Silicon Bronze TIG Brazing

hey Jody here today I'm doing a little take brazing and experimenting with pulse settings trying to dial in some dead simple no-brainer settings that pretty much work on everything for doing a little silicon bronze fill it or overlay or something like that so before we get into it let me tell you a quick story on how I first learned of silicon bronze and why I like it I was moonlighting at a sheet metal fab shop and guy brings me a hydraulic line off of his forklift that it's sprung a little small leak so he hands me a silicon bronze rod and he says hey clean this up and fill this in seal the leak so I cleaned it up nice and shiny wipe it down with acetone ran a bead around the thick area before it got before it was thin you know and then and then let it cool and then ran a bead on the inside of that ring and then on the inside of that ring until I finally closed this whole thing up and there even though it was paper-thin I never didn't even blow through it because of the difference in the melt points of the two of the two metals I was able to just flow go pass after pass until I joined it sealed up the leak it looked really nice and now I have a nice little wear pad there when he put it back on the forklift it would be years and years for that thing could ever wear through I don't know if he ever if he put a wear pad on it or a piece of rubber or what that wasn't my concern at the time but I just thought man that worked great that is a really slick rod to have around so since then I've used it for all kinds of things you see me you know on this channel you've seen me use it for all kinds of things I'll show some of them in this video it's time to get started too much talky let's do it alright this is the little project where I'm gonna try to dial in pulse settings using lay wire and it's just 14 gauge hot rolled steel outside corner joints but not everybody's interested in pulse not everybody has pulse settings so I thought I would do this little mock-up here of what I talked about in the introduction this is a worn area that I made with a grinder and you can see where it got all blue because I thinned it out real good like I bet it's only about 20,000 thick or so half a millimeter thick there in the blue spot where its thinnest now it could be even thinner than that and silicon bronze can still work on it without blowing through because of the large difference in melt point between silicon bronze and deal it's quite a lot is what I'm doing here is I'm just leaving the wire in the puddle because I've got a nice clean surface that's oxide free and I'm running a bead out there with that nice argon shield I'm running a bead on the thick part so then I have something to direct the arc onto from there on out and no matter how thin it is usually you can make something happen here without making a hole making things worse you do need to taper off really slowly on the amperage err you can leave a crater I fish hole whatever in the case of a hydraulic line you don't definitely don't want that you'll be a leak so I'm leaving the wire in the puddle that occasionally it might come out just put it back in there and as long as I've got a nice clean surface nice clean metal no mill scale no no oxides no heat tint it flows like honey with that nice argon shield this is a number 12 Furyk cup here it's providing a nice big blanket or argon preventing oxidation and that makes it flow really nice so now that I've got a little barrier there where the thickest part was I'm gonna let it cool and I'm gonna wire brush it as clean as I can get it I'm gonna give this a few minutes to cool down you could speed cool it a little bit with compressed air or something like that but it's probably best just to let it cool naturally now here you can really see the braze metal just wetting into the steel base metal and I'm focusing the arc on the on the previous silicon bronze bead and that's especially important if you're doing something really paper-thin once you get that first bead in there you want to focus the arc on the silicon bronze filler metal and you don't ever want to get that arc ahead too much you want to keep the arc over filler metal and keep adding filler and move it over because remember this is brazing you're not you're not wanting to melt the base metal at all if you can help it and in some cases like a hydraulic line it might be paper thin you're gonna really want to keep your arc over the filler metal over the silicon bronze and keep it added to the puddle frequently so I'm just working my way in and letting it cool in there actually the most time-consuming thing is just letting it cool but queen passes now you can get it you can rush it you don't have to let it cool as much as I am here but it really flows a lot better and there's a lot less oxides floating around in the puddle if you do let it cool quite often in quite a lot you don't have to let it cool to where it's cool to the touch or anything but it won't hurt to do that now I'm going to speed things up a little bit because it's really just more of the same going forward here bead after bead after bead just being patient getting it wire brush nice and clean tapering off nice and slow each bead yr brushing in between every bead every pass you can see I'm even even with me letting it cool I'm getting a little bit of layer of scum here and there but at this point most of this is going to be sanded off anyway well that will be that and once you've got enough once you're confident you've got enough on there you might even just leave it as is but if it's if it's going on some kind of a bracket or a brace or something or a hose clamp you know might have to do a little sanding in which case I would not take it all off I'd still leave a little bit of reinforcement there and that's it all right this is the project I have today it's hot rolled steel 14 gauge so I'm gonna have to do a little cleaning on this first thing to make the silicon bronze flow like it needs to flow I just want to clean it back about I don't know an eighth of an inch from the edge should be enough both sides and the edge this is a plasma cut piece so the edges will have that plasma cut dross on them and that's oxide and we don't want that so for fitting this thing I've got this new product called the mag tab jumbo I'm taking it apart here just to use the swivel pad portion of it but for a little outside corners and things like this this is kind of a handy little thing to have too if you're working by yourself you don't want to get a big clamp out you know all you need to do is hold it just long enough to get a tack on it this can be a really handy thing so that that's working pretty good I've got a corner to corner fit up now and all I need to do is pop a quick tackle on there and try to keep everything even let's do that try to make my tax a little bit smaller than the final final bead but that doesn't always happen and so when you go over tax that are too big you just don't add filler while you're going over them alright the pulse settings that I wound up with today are one pulse per second with 30% background and this machine is fixed to 50% pulse on time and I set up a scrap piece here or a coupon I should say of cold-rolled and I cleaned it pretty good wiped it with acetone after I sanded the edges and everything so I want to get the settings down before I before I dwell the actual part and also kind of get my camera settings down try to get it where you can see something where this thing is is instructive as possible so this is what I'm doing I'm leaving the wire in the puddle that's called lay wire technique I've got this if you're a ceramic 12 on there providing a nice big Shield of argon you can see where the cup is there's no discoloration that discolorations only where it's creeping behind as that argon passes over the heated area that is an indication of really good shielding there and it helps a lot on braze material like this on silicon bronze to make it flow nice at a lower amperage so that seemed to be okay no real complaints there I'm become I'm running about 25 to 30 cfh with about a three-quarter inch stick out and the only reason I'm using that long of a stick out is just to help the camera see in there to see the puddle so everybody can see what I'm seeing hopefully I laid a big chunk of aluminum here right next to the well to kind of keep it from teetering but also to kind of trap argon when you're doing an outside corner the argon flow kind of can split and you won't get as good of shielding so putting something like that right there can help just a little bit [Music] so far so good I'm wishing I had been a little more thorough with my cleaning here though I cleaned the edge and cleaned about 8 of an inch back I should have cleaned a little bit more and just a little bit more I can tell pulling a little bit of oxide in the puddle and maybe that's just because it's thin it's only 14 gauge or the little gap I may be pulling some oxide from the backside in which case you know there's not much I can do about it all right there's several more corners to do on here but they're all going to look pretty much the same so there's no point in showing all of them what I will show though is some previous clips of some different tasks that I've done using silicon bronze so one of them was a dead blow hammer that I built and I surfaced the ends with silicon bronze and then sanded and polished them so now I have AB hammer full of bb's for the deadblow aspect of it but then some nice silicon bronze faces on here and that kind of comes in handy for bumping around the the key Chuck on my welding lathe here and there it's just a it's kind of more like a conversation piece than anything but you could easily be very functional if you want to if you want a bronze face hammer and don't want to buy one you can just overlay the end of any hammer with this stuff and like I said this in this case I've got it full of bb's and it's like a dead blow hammer which is pretty useful I put this bone here this threaded bone with a cap on the end and then I again I filled it filled it up about 3/4 full of just regular old bb's and made a nice hammer I just colored it with heat and wiped it down real good with wd-40 while it was hot so so far in the shop you know just might have a speck or two of rust on it but came out nice I got this cart from CT fab super nice welding car this is 14 gauge cold rolled with dimple die punches for added rigidity and it's it's it's outside corners joints and I put the whole thing together using silicon bronze just because I kind of wanted the practice and because I didn't want it to warp and it didn't need to be that strong here's a real good example of coming in coming in over the top with silicon bronze lots of applications where you you know it does need to be an application you don't need a joint to be as strong as a welded joint and this cart was a good example of that I put together this cube where I I got some practice in on welding the first pass with TIG wire weld wire with er 70 and then after those were all done I wire wheeled the oxidation off real good because you want to do that if you're going to come over on top of a weld with braze you want to get rid of all the oxidation and then I filled those those fill its in with a pretty big like a 1/8 rod of silicon bronze and I just wanted to fill him in because I figured I would probably sand them off or whatever just there's a lot of lot of area to fill in there and again using the same cup did this a good while back and shielding was really good and shielding is important for TIG brazing this one became a sort of a paperweight for my son but I went ahead and put together another one for myself because it makes such a handy prop to have on the bench just to prop my poem on for for welding other stuff so that's what I'm gonna use this die for here it was going to be a set of dice but we wound up just making one and I thought well might as well put it together and have a box at a different height to prop on four different height stuff not to mention it was just a fun little job to do before I go here just to clarify if there's any students watching this you'll need to know this you will for future use you may not think you will you will the difference between soldering brazing and welding they break them off at temperatures basically so depending on what textbook you consult give or take a degree or two soldering is under 840 degrees Fahrenheit but not melting the base metal and then brazing is 840 degrees and above but not melting the base metal and then welding is melting the base metal okay so that's those are the that's the basic of it and the concept in brazing and soldering is that metal will flow on an oxide free surface if you've ever over heated copper joint or something with a torch and just scalding it and got that got that layer of oxide on there you know it it won't take solder anymore now you have to stop clean re clean reflux things like that Mittal then it removes that layer of oxide and then the solder will flow again same thing with with silver brazing same thing with TIG brazing except for the fact you don't have flux with TIG brazing so you've got to have the metal extra clean clean bright metal no mill scale and you want to have a really good argon shield and you don't want to introduce oxides into the puddle by coming in and out of the puddle with the tip of that rod so that's why that's why most of what I show today is I'm using lay wire that's what I'm trying to figure out is a good setting that I can just leave the wire in there and not risk adding oxides to that puddle to make it it makes it sluggish when there's oxides in there so you want an oxide free surface you want an oxide free rod you want to clean that rod off you don't want to clean it with anything that will embed grit into it or leave a deposit so wipe it off really good with acetone sometimes you leave that rod out it is it's got an oxidized surface on it you know it's like a dull film if you look at it real close it's almost like a little layer of corrosion you know like copper the patina that you get on copper and stuff that's oxides so you want to clean that off you don't want you don't want oxides there they do not help with brazing so you don't have flux to clean the oxide you only all you've got is arc and argon so that brings me to this you know alternating current works great for for silicon bronze as well I use it all the time on aluminum bronze because of that aluminum content in the filler metal but you generally don't need alternating current with silicon bronze you can use a nice smooth arc as long as you have a nice a nice argon shield and you saw me using that 12 cup that provides a nice argon shield so that's it brazing needs a clean surface if you don't have flux you need argon to keep it oxide free so all I got today see you next time you

Channel: weldingtipsandtricks

Views: 168,269

Rating: 4.9576335 out of 5

Keywords: tig brazing techniques, tig brazing, silicon bronze, uses for silicon bronze, silicon bronze tig rod, tig welding with silicon bronze, how to tig braze

Id: mTw1-yag3IY

Length: 15min 12sec (912 seconds)

Published: Mon Jan 07 2019