Hmmmmm.... Does that make you a crusty 60 year old out back?
Any what are you out front?
-
Scam Alert. Members are reminded to NOT send money to buy anything. Don't buy things remote and have it shipped - go get it yourself, pay in person, and take your equipment with you. Scammers have burned people on this forum. Urgency, secrecy, excuses, selling for friend, newish members, FUD, are RED FLAGS. A video conference call is not adequate assurance. Face to face interactions are required. Please report suspicions to the forum admins. Stay Safe - anyone can get scammed.
Brazing Cast Iron
- Thread starter van123d
- Start date
Hmmmmm.... Does that make you a crusty 60 year old out back?
Any what are you out front?
I'm just a crusty 49 year old. I started gas welding and brazing at 13 because i couldn't afford a mig welder but I saved up for a set of torches and a buzzbox. I had an Austin Mini that I rebuilt with gas welding and brazing. I had a really good mentor at the time who taught me the ways. He was the crusty 60 year old.
Its sad that brazing really seems to be a lost art in our throwaway society. Its like if it can't be mig welded we toss it and buy a new one. Gas welding/brazing is still a very valid repair method for stuff like this.
Its sad that brazing really seems to be a lost art in our throwaway society. Its like if it can't be mig welded we toss it and buy a new one. Gas welding/brazing is still a very valid repair method for stuff like this.
Proxule
Ultra Member
Ill jump on that boat too, but more like shipping and material. I work on IOU's
I am in Edmonton.
I have done some tricky stuff over the years, I think John C has posted about a little gearbox I brazed. Nothing fancy, But it was documented at least.
I also did my 1928 International harvester cyl head ( valve stem tower )
Plenty others too but that was the most recent and technical ( nearly 100 years of oil and abuse ). I find that cracks tend to propagate and open as soon as you hit it with the pre heat stage, Then you end up chasing the crack. So drilling a hole at what you suspect is the end of the crack really helps.
Go grab your self some dye pen and see if you can track the crack,
https://canadaweldingsupply.ca/products/magnaflux-liquid-penetrant-testing-kit
Or if you want I can send you a kit - I have several extras. ( Contact me in PM )
I would attempt to do it my self.
Forget TIG brazing,
KISS- Keep it simple stupid.
Either short stitches with Nickel 99 rod, Or low fuming bronze rod.
Preheat accordingly and post heat accordingly, I would argue the pre and post is as or even more important then the shiny snot you apply to the cast iron.
GLuck
Last edited:
I agree the pre and post heating are the most important considerations, whether brazing or welding. Some parts i've brazed on a bbq, but this one would need a small campfire because of the size. You'd need to get it to and keep it at probably 300F or so. Easily done.
DPittman
Ultra Member
I'm glad to hear that from someone else, I figured I only thought that cuz I don't do TIG and am dated and not with the times. It seems to me now days TIG replaces everything we used to braze but does it better (at least that is how I read it). My MIg has replaced any thin metal welding I used to do with ocy/acetylene but I still enjoy a braze weld every once I awhile.
Last edited:
One of the guys who taught me a lot was an excellent stick/mig/tig welder yet almost always brazed anything cast iron. Its a very strong repair if done properly, with much less chance of cracking. In fact, myself, I don't think I have ever had a cast iron repair crack when brazed. I have when I stick welded though. Sometime you have to chase those cracks. All welds shrink, all of them.......brazing not so much.
Dabbler
ersatz engineer
I was about to post Nickel rod when I saw @Proxule comment.
All of @Macgiver comments apply. With such a large piece, slow heating and even slower cooling is essential. As is stress relieving the entire piece before repairing it.
Remember there is a reason why it cracked - only sometimes the pattern points to an obvious solution. If you don't know the reason, it might very well crack again in the same pattern a half inch over. It happens all the time!
If many of them are cracked, then one solution is to have Windy Hill copy it in malleable iron. For 600$ each, your are in the right ballpark for WH to make you another. And malleable iron won't crack easily, nor propagate one.
Thanks guys for all of the great responses. Especially thank you to the offers to attempt the repair. If you guys weren't so far away I would take you up on that offer.
It is the size of the parts that makes this more difficult to me. These do not fit in an oven or bbq. and with the large surface area and thin cross section it would be difficult to evenly heat by torch and keep heat in the part. I do have a wood stove in the shop. I could potentially keep a fire going in the wood stove and keep the part on the wood stove. I could even do the brazing/tig/arc repair while it is still on the stove and it would be slow to cool as the fire burns down.
I requested a quote from that Duny company and will see what they come back with and go from there. I am not opposed to attempting this myself but if I can de-risk future issues by getting it in the hands of someone more experienced that is worth it to me.
So of the processes mentioned, Brazing, Silicon Bronze Tig, or Nickel Rod Arc. What is the least likely to crack? I am less concerned about what is the strongest as this is not a structural part.
I am an ok backyard welder for stick and tig. Nobody is putting pictures of my welds up on their walls but they are decent. But I have never tried silicon bronze or nickel rod. My welder is good to 200A stick, 150A tig. Would that be sufficient?
It is the size of the parts that makes this more difficult to me. These do not fit in an oven or bbq. and with the large surface area and thin cross section it would be difficult to evenly heat by torch and keep heat in the part. I do have a wood stove in the shop. I could potentially keep a fire going in the wood stove and keep the part on the wood stove. I could even do the brazing/tig/arc repair while it is still on the stove and it would be slow to cool as the fire burns down.
I requested a quote from that Duny company and will see what they come back with and go from there. I am not opposed to attempting this myself but if I can de-risk future issues by getting it in the hands of someone more experienced that is worth it to me.
So of the processes mentioned, Brazing, Silicon Bronze Tig, or Nickel Rod Arc. What is the least likely to crack? I am less concerned about what is the strongest as this is not a structural part.
I am an ok backyard welder for stick and tig. Nobody is putting pictures of my welds up on their walls but they are decent. But I have never tried silicon bronze or nickel rod. My welder is good to 200A stick, 150A tig. Would that be sufficient?
I'm somewhat surprised at the all the just do it guys, not that I'm any welding/brazing guru, but it is a really big part and given the thin section would be big trouble if not properly preheated i.e. 500-700F and then slowly cooled. It takes a big home shop to do that safely and one that has all the stuff, big rosebud, lots of space, blankets etc. Given the size of the part and large extent of the crack and brazing needed, you'd likely have to have one guy continually heating and the man brazing will probably need radiant heat PPE. No reason you couldn't do it in the home, just that most don't have all that stuff.
I've brazed cast iron a few times successfully but its the size and thin section that make this a challenge, imo. Or am I just being a sissy about it lol?
OP, I did point you to the right place, that was who we used. I was way off on remembering the shop rate so was a bit unfair to them. Still, it was expensive ...... don't throw out those US leads quite yet. Please let us know what they say.
I also forgot, I had a small crack on my bottom panel of mine and did as Sasquatch mentions. drilled a hole,used JB weld and drilled and tapped for some small braces across the crack on the inside. It is not a stressed part, but your cracks are extensive, not sure if it would work. Is Herculock suggesting stitch or brazing? I don't think they can stitch without it showing...but maybe there is new technique.
I've brazed cast iron a few times successfully but its the size and thin section that make this a challenge, imo. Or am I just being a sissy about it lol?
OP, I did point you to the right place, that was who we used. I was way off on remembering the shop rate so was a bit unfair to them. Still, it was expensive ...... don't throw out those US leads quite yet. Please let us know what they say.
I also forgot, I had a small crack on my bottom panel of mine and did as Sasquatch mentions. drilled a hole,used JB weld and drilled and tapped for some small braces across the crack on the inside. It is not a stressed part, but your cracks are extensive, not sure if it would work. Is Herculock suggesting stitch or brazing? I don't think they can stitch without it showing...but maybe there is new technique.
Last edited:
Proxule
Ultra Member
Nah, just an exp question. Or comfort level. Nothing more.
You have valid points and we all respect your opinion and view.
Proxule
Ultra Member
Least likely, braze. Easiest to apply with reasonable succes. 99 nickel, short stitches. Peening agressivly to ease the weld and surrounding area.
Dan Dubeau
Ultra Member
If it were mine, I'd be up for brazing it, because I find that enjoyable. But i'd also do a quick check of how much I could simply buy one for (if I could ifnd one), and how much gas and consumables I'd go through brazing it myself. Not to mention time involved. It would depend on my goals for the project too. Do I want to do every step of the process because I enjoy it, and want to step back one day and say "I did that", or do I simply want a working lathe, and will pick and choose my battles along the way to that end result. More and more I fall into the latter, but I certainly get drawn into the first goal quite a bit too.
trlvn
Ultra Member
Going back to the image van123d posted, there is no precision alignment required for this part, right? It is just a cover for the belts and gears?
It must have been an impact that caused the damage? If that is correct, I think epoxy would be more than sufficient for the repair.
Maybe it could be washed in one of the systems engine rebuilders use to give the epoxy the best surface to adhere to? Not even sure that is necessary. The repair just needs to be strong enough so that vibration doesn't cause it to crack into pieces.
Craig
It must have been an impact that caused the damage? If that is correct, I think epoxy would be more than sufficient for the repair.
Maybe it could be washed in one of the systems engine rebuilders use to give the epoxy the best surface to adhere to? Not even sure that is necessary. The repair just needs to be strong enough so that vibration doesn't cause it to crack into pieces.
Craig
DPittman
Ultra Member
And if the epoxy didn't work satisfactory enough, it could be cleaned off and then brazed in the end. I think I'd V out the cracks for the epoxy similarly as for brazing.Going back to the image van123d posted, there is no precision alignment required for this part, right? It is just a cover for the belts and gears?
It must have been an impact that caused the damage? If that is correct, I think epoxy would be more than sufficient for the repair.
Maybe it could be washed in one of the systems engine rebuilders use to give the epoxy the best surface to adhere to? Not even sure that is necessary. The repair just needs to be strong enough so that vibration doesn't cause it to crack into pieces.
Craig
Last edited:
MooseMeat
Member
Tig,
you can convert a mig welder to Tig for cheap, no AC though, that's how I got into Tig, a cheap Lincoln mig 140 with the gas solenoid , bought all the parts off scamazon, I was into it for less than $500 bucks. My Mig welder was a transformer type with a shitty duty cycle, after the conversion it seemed like I could weld for ever for some reason in Tig mode.
I did eventually buy a Tig welder (Everlast) but I still have the all the conversion hoses, it's really simple to do to get you started. Now I only use the mig for rude and crude welding. Oh, and the $500 bucks included the Airgas yearly rental, point to note on gas, if you mix the argon with a little helium you can increase the welder output. (google it) My local Lordco here in BC has a side deal with Airgas, if you buy direct from Airgas you get the "ouch" rental and gas price, all I did was ask and they gave me the Lordco pricing, my local Airgas guys are pretty darn good guys here.
MooseMeat
Member
FYI
you also can convert any AC DC stick welder to Tig, AC is per line frequency 60hrtz perfect for aluminium Tig, maybe some experts can jump in here to correct me, but it's really is shit simple, CRAP, I did it.
Re: your attached videos in post #16 above
YouTube welding info:
Agreed Moosemeat - both Jody at ‘welding tip and tricks’ and Justin at ‘the fabricator series’ are great YouTube sources - good info without the normal YouTube BS.
I’d also add ‘weld.com’ as an equally great YouTube welding info source. Weld.com uses several professional welders as the commentator, each with their own special skills.