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