0:00:00.000,0:00:00.951 Welcome to Weld.com. 0:00:00.951,0:00:03.908 last time we did some brazing, never. 0:00:03.908,0:00:05.544 Let's do some brazing today. 0:00:05.544,0:00:08.423 You wanna? 0:00:08.423,0:00:13.716 I've got a product over here,[br]it's by a local company, local vendor. 0:00:13.716,0:00:21.186 It's called, LF BFC and it is a low[br]fuming bronze type application here. 0:00:21.186,0:00:22.770 It's got the flux on the outside. 0:00:22.770,0:00:26.788 I like using this stuff for[br]general repair, but 0:00:26.788,0:00:30.414 I wanna demonstrate just some technique. 0:00:30.414,0:00:34.556 When I tack these up I wanna[br]use quite a bit of gap. 0:00:34.556,0:00:41.128 And the reason I wanna do that is because[br]I wanna show you some heat sensitive. 0:00:41.128,0:00:43.865 If I just poured the heat in here and[br]stuck this rod, 0:00:43.865,0:00:48.080 then I expect this to just fall through[br]the backside, we don't wanna do that. 0:00:48.080,0:00:52.314 So I wanna do this exercise of[br]actually controlling our heat. 0:00:52.314,0:00:59.832 I do want the penetration,[br]I want this to show on the backside and 0:00:59.832,0:01:04.020 I also wanna fill this on the front. 0:01:04.020,0:01:07.920 It's an outside corner joint but[br]it's gonna have gap in it, so 0:01:07.920,0:01:11.745 I wanna fill this up enough that[br]it's nice and round up on top or 0:01:11.745,0:01:14.045 at least fused along the edges here. 0:01:14.045,0:01:19.497 So let me get some gear on and[br]we'll, we'll put some space in this. 0:01:19.497,0:01:25.716 When I tack these, I'll probably light the[br]torch and put a big old dot out here and 0:01:25.716,0:01:30.014 bring it out a little bit and[br]then I'll get a magnet, and 0:01:30.014,0:01:34.248 I'll have this held up here[br]where it's got some gaps. 0:01:34.248,0:01:36.008 I'll fuse these parts together, but 0:01:36.008,0:01:38.649 I do wanna show probably about[br]an eighth of an inch of gap. 0:01:38.649,0:01:41.298 I know that sounds big for 316 plate but 0:01:41.298,0:01:45.612 again I'm trying to show a couple[br]of exercises here of control, and 0:01:45.612,0:01:50.175 how this stuff flows and everything,[br]and how to manipulate the torch. 0:01:50.175,0:01:51.698 So old school stuff. 0:01:51.698,0:01:54.880 I like doing brazen. 0:01:54.880,0:01:57.978 I do a lot of repairs on[br]various equipment and 0:01:57.978,0:02:01.598 one of the first things[br]that I consider is brazing. 0:02:01.598,0:02:06.190 I always do for some reason probably[br]because I just like it so much. 0:02:06.190,0:02:08.815 So, let me get my stuff on,[br]I'll be right back. 0:02:08.815,0:02:09.550 Welcome back. 0:02:09.550,0:02:15.952 I have these tacked,[br]I have 316 plate and I went ahead and 0:02:15.952,0:02:20.702 put 332 gap, maybe a little open there. 0:02:20.702,0:02:25.122 I don't think that's an eighth of an inch,[br]I'm gonna call that 332 and 0:02:25.122,0:02:28.430 it's pretty good size gap if[br]you can see that on camera. 0:02:28.430,0:02:34.609 So the attempt here is,[br]I've already have some glass showing here, 0:02:34.609,0:02:38.557 and this glass is an end[br]product of the flux. 0:02:38.557,0:02:42.332 Could we use a bare wire and powder flux? 0:02:42.332,0:02:43.320 Sure. 0:02:43.320,0:02:46.362 Maybe we can demonstrate[br]that in another video. 0:02:46.362,0:02:50.922 This one, I wanna use this product here,[br]which is the low fuming bronze product, 0:02:50.922,0:02:54.440 has the flux already on the wire,[br]it's just real convenient. 0:02:54.440,0:02:58.311 So I'm gonna start out and[br]I'm gonna start heating this up. 0:02:58.311,0:03:02.583 So what's the, there's brazing and[br]there's welding. 0:03:02.583,0:03:03.749 So what's going on here? 0:03:03.749,0:03:06.550 How do we make a bond with brazing? 0:03:06.550,0:03:10.839 Brazing is generally 840 degrees and 0:03:10.839,0:03:15.892 above but[br]not melting the parent metal, Okay? 0:03:15.892,0:03:22.170 So the filler wire is gonna[br]melt at around 840 and 0:03:22.170,0:03:28.596 it's gonna bond by what we[br]call a capillary action. 0:03:28.596,0:03:31.683 I have cleaned these plates,[br]they're rusty down here, but 0:03:31.683,0:03:33.812 they're clean down to pure white metal. 0:03:33.812,0:03:37.188 The flux will pre-clean the surface and 0:03:37.188,0:03:42.757 by this capillary action it will[br]make a bond into the parent metal. 0:03:42.757,0:03:46.362 It wets into the parent metal and[br]it sticks and bonds to it. 0:03:46.362,0:03:50.184 Soldering is 840 degrees and below, so 0:03:50.184,0:03:56.038 we start talking about these[br]concepts of brazing and soldering. 0:03:56.038,0:03:58.207 What can you do with them and the alloys? 0:03:58.207,0:04:01.401 It gets kind of interesting when you[br]actually look, see what's in them and 0:04:01.401,0:04:04.553 how they melt, and how they bond, and[br]what you can actually do with them. 0:04:04.553,0:04:06.237 And then again how strong they are. 0:04:06.237,0:04:11.085 That's what's amazing to me is how[br]strong this stuff actually is. 0:04:11.085,0:04:14.372 So let me light a torch here and[br]I'll be right back. 0:04:14.372,0:04:19.160 I may put my dark shield on because some[br]of you ding me pretty hard on not wearing 0:04:19.160,0:04:20.126 a dark shield. 0:04:20.126,0:04:24.526 When I did the brass tree showing[br]how to manipulate this stuff, so 0:04:24.526,0:04:26.614 I may wear my dark shield here. 0:04:26.614,0:04:27.456 Be right back. 0:04:38.740,0:04:41.650 I'm using an OTT tip, and 0:04:41.650,0:04:46.412 my oxygen pressure is set about 4 pounds, 0:04:46.412,0:04:52.251 my acetylene pressure is[br]set about 3 pounds 3 PSI. 0:04:52.251,0:04:59.868 My torch angle is about[br]2030 degrees point or 0:04:59.868,0:05:04.892 20 degrees pointed forward. 0:05:04.892,0:05:12.470 And you'll notice that I'm[br]taking it out of the pool here. 0:05:12.470,0:05:18.871 This is liquid solid. 0:05:18.871,0:05:24.400 So and the reason I'm doing[br]that is because again, 0:05:24.400,0:05:30.826 as I said when we did the intro,[br]if I just left this in there, 0:05:30.826,0:05:38.306 it would probably fall through to[br]the backside and kinda make a mess. 0:05:38.306,0:05:45.838 It'd be too much on the backside, 0:05:45.838,0:05:51.292 I'm trying to get this to 0:05:51.292,0:05:56.240 round, up slightly. 0:05:56.240,0:06:00.616 So I wanna fill it in, but[br]I don't want it to drip through. 0:06:00.616,0:06:06.043 I want it to show 0:06:06.043,0:06:11.470 on the back side 0:06:11.470,0:06:18.150 just like amperage 0:06:18.150,0:06:23.164 and voltage. 0:06:23.164,0:06:26.074 When you're wire feed welding,[br]you can turn things up. 0:06:26.074,0:06:27.553 How about stick welding? 0:06:27.553,0:06:30.626 Could I use a bigger size wire? 0:06:30.626,0:06:33.440 And a bigger tip and more pressure? 0:06:33.440,0:06:33.940 Sure. 0:06:38.010,0:06:42.790 I would probably do these manipulations 0:06:42.790,0:06:48.139 a little quicker, and[br]this is a little slow. 0:06:48.139,0:06:51.690 But again,[br]I'm trying to show this technique. 0:07:21.833,0:07:24.991 I remember when I first started welding, 0:07:24.991,0:07:28.877 very first thing we did[br]was oxy acetylene welding. 0:07:28.877,0:07:33.436 Learn how to manipulate the pool and[br]the filler wire. 0:07:40.416,0:07:45.808 I have laid the filler 0:07:45.808,0:07:51.204 wire a little lower. 0:07:51.204,0:07:53.713 Now every time I introduce the torch, 0:07:53.713,0:07:58.193 it may look like I'm melting the wire[br]with the flame, and I'm not. 0:07:58.193,0:08:06.106 I'm creating a weld pool first. 0:08:06.106,0:08:09.144 I'm leaving it right on the leading edge. 0:08:09.144,0:08:11.606 I teach this class in my program. 0:08:11.606,0:08:16.550 I teach oxyacetylene welding,[br]brazing silver soldering. 0:08:16.550,0:08:19.968 Right alongside the introduction[br]to tig welding. 0:08:19.968,0:08:25.065 If you think about it,[br]it's the exact same hand 0:08:25.065,0:08:30.301 eye coordination,[br]filler wire, heat source. 0:08:30.301,0:08:35.305 I think I wanna leave 0:08:35.305,0:08:40.013 this open at the end 0:08:40.013,0:08:45.015 just to show you what 0:08:45.015,0:08:50.617 the original gap was. 0:08:50.617,0:08:59.560 I'm gonna do a little remelt here. 0:08:59.560,0:09:04.688 Saw a couple of bug holes right on[br]the surface that I didn't like, 0:09:04.688,0:09:08.520 so I went ahead and[br]just remelted them slightly. 0:09:08.520,0:09:10.659 Could I remelt this whole thing and[br]reshape it? 0:09:10.659,0:09:16.805 Sure, but then I take a chance of[br]all of it dripping through again. 0:09:16.805,0:09:21.329 I'm gonna go quench this off and[br]I'll probably leave it before I buff 0:09:21.329,0:09:25.076 it off with the wire wheel or[br]whatever we do to clean it up. 0:09:25.076,0:09:28.385 So let me go quench this off[br]because it's saturated with heat. 0:09:28.385,0:09:31.516 Be right back. 0:09:31.516,0:09:32.384 Welcome back. 0:09:32.384,0:09:33.062 I finished this part. 0:09:33.062,0:09:38.526 I went over and quenched it and I very[br]lightly touched it with a wire wheel 0:09:38.526,0:09:44.283 just to get this excess of flux and[br]glass off, and I did the same on the back. 0:09:44.283,0:09:45.599 We could have gone a little bit hotter. 0:09:45.599,0:09:49.750 We're showing that we melted[br]some on the backside. 0:09:49.750,0:09:54.691 We didn't get through as much as I[br]would have liked for a demonstration, 0:09:54.691,0:09:57.284 but I'm pretty sure you can see this. 0:09:57.284,0:10:01.331 We've gone just a little bit more in heat[br]and let it fall through a little bit, 0:10:01.331,0:10:03.339 it would have bonded on the backside. 0:10:03.339,0:10:08.978 What came through on the back was[br]it really looks like a glass. 0:10:08.978,0:10:13.206 And so, I mean, when it solidifies,[br]you can knock it off, 0:10:13.206,0:10:16.514 you can chip it off,[br]I hit it with a wire wheel. 0:10:16.514,0:10:21.100 Again, we could have gone a little hotter,[br]maybe a little more aggressive. 0:10:21.100,0:10:25.021 I just wanted to show this[br]technique of filling this thing up. 0:10:25.021,0:10:28.627 You can see some dark[br]discoloration spots in here. 0:10:28.627,0:10:33.619 I didn't hit this with the wire wheel[br]because this is soft enough that it will 0:10:33.619,0:10:35.968 re-arrange the patterns in here. 0:10:35.968,0:10:39.710 I've left these ripple patterns down[br]here at the bottom of this part. 0:10:39.710,0:10:43.707 I went ahead and hit it with[br]a flapper wheel with a 40 grit. 0:10:43.707,0:10:47.684 I believe it was just to blend this and[br]sand this over. 0:10:47.684,0:10:52.021 I mean, this thing looks pretty nice,[br]very slight bug holes in it, 0:10:52.021,0:10:53.630 which is kind of normal. 0:10:53.630,0:10:54.884 You can go back and melt those out. 0:10:54.884,0:10:59.507 You could sand this and polish this off,[br]and it just look, it looks like gold, 0:10:59.507,0:11:00.292 It's cool. 0:11:00.292,0:11:05.281 So we've done some projects where[br]we're putting some stuff together and 0:11:05.281,0:11:07.542 we get that color differential. 0:11:07.542,0:11:10.613 You can play around with this and[br]weld some, 0:11:10.613,0:11:14.432 some other types of material[br]other than carbon steel. 0:11:14.432,0:11:17.721 I have my students[br]memorize chemical symbols, 0:11:17.721,0:11:20.192 all kinds of other technical data. 0:11:20.192,0:11:23.123 They think they come in here and they just[br]get to strike an ARC, and that's not. 0:11:23.123,0:11:27.401 So we need to know some things,[br]and we need to know about 0:11:27.401,0:11:32.062 35 elements of the periodic table for[br]chemical symbols. 0:11:32.062,0:11:35.390 And right here they are technical data. 0:11:35.390,0:11:42.558 We've got a melt point of about[br]1620 Fahrenheit, 882 Celsius. 0:11:42.558,0:11:45.856 Again, I said brazing is 840 and[br]above, but 0:11:45.856,0:11:50.320 not to the melting point of carbon[br]steel that we were welding on. 0:11:50.320,0:11:53.716 So this says that the nominal,[br]let me back up. 0:11:53.716,0:11:59.348 It says to pre-clean the joint,[br]bevel heavy sections, preheat broadly, 0:11:59.348,0:12:03.924 then concentrate oxy fuel neutral[br]flame into the joint area, 0:12:03.924,0:12:08.412 melt some flux off the end of the rod so[br]it'll be activated and 0:12:08.412,0:12:11.411 it gets down in around the parent metal. 0:12:11.411,0:12:13.945 And then you can start[br]dipping the alloy and 0:12:13.945,0:12:16.703 melting the alloy like[br]we demonstrated here. 0:12:16.703,0:12:18.078 The technical data. 0:12:18.078,0:12:24.502 The nominal analysis says Cu 58%. 0:12:24.502,0:12:26.339 So what's Cu? 0:12:26.339,0:12:28.961 It's a chemical symbol for copper. 0:12:28.961,0:12:32.617 And Sn is 10.1%. 0:12:32.617,0:12:38.099 Mn is manganese, 0.040%. 0:12:38.099,0:12:42.793 Fe is ferrous iron, 0.75%. 0:12:42.793,0:12:49.037 Si is silicone, 0.1% with a Zn balance. 0:12:49.037,0:12:50.866 Zn is zinc. 0:12:50.866,0:12:54.352 So now you know what chemically[br]you're working with here, and 0:12:54.352,0:12:56.471 that is typical of all filler metals. 0:12:56.471,0:13:01.034 I don't care if you're looking[br]up a stainless electrode, 0:13:01.034,0:13:07.057 you're gonna be given the chrome,[br]the moly the nickel, the carbon content, 0:13:07.057,0:13:12.828 anything, it's all gonna come to you[br]in chemical symbols I have not read. 0:13:12.828,0:13:16.879 I can't remember looking up a technical[br]spec of something that hasn't, 0:13:16.879,0:13:19.309 whether it's a base metal or[br]a filler wire. 0:13:19.309,0:13:24.858 I can't remember looking it up,[br]having it spell out chromium, 0:13:24.858,0:13:29.604 or carbon, or nickel, or[br]molybdenum, or whatever. 0:13:29.604,0:13:34.185 Every one that I've ever read has been[br]given to me in a chemical symbol fashion. 0:13:34.185,0:13:36.608 So anyway, I hope this was fun. 0:13:36.608,0:13:40.120 We'll do some more brazing[br]demonstrations and we might do. 0:13:40.120,0:13:43.400 Hopefully, we can dream up a project[br]where we can braise it together. 0:13:43.400,0:13:48.259 I know in the past that we did[br]a brass tree and it was an exercise of 0:13:48.259,0:13:53.766 manipulating this wire, and[br]building this tree, and starting out and 0:13:53.766,0:13:58.445 going all over the place,[br]which is a really good exercise for 0:13:58.445,0:14:02.439 learning how to manipulate the torch and[br]the heat. 0:14:02.439,0:14:04.130 So I hope this helps. 0:14:04.130,0:14:06.240 Thanks for watching our videos. 0:14:06.240,0:14:09.427 Bob Moffett with Weld.com,[br]make sure you subscribe to the videos. 0:14:09.427,0:14:11.225 New videos come out every Monday. 0:14:11.225,0:14:19.250 Thank you.