How to fillet braze - From start to finish with Paul Brodie

hello i'm paul brody we're in my shop once again welcome mitch is behind the camera working his magic and we're going to do a little bit on on philip brazing i have a frame here that i've been working on and i think the first thing we should talk about is the size and the shape of the fillet it's dictated largely by the shape of the spiral roll this is a spiral roll or a cartridge roll and so if you look at the shape can you see how the roll if i put the roll in about halfway can you see how it conforms to that if you make it too small a spiral roll isn't going to work very well you're going to be en ending up using what i call i call this part the nose and you're going to wear that down and then this part won't get used it's glued right here can you see the glue there's the glue in between my thumbnails so you don't want to use that part there if you grind on that part this thing will unwind it'll fly apart not good so this is really the working part in between there in between my thumbs i taught frame building 101 for a number of years often often the students have a hard time having enough of the braise here and here so what i used to do is i had a spiral roll and this just mounted on a rod like that just pops off it's a 3 16 rod so after the student had done the philip braze we'd have a look and if if if there wasn't enough in there they'd have to add some more and so that was one of the spots where there was often a lack of of material and and this was the second spot as well getting in between the seat tube and the chainstay they often wouldn't have enough material there either so you need to get an ample ample radius in there it's hard to do that in one pass sometimes it's a lot easier to make a first pass and then get a second pass over that if you try and do it all in one pass sometimes what happens is you get an air hole so i was in the shop earlier this morning and i purposefully made a braise with an air hole or a big hole there and the hole goes all the way down doesn't just go halfway it goes all the way down so i'm going to show you how to take that out there is a technique i've got a tangy top tube it's uh it's an odd size it's an inch and three sixteenths but it's it's tank a ultimate super light mtb tubing there's there's a little label on it this is old stock this is back from 80s 90s something like that i don't think you can buy this anymore so we're going to use this i'm going to miter it i've got an inch and a half half od piece of 4130 and i'm gonna fill it braze that onto there okay see this piece hanging off if you use your fingers eventually you're going to get a cut always use a pair of pliers it's easy it's smarter [Music] got some 80 grit just gonna scuff it up a little bit it's too shiny for brazing what you're looking there it's micro polished you don't want to braise over top of that it'll probably work but if i was a piece of braised i'd rather hang on to that i just wanted to show you a couple things for us seeing as the frame is still in the park stand what i wanted to show you was that when you're braising you have to have to be able to move the frame with one hand so if i've got the torch and i'm brazing i am i am right handed so i hold the torch in my right hand i got the rod in my left and then when i want to move the frame i hold the rod like that and then i can move the frame if you don't do that now you've got a hot rod and you can burn yourself you put holes in clothing all sorts of stuff it can be dangerous so what you want to do is to have have the setting here so that you can move the frame with one hand and you also want to be able to rotate the frame so that's that way so if if this is too tight this clamp here i can move the frame this way but i can't move it like that so you want to have them set so that it's kind of equal in the tension between rotation and back and forth that's what i wanted to show you also when you're braising let's say i'm going to braise right here okay there's a vertical component and there's a horizontal component you have to think of you have to keep it in mind at all times so if i'm brazing right there i've got the angle of this tube and i've got the angle of this tube and if i go half way can you see how it it's it's not vertical if i go down to here now that's where i want if if i'm in if the frame is held right here now i can brace right here because that's the vertical component whoops pressing down a bit too much that's halfway and the horizontal component is right there that's level if you have it any other way and you're trying to braze there you are fighting gravity if that puddle gets too hot it's going to slump and then you have a problem so if i'm braising let's say i'm going to be brazing i want to braise right there so i've got the two components again that's the vertical component because if i extend the wall of the bottom bracket that's about halfway maybe up a little bit like that and the horizontal component is right there so i can braise so right there i can brace from here to here and then if i want to braise here i have to move the frame so as i go around i'm constantly moving the frame and if you don't move the frame i guess gravity is going to win i'll put my money on gravity got the flux it's type b paste flux i don't think you have to put a huge amount on just has to cover on our last bracing video i was showing uh the different kinds of of flames oxidizing carburizing and neutral but we didn't have a filter so now we have a good filter so mitch is going to use that and i'll show you all the different kinds of flames and and the shadow that's important so right now what i've got is a is a is a neutral flame if i increase the acetylene can you see there's a shadow there now okay that's the end of the cone right there and you see from here to here that's a shadow that shows there's an excess of acetylene in there so if i close down the acetylene that's my neutral flame as soon as the shadow's gone that's neutral flame if i want to make a smaller flame i close the oxygen that causes a shadow there as well and then i close down the acetylene so i can keep making smaller flames and if i'm silver soldering a water bottle boss on that's about how large the flame might be so now i'm going to go larger i open up the acetylene add oxygen that's my neutral flame i'll go one larger can you hear how it's starting to hiss okay sometimes if it hisses it means that it's just a large flame i'm gonna add oxygen now so watch the cone can you hear how the hiss gets larger and the cone gets a little sharper but if you first look at it you can't tell if that's an oxidizing flame or a neutral flame so i'm going to close down the oxygen there's the shadow now i close down the oxygen more let's see how large a flame i can get that's a pretty big flame so it's got a real hiss to it but it's not oxidizing so i'm going to come back and that's what i call a medium flame i'm going to show you something else too if i get a if i get a vernier okay this is a victor tip and if i take the size of the tip right about there and then i compare it it's about the same length so when i say use a medium flame that's about the size just a quarter inch back on the end of the tip that's my rule of thumb i'm going to nickel silver on this and normally i'd go straight to philip brazing but i'm going to let it cool because i want to show you something i'm going to aim it at the bottom bracket right about there and if i do that it'll heat up because this has to heat up the same time as the tube and there's a little tag a little sloppy i'll try i'll try and do better on the other side here maybe my flames oops hear that if you hear that that means that one tube got a little i'm gonna switch my flame down just a little bit it makes a difference okay here we go so i'm aiming it at the bottom bracket and there's my tack that was better so i'll get a little bit more heat now so i'm not holding the cone quite as close now maybe 5 8 of an inch away and you can see if you watch you can see it start to wick and i'm i'm not aiming the cone right at the corner on the bottom bracket a little bit because the bottom bracket's going to take a little bit more heat there we go when it just starts to flow that's when i add the rod i like this nickel silver it flows very nicely it really gets right into the corner if you only use the three thirty seconds rod you don't know for sure it's going it's wicking right into the joint [Music] okay in phillip brazing if you get the size and the shape of the fillet so that it fits the spiral roll nicely you have made your yourself a lot less work if you make the fillet larger a lot larger you haven't increased your workload by maybe a small a small percentage you've increased it by a huge percentage it's a lot more work and some students in frame building 101 had a lot of trouble in in in keeping it a certain size so one of the things i did or i showed them how to do is if you take a red felt pin and you mark where the fillet wants to go even though you're brazing and there's flux on and it's heated up you can still see this while you're braising so this is what i would do or show them how to do and this might be helpful for you i just draw a dotted line like that and then if you braise in between those lines that'll help if you go much larger than that that's a lot more work because because one of the things that that happens when you're using a spiral roll you need to find the center of the fillet and establish the center line if your fillet is so wide you don't really know where the center line is so that's a real disadvantage right from the start and in philip brazing you're playing in that zone of melting not not melting it's a it's a fine temperature range because you want the you want the bronze to melt fast and then you want to you want to take off the flame for a moment just to let it momentarily cool and then you add more bronze and what i do is i go back and forth i go on the the right side i do a little bit on the left side a little bit on the right side and that means that when i'm on one side the other side has a chance to cool just a little bit and that makes a difference so here we're going to start over here i'm going to start in the middle and and you'll notice how i'm usually holding the cone straight on and if i if i bring the flame in i'm melting the rod usually i'm not usually melting in the rods over here somewhere usually i've got the rod right under the cone the cone is the hottest part of the flame so i want you to notice things like angle of the cone and and the distance of the cone from where i'm melting it those are important things to notice so you see how i'm melting it and then i take take away the flame for a moment so i've done a little bit now i have to turn because i don't want to fight gravity so i like i said i'm doing a little bit on the right a little bit on the left but on the in the middle see in the middle i got to make sure that i get the heat in there too so that melts i don't want to get a hole in the middle and that can happen and we're going to show you how you fix that so i think you're noticing how often i have to turn it it's not like four times it's many times and the cone is basically melting that rod as you put more bronze on what you're doing is to build up a heat sink so sometimes you might find you have to make the torch a little harder towards the end of the brace in some situations like if you're putting on the chainstays for example because there's a huge heat sink around the down tube in the seat tube and it's sucking a lot of heat so that's where the torch has to be the hottest if you feel it brazing a frame when you're putting on the chainstays in the 40s and the 50s in england a lot of the frame builders a lot of the custom frame builders often use philip brazing because there was a move towards oversized tubes and there wasn't a lot of lugs at that point which were made for oversize and so that's why philip brazing often became pretty popular back then and and the war ended and and the women who were working in the factories and knew how to braise they basically lost their jobs when the men came home so a lot of the women got hired by the cycle manufacturers i think that's kind of a cool story i like bicycle history now we've almost come around here one more position yes [Music] okay we are going to work on this here this is just a practice tube i worked on this morning and there's the hole because often a student would get a hole in a frame and almost always i can show you where the holes would happen either the hole would be right right here or it would be in in here because those are the areas where you really have to build it up quite a bit and usually i could i could fix it some and there was a couple cases where we had to grind it out and then start again because the hole was so deep i couldn't do it but usually i could fix it i'm going to show you what what i did if you're going to melt a hole you need a fairly hot flame so you need a little bit of a hiss to it so i've got a little bit of a hiss and you want to hold it right on there and you circle around until it gets warm and then once it gets warm you have to put the cone down inside the hole that's the trick because you need to heat the bottom of the fillet and just circling around on the top might work might not holding the torch with two hands here and circling okay can you see how it's melting on the outside so you got to put the see how i've got the cone right there there you go filled in that's basically what you want to do when you get a hole you've got to heat it up enough so you can you can have the cone go inside the hole what i want to show you now see all this lumpiness i did all this lumpiness on purpose because i want to show you what to do so i don't need quite as big a flame so i start working on a high spot holding the torch with two hands and as soon as it melts see it melt i take the torch away and i go back if you leave the torch on there the whole thing will heat up and it'll droop i promise you it'll droop you can try it see what i'm doing just a little bit at a time you have to let it cool and then you can go again i'm smoothing it out i'm going to turn this a little bit see see i've got a see there's a hole there and sometimes you might have to add a little bit of rod but i'm going to try not to add rod and just see how smooth i can get it okay so if you look at it you use the side of the flame as the flashlight that's pretty smooth turn it a little bit that smoothed it all out that's what i would do i'd like to make you a sketch so i can show you what's going on in the file up process so if here's a tube and here's another tube here's the phillip rays sort of like that it's probably a little lumpier but let's say that's the phillip brace so the first step is to use the spiral roll and what the spiral roll does the first step is to do it is to make a centering groove so let me write that down so this is the centering groove like this what it does is it establishes the center more or less and it makes a smooth radius and the second step i call it edging out what you want to do is to take a little bit off a little bit more off a little bit more off you're edging out and then you go on to the steel if you see a whole bunch of sparks you're onto the steel that's not a good sign if you see a couple little random sparks that's not a problem what happens sometimes is that a student is going over over this bump and i've seen this happen there's often you've got the centering groove and then there's a bump and the student will use the spiral roll and go over this and you end up with an undercut this is the tube and this is a very bad thing to have happen because you have have decreased your wall thickness where you want it to be and that's why if you see sparks you're doing something wrong you want to edge out and then at the finals at the final part of the process when this radius comes down and matches the tube that's when you can go under the tube so stay away from the tube stay on the philip braze this is what makes the shape of the fillet you see how it's hard well it's firm anyway this is what makes the shape of the fillet when you switch over to the belt sander can you see how the belt sander is really flexible it's really hard to make a shape with this this wants to follow so this is really good for the smoothing and the polishing and one of the mistakes i've noticed on the students is they switch from the spoiler spiral roll to the belt sander too soon it's still lumpy they haven't made it smooth enough with a spiral roll and they're already polishing so each of them has its place but you have to do each step at its own pace and not switch too soon so let's go over and we'll do a little bit on the spiral roll what holds the roll is an arbor and that's the arbor there's a straight section and then there's a thread which is on a taper that's what holds it on and i think they're about i don't know three or four dollars that's the part number and the high ski high speed grinder i have is a makita they lost quite well i think this one was 196 dollars something like that and that's canadian and the spiral rolls come in a box like that and i buy i buy a box of 100 and it's a little over 200 bucks so about two bucks a roll a little bit more so we're going to do the first part i'm going to do a quadrant and that's normally what i do i normally do one quarter at a time then i go on to the next quarter and around the tube this is the centering groove so i want you to watch the motion of my hands i do a little bit and then i look because if i keep going i can't see underneath the spiral i have to take it off and see what i've done okay so just oh and and something else you can you can also listen for when i switch on the grinder it's got a certain sound and when i'm applying force and pressing down you can hear it you can you can tell how much force i'm putting on it a little bit by how the sound alters [Music] so that is my centering groove and you see how i'm i'm not just going like that i'd get a flat spot i'm following the ark that's what i'm trying to say i'm following the ark so now let's work on i'm going to work on this little bit right here and i'm going to edge out [Music] you can see how i've touched onto the steel a little bit but if i take my finger i can't feel any undercut there so that's okay so now i'll work on this part right here [Music] that's smooth so i'll do the same thing over here now [Music] so i think i'm going to do this side as well because then when i use the belt center i can show you how to belt sand right in the middle because there's a little little bit of a trick involved there so we're going to also do that side there [Music] [Music] after using the cartridge roll now i've got a shape and what i'm what i'm going to do is i'm going to take a red felt pen i'm going to outline where the bronze meets the seal and we'll see just how smooth it is so it comes up just a little bit there it's not bad and then this here it's a little hard to see where the bronze and the steel meet you have to look pretty carefully so it is it's fairly smooth you can see here how it comes out a little bit if it comes out that's a high spot if it goes in that's a low spot so this is not not too bad i've seen students frames where it's like a roller coaster it's like a look at like the alps or something so this is not bad and after i do use the use the belt sander it's going to smooth it out a little bit more in the comments there's been a lot of interest in in my belt center i made this years ago and it's getting a bit old so in an upcoming episode i'm going to make a new belt sander it's going to be the same style i might change the shape a little bit but you're going to see how this gets made and if you do the same thing i did you can save yourself hundreds of dollars because these are expensive so let's give this a go so i want you to watch how i'm easing in and easing off that's important [Applause] [Music] [Music] so that's one side down can you see now it's a little easy to see see how those two arcs are really even going around there that's basically what you want you want a nice smooth arc of the philip brays it looks good [Applause] see i had a couple little extra marks right there so what i did was to i just hung around that spot a little bit because i i i didn't want to go back and forth and and take more metal off here and here i just wanted to focus right there [Music] so what's left i've come this way and i've come that way and this is the hard part to get you see there it's right in the middle of the tube so i'm gonna show you a little trick that i learned over the years you see in behind the pulley right about there i call that a little sweet spot okay that's where i want to want to stand from i'm not standing back here most of the sanding i'm doing here happens here but now i'm going to go right in behind the belt in behind the wheel and also what i'm going to do is up to now i've been holding it up upright now i'm going to hold it at at about a 45 degree angle so i'm actually using just that that edge of the belt right there let's see what happens [Applause] it's done this is the last part so it's a three-part a three-part process off you do the braising brazing spiral roll uh belt sander and fine fingering i had a a student in frame building 101 his name was mario and he's the one that came up with the fine fingering name so it's stuck obviously so you just use a finger just go back and forth and it takes out all the marks of the belt sander it wasn't quite smooth there so a little extra for the point fingering okay that's what a a nice phillip braise looks like and the size of the fillet that's the size that i like some frame builders want a larger fillet some want a smaller one i think they're all about as strong that's just what i like so speaking of strength why don't we see how strong this is why don't we put it in the vice and i'll see if i can snap off this beautiful tangy tube okay years ago we used to have a race it was called the tesla metal it was the brody test of metal and mike true love he came up with that name and we're going to test this metal now we're going to see how strong the weld is where the two buckles if it buckles or breaks or splits we don't know what's gonna happen so it's a tangate tube eight five eight wall thickness as in in point eight point five point eight safety third wear my gloves i don't know what's going to happen oh okay okay so apparently the weld is fine and and and and that's where the butt ended so that's going to be the the end of the butt and so the butt starts here the butt ends there and that's where it broke at the end of the butt but the breeze is fine and that's what normally happens if it's tig welded or brazed it's usually not the world that breaks it's usually the tube that fails so that's kind of symmetrical thanks for watching our videos if you like what you see you can like you can subscribe there's links below there's a little arrow if you're on your phone show more on your computer we like coffee you can buy t-shirts mugs hoodies thanks for watching stay safe see you next week

Channel: paul brodie

Views: 127,874

Rating: 4.9337811 out of 5

Keywords: headtube, jig, fixture, alignment, frame building, framebuilding, steel, welding, lathe, metal work, metalwork, mill, filing, bicycle, custom, oxyacetylne, oxy-acetylene, brazing, rod, nickle silver, grit, sanding, sander, fillet, braze

Id: Y2CnJ9lmlQo

Length: 38min 44sec (2324 seconds)

Published: Sat Jan 30 2021