Hello Tommy, finally got a chance to read your post a bit more carefully. Nylon can have some electrically conductive properties, I believe UHMW will not, as it is different from nylon. Having said all of that, there are a number of different types of UHMW and other "plastics", all of them have distinct properties that make them suitable for different types of applications. Many are very resistant to heat, others to impact, still others to friction and wear. In my geographical area many of the mills use a blue colored UHMW to make pins for impact/wear applications, I believe this particular type might serve your purpose well, unfortunately I don't have a specific manufacturer/grade/identification number that I could give to you.
Some time ago I built a powered rotator for chucking up large parts to be welded on while being rotated. Fitted the rotator shaft with a brass race and then set-up some brush holders to hold brushes(out of a large engine drive machine such as a: SA-200, SA-250, SA-300, I believe you get the idea), as the shaft rotated the ground was attached to an insulated terminal that was attached to these brushes. They were large enough and had large enough pigtails on them to handle 4 to 600 amps pretty well. You may find a configuration based on something like this will work well for your application. Be sure to keep us all posted and if at all possible post up pictures. Best of luck and regards, Allan
THX for the replies The drive I am going to use is a 120v variable speed (50-400) geared conveyor drive motor, has the rheostat and everything already on it. I am going to gear that down a bit with sheaves and a belt. I got some spare spider gears? out of a chevy rear end I am going to use for a secondary drive to operate the wrap guides via old locomotive style bell crank. Hand wrapping 300-400 feet of lead is a chore and I feel too dang old for that at the end of the day!
Allan thx for the tip, something in my brain was telling me easy to get nylon was not going to work. I do not know what UHMW is but I will look it up and see how hard it is to get ($). Is that the same thing as the grey plastic electrical conduit? I will definitely post up picks when I get it built, might be a while as it is a side project mainly for the fun of it. The brushes sound like a good idea, all I need is about a 450 amp DC capacity.
MY SECOND question is this..... How many feet of lead can you have coiled up on a reel before magnetism interferes with your welding quality, starts damaging your leads from heat or for that matter your machine? I realize that in A/C welding you will have an issue with hysterises that can cause heat buildup in your coiled lead and also reduce your overall current directly dependent on how much lead/how many wraps you have. In DC welding this should not be an issue, except for natural current heat buildup right? What I am using is 2/0 carol and hardly ever will break 200 amps. At least right now anyway. Lead is just too expensive for me to be burning it up.
Hello again Tommy, might make more sense from that perspective to not use the reels to roll-out and use with current flowing through them. Instead, load reels up with 50', 75', or 100' lengths of of lead connected end for end and then connect them to your machine, as needed, to make your particular length of run. In that manner you would be less likely to have issues of heat, arc blow or other problems from leaving leads coiled while using them. Just a thought. Best regards, Allan
You should be able to purchase UHMW through Mcmaster-Carr or possibly Grainger. Micarta would also be another great insulating option for you. If not familiar with Micarta, it is the same material used in flange insulator kits (the bolt washers) as well as my Wendys pancake.
As long as You don't use a "filled" nylon You wil be Ok. Nylon 6 or 66 come to mind. UHMWPE or HDPE should be OK too.
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