Weld or Braze

[OH10]

I had an accident and broke off the casting for my 3-point hitch. Since it is cast iron would it be better to have it brazed or welded?

 

[jack707]

If it not weight barring I would brazed it.

 

[ArlyA]

Do note, if you braze it and that fails, welding it then is impossible, or next to. The bronze impregnates the materiel and can't be removed.

 

[DuckSlayer1017]

Maybe consider cutting it off flat, drill and tap some holes and get a machine shop to make a bolt on replacement.

 

[Tractor Seabee]

What's the price of a replacement part. Sometimes fixing cost more than a new part. A repair is never as good as the original, especially on CI. I have brazed a lot of stuff though that was the best and most economical solution such as the feet on machinery bases.

Ron

 

[Texasmark]

I have some cast iron welding rods and a manual that tells you how to do it so welding is performed professionally....to ask if it works and is reliable. I have seen brazed (brass rod) welds on CI. Never saw one broken, done right, in right application.

 

[aircommuter]

It looks like some kind of repair or cover up has been done previously in the one picture. What ever that material is on the surface would have to be thoroughly ground off to do any form of welding. To do it properly with someting that thick you need to remove the entire part, and grind a v-groove to get full welding depth, then with nickel rod for cast iron you need to pre-heat the parts and make short beads, peening immediately after each bead to relieve stress. Then that hole in the part will have to be re-machined.
Then you are still at the mercy of the quality of the casting and its impurities. So like another person said find out about the replacement cost and availability.

 

[OH10]

What's the price of a replacement part. Sometimes fixing cost more than a new part. A repair is never as good as the original, especially on CI. I have brazed a lot of stuff though that was the best and most economical solution such as the feet on machinery bases.

Ron

Thanks to everyone for the advice.

In order to replace the brake casing, upon which the broken casting is molded, I would have to pull the Axle and the axle casing. I will try to avoid that for sure since the repair manual states you need a chain fall to pull the axle off. I really don't want to deal with that.

As far as load goes, the epoxy repair held up for using the Augur but when I hooked up the subsoiler it broke as soon as I hit the first tough root.

I found a local guy who does a lot of on-site construction equipment repair. I'll trust his advice as to whether to braze or weld once he has a chance to look at it. If it breaks again I'll look into cutting it off flat and tapping it.

Thanks again for helping out.

Mike

 

[TemporaryKubotaOwnerMark]

1. Download and install XnView.
2. Open your photos with XnView.
3. Select, Image, Resize.
4. Choose a width of about 800 pixels, maybe 1000 max.
5. Select File, then Save As, and give it a new name.
6. Now upload a reasonably sized file that won't take forever to load. There is just no reason to upload ~3mb files on a forum.

And as for the part, fuggedaboutit. It's done. Face it now, or pay to repair and then pay to replace.

 

[Tractor Seabee]

Arc Braze Arc Welding Rods

Look into these products. I have never used this brand but used to use similar products by Eutectic.

The arc braze process works great on cast iron, follow their instructions on cleaning and pre-heating. Arc-braze is more novice friendly than the cast iron and nickel rods. Short learning curve, no peening required.

Ron

 

[DaveK OR]

Even a crappy-looking brazing job can be stronger than the part you are fixing. As long as you get good flow through the joint, it should be quite strong enough. The cast iron part is far more likely to fail at a crack (perhaps invisible) near the joint than at the brazed joint itself. People put down brazing as an inferior repair method, but it's still a very strong way to join metal parts, and can be done with just a torch, under field conditions. If done properly, the brazing metal flows across the entire joint, to give you a very strong connection. When you weld a thick piece like that, you probably won't get full penetration unless you are very, very good.

If you do go with brazing as the repair method, you might consider using a silver-based brazing alloy (sometimes called hard-solder). You can get it to flow at lower temperatures than some of the bronze alloys, and it is available in very thin sheets or flat ribbon. You can pre-flux the joint, position pieces of the brazing alloy directly in the joint, and then if you can hold it in position while you heat, you won't have to wick the brazing alloy into the joint. It's a tricky thing, but can result in a joint easily stronger than the metal. Silver-based brazing alloy is expensive, but you really don't need very much.

 

[Shield Arc]

I ordered these Silicon Bronze Tig rod a while back. I was shocked how easy they are to run.
3/32" Silicon Bronze Tig 36" Rod - 1 Lb - AWS A5.7 ERCuSi-A | eBay

 

[yomax4]

Bunch of different ways to fix this of course. I'm going to have to go with Cast Stick. Couple tacks and then take a die grinder and a carbide burr and eat a bunch of cast to get it beveled a little. Then do what the rod manufacturer suggests. I also like Nickel Free rod for problem cast but you may be ok with just basic 55-95%. keep it cool and multipass. If you did want to try to braze it, i would still tack with something and bevel a bit to get the filler in there a ways. I have some Harris Welco 14FC series Nickel Bronze flux coated rods that I would use for this If I was to braze it. You can braze overhead with this stuff and It has a good tensile strength. Would you be doing the repair yourself?

 

[DaveK OR]

I ran across a link to this stuff, which could do for your repair... The tensile strength isn't as high as a good brazing job, but for your needs it should work. even if it's down around 10,000 psi, you have enough joint area that it should hold under any load you might apply. A stronger brazed joint would be a bit better, but then you probably need to pull the assembly apart for the repair. The heat required for brazing might well be enough that you could damage nearby seals and gasketed joints. This stuff flows at around 400F, and you can fill the joint with the paste, clamp it together, then just heat it gently with a propane torch.

There is other stuff like this with different properties, and you might find one that has a bit more strength without having to heat it too much for the nearby seals and gaskets.

 

[tjflicek]

I ordered these Silicon Bronze Tig rod a while back. I was shocked how easy they are to run.
3/32" Silicon Bronze Tig 36" Rod - 1 Lb - AWS A5.7 ERCuSi-A | eBay

On November 9, 2012 you replied to my 1st post on this forum. I tried to suggest the attributes of Silicon Bronze TIG rod at that time, thought you might have tried it before now.

 

[Arc weld]

A problem with brazing might be the heat involved for proper fusion (for lack of a better term). It might burn seals in the diff.

 

[muddstopper]

Is that where the 3pt hitch arms mount. If so, lots of stress in that area. I did something similar several years ago. Broke both ears off the housing. They way I fixed it has worked for several years now so I will just pass it on. I did remove the diff housing, you just cant get the proper access with it still on the tractor. I bought some nickle99 stick rods and tack welded the ears back on the housing. I then did as was already suggested and ground the pieces down to a fine point, both sides. I would weld a bead on one side, then flip the piece and weld a bead on the other side. I continued to do this until I have the big Vee filled flush. It was tedious work, and I had to stop and hit the weld with a grinder every so often to knockout bird dropping welds and keep everything in proper shape, using some sort of weld backer would have helped a lot to prevent some of the dripping welds, but I didnt know that technique back then. When finished, a little sanding and some paint and you cant tell it was ever broke.

 

[RedNeckGeek]

Just the fact that it broke through such heavy sections shows that the part takes a lot of load. And whatever repair is used needs to be as strong or stronger than the original part or it's just going to break again. You can try a braze, which with the right alloy can be stronger than the original part, but you're going to have to be careful not to cook nearby seals or joint compound. Those heavy sections are going to need to get to near red heat, and you must NOT use water or any kind of forced cooling or you'll end up with a brittle part that will break the first time you shock load it. Nickel rod will work if you decide to weld it, but you'll need to make a full penetration weld by grinding a V on each side of the joint. I'd come in from each side, making a double V, put the root pass in one side then grind the other until I hit weld metal, then weld out from there. Same cautions apply with not force cooling the weld as brazing, so either way you stand a good chance of cooking nearby seals and joint compound. If cooking is gonna be a problem, you might just try the mechanical repair first and see if it holds. If it breaks again, you're going to have to disassemble to weld or braze, and at that point replacing the part with a new one might look pretty good.

Whatever you decide, post a couple shots so we can all see how it turned out, OK?

 

[OH10]

I want to follow up on this thread since the young man came out with his Thermal Arc 3 in one machine and did a very nice job on my broken casting. Here are some pictures. He told me he used both stick and wire.

 

[Dustind]

if its a hard cast it can be welded. brazing isnt even an option for you.