J-B Weld Always 'Works' part 1

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J-B Weld Always 'Works' part 1It may not work as 'well' as other repair methods---but it's wholly cheaper and faster. It sticks to almost anything, giving the impression that it 'works'.That's the critical element, these days. How 'well' something 'works', is simply a matter of personal opinion. If you think something 'works'---then it does. Mind over matter. Positive thoughts, positive reinforcement = Good Karma.The East Indian truck owner of this CAT 475 aluminum cover told me so:"It works, but DOT sez it's still leaking too much."  (Cal. DOT/CHP is highly fussy on oil, air, water, fuel leaks, any form of cracking (on a red tag job-I was once told to repair mud cracks on a logging truck!), tire condition, and brake adjustment, generating tens of millions of dollars in fines to feed themselves.)The casting boss piece wasn't even bonded to the casting---which really indicates that MORE J-B Weld.....lots more, goobered all over, while chanting mantras---would be the next logical step--any J-B Weld expert will tell us.This repair is an example of:-avoiding weld-induced heat cracking in a restrained, delicate casting-establishing a flush to slightly below flush condition of the gasket recess surface to the adjacentsame surfaces. IOW--studying how this part is designed to limit gasket compression andcasting distortion, with those little raised stops on the casting bosses.-not creating melt into the gasket groove areaThis is not an example of making pretty, 'wow' weld beads. Sometimes other things have priority--such as not cracking those center webs.With customer present, I checked the flatness of the entire part, plus the height of the broken boss.(Each casting boss and other areas of this cover have raised stops--acting as contact points to limitthe amount of gasket compression and help keep this cover flat.)The broken boss and stop was slightly higher than the rest of the casting, as shown-above.  Finished it needs to be the same relative height or a tad less--to prevent other bosses from breaking during tightening. This breakage occurred due to mechanic incompetence. Repeatedly mention to the customer the use of new gasket and following the CAT recommended torque and torquing sequence---which is ignored. (That's to be expected, considering the party I'm dealing with. I know my place in the scheme of things.)Soften the goober with propane torch, scrape off, wire wheel, abrasive points.Gently polish areas of the break with 3M abrasive pad, then keep checking with steel straight edge for relative height to the adjacent bosses, getting the boss and stop height down to flush, below:Heat transferred from the welding will expand this part of the casting and can try to crack those transverse, cast webs. A uniform pre-heat, is guarantee to warp this casting. To reduce the possibility of this occurring I decide to:-get in, get some fusion, wetting and welding-as quick as possible-then stop-cool down with water spray bottle, blow-dry with air and do a little more welding, listening for any'clink' sounds of cracking. [I fully understand that this fast, localized cooling to remove heat expansion/contraction-- prior to causing subsequent damage----is a practice forbidden by resident experts and metallurgists. In practice, for restrained castings this does work, especially when the casting is making heat expansion/contraction cracking. I've used this sucessfully on cast iron repairs, as well. A uniform, high, controlled pre-heat, will still not control the amount of heat expansion and subsequent contraction occurring from welding. Peening is an attempt to minimize these inherent weld bead expansion/contraction cycles created during repair welding.]It is a permanent mold, high quality casting, with almost no porosity--which surprised me. CAT does make/use rather high end quality parts, most of the time. After creating a flush condition, tacked up both inside and outside. Weld and cool repeatedly, doing the inside first. Ran the beads up the sides of the groove wall, then stopped. Picture below shows this stop on the top of the boss in RED CIRCLE. Continued in J-B Weld Always 'Works' part 2--below......Blackbird
Reply:J-B Weld Always 'Works' part 2Weld the outside, looking for edge wet-out, then add more bead for strength. Draw file the gasket flangeweld tops-flush. Setting straight edge across adjacent flange and boss stops, repair area was .010 below flush.Blackbird
Reply:Great write up, and pics. Too bad it will never work.......And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Dave powelson - You the guru!  Teaching us a better way...
Reply:Dave, I know I'm getting a little off-topic here, but on a subject I don't think can be stressed enough, and I wanted to bring this up in a thread you'd be sure to see it.  Many many years ago, maybe even before your time, not sure if it was before my time, just keep racking my brains and I just can't remember, there was a father/son team, over in Woodland, not far from you, known nationwide for their ability working on fuel tankers .....   These guys were the EXPERTS,,,,,    nobody better,    Trucks, trailers, train cars, you name it, they were coming from all over the country, straight to these guys, they could fix anything. ........  And nobody knew more than them about working with tanks full of volatile gases .......... they blew themselves up...................
Reply:Denrep:1-I'm not a guru. I've learned plenty, since joining this forum. I don't know it all--IMHO---nobody does, nobody can, nobody ever will.2-I present various projects, to show how I approached them, with some explanation as to 'how' & 'why'--in the hope, that maybe a little bit of this, may be of use to some folks. In every endeavor, there often is more than one 'right' way to approach things. A few people have open minds regarding this---most do not.mark8310:Apparently your off-topic post, was referring to some of my posts regarding tank repair.I'm aware that tank work is hazardous. I think, I'm 'slightly' aware of procedures to mitigate the risks.So the guys you mentioned, blew themselves up.IOW--they made a mistake or series of them--probably a series of errors. Life is full of risks--it's how we manage them--that counts.Bottom of a fast aileron roll--Lancair Legacy--250 mph; 5-5-08.Blackbird
Reply:Originally Posted by dave powelsonmark8310:Apparently your off-topic post, was referring to some of my posts regarding tank repair.I'm aware that tank work is hazardous. I think, I'm 'slightly' aware of procedures to mitigate the risks.So the guys you mentioned, blew themselves up.IOW--they made a mistake or series of them--probably a series of errors. Life is full of risks--it's how we manage them--that counts.
Reply:Originally Posted by mark8310I agree with you 100%, Dave, I have done more than a few "tank" jobs myself, proceedures almost identical to what you've posted previously.  I only brought it up, curious if you might have known the people I was talking about.  This would have probably happened back in the 1970's or earlier ......
Reply:Very informative Dave!Keep posting, I like your approach / reasoning for a fix like this.Miller Thunderbolt 225Millermatic 130 XPLincoln HD 100 Forney C-5bt Arc welderPlasma Cutter Gianteach Cut40ACent Machinery Bandsaw Cent Machinery 16Speed Drill PressChicago Electric 130amp tig/90 ArcHobart 190 Mig spoolgun ready
Reply:Originally Posted by STwelderVery informative Dave!Keep posting, I like your approach / reasoning for a fix like this.
Reply:Newbie question: What is peening?Very cool repair!
Reply:http://dictionary.reference.com/ American Heritage Dictionarypeenn.   The end of a hammerhead opposite the flat striking surface, often wedge-shaped or ball-shaped and used for chipping, indenting, and metalworking. tr.v.   peened, peen·ing, peens To hammer, bend, or shape with a peen. [Probably of Scandinavian origin.]  (Download Now or Buy the Book) The American Heritage® Dictionary of the English Language, Fourth EditionCopyright © 2006 by Houghton Mifflin Company.Published by Houghton Mifflin Company. All rights reserved. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~In the context of this discussion peening is used as a method of  relieving heat stress in the metal.  There is a surprisingly good description of this process in the controversial Wikipedia:  http://en.wikipedia.org/wiki/Peening -MondoPS: an even better discussion:  http://www.aws.org/wj/sept01/cullison.htmlLast edited by Mondo; 05-13-2008 at 11:12 AM.Reason: Add more informationMember, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:I have seen an oxygen bottle go like a rocket after falling over and loosing its valve,  made it two blocks!!!