Making a Rotary Ground Clamp for Welding Shop Made Tools

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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

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