1 time, my buddys old ranch tucks front axle shaft came apart and broke a 4 inch round hole in the tranfer case . Took it to the local welder, and he said he can't guarantee it will hold and would not touch it. Next, we Coundnt find one at the junk yard or even new housing for that truck was obsolete, so we went over to local parts store and got JB weld clay type and mixed liquid type. And got a wire mesh. We scuffed it up good and put wire mesh over the hole and applied clay tipe first,let it drye and then we applied liquid type over it and so far its been over 10 yrs still holding t-case fluid in. Last resort kinda deal 👌
That was a great repair, certainly was not easy. In my youth I learned to weld aluminum MIG with a spool gun it was not easy, but I learned it, this was in the 1980's, one day at a friend's house I was talking about welding aluminum with a spool gun and how hard it was, my friend's grandmother said that it's much more difficult to weld aluminum with a gas torch....! She was a weldor at one of the Boeing plants during WWII and she welded aluminum with a freaking gas torch... much respect!
I've been in repair situations with thick aluminum parts where that's the only way to get them hot enough to weld a nice big gas tip and some filler rod.. if you think about it a tig torch is doing the same thing just with electricity.
Isaac all your effort was not in vain , it gave us a view of what is involved in trying to fix caste aluminium, this one went the wrong way But you can’t fix everything, you are still the master of your profession, all the best from Tasmania Australia 🇦🇺
That was a nightmare. Aluminium castings are extremely difficult to weld at the best of times, never mind trying to repair some else's repair. It looks like that last repair was done with oxy. The case should have been scrapped in the first place and just replaced.
Patience of a saint Isaac . I would have definitely told them, well you shouldn't have tried to fix it before, and say you need another case because it would cost more than another case to repair it .
Every time I watch you work I learn something valuable. Added to that you manage to inject some humor in whatever the project is. In my opinion, one of the best channels on all of UA-cam. 👍🏼
That t-case is going on market place and some poor kid will probably think it’s a good deal not knowing it’s welded. Wheels, t-cases, transmissions….only do them for people I know and I usually leave them as welded so people can clearly see it’s been repaired. It looks like a decent repair 👍
Isaac, I admire you for even attempting that repair. If you or the customer had had access to a mill it would have been interesting to see if you could have built up weld in the area where the case was warped and then mill it back down to flat with a precision mill. Enjoyable to watch your work in any event.
I got to the end . Man Isaac, after all that work it didn't work ?... Still I hope they didn't refuse to pay though . All I can say is you're a hard working humble man Isaac . :)
Hey sir, I've learned a lot from you. I've been a welding student for about a year. Today I did some arc gouging. I thank you and keep the videos coming.
Most cases are so readily available these days that they shouldn't have wasted your time. If they had brought it to you first, you probably could have saved it. Still enjoyed watching. Thanks for your time.
I broke one of those 30 years ago. The pressed metal planetary exploded putting a square or rectangle hole right through the case. The gasket and bolt area were not affected. I just trimmed the broken parts off the ground it neat and welded in a plate, lasted ten more years, and over 100k mi. Then it was sold off.
Watching what you were doing to clean it up makes me think of that cheap low temp "welding rod stuff" that is advertised all over at the moment Shame about the outcome though, its not often something like that doesnt work for you, you did some truly impressive work on that casing.
Wow! Give you credit for tackling this job. As to addressing the gap between the case i would have masked one side and jb weld the other side (gap), bolt together and let set.
Good job Isaac for what you had to work with, they had absolutely cooked that cast aluminum before you ever received it, it is difficult to play second fiddle and come out on top !! 🤗
Every time you grind away some porosity from the botched first repair you just get into more and more porosity. Wild. That first repair looks like it was done with a gas torch.
I do appreciate all the effort you went through to make this video. Unfortunately for the customer I know they spent more than the cost of a used junk yard transfer case just in your labor to clean out the old welds, let alone your labor cost to weld it. A new case half from the dealer is only $3-400 last time I bought one.
Not at all, the case was damaged by whatever it first hit. The case was then ruined by whoever thought they were welding aluminum. Issac got close but ideally the case half would need to be surface planed or ground to get a seal surface again. Too much cost to make it worth while… replace the case
I am shocked. You reserved all that tedious die grinding for your personal viewing.... LOL Great work Isaac. Few folk would even attempt the job. The previous comment hit the crux of the problem. Alum castings look so nice until you try to weld them.. It is funny the crud doesn't seem to affect the casting quality.
That stuff is my fave to repair have been doin that kind of repairs for over 50 years. Lots of antique motorbike parts. Take alot of pride in my repairs. Cast aluminum is a different kind of repair.
Looks like it was done with a spool gun initially.... no Bueno 😂 fixing these type of castings in the best case scenario are really tough. Look good now👌
You win some,you lose some! You gave it your best shot. That's all that matters. I'm not sure what those cases cost but for the time you put into fixing it,I would think it would have been better for the customer to invest that money in a new one. Just my 2 cents! 😁👍
Nothing ventured nothing gained! I’ve spent my entire life repairing machines of all sorts, No matter the outcome ya just got to keep on trucking. This job you took on wow what a mess to try and repair someone best try!
Can’t help it bud.. every person has a different perspective but not everyone has really done aluminum cast! Again it stinks and most times breaks in the hardest to weld places! Rims, boats, door frames are considered a clip excursion. Always easier to weld but create hydrogen when welded. Seen some X-rays of new welded and it’s a sponge! Believe me after 30 years of welding it it is what it is bud.. swiss cheese pard! I love how you take anything on just to try. Gets me in trouble all the time but love it when it works out! A heavy coat of black paint will work wonders on cast aluminum pin holes. Thanks for your time bud. Your patience alone is worth $
I think part of the problem is welding a cast work peice. Of course cast aluminum has pores that randomly appear after being remelted. Much respect because of the best effort possible! I guess IF you were set up to be a foundry a chunk could be cut out then modeled up then cast from aluminum and stuck in place.
You did really well on that. If they had got it to you before the other guy had a go, I think you would have saved it. Sadly with the amount of distortion, that was never going to be easy. Nice work though, some you win ...
Good try!.. Monday morning quarterback on what I'd have tried is to cut a thin slice near that bolt boss, clamp everything down tight, perhaps even with a thin feeler gauge under a couple of the neighboring bosses, weld everything else, then weld up my cut and hope it comes out close enough to straight to be able to sand it flush. definitely not easy to work the impurities out of that cast though and sure makes a decent weld on top much harder to do
Well, can't blame you for not working out. You may have been able to save the piece of you had first attempt. I've got an aluminum oil pan from my old Bobcat. 20 HP Kohler horz.twin. the starter mount snapped off. Sort of a weak looking affair. I was able to find a " marketplace" used replacement. If something happens to this one, I'll drive down from Wisconsin!:)
Just returning a favor bud.. I have done many repairs to aluminum casting. Transmission and transfer cases. If you have a old stove whether gas or electric it works great for preheating and boiling out the crap slowly! You can always throw it back in a couple of minutes. Two three times per side. Second you will never get all the porous welds clean! Its a nonferrous spounge. Set your cleaning action at max.. run your beeds cool slowly and even when you buf it down rarely will it leak with a few holes! Good luck pard! Ps the profax 1260 gun is awesome
My initial thought is it does not look like aluminum but alumiweld or similar 'repair' rod, especially when the thin piece on the inside was chiseled out. The bubbly outside look seems to say excessive heating with the torch because the casting had gotten oxidized and the alumiweld would not stick?
Oh NO, NO, NO Hey man that transfer case is Magnesium. You need magnesium filler rod. I ran into the same problem several years ago, had one that had a small hole worn into by the chain, I cleaned, stainless brushed and tig welded with 4043. Was putting my stuff up and heard a little pop sound , the filler metal popped up a little . Tapped it with my hammer and it popped out. I figured it out finally and ordered some magnesium filler rod. It worked
Even if it didn’t get used it was still an entertaining video. There is only so much you can do with JB Weld and a bubble gum weld somebody else attempted to use.
It looks like the previous repair attempt was done with a spool gun and no thought was given to keeping alignment, not just on the mating surface but of the bores.
I have found if you use the gas ax to burn the oil out with the oxygen cutting lever depressed not trying to heat the part up gust burn oil off it works well to clean up cast aluminum
A difficult repair at best nevermind it's second go at being repaired, cast aluminum never welds well and there's no guarantee that it will be successful, still an excellent example of the challenges this type of repair offers
With aluminium it is possible to heat it up so hard soap burns on its surface then quench it. This will remove all the work/age hardening the aluminium has received. Also during this heating process it will show up if there is any oil trapped in the aluminium as it bubbles out.
At first when you put that aluminum in front of the heater, I thought you would have tried to trick us into thinking it melted from getting to hot. lol It was a good effort in trying to fix it though.
Welding, Aluminium Crankcases, Gear Boxes etc can be a pain ??? The primary work in my shop was previously Repairing Aluminium Casings. The jobs that look like would be a absolute pain actually went really well. Where as Cases that should be fairly straightforward were absolute Nightmare. Unfortunately, with some jobs I had to simply give up and hand the part back to the customer without completing the Repair ?? It's not a great feeling to simply give up from the sake of failing ??? But, some Cases were totally un-repairable no matter how much effort I put in.
I'm thinking the original repair was with one of those weld sticks and an propane torche you see at the the county fair booth. They probable have a use but not in this case.
Atleast it was an interesting learning experience. If it was me doing it would have just JB welded it feom the first break for a "cold" weld, if it holds oil keep trucking. The first job was a good example in epic porosity.
I agree. Should have been melted down. That said I have had “MINIMAL” success in the past by taking the support ribs from one side of the case and building matching ribs on the other side especially around the bolt holes. Then building up the low spots a filing them down as I went along. As I said minimal success. Good luck
Is there a certain temperature you need to get the casting to and maintain at while adding weld? How do you know if setting it in front of the heater is adequate or not or to hot?
Hi Isaac! Excellent work considering the existing damage. if you weren't able to bend that housing back into alignment, would lapping the mating surface would have worked?
A replacement case would be cheaper than your time although it's a common failure so maybe there's no stock anywhere? Either way your welds are certainly 10000% better so at least it has a chance.
1 time, my buddys old ranch tucks front axle shaft came apart and broke a 4 inch round hole in the tranfer case . Took it to the local welder, and he said he can't guarantee it will hold and would not touch it. Next, we Coundnt find one at the junk yard or even new housing for that truck was obsolete, so we went over to local parts store and got JB weld clay type and mixed liquid type. And got a wire mesh. We scuffed it up good and put wire mesh over the hole and applied clay tipe first,let it drye and then we applied liquid type over it and so far its been over 10 yrs still holding t-case fluid in. Last resort kinda deal 👌
That was a great repair, certainly was not easy.
In my youth I learned to weld aluminum MIG with a spool gun it was not easy, but I learned it, this was in the 1980's, one day at a friend's house I was talking about welding aluminum with a spool gun and how hard it was, my friend's grandmother said that it's much more difficult to weld aluminum with a gas torch....! She was a weldor at one of the Boeing plants during WWII and she welded aluminum with a freaking gas torch... much respect!
Ya never know who you’re talking to eh? ;)
I've been in repair situations with thick aluminum parts where that's the only way to get them hot enough to weld a nice big gas tip and some filler rod.. if you think about it a tig torch is doing the same thing just with electricity.
This is a great example of the difference between a professional tradesman and an amateur hack.
You must be the only person in Texas with a space heater running at the moment! Nice work Isaac.
I am! haha 🥵🥵🥵🥵
Isaac all your effort was not in vain , it gave us a view of what is involved in trying to fix caste aluminium, this one went the wrong way But you can’t fix everything, you are still the master of your profession, all the best from Tasmania Australia 🇦🇺
That was a nightmare. Aluminium castings are extremely difficult to weld at the best of times, never mind trying to repair some else's repair. It looks like that last repair was done with oxy. The case should have been scrapped in the first place and just replaced.
ua-cam.com/video/k6OH2YpJuEA/v-deo.html
Patience of a saint Isaac . I would have definitely told them, well you shouldn't have tried to fix it before, and say you need another case because it would cost more than another case to repair it .
Exactly, I can't believe that a used case wouldn't have been way cheaper
Junkyard np231 or 242 or whichever it is, would cost less than the weld bill.
You're the man. One of the best videos ever. Everyone is so used to clean new stuff. This is reality folks.
Wow. Thats all i can say. Anyone thats ever tried to weld cast aluminum like that knows how difficult that is.
Every time I watch you work I learn something valuable. Added to that you manage to inject some humor in whatever the project is. In my opinion, one of the best channels on all of UA-cam. 👍🏼
Better effort than the first guy, can't win them all👍
Shit. Isaac won. Got paid for the job. At least I'm assuming. 😂
That t-case is going on market place and some poor kid will probably think it’s a good deal not knowing it’s welded.
Wheels, t-cases, transmissions….only do them for people I know and I usually leave them as welded so people can clearly see it’s been repaired. It looks like a decent repair 👍
Sounds about right. Millennials are not the most trust worthy.
That "mess" turned into another work of excellence out the door!
A lot of work by all parties for a $200 side cover, or $500 complete transfer case. Thanks Issac for the content.
Nice try Isaac. Your skills always shine through no matter what the outcome is! Thanks for posting and take care!
Isaac, I admire you for even attempting that repair. If you or the customer had had access to a mill it would have been interesting to see if you could have built up weld in the area where the case was warped and then mill it back down to flat with a precision mill. Enjoyable to watch your work in any event.
I got to the end . Man Isaac, after all that work it didn't work ?... Still I hope they didn't refuse to pay though . All I can say is you're a hard working humble man Isaac . :)
Your work was a success for what you had even if they didn't use it.
Hey sir, I've learned a lot from you. I've been a welding student for about a year. Today I did some arc gouging. I thank you and keep the videos coming.
Most cases are so readily available these days that they shouldn't have wasted your time. If they had brought it to you first, you probably could have saved it. Still enjoyed watching. Thanks for your time.
I totally agree!
I broke one of those 30 years ago. The pressed metal planetary exploded putting a square or rectangle hole right through the case. The gasket and bolt area were not affected. I just trimmed the broken parts off the ground it neat and welded in a plate, lasted ten more years, and over 100k mi. Then it was sold off.
Watching what you were doing to clean it up makes me think of that cheap low temp "welding rod stuff" that is advertised all over at the moment
Shame about the outcome though, its not often something like that doesnt work for you, you did some truly impressive work on that casing.
damn surprised the repair didn't work. you made a great attempt... love your work
I can only imagine how hot it got in your shop with the heater running. Kudos on the effort which I'm sure could be measured in sweat.
Wow! Give you credit for tackling this job. As to addressing the gap between the case i would have masked one side and jb weld the other side (gap), bolt together and let set.
Nice fix, congratulations on the new gear!
You are just so sensitive to the metal and do such dainty work I think those like yourself deserve far more credit than you receive.
Good job Isaac for what you had to work with, they had absolutely cooked that cast aluminum before you ever received it, it is difficult to play second fiddle and come out on top !! 🤗
Hell of an attempt. I would have walked right off the bat. I commend your abilities!
Every time you grind away some porosity from the botched first repair you just get into more and more porosity. Wild.
That first repair looks like it was done with a gas torch.
Thank you for sharing, i learn a lot, another great video,always a pleasure watch your video,have a nice week end 👍👍👍👍
It reminds me of a dentist , you and that grinder , in fact they could show this episode to dental students ! Thank you for the video as always !
I do appreciate all the effort you went through to make this video. Unfortunately for the customer I know they spent more than the cost of a used junk yard transfer case just in your labor to clean out the old welds, let alone your labor cost to weld it. A new case half from the dealer is only $3-400 last time I bought one.
That base with the grooves looks like a table off of a shaper, probably a pretty good sized one.
Big Radial arm drill
1:57 that gap also probably contributed to the failure since it could be over torqued there forcing it and causing stress till failure.
I think bouncing over a rock contributed to the failure 😂 The gap was a result of the first person’s attempt to fix it
Not at all, the case was damaged by whatever it first hit. The case was then ruined by whoever thought they were welding aluminum.
Issac got close but ideally the case half would need to be surface planed or ground to get a seal surface again.
Too much cost to make it worth while… replace the case
I am shocked. You reserved all that tedious die grinding for your personal viewing.... LOL Great work Isaac. Few folk would even attempt the job. The previous comment hit the crux of the problem. Alum castings look so nice until you try to weld them.. It is funny the crud doesn't seem to affect the casting quality.
You're an artist, my friend. And I hope you got paid what you're worth for doing it. 👍
IC Weld to the rescue, well done. I would be very happy with that repair
That stuff is my fave to repair have been doin that kind of repairs for over 50 years. Lots of antique motorbike parts. Take alot of pride in my repairs. Cast aluminum is a different kind of repair.
Was waiting for you to upload a new video. Always enjoy watching you work Isaac.
Thank you for the content. Your schooling on the videos is fantastic.
Well done Issac very nice thanks for the video ❤❤ it. Take care of yourself and family and be Blessed ❤️.
I hit pole while doing wheelie and used some J-B epoxy to patch the cover to avoid trying to welding aluminium again.
That cover has seen better days.
That looks like an NVG 241 housing. There are thousands of them in recycling yards. I bought a low mileage one for $140.
Looks like it was done with a spool gun initially.... no Bueno 😂 fixing these type of castings in the best case scenario are really tough. Look good now👌
Tig and mr professional for the winn ,great job and awsome vidio!
Good work👍
Metal magician!!
You have amazing skill ....
You win some,you lose some! You gave it your best shot. That's all that matters. I'm not sure what those cases cost but for the time you put into fixing it,I would think it would have been better for the customer to invest that money in a new one. Just my 2 cents! 😁👍
Nothing ventured nothing gained! I’ve spent my entire life repairing machines of all sorts, No matter the outcome ya just got to keep on trucking. This job you took on wow what a mess to try and repair someone best try!
Can’t help it bud.. every person has a different perspective but not everyone has really done aluminum cast! Again it stinks and most times breaks in the hardest to weld places! Rims, boats, door frames are considered a clip excursion. Always easier to weld but create hydrogen when welded. Seen some X-rays of new welded and it’s a sponge! Believe me after 30 years of welding it it is what it is bud.. swiss cheese pard! I love how you take anything on just to try. Gets me in trouble all the time but love it when it works out! A heavy coat of black paint will work wonders on cast aluminum pin holes. Thanks for your time bud. Your patience alone is worth $
I think part of the problem is welding a cast work peice. Of course cast aluminum has pores that randomly appear after being remelted. Much respect because of the best effort possible! I guess IF you were set up to be a foundry a chunk could be cut out then modeled up then cast from aluminum and stuck in place.
Darn fine effort Issac. I think that You would have been successful if You had the first try at it. Thanks for sharing.
agreed
Amazing repair!
Great work welding on that aluminum
I enjoyed your video !
You did really well on that. If they had got it to you before the other guy had a go, I think you would have saved it. Sadly with the amount of distortion, that was never going to be easy. Nice work though, some you win ...
Always learn something from you. Great job
Good try!.. Monday morning quarterback on what I'd have tried is to cut a thin slice near that bolt boss, clamp everything down tight, perhaps even with a thin feeler gauge under a couple of the neighboring bosses, weld everything else, then weld up my cut and hope it comes out close enough to straight to be able to sand it flush.
definitely not easy to work the impurities out of that cast though and sure makes a decent weld on top much harder to do
Well, can't blame you for not working out. You may have been able to save the piece of you had first attempt. I've got an aluminum oil pan from my old Bobcat. 20 HP Kohler horz.twin. the starter mount snapped off. Sort of a weak looking affair. I was able to find a " marketplace" used replacement. If something happens to this one, I'll drive down from Wisconsin!:)
KEEP UP THE GOOD WORK
Great video thank you for sharing
Dude that is awesome
Just returning a favor bud.. I have done many repairs to aluminum casting. Transmission and transfer cases. If you have a old stove whether gas or electric it works great for preheating and boiling out the crap slowly! You can always throw it back in a couple of minutes. Two three times per side. Second you will never get all the porous welds clean! Its a nonferrous spounge. Set your cleaning action at max.. run your beeds cool slowly and even when you buf it down rarely will it leak with a few holes! Good luck pard! Ps the profax 1260 gun is awesome
👍👍👌👌 Thanks for the video!
nice repair
Man you know how to pick them
Couldn’t they get another case ?love your work🇬🇧👍
Yup. Most of them are stupid expensive.
Doubt that unless it’s rare . That’s not
@@AndyL940 yeah, just looks like an NP241 or later variant
yup 241
My initial thought is it does not look like aluminum but alumiweld or similar 'repair' rod, especially when the thin piece on the inside was chiseled out. The bubbly outside look seems to say excessive heating with the torch because the casting had gotten oxidized and the alumiweld would not stick?
Oh NO, NO, NO Hey man that transfer case is Magnesium. You need magnesium filler rod. I ran into the same problem several years ago, had one that had a small hole worn into by the chain, I cleaned, stainless brushed and tig welded with 4043. Was putting my stuff up and heard a little pop sound , the filler metal popped up a little . Tapped it with my hammer and it popped out. I figured it out finally and ordered some magnesium filler rod. It worked
141👍's up IC WELD thank you for sharing
You gotta try some Plantex flap wheels with Kangaru oil! It removes material so fast and no gumming! A simple cleanup with acetone and away you go.
Good thing you had to run your heater. Heard it's been mighty cold down there in Texas. 🤣
That's the "Attack of the Spool Gun".
Even if it didn’t get used it was still an entertaining video. There is only so much you can do with JB Weld and a bubble gum weld somebody else attempted to use.
It looks like the previous repair attempt was done with a spool gun and no thought was given to keeping alignment, not just on the mating surface but of the bores.
First guy ruined that thing. It was a valiant effort!
It should work Isaac Thats a Ford Transfer case there's a gasket anyway Could silicone it too .
I have fixed transmission cases with JB Weld if the crack /hole is not structural. They have lasted for years.
I have found if you use the gas ax to burn the oil out with the oxygen cutting lever depressed not trying to heat the part up gust burn oil off it works well to clean up cast aluminum
A difficult repair at best nevermind it's second go at being repaired, cast aluminum never welds well and there's no guarantee that it will be successful, still an excellent example of the challenges this type of repair offers
With aluminium it is possible to heat it up so hard soap burns on its surface then quench it. This will remove all the work/age hardening the aluminium has received.
Also during this heating process it will show up if there is any oil trapped in the aluminium as it bubbles out.
👍if you can't fix it, it ain't broken
At first when you put that aluminum in front of the heater, I thought you would have tried to trick us into thinking it melted from getting to hot. lol It was a good effort in trying to fix it though.
Welding, Aluminium Crankcases, Gear Boxes etc can be a pain ???
The primary work in my shop was previously Repairing Aluminium Casings.
The jobs that look like would be a absolute pain actually went really well.
Where as Cases that should be fairly straightforward were absolute Nightmare.
Unfortunately, with some jobs I had to simply give up and hand the part back to the customer without completing the Repair ??
It's not a great feeling to simply give up from the sake of failing ???
But, some Cases were totally un-repairable no matter how much effort I put in.
the master of disaster at work that was a mess
It will be interesting for us also ;)
I'm thinking the original repair was with one of those weld sticks and an propane torche you see at the the county fair booth. They probable have a use but not in this case.
Did you ever get your Dynasty fixed, or are you still on an alternate machine? Just curious how extensive the problem was, if it's fixed.
Never got it fixed. Considered sending the circuit board to a friend who might be able to repair it. hadnt moved forward with that either. 😕😕😕
cast aluminum is tough to weld, it was completed with the best skill set!
The previous welder welds by the saying, "The bigger the glob, the better the job." Well, not in this case.
no pun intended
I’m a home gamer and I’m going to use that quote !!!😂🎉
Atleast it was an interesting learning experience.
If it was me doing it would have just JB welded it feom the first break for a "cold" weld, if it holds oil keep trucking.
The first job was a good example in epic porosity.
Looked like they try fixing it with some of that low temp aluminium brazing rods.
Great work! I am still wondering why you're not using auto darkening helmet!
My hood does have an auto darkening lens. I use the flip hood version for the grinding shield aspect of it.
MM77 Approved 👍🏼👍🏼
I agree. Should have been melted down. That said I have had “MINIMAL” success in the past by taking the support ribs from one side of the case and building matching ribs on the other side especially around the bolt holes. Then building up the low spots a filing them down as I went along. As I said minimal success. Good luck
Is there a certain temperature you need to get the casting to and maintain at while adding weld? How do you know if setting it in front of the heater is adequate or not or to hot?
Hi Isaac! Excellent work considering the existing damage.
if you weren't able to bend that housing back into alignment, would lapping the mating surface would have worked?
Great point, not sure
Looks like aluminum mig weld, but the had it positive lead instead of negative feed. And not enough shielding gas.
A replacement case would be cheaper than your time although it's a common failure so maybe there's no stock anywhere? Either way your welds are certainly 10000% better so at least it has a chance.