(d?)co has an outlet down the road from our shop. They do all our bottles and consumables.

I just read the article on welding cast with stainless, and called my foreman and told him about it. We're going to try stainless MIG with low chromium, high nickel wire sometime soon here.

Bass Man
07-24-2008, 04:50 PM
I thought you had to AirArc it in order to weld it. Maybe that was just how they cut the old crap off.

custom
07-24-2008, 05:05 PM
YOU CAN WEILD CAST IRON GOT PICS TO PROVE IT!!! checkout my updates in before and after turbo in a minute

Ichiban
07-27-2008, 07:49 AM
YOU CAN WEILD CAST IRON GOT PICS TO PROVE IT!!! checkout my updates in before and after turbo in a minute

No shit. But can you weld cast iron and have it still machinable after? On an 11" diameter bore, we had to weld up about an inch of damage, and machine and blend it into the original material. Using a 4.5" boring bar with a lefthand 1" CNMG insert holder, and running at 33 RPM and .010"/rev, the cast rod weld material deflected that 4.5" bar over .100". It just about instantly destroyed the corner on the CNMG.

Not what I call machinable.