Method for Heating Cast Iron for Welding

NOTV8 · Nov 17, 2012

and for giggles I glued this with my mig......

. It lasted a very long..........15 minutes :laughing::laughing: No preheat just grind a "V" and go :laughing: I know it's the wrong tool but.....

muddstopper · Nov 18, 2012

I like to lay the cast piece on top of the wood stove. Using a thermo heat gun the stove top is usually around 600deg with a fire going. Once the piece to be welded is the same temp as the stove top, I'' put on some coveralls to protect me from the heat and just weld the cast piece while laying on the stove. When I finish welding, I just leave the welded piece on top of the stove until the next morning. The stove will cool off as the fire dies down and the piece cools slowly at the same time. I have used brazing for the weld, but also nickel99 and nickle55.

I have an old antique fruit press that has a pretty large ushaped crack in it that I am going to try and repair. This piece was welded before I got it and had recracked the lenght of the weld. I have ground out the old weld and drilled a small hole at the end of the crack. On this piece, I dont want to use nickel or brass because of the difference in color of the weld material and the cast iorn. I will probably try welding with regular wire, which is what I think was used in the first attemp to weld the press. The difference will be I intend to pre/post heat the metal before and after welding. I have already attemped to use the Tig on a scrap piece, using another piece of cast as a filler but My tig skills aint that great. I dont know if it was my skills or something else, but the welded piece recracked, so I'll try the wire next. If that fails, it will be back to the nickel rods.

Stampeder · Nov 18, 2012

If you have a MIG then get yourself some Royal 44 from Crown Alloys.
It's designed specifically for welding cast iron without the need for heating, etc. Just stick it in your machine and weld according to their instructions. Lots of guys get excellent results without a lot of hassle or expensive nickel rods.

2 lb spool is $70.00 but worth it when you consider how easy it makes the job.

Glenn.

AKwelder · Nov 21, 2012

Heat it up and keep it at a minimum of 500 degrees, buy a "temp stick" (a crayon that melts at 500 degrees), weld it with 11018 or another high yield low hydrogen electrode.

To weld it run a bead on each side of the crack and then a third bead bridging the two, this seems to work best. an engineer ounce told me this helps to stop stress from the shrinking after the bead cools, but it does work

After you weld it make sure its hot again and wrap it in several layers of insulation (I use fiberglass batts you buy at the lumber yard) let it cool over a long period. When its done right the piece is still warm to the hand 24 hours later.

We use this method to repair cast steel bell cranks on large loaders and pieces that are cast on large yellow equipment, It works