In the Foundry and the weld shop, the Navy provided us with electric ovens that got as hot as 900 degrees F but until they installed the ovens we had some "old school" methods of preheating castings and assemblies. In the case of what you just brazed, we would preheat the casting by filling the void with charcoal (after all prepping was completed of course) light the charcoal then wait for the charcoal to be cherry red then the repairs would commence. This not only saved us the cost of using a torch to heat up the casting but it evenly heated the casting through out the mass to prevent intersticial cracking and when the project was completed, we allowed the coal to slowly die off which kept the casting from cooling too quickly and forming areas of stress. If you have more project like this one, this method might help!

My brazing skills have improved since watching your videos and your commentaries while performing the task. Thank you

Hey Keith, I deal with round channel letters and sign cabinets all the time. I learned a long time ago that when you're dealing with 2 sawhorses like that, it really helps to run a strap to keep them from spreading apart. Eventually, I made a 12" latch at both ends out of a piece of flat steel and studs. Works wonders! Figured I'd tell you my little trick, it's saved my toes more than once

excellent work keith, im glad you didnt edit out dropping the part on the floor, and talk about running out of gas. keeps the channel real. thanks.

Keith grinding & brazing; Folgers in my cup--a super start to the week. Keith seems to be on a "roller" coaster.

Great video Keith I loved that you showed it falling u could have edited it out but u didn’t just shows your human stuff happens to us all!

Keith you are a very lucky man that did not drop on your feet or leg . please take care we need you to post videos

19:18 was thinking - sure hope he has those saw horses clamped together. Good on you for showing what not to do. Reminds me of when we accidentally picked up parts before they fully cooled - "sure don't take long to look at horseshoes".

Thank you, Keith! Taking on these challenging repairs distinguishes you for the craftsman you are. 🇺🇸 St Marys, GA

Heavy casting, more brazing. Gotcha!

The brazing of cast iron never gets old. That was a big challenge and turned out nice. I was waiting to see if you chucked that big thing up on the lathe like they do on the Pakistan truck channel!

Fair play to you for including the bits where it doesn't go so well. Great job.

"That...was not the plan." Story of my life! 😂

The old double Kt fracture... Also known as a stress riser. They did some amazing mechanical design work back then given the technology of the day. We have learned so much over the years about the dos and don't of engineering... We stand on the shoulders of giants... Very Cool project. A generous radius in those corners may have saved that casting from a crack.

THANKS KEITH

Thanks for the education, Keith. I have something that needs to be brazed and I haven’t brazed anything in 35 years, but your clear descriptions of what you are doing and why have been building my confidence to the point that I will probably try to do the repair myself. Good content!

Excellent as always.

I appreciate you showing us all the goof ups, too many videos are edited to smithereens and you'd think guys never make a mistake. Moreover that looks like a good strong repair.

Thanks Keith, I would not have had the patience or the skills to do that. I hope the owner compensated you for all of the extra experience.

Hey, Kieth! If you want to save your torch gas and do better fast heat up of parts. Get you a propane weed burner wand to turn up high and blast the part big flame works well and fast!!!! Can even leave burner on part to keep hot as welding just turn down a little!

That was certainly a challenging project. I really enjoy you videos and the knowledge that you share with us. Thank you very much for sharing.

Have you tried brazing using the cutting torch tip? It has a more concentrated flame than a rosebud and puts out more heat than a welding tip. My dad always used the cutting torch when brazing heavier cast parts that needed a lot of heat.

You have so much more patience than me. I was praying that this wouldn’t turn into a two part video. 😅

Here you demonstrate every brazing attempt i have ever been in on - trial and error with all the various tools at ones disposal. Let the material guide ya as to how it wants to take -or doesnt. Very good of you to show the honest truth … every attempt is a challenge all its own and just working it thru with ideas and practice is what gits rrrrrrr dun! Great video and great work. I was taught to stop drill the end of a crack but others choose to grind cracks out entirely. I wonder which most people choose?

Wow, those were some serious cracks. Glad to see you got it done.

Thank you for sharing.👍👀

In my much younger days, I swept floors in an old school job shop (got in the way more than anything really). They used to get BIG gears all the time. Most were from very large old school punch presses. Most were more than 4-5' in diameter. I used to help build the "furnace" using fire bricks around a big section of the gear, sometimes the entire gear. Large propane torches were used to heat the gear. They would frequently let them burn all night to get them up to temp. This was obviously after they prepped the crack or missing tooth area by spending hours grinding. When the gear was up to temp, out came the OA torch. They didn't mess with single large tips, they went right to the rose bud tips.The brazing rod must have been at least 1/4" in diameter, maybe bigger. They sometimes had to do complete build ups of a missing tooth. Once the brazing was done, the gear was moved to a huge lathe to clean up the outside and sides of the tooth or repaired area. Before it could be moved, it had to cool slowly under fire blankets and layers of insulation. I wish I could remember how they did the tooth faces, Regardless, the whole process was really neat and took numerous days to complete.

For heating a large casting some Kayo wool insulation and a propane weed burner is very efficient in cost, time and effectiveness. You can literally get the whole casting glowing cherry red if you so desire. It isn't really necessary to do that of course to braze but it will allow you to get a good heat in the entire part before you start on the repairs and to warm it up if you lose heat.

Amazing job👀.....Thanks Keith 👍 Shoe🇺🇸

Great job Keith, not an easy piece of metal. I think I would have tied the horses together at each end to keep them from separating, just a thought. Thanx for sharing.😃

19:19 Ouch. Glad you weren't hurt. Steel toed shoes ftw.

A propane tiger torch helps get the heat in to the past, it's also easier on the acetylene to only use the brazing tip.

Here in Arizona, we just place the part out in the sun for a few minutes for Pre-heat treatment, then Braze it, for more difficult projects, we just leave it out a while longer and it melts right back together!

The Liberty bell! Thanks for sharing.

A firebrick brazier is mentioned below. I wondered about that as you started. I disagree though on his conclusion. I've seen heavy pieces like that in service for literally decades after the repair. If it doesn't fail in the first hour it likely won't.

Given some of your more difficult brazing jobs you've been handling doesn't your wife need a new oven? I mean...PERFECT excuse to get the old oven in the shop, and she gets a new oven. Of course that new oven comes with a new Kitchen, but hey...LOL.. Nice job Keith, can't say I didn't see the drop of the roller though, I saw that one coming a mile away. LOL. Glad you're OK after that, kind of scary!

challenging job there Keith, well done

That one's a hernia maker! Nice work.

Wow... did you ding the floor? Crane just paid for itself again.

Any foundry man or pattern maker looking at that would just shake their head and sigh. Most of that cracking has its origin in poor design. Heavy section, light section, no provision for contraction across those four ribs. If they had just designed it with three ribs instead of four it would probably not need repair even now. 😢

An encouragement to us all. Thanks for instruction!

We used to call the braze “pasty” when it was melted but not thin like water.

Great one. I was almost going to skip. (Another brazing video...), but man, you always make it interesting. I was half wondering if you were going to stick that beast on a lathe to clean it up! (Do you have a lathe that is hefty enough to handle something that big? )Also, was on the edge of my seat when you were repositioning with the welding blanket. Great drama! I'm glad you were not hurt when it fell!

Something that big... you could set it up on a gas fired fish-fry burner and heat soak it pretty good.

Good stuff

You do great job on your brazing..i would melt the rod with the pool instead of putting flame directly on welding rod..it makes a smoother weld..

Know an old timer that uses an induction cooking hob to pre heat his cast iron weld jobs.

Great video Keith, keep'um coming..

Noticed small crack that delaminates outer teeth from inner ring where you fist brazed. Looks previously welded and stresscracked.

Tell your customer about Clark at Windy Hills Foundry. If it cracks again, a new casting should be considered. Great Job. Thanks

excellent weld. If this wasn't 1 mule power, i would suggest drilling and pinning with 5/16 hardened rod, but you got this done right

When I have to heat a large part like this I use a propane weed burner, since you don't need the high temperature of the torch for the preheat and the weed burner is a large spread out heat source you can preheat a lot cheaper and sometimes faster since the larger area of cooler flame lets you get more aggressive with the total heat going into large parts at once, you can also set the propane burner under the part on low heat to keep heat in the parts further away from your work area. I guess you wouldn't be able to use this method in tightly enclosed spaces though, due to CO and other concerns, but it works great with good ventilation.

If you were doing a lot of this kind of work you could get a pottery kiln for pre heat and post heat for stress relief but they are not cheap , even used .

I’m not a machinist, but I was a mechanic for many years. I would have ground off that hideous flashing!!! Guaranteed more cracks will grow from those stress risers. That’s even worse than the 427 SOHC Ford block castings, which had the worst I’d ever seen in a running engine.

Wouldn't it be a good idea to drill the end of the crack of the drum before heating for the top repair? This should limit the crack opening to a minimum.

When those saw horses started spreading I was thinking :"Don't drop it on your foot!"

Thanks for the video Keith, quite a few dollars worth of gas on this project

I brazed up a broken handle for my vertical mill and was hoping like in soldering if i got some flux down in the crack area that i could not grind out would it "flow" into that area? like the way solder will "wet " into the metal... nicw job by the way..i learn a lot of brazing and other tips from your channel.

thought about using a gas hob to heat the castings? aside from that, i guess you're gonna have to weld on some chain stays for your saw horses.

Years ago I used an asbestos based damming material, can you use the material that you use for babbet bearing pours to do the same thing?

Very entertaining

Curious when we will see more about the stoker engine. Last I heard Adam Booth gave up on it.

Looked like there was a very worn bearing journal on that shaft that maybe could have used turning down or building up and turning down. I wonder if using a couple of carbon blocks as dams on either side of those webs would have made the brazing easier? It could have kept the braze from leaking out with higher heat.

Good video Keith. Did these "kits" still use babbit bearings? Seems like a lot for a farmer to cobble together. Thanks again.

Hey Keith, I am curious why you didn't drill out the end of the cracks. Perhaps it wouldn't do much good in preventing them from propagating?

Great brazing work but I thought for sure you would have the saw horses clamped together.

A better way to repair cast iron with gray iron rod. Most welders don't know about it but my boss has been using it for many years and thinks it's far better than brazing. Try it out.

You're a braver man than me Keith, that roller has been seriously abused in it's time and is cracked everywhere. I wouldn't have touched that job. Simply not worth the time, gas and future trouble it may bring into the shop!

That must have been some mule to crack that roller.

With a part that big you need a coal fire to get it thoroughly heated. That’s the way it was done in the old days way before we were born. Hopefully we’ll get some feedback a few years down the road to see how well they held up.

You know that material you use to dam up for pouring babbit? Could you not use that to make a dam to keep the braze under control? Just a thought.

Did you drill a hole where it ended on the face of the cylinder? My Maternal Grandfather said always drill a hole at the end of the crack to keep it from cracking any farther.

Looks like it could use some shaft repair as well. That is a hard part to braze with the mass.

A propane weed burner would be great to preheat parts, cheaper too.

Ive always wondered if on these large pieces one of those propane weed torches wouldn't be the way to do a preheat vs oxy acetylene???

A better tool to create your weld prep would be to use carbon arc, given your welding skills this would be faster and reach further into the parts that a grinder. It would also have a benefit of imparting some heat. great work thanks Richard

Would the clay play-doh stuff you use to dam up openings when you pour babbet help to keep your braze from slumping down the sides? Also, do you normally use that powdered flux when you’re brazing?

Keith just 🤔🤔you could for future projects like this one MIY cheap refractory oven. Using a roll of refractory wool and a propane weed torch placed in a 6" deep dirt pit in a metal trash can or large dia scape pipe piece and a stand for the part. 👍👍👍👍👍👍

Keith: I am curios if it would be helpful to drill a hole at the end of a crack to keep it from running any more?

Keith, I notice that you wear a Philmont belt. Were you a Boy Scout? I'm 69 and my brother is 73, we were both Eagle Scouts back in the day. I love your videos. Thanks as always.

how would using a turky fryer burner set part on it and then braize it

its a shame you cannot lay down some sort of a ceramic first. like to cast a plaster or a fire putty / fire cement to make a dam on either sides. or even somethiing else like a clay or concrete or sand whatever might work idk. for the heat loss you also kindda want the main body of the part half sitting over a fire or a furnace maybe? but it would need to be at an even and controlled temperature. all pretty challenging i cannot really fathom

You said for PRI heat and cool down "take a little Willie" so that's about the same amount of time correct?

Have you ever considered spray welding for repairing cast iron, such as a stoody torch.

I'm curious to ask why you didn't drill the end of the cracks to stop them from starting up again? Eric

Hi Keith, why don't you made a role in the end of the big crack to stop it?

Would it be helpful to sit the part on a large burner (turkey fryer etc) to keep heat in it while you work on local areas?

Maybe setting it in an old pottery kiln would work for preheating it.

If I were you kieth immediately after getting the roller repositioned, “Here we have this crack that was definitely not created by it falling on the floor.”

In hindsight, couldn't a drill have been used to drill out the web crack?

would it be worth useing an arc gouge?

Very interesting repair! I wonder if gouging rods would be helpful at getting into those hard to reach places with the angle grinder. Or would those heat up the casting too much as they gouge away material?

I've often wondered about making a pipe or burner arrangement for preheating. When I worked at LeTourneau, the welders had a black pipe with holes drilled along it. They'd weld it to the bucket lip and preheat with natural gas, think a 15 foot long bbq burner. It usually took 4-6 hours for it to be at 400 degrees or so. They also left it running as they welded, to keep the heat in the part. I don't remember how long it took to weld that up, but the bucket was for the L-1100, maybe 6 inches thick? And it was a long wearing type steel, not mild steel. That bucket held 11 yards of material. We had a bucket for wood chips you could order that held 20+ yards. When that horse moved the first time, I almost yelled out don't move that again!!!! I figured a chain on each end would keep the horses from moving apart. Glad you didn't get to balance that on your foot...

How was this roller damaged the way it was? The location of the cracks leads me to think that it was dropped or something. To much torque on the shaft?

Do you think it was a bad casting or something else like weather etc that caused all the cracks? That reminds me of an old saying "Gas, brass or... taps 🤭 nobody rides for free"

I hope Keith is being handsomely rewarded in the form of cane syrup. He can use it to make Ice Cream !!!

a lot of gas and a lot of brass on this one. Do you always use the prefluxed rods? I find them very expensive here in Australia, close to $10 each, so I almost always use bare rod and dip in flux when brazing.

Any bigger and you'd need to dual wield.

3:03...THOSE ARE THE BREAKS-(?) (get it? get it? get it? snucker-snucker-snucker-snucker!!!)

The bearing shaft looks kinda rough for a bearing surface?