Challenging CRACKED Cast Iron Housing Repair! | Flame Spray Welding
how you going guys Kurtis from Cutting Edge engineering today's job we have a transfer case off a 966 Cat loader that's come in for a crack repair but before we get into today's video I'd just like to thank everybody who's donated and supported the GoFundMe page we set up for Matty from Matty's workshop for those who aren't aware Matty is battling cancer at the moment so if you'd like to support nutty there'll be a link in the description below or you can go and check out his YouTube channel and watch some of his videos it'll be greatly appreciated so what the transfer case does is it holds all the components that transmits the power from the engine through the transmission out to the tail shafts which then transfer that power into the diffs which allow the machine to go forward and reverse so this machine was bought second hand it is new to our customer but after doing a general service on it they noticed an oil leak they figured it would just be an O-ring after they removed the bearing housing which holds in the output shaft they noticed the O-ring was still intact and it was undamaged but they did notice there was a crack running through one of the bolt holes after they did a bit more of an inspection they did find other cracks through a couple of the other bolt holes and there was a crack running through the bottom of the bearing housing cracks like this are very unusual especially when there's no evidence to sort of tell you what went wrong there is no damage on the inside so I don't believe something inside failed causing the crack it could have been maybe the tail shaft broke free or a diff locked up and all that power went back through the housing and forced it to crack but the customer didn't notice any damage on the machine to correspond with what's happened here because this housing is nearly eighteen thousand dollars to replace it they have asked if we can have a go at repairing it so I definitely don't consider myself an expert when it comes to repairing cast iron housings especially something this size I did recommend to the customer that they go to another gentleman who has got 40 years experience in repairing cast iron and his success rates are very high but because he is one of the only ones around that still do it he is extremely busy and he is booked out for months so I'm going to give this my best shot and give the housing the best chance of being able to be repaired we're just gonna have to wait and see if this repair goes to plan the housing is extremely cold at the moment so those cracks are going to be closed up I am going to put a little bit of heat into the housing in order to get them to open up and expose themselves and we're also going to do a dye penetrant test so we can actually see them visually where they start and stop see the moisture so I'm going to be using our dye Mark flaw check system it is a four-step system so I'm going to give it a pre-clean then I need to spray on the penetrant that will then leech down into the cracks and that takes about 10 to 15 minutes just okay [destruction mode activated] holy cow sit good boy all right come on let's go so that's been about 15 minutes what I'm going to do now is wipe away the excess penetrant I will then use the remover to get rid of the residue then I can put on the developer which will draw the red penetrant through it to expose the crack it's gotta dry yet and now we can see how bad everything really is we have cracks through four of the bolt holes and one crack running around the bottom of the housing two of the bolt holes are quite bad they do have cracks running either side of the thread this bolt hole is definitely the worst the crack does run all the way through the threads and out into the housing [birds singing] hi [bird singing] [bird singing] [bird singing louder] so now we know where all the cracks are what I need to do is grind them out but I need to be careful what I'm doing there because if I don't get all of the crack out when I go and apply heat to this the cracks will start to run and then you can end up with an ongoing problem and the repair won't be successful so I'll be using a brand new carbide burr on a die grinder righto so I've got those ground out I'm not 100 percent sure whether we've got everything yet what I'm going to do is apply a little bit of heat to it and what that's going to do is force the oil that's trapped in the crack out and it will hopefully expose any more if I've missed any mmm I think we've got it so I'm happy there are no more cracks the next thing I need to do is preheat the part but before I do that I'm going to get everything set up so to apply the powder we're going to be using our UTP puddle gun it has a variety of different size tips and those tips are for different size jobs and different rates of deposition so there are a lot of methods in order to repair cast iron you do have your standard electrodes oxy brazing silicon bronze and tig brazing I prefer to use a puddle gun because it's what I've had the most success with on jobs like this there are a lot of electrodes out there on the market for cast iron but unfortunately what's available overseas is not available here and finding a good suitable rod for this sort of cast iron has been extremely difficult so the difference between a puddle gun and a rototec eutectic gun is a puddle gun is designed for stationary repairs and it is a hot process so the material must be red hot in order to apply the powder with the rototec gun they are generally done in the lathe with the part rotating and it is a cold process where the material does not have to be red hot in order to apply the powder and the powder we're going to be using it's mssa27 it is a high nickel based hard facing alloy and it is the best suited powder for doing cast iron repairs on housings and to help with preheat and post heat I am using barbecue burners that I picked up from my local hardware store they're very handy because they are very low profile I've retrofitted nozzles into the ends of them and they just simply hook up to a standard LPG bottle so I am using one two three blocks just to hold the burners flat and prop them up they are not a precision set that I use for machining these ones are damaged cast iron is quite brittle it doesn't have any elasticity compare to steel so it is extremely important to control your preheat post heat and your heat input I'll also be using an oxy and LPG kit with a heating torch to bring the rest of the housing up to temperature I don't want any cold spots in there so we're going to try and bring it up to about 300 degrees before we start the repair yep let that burn for a little bit longer so now that's up to temperature we can start applying the new material so when using a puddle gun you do need to get the parent material up to a cherry red color then you can pull the trigger and apply some powder once that powder wets in and blends into the material around it you can then build from there applying more and moving along the job I do not ever pull the trigger when the material is cold because the powder will not bond and you'll end up with a void in your repair [pop] [bang] [crackle pop] [Karen] why's it doing that no idea could be something in the tip [pop pop] just blowing the material out so I'm having a few issues with impurities being drawn out of the cast iron when I'm trying to apply the powder and that's because cast iron is what's considered a very dirty material and that is causing the spray material we're trying to apply to ball up and not bond onto the parent material it is also causing air bubbles and air to be trapped within the cast iron that then explodes and blows molten material back up inside the tip of the gun and that causes issues with trying to get the powder out of the gun because it is backfiring so because those impurities are being drawn to the surface I am going to use the die grinder just to remove them that way I can apply more material [CRACK] damn it righto guys so I heard a crack I did go and have a bit of a look for it I did find it coming back through another bolt hole and it is starting to run out into the housing so I did decide then that we were going to stop and maybe look at grinding that out and attacking that one but within a couple of minutes of stopping we heard a massive bang another crack had formed through another bolt hole at that stage I decided that was it we're stopping so I turned the gas off turned off the heat and within a minute or so there was a [gasp] massive crack through the bottom side of the housing that's cast iron for ya so that's been sitting there for a couple of minutes now without any heat on it and there are now cracks everywhere and that's why is so important with cast iron to preheat and post heat and let it come down to standard temperature as slowly as possible so the customer was fully aware that this may not work and he was prepared for that so because C I agreed to take this job on knowing full well that it might not work even though I do have a fair bit of time invested in this as well as powder and it is very expensive this is a failed repair so I won't be charging the customer so if this had been successful the next thing I would have done was set it up in the milling machine milled that top surface flat re-bored the ID to size and then drilled and re-tap the holes cast on is one of those problematic materials that is very difficult to repair especially when you're talking about a housing even though I've had a lot of success using the puddle gun unfortunately this one just didn't go to plan but I hope you enjoyed the video thanks for watching right so the customer first kno ugh noted [Karen] just not right so just so the customer so right [Karen] try not to use right so okay so the tran oh so I'm supposed to say so [Karen] yes right oh so I'm happy there are no more cracks the next step I need to ugh [ __ ] me [Karen] just no righto so all right right so I've preheated ughmmmm [giggle] right so the ughmm righ so mmm hmmmm MMMMmmm hmmMMHMm [ __ ] where are we going after that [ __ ] me now I'm really [ __ ] up [Karen] okay okay okay yeah I [ __ ] that up yup right so the customer first note uh noted so the customer first knows ohhh no no [ __ ] words man [Laughter] [ __ ] he needs speech lessons learn England [Karen] I think you should try not having coffee for a day and see if it helps are you [ __ ] serious [Karen] I'm serious Oh my God [Karen] your brain might be slower than your mouth then no the brain's already repairing it [Laughter] that's the problem the brains already in there doing it [Karen] and I'm like sloooww dooowwn [giggle] the mouths like mmmmm NO [Laughter] [Karen] where's the where's the spray bit someone stole it [sigh] [Karen] ummm who his name starts K and rhymes with Urtis [Karen] does it work still I'll use this one there's the lid oh [giggle] [Karen] why there we go [giggle] I got these free and I'm gonna say Saber and Carbide a lot [Laughter] kidding these were [ __ ] expensive [Karen] okay show me now just spin that one please like vertical oh my God HUH what the actual [ __ ] is going on [Karen] do you want to say anything yet or you want to just walk away [Karen] oh I don't like it don't like it at all it's not gonna explode [Karen] no but it's the anticipation of something [Karen] oohh [pop] [gasp] oh uh Jesus [CRACK] right you ready [chirp chirp] [chirping birds] can fit them into parts in order to preheat and post [ __ ] off this is not a zoo [ggigle] [Karen] yes it is Cutting Edge Zoo [birds singing loudly] hahaha [bird singing continues] [really LOUD bird singing] WOAH they're so loud [destruction mode ON] [giggle] Jesus hey enough watchu got come on go come on
2023-09-29 01:09
