Making a Rotary Ground Clamp for Welding | Shop Made Tools
how you going guys Kurtis from cutting edge engineering for today's video we're going to be making one of our shop made rotary earth clamps you might have seen me using the rotary earth clamp on our welding rotator for doing cylinder rods and barrels there's been a lot of people comment on where we got it from well we didn't get it from anywhere we actually made it it is simply a rotating device that allows current to pass through it so it can rotate freely while you are welding something that is rotating on say a positioner or on a set of rollers without a rotating earth clamp it can be quite difficult to weld parts that you are rotating and the reason for that is every couple of rotations you would have to stop the welding process take your earth clamp off straighten it out get all the coils out of it put it back on and then you would continue to do that until you had completed the job one of the other issues is you forget to take the earth clamp up off and straighten it out you can actually pull the job off the rollers or flip the welder over because all of a sudden the welder is being pulled into the job while it's rotating there are other methods where you can strip a piece of welding cable and wrap it around the job that wasn't a solution for me i do have the ability to make stuff like this so i decided to just make one so these are a very basic concepts they're very easy to make if you have access to a lathe and a drill or even a milling machine you could definitely make one of these without too much trouble basically what a rotary earth clamp is it is two pieces of brass that are held together with a bolt and a spring and the rotary earth clamp we make today we will be giving it away to one of our subscribers so keep watching to find out how you can win it today is actually a saturday so there's not many places open today in order to go and get stuff so everything that i will be using to make our new rotary earth clamp is already here at the workshop i've gone through and found everything i'm going to need except the most important part which was the main body of the earth clamp i did have a piece of brass to start this job and i found out it wasn't solid bar it was hollow bar so unfortunately i don't have the main piece but that's fine i do have a solution for that so what i've got is i have a lot of off cuts of hex brass that are leftovers from a job we do quite often here in the workshop it is the wrong shape but i am going to melt it down and turn it into the two blanks that i need and to melt it down i'm going to be using my baby devil forge so the devil forge was a bit of an impulse buy i was watching big stacked a fair few years ago and watching him melt down materials and making coins and stuff like that and i thought that'd be a great way for me to make copper hammerheads for the machining side of the workshop when you use a copper face hammer to hammer something that is very very hard it generally mushrooms the end of the hammer face over and it then starts to break apart these are really really good because you can actually replace the faces of the copper hammer very easily they are very expensive to replace because they are a certain size for these hammers so i decided i was going to give it a go myself and i'm the first to admit i am not good at it first time i used this i actually destroyed a fair few muffin trays and cake tin stuff like that because i saw other people doing it on youtube and thought i can do that i don't really know what i'm doing i've watched enough bigstackD to sort of fluff my way through it but if you want to see someone use it correctly go watch his channel he's very good at what he does this is one of these smaller devil forges i'm not sure how many sizes there are crucibles i bought are far too large for this devil forge but we're going to try and make it work anyway for the moulds i'll be pouring the brass into they are two old bushes that a customer had left here they weren't a very good quality so we ended up changing them out to some genuine parts he didn't want these ones back and i decided they would be a great fit for the size of the molds to cast the material into so it's just two bushes sitting on two bits of 10mm plate because karen won't let me use any more muffin trays i am fully aware there are a lot of things wrong with this setup but we're just going to run with it and see how it goes overload oh oh dear right so that went really really well i'm absolutely amazed that worked so very happy with that that'll be perfect for our rotary earth clamp now we're going to take them over the lathe and start machining drop it stay stay get it right oh so what we're going to do now is we're going to machine these blanks down just to clean them up there is no set size you would need to make these in order to make a rotary earth clamp but you do need to keep in mind that you have you're going to have a lot of heat being generated in this area just because it is rotating and there is power passing through it small is not good you do need to have a bit of body there in order for them to be able to handle the heat and handle the current but you don't want it to be too big because too big means it's going to be really heavy and they do have a habit of breaking the tacks and falling on the ground if you want to put a decent stitch on there so it doesn't fall off that's fine but i don't see any need for them to be overly big so we're starting with a blank that is 78 mil in diameter and it's about 32 mil thick so i'm just going to machine these down so they clean up right so i've cleaned up the faces of the first blank it did clean up to about 21 and a half mil what i'm going to do now i'm going to punch a 20 mil hole through it and that hole will serve as the way i hold it in order to clean up the outside of the blank and it'll also be a good start for the bolt and the thread that i need to put in each blank might get it righto so the lathe work is now complete for our two blanks the reason i bored them and gave them a very light facing cut is those two surfaces have to meet each other perfectly and they have to be concentric and true because if the two areas don't meet perfectly they tend to walk around a bit and they create an arc on the inside it would not work correctly when you are making rotary earth clamps and anything like that there are other materials you can substitute other than brass so you could use aluminium you could use copper a combination of brass and steel or aluminium and steel and one of the materials you want to avoid is steel on steel the reason for that is if they do separate slightly they create an arc between them and sooner or later they pretty much weld themselves together so now we've got the two blanks done we're going to get on to machining the bolt that holds those two parts together and what we're going to be using for that is a piece of 30 mil hex brass which is also an off cut from a previous job i can't do it i've got to do it properly right so that's all the lathe work done what we need to do now we need to go over to the milling machine we have one hole to drill and tap and then we can start to assemble the rotary earth clamp get it that's cute [squeaks] [giggle] they're all edge finders oh my god [giggle] all different types i don't break them that often but thank you very much for the new edge finders what we're going to do now we're going to drill and tap one hole in one of the blanks and that is so you can then attach the earth clamp onto the welder righto guys so all the machining is now complete we are now ready to assemble this but as i said in the start of the video this is going to be a giveaway and all you need to do to enter is guess the exact weight or to the closest gram of the brass components that is in the earth clamp leave a comment what you think its weight is the first person to guess the exact weight to the gram will win it but if no one guesses the exact weight it'll go to the person that has the closest guess so check out the description for the full terms and conditions on the giveaway we've got all the parts laid out here we have the main bolt made from brass that we machined the two blanks that we've actually turned into the two conducting faces we then have a spring a bolt and two nuts so we're going to put that together and just show you how it all works so that is the earth clamp put together the black bolt is the sacrificial piece of material that you can then tack onto a job and then when you do finally wear it out or you've ground it off too much you simply take the bolt out and put a new one in its place we also have the main body of the earth clamp which are your two conducting plates one of them is locked to the thread using a jam nut the top plate of the earth clamp it stays stationary while the rest of the clamp turns with the job and it is spring-loaded to hold weight against it so while it's rotating it is creating a good contact area for the current to pass through it there are two ways you could attach an earth lead to the rotating earth clamp the way i do it is i have a single bolt that i screw into the body of the earth clamp and then i attach my earth clamp from my welder straight onto that the other way you could do it is you could use a crimp on end which you can fit to your welding leads and bolt it straight down on top of that flat area there and it can then stay on that earth clamp all the time i prefer the bolt method because the welders are used everywhere in the workshop rather than having two different leads i have the one lead and it's very quick and easy just to attach or detach my earth clamp so if you were to go and buy a rotary earth clamp from a supplier of some nature you would expect to pay between 60 to 600 dollars depending on what you want quality wise will depend on how much you spend so if you were going to go and make one of these it would cost you about a hundred dollars in material and one to two hours of your time depending on your capabilities and what sort of access you have to machinery this is one style and one of the many ways you could make a rotary earth clamp there are a lot out there on the market it just sort of comes down to what suits you so that's how we made our rotary earth clamp thanks for watching how you going guys Kurtis from cutting edge engineering so for today's job we're going to be wait how you going guys Kurtis uh [ __ ] we're going to make a new rotary earth clamp [ __ ] so keep [ __ ] so keep watching [ __ ] what did you say oh my god i'm having a moment you are so they're very easy to make yeah that's about it [giggle] so what i've got is a lot of off cuts of hex brass that i do from oh [ __ ] that i have right they don't need oh where am i going with that i don't know was that all you wanted there [sigh] and it then becomes notchy notchy is that a word i don't know what you mean by that right we're gonna get onto and one of the materials you want to avoid for using oh for mani uh and you want to avoid steel on steel when you're make uh [ __ ] don't you smile stop just do it right one take wonder Kurtis right righto guys so all the machining of the oh [ __ ] me will go to the person it will go to the [ __ ] it'll go to the person that has the closest guess to its weight to the gram so check out the full ugh check out the description in the video on the video in the video so the way you enter this all you need to do is cop [ __ ] off train i was going good no you weren't yeah i [ __ ] was let's keep going to get the right take oh god yeah save me jesus he can't save you [giggle] hang on let me start that again [ __ ] [ __ ] [ __ ] i've lost it i'm over it so yeah i'm as shocked as you are that worked shit's gonna go everywhere [ __ ] brass goes [ __ ] everywhere very good go away train that's neat all different types double ended wait [Laughter] it has two ends that you can use for center finding or edge finding oh what's wrong where's your banana go get it you got it hey yeah yeah you got it and it still squeaks
2022-06-27 21:57
