TFS: Custom 4 Links Part 1

so I'm over at my buddy's house the other day and he's building up his 61 caddy it's all bagged out thing weighs as much as a house and the previous builder on it didn't do the most satisfactory job I mean this arms looking a little dated and not to mention we have some geometry that we have to correct on it so since the original design used shims that are a little bit dated you know we got a we got to fix this so that presents the perfect opportunity for me to get in here start up a video and say here's how to build some extra big-ass four links now equipped with more molecules you [Music] now I'm definitely not going to call this a hack job or anything like that I mean we all start somewhere right so we need to correct some of this stuff I don't really care for this bag mount the way it's sitting on there you can tell the arm is pretty twisted up or this lower link a little messed up but yeah well uh we gonna fix this it's just it's just not enough so some things you need to pay attention to when it gets dropped off it may have two different size bolts like this one one side is a 9/16 while the other side is a 5/8 now I don't know if that was from the factory or not but that's what came off the car and that means that's what the chassis has in it those are the size holes so these poly bushings they're obviously you know we're not going to keep these they're just there whatever so we need to make a jig in order to make a jig we're just gonna take a couple of bolts the correct size bolts one of them of 5/8 the other one a 9/16 and I'm gonna remove the zinc coating or grind it off of just two sides it doesn't need to be you know super heavy-duty or anything like that it's just just enough to basically hold the place and that's all a jig does once I have the zinc removed we're gonna face it off in the in the lathe now not a necessary step if you don't have a lathe or you can't do this don't worry about it all this is doing for me is basically giving me a nice flat and even surface in which to mount or weld all of this on the on the jig now a lot of people overcomplicate jigs I don't really know why but just think very simple all it is is a placeholder nothing more that's why we only need just a couple of spots to weld on these bolts alright nothing fancy at all so I'm gonna tack it on there one tack on each side and that's just enough to hold it in place and you know kind of help minimize distortion while it holds the place of where the new pieces and parts need to be when I make this now we can't weld it fully otherwise we're gonna melt away on the most poly bushings there and that's just you know it's kind of cheesy so remove it after tacking and fully weld each side this is more than enough to hold it in place now this jig is nothing more than some like believe 1 by 2 rectangle tubing with 1/8 inch wall that's more than sufficient just as long as it holds everything in place so as soon as we have all the bolts welded let's move on so I'm gonna start with the ends now the ends are going to be basically standardized now before we had two different size bushings and two different size bolts that went in there and that's kind of a pain in the butt if you have a need to replace anything so if we standardize them and make them out of the same size bushing and same size housing for that bushing the only thing that changes is the size of the pin in the center of it that holds the bolt so we're gonna start with some 2-inch o d d om tubing with a quarter inch wall this is some big heavy-duty stuff now as most do M has it there is a mil scale that's on the outside of it which means that has to be removed the fastest and smoothest way I found to remove it is to check it up into the lathe spin it with some Emery cloth and then polish it up with a piece of scotch brite or a surface prep pad now this is gonna get it perfectly ready to weld nice and clean everything that I want now we need some solid clean metal on here to get some solid clean welds out of it so this is a step you definitely don't want to skip over now if you don't have a lay there any way to spin it around you can definitely use some basically some surface prep pads on grinding wheels or anything of the similar the like you know you can do it all by hand the lathe just makes it go a little bit quicker now these are my poly bushings right here I'm gonna go ahead and take a measurement of these can then like I said they're gonna be standardized so for pieces to build two links one on each side two and a half inches is the measurement and the bandsaw is what's gonna get it cut to length now if I wanted to be all fancy I could spin this out in the lathe but realistically speaking the bandsaw will do the job just fine just slice all these out for pieces and then we can move on to what's next since polyurethane is our bushing material we know that earlier since we try to tack it up with you know in the jig there it started smoking one of them out and we don't want to melt it so we definitely can't use polyurethane bushings in the actual bushing ends while we're welding it otherwise they're just gonna melt so there are companies that make and sell bushing dummies basically a solid aluminum bushings that will hold the place of the the ends or the four link ends or the bushing ends or the housings while you weld it all right now I'm not going to buy those since I have a lathe and it gives me an opportunity to show you guys you know how it's done so I'm going to start with some two inch solid bar stock now this is all just nothing more than just some aluminum right nothing fancy I'm gonna chuck it up into the lathe I'm gonna face it off first way I have a nice clean surface to work on pop a hole right in the middle of it this will be the size of our bolt then I'm gonna go ahead and start cutting it down now when I cut it down to a size all I'm doing is just cutting out a shoulder and making sure that the top end of the bushing now that stop where the shoulder is or the top that's gonna sit around the outside of the tubing that has to be basically standard and I'm gonna cut that to length in a quarter inch actually just a little bit more so that way when I take it out of there and we you know after it's already cut I'm gonna flip it around and I'm gonna face off the front of it and make sure it comes down to exactly a quarter inch tall that means that we won't have any kind of miss crepin C or misalignment with our bushings now if you don't have these there are alternative solutions those solutions might be using solid bar stock for the ID of the tubing that you're using on the bushing ends you know you can use that you can use a stack of washers welded together or something or basically anything that holds that place will do the trick now I know I just kind of flew right through that machining but you know it's it's it's really simple it's just to show you guys kind of how it works or how they're made or how you could do it to so with all of that done we can slide the dummy bushings into the housings get him all fitted up to the jig and we can start measuring for our four link adjustability is definitely one of those things that I want to incorporate into this because the original system on the Cadillac itself use these really funny looking for bolt shims which I don't even know if you can get those anymore but who cares we can we can completely eliminate them and basically standardize everything like we are with everything else so this gigantic inch in 1/8 pin is what we're gonna use for adjustment now you have to measure out your usable threads on this and in this case when I measure them out it comes out to about an inch or so of usable threads so I want to make sure that the jam nut is basically up against the the housing there that bushing there I want it to be at exactly one inch so that way we have the same amount of inward and outward movement and it still maintains some strength at the standard number or at the basically at the point where it is at factory length so now there's a lot of math that goes into deciding how thick or how big your links need to be and I'm not gonna get too far into that you kind of have to know how much you know ultimate strength they have tensile strength yield string all the rest of that combined with the ratios of how your setup is and all the rest that's a totally different topic but I'm using quarter inch wall square tubing because it's more than strong enough and of course is giant pain and everything else like that this bushing goes into it so with a quarter inch wall bushing we need a lot of area to weld so that bushing is not going to slip right in the end of the tube it's actually going to protrude a little bit so I'm gonna stick it out about a half of an inch now I'm gonna measure from the inside of the bushing housing to that mark that I just threw down on the actual pin bushing now this is gonna give me a general ballpark reference of what I need to cut my store tubing to now my tubing of choice two by two square tubing with a quarter inch wall this is some heavy-duty stuff usually what they make trailer receiver hitches and stuff like that out of this is uh this will definitely do the job and of course I backed it up with the math to calculate all that now just slicing it down in the bandsaw and then we have to notch out one side now since our bushing housings are round and our four-leg material is square that means we need to cut a round a notch into the square side it's really not rocket science a hole saw will do the job just like it well with many other notching methods or different shapes and such now this I'm just gonna chuck it up into the mill that way I get it all nice and squared and set up exactly where I need to my cut can be measured and placed right down the middle exactly where I want it to be it's very very simple now there's a bunch of different methods you can use here you can actually put a little center hole into it and use a hand drill to you know chop its way down through there you can grab a hold of a tubing not sure one of my favorites is the rogue fabrication versa not sure that thing is really awesome it'll little BA it'll not shot some square tube as well but really nothing all that fancy now just remember that virtually every single hole saw has its limitations and that limitation on this one is less than two inches so I obviously have to you know take this back out of there and remove that other piece so I can finish off the notch all from one side otherwise I'd have to flip it over and try to line it up again not gonna happen but pretty simple we just get it all notched out and then I'm gonna chase it out with the grinder now being that this is a quarter of an inch thick we're gonna pretty much be struggling if we try to nail it all in one single pass I mean we're talking we'd have to have a ton of amperage and we'd have to fly right through it and you know there's there's a possibility that it might not come out just right instead I want to increase the surface area of the weld that means that I'm gonna knock a big old fat gnarly bevel into this and we're gonna run multipass welds on it the first weld is gonna go right down into the root give us our good solid fusion which I can run nice and slow with and the second will be the cap to fill it all in and also with this bevel on here we're actually increasing the surface area so the amount that I'm cutting out about 1/8 inch there's an eighth inch land on it or an eighth of an inch or about half of the tubing that is not ground away the other is ground about 45 degrees or so back this effectively increases our surface area giving the weld more to bite onto now forget about measuring this you know to length trying to figure out what how long the four-link bar needs to be there's a cool little trick earlier we marked out the amount of protrusion that we want for the actual bushing for the where the pin bushing goes into we marked out the amount of protrusion that we want out of it so place that over the top while everything is in the jig and translate that line right down on to the actual tubing itself that line will be the correct length that you need to chop this down to in order to make all of it fit it'll work the exact same way every single time because you're using a jig now just like before we're gonna clean this up and with a grinder I'm gonna face it off with a grinder so that way it's nice clean bright metal everything is nice and prepped and I'm also gonna add a bevel to it the same bevel is gonna go on to it about an eighth of an inch land roughly 45 degrees beveled back and I'm gonna clean up everything around and all the edges now even though we're not welding like the actual sides of the tube itself we're welding the end of it I'm still gonna clean it up just in case something changes or you know plans change whatever I want nice clean bright metal so now it's time for everybody's favorite part including mine and that is the welding so I'm gonna get this fixed to the jig now notice I have some spacers at the bottom that keep it in place aligned right down the center where it needs to be that's extremely important because you don't want this thing to be all crooked or anything like that I mean take a couple extra steps measure it out make sure it's dead center now as far as tacking this together or welding it in the jig we want to have at least three tacks holding it together usually I say tacking quadrants which is for tacks spaced evenly apart but since I can't access the bottom of the jig three tacks will do three tacks will keep it nice and solid now all of my route passes with as much as I can you are going to be while it's in the jig and of course this area where we have the bung that goes into the square side unfortunately the manufacturer whoever made this thing didn't make it big enough to go into there so we're gonna have to deal with those holes a little bit later and it's not like they're difficult to do I just wish they'd you know wouldn't have cut those corners so short I should have just made one instead of not one but whatever anyway back to the welding here all route passes once again or at least as much as I can cover is going to be done in the jig currently the welder is set up to I believe a hundred and sixty-five maybe 170 amps I honestly can't remember where I had it out it was a little on the higher side my welder filler rod is er 70s - - and I'm using oh four five that's I think like 1.1 millimeter or so it's very small stuff now you would think that you gotta you know throw in a ton here in order to get this in there but it's actually the opposite I want to add more filler wire to my weld pool to establish the bead and I want the control over it so we have to do that with smaller filler wire not necessarily larger so we can always add more from a smaller filler rod but we can't always add less from a larger one so oh four five filler wire and we're just really pushing it in there making sure it all wets in and blends and bleeds to both the sides of the land and of course on to the actual bushing housing itself making sure it stays nice and tight and I mean super tight I am full throttle the entire way through so with all the roots done or at least as many as I can do while it's in the jig i'ma let it cool down for a few minutes and then I can pull it out of the jig and then finish off the route passes on the on the you know three spots where I couldn't get them before so that's at this end with the bushing housing and then I'm also going to do the pin one more time and I don't believe I showed it on this one but I also did that other section where the the bung goes in now speaking of that bung this is that big pesky gap we get a deal with now I use the same amount of amperage again except this time I've increased my filler rod diameter to two point four millimeter or 332nd now this I'm just gonna run just a little bead over the bottom of it and then force-feed some filler wire up to bleed it up into the top or blend up into the top now I only got that one arc shot out of it unfortunately I was a little too uncomfortable and this is a you know critical weld but if you watch my hand I weave it to get it to fill and blend in now we're gonna have to rely a lot more on the cap to maintain most of that structure I mean there's a lot of good amount in the the actual route but the cap is gonna really dial that one and or polish it off now speaking of caps I'm gonna leave now at least on this bushing in here on the bushing housing I'm gonna weave on the flat sections of it but on the radius section there's not enough room or any need to weave it instead I just up to my filler rod diameter to 1/16 and filled it just very heavy I did not do anything with the amperage I'm still about 160 570 amps full throttle but I did allow the piece to cool about 20 minutes before I went into doing the caps on it now this weave it's just back and forth to push and blend it and make sure that we have enough weld or enough filler basically to bridge that gap make it nice flat and even I could have run two or three passes on this or whatever you know I mean what would he do but we've just decide from you know being you know having the strength and everything else like that it's just I just kind of want it to look pretty you know if you had a chance to show it off for those who are actually looking and once again going around the radius just you know nice big old fat stacks making sure it blends and bleeds and wets in into both the face of the tube and the this section of the radius now finally is the pin now this you know that o45 wire is very tight and I trust that it was just fine but again we need big fat heavy amperage on here and we're gonna throw down a big old giant of big old giant bead it's on this one it's kind of hard to tell where it wets in or anything like that but as long as it extends past and it covers every section the way it's supposed to we're good the more solid that's really all I need but one thing I'm going to point out extremely important here I did not start or terminate any of those cap beads where the original root bead started or terminated we did not do any of that we made sure that we actually welded over those and all of my start and stop areas on the the cap pass we're done while they were the one that we were in between all the start stops on the root so very important that you do that now once we have both of them completely welded weak set it up right next to the original one you can see what a massive difference this makes now I do have to build some bag brackets and I'll put those on at a later date when I can actually measure them out on the chassis but this it's pretty stout now here's the fun part I still got to build this upper now this is uh this is going to be interesting because it's not really like I can take a bunch of off-the-shelf parts and make it all happen and yeah we still have some that corrective geometry we got to work with so that's going to come up on a future episode and it also involves somebody else helping me out on the machining end of things so we'll have more updates as they come but that is gonna wrap it up for this episode I want to thank you guys for watching as always make sure you subscribe and you ring that bell now if you have any questions or comments go ahead and drop them down in the comments box below if you need to get in touch list you can always hit us up on the fabrication series.com website Instagram at doc fabricator where facebook.com/ slash the fabricator series I'll see you guys on the next episode I like money

Channel: The Fabrication Series

Views: 1,051,790

Rating: 4.8926978 out of 5

Keywords: Multi pass welds, custom 4 links, 4 link fabrication, 4 links, build a 4 link, bagged caddy, make 4 links, fabricate 4 links, trailing arm fab, lower control arm fab, Season 4, The Fabricator, #GetStrong

Id: aIGTNU6hG2Q

Length: 17min 15sec (1035 seconds)

Published: Fri Feb 08 2019