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This is the cast iron piece in question. It's the top baffle to a Jotul wood heater. I plan on heating it up to maybe 300 or so in my electric range or propane grill, check heat first with infra-red non contact thermometer, and then attempting a weld with nickle rod. I probably won't need to grind out a V in the crack because I already have a sort of V there with one part having moved up above the other. I'll drill a hole at the end of the crack. Let cool in a five gallon bucket full of wood ashes. There's another smaller crack just forming at the opposite side of this baffle. Probably just drill that one at the crack end and see what happens later. If it fails, I'll at least learn something. I ain't no pro, just a backyard welder.
Reply:I think you should inquire about a new part. It looks burnt to me and if it is no one will make a satisfactory weld on it.---Meltedmetal
Reply:Your chances for laying down a good bead will greatly improve if you shine up that weld zone with a grinder. If welding doesn't work, you could braze it.
Reply:Originally Posted by grumpycricketYour chances for laying down a good bead will greatly improve if you shine up that weld zone with a grinder. If welding doesn't work, you could braze it.
Reply:I suppose it is worth the effort for the learning experience. If you have any good clean scrap cast iron around, break it and weld it to see the difference. I've made temporary repairs on stuff that burned up by bolting a steel patch over the break (away from the fire) to hold some fire cement or plastic fire brick if there is room. Operative word "temporary".I don't hold out much hope for success on your stove part but good luck with it all the same.PS-I'm not criticizing your procedure, I just don't think you have much to work with in that piece.Last edited by Meltedmetal; 04-18-2016 at 06:26 PM.---Meltedmetal
Reply:Was that piece flat when new ??? If it's just a flat top baffle I would consider making a new one with some steel plate. You should be able to buy lots of plate for $168.00.
Reply:Originally Posted by BD1Was that piece flat when new ??? If it's just a flat top baffle I would consider making a new one with some steel plate. You should be able to buy lots of plate for $168.00.
Reply:Its cooked, so your outcome percentages are against you for starters. If it was me, I'd break it in two before trying to weld it.
Reply:Muggyweld makes a rod for burnt cast iron. I've never used it bit they seem to be the only ones who even try.Eventual master of the obvious, practitioner of "stream of consciousness fabrication". P.S. I edit almost every post because because I'm posting from my phone and my fingers sometimes move faster than my brain.
Reply:Remember that there are extreme differences in the quality of cast irons. Some will weld so fine and others, well, not so much. Also know that your first pass will probably be riddles with little pin holes. That is impurities coming out of the cast. Just grind the weld almost all the way out and make another pass. It may take several passes before you see a good weld. Only make 1" welds and beat the flux off. If you weld too much at a time then you are liable to have it crack on you.I've had very good results for over 30 years with the UTP 85FN rods for dirty cast iron but they have gotten up to $88 a pound. Good luck.
Reply:CharleyhorseInterferon: is the only 'Electrode' that will save a Liver afflicted with this degree of Cirrhosis.Opus
Reply:Damned if you ain't a big help
Reply:Check out www.LockNStitch.comThey have a nice section on welding cast iron.I would preheat to higher temperature, if you are able.This will reduce the thermal differential stress that causes the weld to crack.DonSmith Oxyacetylene TorchMiller Dynasty 200DXLincoln SP-250 MIG WelderClausing/Coldchester 15" Lathe16" DuAll Saw15" Drill Press7" x 9" Swivel Head Horizontal Band Saw20 Ton Arbor Press BridgeportLincoln LE 31 MP & Lincoln 210 MP
Reply:If I was heating it in the oven or grill, I would put it back in there to cool by lowering the temperature every half hour till I got down to 150 or so, then turn it off.
Reply:Originally Posted by Don52Check out www.LockNStitch.comThey have a nice section on welding cast iron.I would preheat to higher temperature, if you are able.This will reduce the thermal differential stress that causes the weld to crack.Don
Reply:Typical oven will go to 500 deg F, maybe a bit higher. Gas grill might be a bit cooler because it probably isn't as well insulated as the stove is..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by SedanmanMuggyweld makes a rod for burnt cast iron. I've never used it bit they seem to be the only ones who even try.
Reply:Originally Posted by Charleyhorse but I'm getting discouraged about minimum welding preheat temps being at 500 degrees. I'd probably need an oxy acetylene torch to get those temps.
Reply:Originally Posted by BobRemember that there are extreme differences in the quality of cast irons. Some will weld so fine and others, well, not so much. Also know that your first pass will probably be riddles with little pin holes. That is impurities coming out of the cast. Just grind the weld almost all the way out and make another pass. It may take several passes before you see a good weld. Only make 1" welds and beat the flux off. If you weld too much at a time then you are liable to have it crack on you.I've had very good results for over 30 years with the UTP 85FN rods for dirty cast iron but they have gotten up to $88 a pound. Good luck.
Reply:Originally Posted by DSWSounds like a good reason to buy yourself a nice gas forge! There are ways you could build a rough gas forge to get something like this hot enough, but I don't think it would be cost effective vs just buying the piece you need. 500 deg is nothing in a gas forge. Iron/steel doesn't start to show color until you are up around 1000-1100 deg F or so. A simple coal forge would also probably work, but you might end up with contaminants on the surface if your coal isn't fully coked and burning well. All you really need for a "coal forge" is a hole in the ground, a piece of pipe to funnel air into the hole and a blower of some sort, say a hair dryer. Infrared thermometers are fairly inexpensive now days. You could always stick a medium sized piece of steel in your oven and set it on high and see just how hot it gets after an hour or so. I know my gas oven has a setting for 500 deg, but I can't remember if it goes to 550 or not off the top of my head.
Reply:My area Air Gas will break boxes to a pound. Probably wouldn't do it on the web though. Check your local one if there is one. The whole reason I use them is the no pre and post heat part. I do a lot of pump castings with them but it is better quality cast iron so to buy them for this is a chance no doubt.
Reply:I have a house oven in my shop for heating parts. It goes to 550f.12v battery, jumper cables, and a 6013.I only have a facebook page. https://www.facebook.com/pages/VPT/244788508917829
Reply:Your fist lesson on welding cast iron is pick your battles. The piece is not worth fixing. Next is sometimes brazing is best, sometimes welding is ok. In general thin cast iron brazing is the only choice. Heavier cast iron welding works and brazing works. Burnt cast is almost always not worth dealing with. I have done both but I prefer brazing. I will say that when a piece of cast comes in to my shop I tell the owner that it is time consuming and is not cheap. Most parts are not worth what it will cost to fix. I repaired an H frame from a backhoe yesterday that seemed like it was cast iron but I think it was semisteel. I repairs it like it was cast iron. It took me 2 1/2 hrs to repair and I used at least a pound of ni-rod. So that repair was about $200 and no guarantee. I told him I could build a new piece out of steel for about $450. He wanted it fast ( not good for cast iron) I pushed it a little more than I would have if it was full cast iron. If it had been full cast iron that repair would have taken at least twice as long and would still not be as good as new. The price would have been close to what the new one would be and I know the new one would hold up. The piece he brought in had been fixed twice before and I told him it will break again , just a matter of when. The metal was a very poor choice for what the part needed to do. I told him if it were mine I would build a new piece out of steel.Last edited by thegary; 04-19-2016 at 06:28 PM.
Reply:Originally Posted by BobMy area Air Gas will break boxes to a pound. Probably wouldn't do it on the web though. Check your local one if there is one. The whole reason I use them is the no pre and post heat part. I do a lot of pump castings with them but it is better quality cast iron so to buy them for this is a chance no doubt.
Reply:Originally Posted by Charleyhorse but build a new baffle anyway out of steel plate so I have a backup piece if my cast iron repair fails.CharleyhorseInterferon: is the only 'Electrode' that will save a Liver afflicted with this degree of Cirrhosis.Attachment 1402931You can repost - but you cannot hide . . .It's akin to a cheap piece of meat - the more you chew it - the bigger it gets . . .http://weldingweb.com/vbb/showthread.php...ighlight=JotulOpus
Reply:Originally Posted by John TSteel plate / I would be concerned with it warping.... as far as preheating the cast piece... Is it possible to heat it with actual wood stove itself? build a fire... take it out and weld it. ?I had a similar piece for the bottom of my coal/wood stove..... long story short.. I bought a replacement piece. (cast iron)
Reply:Originally Posted by MeltedmetalI suppose it is worth the effort for the learning experience. If you have any good clean scrap cast iron around, break it and weld it to see the difference. I've made temporary repairs on stuff that burned up by bolting a steel patch over the break (away from the fire) to hold some fire cement or plastic fire brick if there is room. Operative word "temporary".I don't hold out much hope for success on your stove part but good luck with it all the same.PS-I'm not criticizing your procedure, I just don't think you have much to work with in that piece.
Reply:If you end up buying a new cast-iron piece,There is also a procedure for breaking it in. Basically a bunch of small fires Before you really get it hot. So they say...Sent from my iPhone using TapatalkMiller 211Hypertherm PM 451961 Lincoln Idealarc 250HTP 221 True Wisdom only comes from Pain.
Reply:Originally Posted by CharleyhorseI just took a closer look at this piece of cast iron after cleaning it a bit, and the entire surface of the thing is a honeycomb of cracks. The entire piece is in the process of fragmenting apart into tiny chunks sort of like a piece of safety glass does when you hit it with a hammer. Now I understand what "burnt" cast iron is. Time for it to go to the recycle pile and back to a foundry. It's toast indeed.
Reply:My gas grill will go to 800 degrees real easy! I sear steaks at 500 degrees all the time.
Reply:http://weldingweb.com/vbb/showthread.php...anything-thickInteresting thread. Forhire gets a braze done using only MAPP!
Reply:I say go ahead and v it out and run an inch of ni rod and see what happens.
Reply:^ yup, 50% of cast is weldable, don't know unless you try it.12v battery, jumper cables, and a 6013.I only have a facebook page. https://www.facebook.com/pages/VPT/244788508917829
Reply:Don't V it out. Cast iron will do much better with less chance of cracking with a U groove.
Reply:Pretty much all been covered on this thread. Glad to hear you are scrapping it. I was going to tell you to please do so. Just because we can weld parts doesn't mean it's always a good idea. It's part of your wood stove and as someone who heats 95% of their family igloo with wood for the better part of 9 months out of the year... Remember that all wood stoves need maintenance in that they CONSUME parts, more so when they are overfired. You DON'T want the fire getting out of the box! House fires are no fun, and I've seen way too many happen even when the stoves are maintained.Even when welding the cast is a good idea, unless you know the quality of the cast (as in past history fixing the same type of part) it can be a 50/50 shot at best. I would advise against heating the parts in the oven, ESPECIALLY if Mrs. Weldor is home. The grill is a way better and SAFER option and gets MUCH hotter anyway. You can get those cast parts to 750-800F easily and no need to worry about burning up your oven and house if there is oil or grease on the part. Step one is to grill some burgers while heating up the grill, then grill yer parts while eating the burger, when you're done, throw it back in the grill to reheat and cool SLOOOOOW. If the cast welding doesn't turn out too well, at least you got a burger out of the ordeal.RyanMiller Multimatic 200 tig/spool gun/wireless remoteMillermatic 350P, Bernard/XR Python gunsMiller Dynasty 350, Coolmate 3.5 & wireless remoteCK WF1 TIG wire feederMiller Spectrum 375 XtremeOptrel e684Miller Digital EliteMiller Weld-Mask
Reply:VPT Originally Posted by VPT^ yup, 50% of cast is weldable, don't know unless you try it.
Reply:Originally Posted by OPUS FERROThan - and only then - do you proceed. The identity of the iron dictates - procedure and rod selection . . .Anyone that advocates welding cast iron - with any 300 series stainless rod - hasn't done any critical cast iron welding.
Reply:xryan Originally Posted by xryanJust like the the other cast iron thread about engine manifold repair when 2 commentors balked when I said NOT to use 309. "Well bla bla bla I used it and it worked." (eyeroll)
Reply:Originally Posted by OPUS FERROI can't respond to . . . .Opus
Reply:I welded cast with 308l. It does work but like Opus mentioned nothing critical.However I have been impressed with its strength on the couple parts I welded on my shear. I welded one foot back on and one of the hinge sockets for the foot stomp part and they have been holding up great to my abuse.12v battery, jumper cables, and a 6013.I only have a facebook page. https://www.facebook.com/pages/VPT/244788508917829 |
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发表于 2021-8-31 22:08:40