Welding Cast Iron

Date 10-20-2009 01:21

Welding cast iron is a crapshoot, sometimes it works OK, others it just doesn't.

Brazing is a more reliable repair on aplications where it can be used.

If You arc weld there are 2 completely different approaches.
1) short stringer beads with as little heat input as possible, naturally cooling between beads to where You can put Your hand on it
2) evenly preheat the entire part, keep hot while welding, post heat & slow cool

You might be able to hang the bell together and use it for decoration, but ringing it will cause it to break again, and it probably won't sound good either.

Is the stool worth the grief? If so, a brazed repair is probably Your best shot.

By up-ten

Date 10-20-2009 02:14

My nephew likes hammering metal for his knight armour and had found a cast iron shotput that he wanted to pound some metal on. He asked if I could weld it onto some sort of mount. I placed the shotput on a short piece of 3" square tube and heated it up to about 450F (checked with a tempstik) I welded it with 7018 but the first pass was pretty liquidy and pinholes were showing. I ground down that first pass to remove the pinholes and ran another pass of 5/32 7018 and that did the trick. Placed an insulated weld blanket on for the slow cool which surprisingly took about an hour and a half before I took the blanket off. The nephew says its holding up fine and I guess I won the toss in that crapshoot. Bob.

By ronnie taylor (**)

Date 10-20-2009 02:32

could you use a high preheat, weld with nickel, peening between welds an cooling in sand?

By DaveBoyer (*****)

Date 10-21-2009 01:18

I would use wood ashes, vermiculite, fiberglass house insulation, Kayowool & etc for insulation. Sand doesn't insulate all that well.

By FixaLinc (****)

Date 10-21-2009 04:31

I just used sand because it's what I had but the rest of what Dave is saying is lots better.

By Superflux (****)

Date 10-21-2009 04:52

Kitty Litter, best bang for the buck for "annealing medium". Or a barrel of the industrial floor dry.

By FixaLinc (****)

Date 10-21-2009 23:29

Never tried absorbent stuff for that but I would sure read the label or MSDS before using it around any heat. Reason I say that is last time I got some oil absorbent at wally world the bag said to avoid contact of the absorbent product with some solvents and acids could cause a flammable condition. I thought that was nuts and won't buy it there again. First time I ever heard of that. We have always carried oil soak in fire trucks to use at wrecks on streets but why some of it would be flammable ? So read the label first.

By FixaLinc (****)

Date 10-21-2009 23:30

By Superflux (****)

Date 10-21-2009 23:56

Did they specify which solvents and/or acids, combinations there-of? If not...Sounds to me more like the "Legal Eagles'" all inclusive coverage umbrella. Since they have no control over what their product is exposed to once it leaves their shipping docks.

Just remember how dangerous "Di-hydrogen oxide" can be!

Good advice and reminder though, always read the instructions and MSDS.

"I am a Non-attorney Spokesperson" for the Law Offices of Do-we, Cheat'em and How.

By FixaLinc (****)

Date 10-22-2009 01:19

The product itself is not considered flammable but it could be once it absorbs something but we should all know that right. It was a incompatibility issue I was shocked to see on the label and MSDS.

Page 4, Oil Dri MSDS

Incompatibility: Physical contact between this material and turpentine, hydrofluoric acid, vegetable oil or other unsaturated organic compounds (such as fish oil) may generate heat and / or fire. Do not use this material with these compounds.

Scoop on the poop.

http://www.oildri.com/indusauto/pdf/MSDSGranAbs08.pdf

http://www.fundinguniverse.com/company-histories/OilDri-Corporation-of-America-Company-History.html

Apparently others have the same issue too. Just first time I ever saw or read that earlier this year on a sack of oil dri.

Incompatibility page 2:

http://www.sharecorp.com/msds/1803OilAbsorbent.pdf

Another one:

http://www.imperialinc.com/msds0052350.shtml

Makes it sound like cats should be wearing a respirator mask ? lol

By Superflux (****)

Date 10-22-2009 01:49

It's not my kitty I'm worried about. It's the dogs that are cleaning out the cat's box that are facing the inhalation risks. NEVER let them lick your face!!!

Why do dogs lick themselves..cuz they can!

Why do cats lick themselves..cuz they taste delicious.

By FixaLinc (****)

Date 10-22-2009 02:03

ROFLMAO :)

By phaux

Date 10-20-2009 03:03

Silicon bronze, tig, amazing stuff

By Akwelder Date 10-20-2009 04:02

my boss says u can weld anything with silicon bronze but i would try some ni 99 or ni 55 ive got a roll of .045 ni 55 maybe ill try some cast some day

By Tommyjoking (****)

Date 10-20-2009 05:59

oxy acet WELDING with Iron rods made for the purpose is the way to go ......but its very much a "lost" or black magic kinda art. I have tried it under the eyes of a man who could do it well.....umm I had a real hard time with it. Here is a website with some product and technique info.   http://www.cut-like-plasma.com/info_welding_cast_iron.htm   This would be the best way provided you and your base materials are up to it.

I have had good luck ( i do mean luck).   With different Ni rods using the preheat and hold the temp method on larger cast pieces. You need to have a squid/air scalier handy for peening the weld as you go. Skip the welds around and do not concentrate them in one area.   A lot of times having a buddy handy with the rosebud is a good idea on a large part.   Make sure everywhere you will weld is clean as possible and you do not have a lot of variance in gap width. In fact having a large gap or a lot of fill area will just about guarantee failure inmho. The problem with this is it can be an expensive repair if you need lots of rod+gas for heating....and if it goes wrong    crack!!= wasted effort and money. After finishing that last peen it needs to get buried in sand completely within 10 minutes or so and just left alone till its ambient temp.

The silicon bronze is the most sure fire way to go. You can do it with your OXY ACET or with a TIG (it will smoke like heck) But remember you are brazing with it not welding, don't melt the iron. It will hold and will not crack out from different rates of contraction like Ni will with ease.

Good luck to you.   Like Dave said....sometimes its really a crapshoot. But arm yourself with information and you much improve your odds of success!

Tommy

By DaveBoyer (*****)

Date 10-21-2009 01:25

The guy who demonstrates the Henrob torch says cast iron piston rings work well for filler, I havn't tried it yet.

Part of what makes cast iron such a crapshoot is that there are several grades of "iron" used in casting, and an unlimeted variation in quality among them. Some can be welded like steel, others can't. It is pretty hard to know what You are working with 'till You try.

By FixaLinc (****)

Date 10-20-2009 06:08

If older quality cast maybe. Foreign cheap mix cast made today just figure you are practicing on it for experience and might not work at all. If still has more stress cracks spreading out drill small holes part way or all the way through at the end of those cracks to keep them from spreading more. Brazing like Dave said probably best thing to try. Nickel rod isn't cheap nor works well on thin cast. Square cast iron rod isn't cheap either and need some of that red brick colored flux for it from Harris but works the best on thick or thin cast. I don't have a shop oven but have used a BBQ grill to heat manifolds then welded and peened weld and buried in wheelbarrow of damp sand. One works fine and then the next one cracks again just never know. This guy George makes cast repair look easy ? :)

http://www.georgemillermachine.com/

By dash Date 10-20-2009 21:10

Thank you all for your posts I have always valued this forum for the knowledge and help that I recieve. I will try the methods that all of you have mentioned I have some exp with oxy welding and brazing.

By 803056

Date 10-20-2009 21:44

Oxy-acetylene welding has my vote. Use the cast iron rods that are actually cast iron. Preheat the entire part. I've used the oven in the kitchen, didn't get any for a week after that little stunt, but the weld works just fine. I've also used a 50 pound bag of charcoal to preheat a large casting and a second bag to ensure the completed weld cooled nice and slowly. That piece was for a large printing press that is still in operation after being repaired some twenty years ago.

Good luck. You might consider reading the recommended practice for welding cast iron available through AWS. I have a copy of it here somewhere, but it isn't at my finger tips so I can't give you the actual title.

Best regards - Al

By Tommyjoking (****)

Date 10-21-2009 06:53

Al when time is not such a valuable commodity (sic).

Maybe you could give me some in person pointers with the iron rods some fine day. I was young and much less experienced when I tried it...like I said I did not do well or really feel comfortable with it. This fella I worked with was always having people bring him "irreplaceable" pieces/valuable antiques and he would pull out this technique and charge handsomely for it. I have always wanted to get this into my bag of tricks..actually be good at it....but time and opportunity being what they are I have never had the chance to go back and really learn to do it well. But I know if you really need it restored and need as close to original strength as possible..its the only way to get there.

Tommy

By FixaLinc (****)

Date 10-21-2009 23:41

Tommy, If you get some of those cast iron sticks try the 800 Harris flux with them it's kind of brick red color. I've just used them with a torch. One guy local here tells me he uses those cast rods with heli arc but I've never seen how well that works for them or tried it that way. Link to some Harris fluxes.

http://www.harrisproductsgroup.com/flux_chart.htm

By Superflux (****)

Date 10-22-2009 01:40

I used to have the dubious honor of repairing cracked castings on machinery bases and pedestals with the OAW process using the square cast iron rods with 20 mule team borax for flux. The man who instructed me was in his 60's at the time and had first made these type repairs at that plant back in the 1930's. He was of course in supervision in another department, gave me the quick rundown on it and left me to my own devices.
These were up to several inches in depth and several feet in length. I would have 2 helpers with rosebuds keeping each side of the entire zone glowing red, while I used a blowpipe with a pencil sized orifice. Aside from heat, heat and more heat, the trick I had been taught was to literally stir the molten puddle with the square rod and basically let the heat of the molten metal consume the filler rod. This was to physically aggitate the puddle so nodules of carbon did not migrate into clumps. The typical Oxy Acetylene Welding of steel is "dripped" in.
This bell repair will be a slow and arduous task by this method, but I think if it were done properly with appropriate PWHT, it could even retain its tonal qualities... a different sound, but better than nickel welded, brazed or silicon bronzed.
Just fly me out to your shop, provide the beer and chips. I'll assist you for free...

Hope this helps,
John
Oh yeah, if you go this route, be sure to use full face protection or your nose and lips will fall off within 2 days.

By FixaLinc (****)

Date 10-22-2009 02:00

Thanks John great info ! I got to remember that for flux now because I had H*** with LWS last time getting them to only order me 2 or 3 cans.

By Superflux (****)

Date 10-22-2009 02:11

Sometimes, you're just not going to improve on archaic technology. Othertimes minimally so. Water for the drill press (blow it off wipe it dry and spray it down with oil/WD40 afterwards). Think of all the rage with serrated knife blades these days, a throwback from the flint knapped edge???

By DaveBoyer (*****)

Date 10-22-2009 03:12

20 Mule Team Borax is sold as a laundry additive. The box is just short of 5# and costs about $6-7. Some say You can use Boraxo hand soap, there is borax in it. I KNOW 20 Mule team Borax will work, it is pure borax.

Boric Acid [roach powder] should work too.

By Superflux (****)

Date 10-22-2009 03:44

" I KNOW 20 Mule team Borax will work." This is ALL I have ever used. Anyone that wishes to experiment with other products such as the ones Mr. Boyer mentioned...I'd like to know the results.
The 20 Mule Team stuff is getting harder to find than "strike anywhere" matches. Last box I bought came from an Albertson's Supermarket which is a division of Osco Drug Stores.

According to the Blacksmithing literature, they say for forge welding you're supposed to melt it, cool it then pulverize into fine powder. This removes the water from it I'm assuming it is hydrated so it will dissolve in the washing machine. For OAW and Brazing, this is not necessary. Heat up your rods, then dip into borax. Torch on dude!

And YES! Use it in your laundry for improved results...whiter whites and brighter brights!

By DaveBoyer (*****)

Date 10-23-2009 02:31

I know a handfull of people making forgewelding flux for sale, they are mostly mixtures of borax or boric acid and iron oxide. If feldspar is used, it is to keep the borax where it belongs. There are some more agressive fluxes being used for pattern welding chrome containing alloys, but You sure wouldn't need those for gas welding cast iron.

Borax absorbs water naturally, even if You go through the grief of drying it [heat & pulvarize several times, 'till it no longer clumps up] unless kept in an airtight container, it becomes hydrated after a while.

I forget where I got My borax, but I think it was the local supermarket, about 4 years ago.

By FixaLinc (****)

Date 10-22-2009 22:52

Yep knew what the borax stuff was and like Superflux said probably can't find it in a store now but I'll be looking next trip. Know the dollar stores have boric acid in 1 lb. containers cheap. You can get medical grade boric acid at drug stores too it's used for washing out the eyes when diluted with water. Most LWS got a minimum order on those square cast rods unless can find one that stocks them. Still got some found at a auction.

By DaveBoyer (*****)

Date 10-23-2009 02:35

I have some of the cast rods too, but they are really big, 3/8" square or more. The Henrob rep says cast iron piston rings work just as well. There must be a bunch of them amongst the stuff in My shop's basment, but it would be easier to beg some from an automotive machine shop than find Mine.

By Superflux (****)

Date 10-23-2009 06:56

Hey Dash!!!,

Where's my plane ticket??

I wanna fix that Bell and Ring It!!

If it breaks...I'll pay ya back for the beer...OK???

By Superflux (****)

Date 10-23-2009 07:01

FixaLinc,

Thats why they call me Superflux...

If I caint weld it "FLUX IT"!!!!!!!!

I am curious about those piston rings though....rather intrigued............

By Tommyjoking (****)

Date 10-23-2009 08:04

I LOVE IT

FixaLinc, Copy on that bro, I was using two cans and it was hard for me to keep up. Had to keep adding and adding ...ugghhh!!

Superflux thats what I am talking about....to do it correctly it takes some technique (that there ain't very many people around to teach). You also got to get the right set of goggles or lenses in to see what the hell your doing because you really got to see. It is not like brazing or cutting at all. Its hot and time consuming. One of these days when I retire, I will mess around with it till I am comfortable enough to do someones 32 ford starter housing or what have you....beer money.

LOL I knew if I brought it up ...some people would come out of the woodwork. I am very surprised Dave did not mention it first (potential can of worms in advice eh Dave?).

"sometimes you are not gonna improve on archaic technology" Yep in this case I believe that's 100%

Best regards fellas
Tommy

By FixaLinc (****)

Date 10-23-2009 20:42

Yeah for what Harris flux costs it doesn't last long. George in Maryland got me to using that stuff though now going to try the borax.

By DaveBoyer (*****)

Date 10-24-2009 04:15

Tommy, I am reluctant to suggest something I havn't tried Myself. I learned to braze rom My Grandpop, who was a machinist. He was good at brazing, used it for everything. I don't think He knew how to weld or not well, gas or electric.

My flux suggestions are based on what works for forge welding, pretty close to the same temp range, and too hot for most brazing fluxes.

I brazed up some fairly thick cast parts, cast iron to mild steel. The largest was the steadyrest for His 16" lathe. It was from some other machine, so We added steel and machined it to fit His.

My success rate brazing cast iron has been better than My luck rate with stick welding it.

By FixaLinc (****)

Date 10-23-2009 20:43

It's Batman to the rescue, NO it's Flux MAN ... NO it's SUPERFLUX ! :)

By FixaLinc (****)

Date 10-23-2009 20:35

Rods I have are 1/4 square or 3/16 ? Never tried pistons rings either but wondering about the oil in them. Guess you just heat it out with torch then flux and weld. I've thrown away lots of 3/16 or 1/4 wide rings from old big bore 2 cylinder John Deere engines 5 1/2 to 6 3/4" and big MM engines should have saved if that works good. Get some rings from a big oil field engine rebuilder those would be plenty big enough.

By DaveBoyer (*****)

Date 10-24-2009 04:17

Do You want to swap a few # of Your smaller rods for a few# of My bigger ones?

By FixaLinc (****)

Date 10-25-2009 04:05

If you want rusty ones? Dang looked today and they had rust on them and some of the nickle rods had flux falling off. Teach me to store them better. :(

By DaveBoyer (*****)

Date 10-26-2009 01:34

How badly are they rusted? I guess they would be fine after a sandblasting, might even be OK with a wire brushing. I need to look at My own, I don't think they have deteriated since I got them, but they might be a little rusty too, as the surplus yard they came from was careless about storage.

Yes, I would like to swap several pounds.

By FixaLinc (****)

Date 10-26-2009 04:57

I'll have to look. Forgot was going to try bead blasting some to try this weekend. Got a little project was going to try them on and see if they still work. Send me a PM or email and I'll let you know.

By DaveBoyer (*****)

Date 10-27-2009 02:06

PM sent.

By Len Andersen (***)

Date 10-29-2009 17:08

Fellow AWS'ers,
   Welding Cast Iron is covered in AWS “D11.2-89(R2006), Guide for Welding Iron Casting” and ASTM A488. The repair use of welding for cast iron was carried out on a tool post and two gears of my 1916 about Monarch lath about 25 years ago. Using the availability of New York City. There were two shops specializing in the work. One was run by a world glass expert that the US Government flew to Arabia on such matter and as a fellow engineer was hell of man to speak did a braze job on the gear. His way of making money diesel engine cylinder heads nickel rod and peening. They were in on pallets and out on pallets. The shop might employed twenty. The other shop might have employed five and was the only welding shop with a "furnace" out of a blacksmith cowboy movie I seen in a shop. Put the tool post near the flame and preheated about 500, put the weld on it and put it back near the flame backing it off maybe having a plus two-hour cool down. The second gear drilled, tapped bolts cut off top, and filed in the shape.
   Our society has good people to talk to at 305-443-9353, 305-443-7559 FAX. Last time I cast called I spoke
Ed F. Michelle Metallurgist with a Casting Background Ext 254 and Anthony Y. Oseitutu Ext 314. Chair guess is you could buy three with repair cost of less than a guarantee and the bell, a furnace job and start talking in the hundreds without guarantee. Casting iron castings I have worked on with current work were 12 x 12 x 5 feet and were reported to be over 100 years old!
Sincerely
Len Andersen
   914-237-7689 / 914-536-7101 / 212-839-6599
   POB 1529 / NYC 10116 ( $990 per year Caller Box GPO NYC )
   www.lenandersen.com
   PS –   http://lenandersen.com/personal_info/resume.html
Leonard Morgensen Andersen
Construction Project Manager
New York City Department of Transportation (NYCDOT)
Division of Bridges
55 Water Street – 5 th Floor WS-05-3F
New York, New York 10041
landersen@dot.nyc.gov

212-839-6599 / FAX 4042 / Administrative Assistant 4012