Sorry - Need help with 90A HF mod toroid

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Brand new to the site so please be gentle.

I am doing the mod to your basic HF 90A AC welder to DC.  Got 200A rectifier, and a 100,000uf cap, connectors and 8AWG flex wire and also a transformer to run the wire feed motor through the trigger relay.  The question I can't seem to get an answer to is about the induction coil or choke.  I started asking this on an EE forum site here.Naturally the EE folks got very VERY technical and wanted me to calculate the inductance of the coil etc.  All I want to know is if I wrap a stripped down toroid core from a power amp with as many wraps of 8AWG wire as I can will that be a worthwhile improvement and is there any reason I should not?  I was about to just not do that part of the mod then I somehow happened onto this site which seems a little more user friendly (not that they weren't friendly) for a woodworker like me.Yes, I could just buy another welder but where's the fun in that?Any help would be much appreciated.Last edited by Andybb; 02-01-2019 at 09:35 PM.
Reply:Wire welders are meant to be a constant voltage output. Capacitors work on voltage, inductors work on current. So in MIG welders you see large banks of capacitors and in constant current machines like stick welders you see large inductors as filters. For what you are doing, I would put a small inductors or none at all. I definitely would not put a big honking inductor/choke in there.Miller Multimatic 255
Reply:Back when I had the HF 90A welder I was considering the same mod as you.  There are several threads on doing the mod in the HF forum and I remember reading lots of discussion on the if/how to use a choke.  Have you done a forum search?  I attached a link to one of the discussions below.https://weldingweb.com/vbb/showthread.ph...-to-DCEN-ReduxLast edited by jrporter; 02-01-2019 at 10:32 PM.Tweco Fabricator 211iSieg X2 AMT radial arm drill pressAMT belt/disk sanderHF 4X6 bandsaw
Reply:

Originally Posted by jrporter

Back when I had the HF 90A welder I was considering the same mod as you.  There are several threads on doing the mod in the HF forum and I remember reading lots of discussion on the if/how to use a choke.  Have you done a forum search?  I attached a link to one of the discussions below.https://weldingweb.com/vbb/showthread.ph...-to-DCEN-Redux
Reply:Are you doing this because you like to tinker, or are you doing this to save money? If the latter, what is your time worth? I really do think you would be better served by one of these.  https://www.harborfreight.com/weldin...put-64804.htmlMiller Multimatic 255
Reply:The inductor is needed on the output, if you don't have one, it is like welding with car batteries.I can measure the one on a small Hobart welder, but how you would measure and translate it to what you have ?You   might look for inductors added to batteries for some ideas.
Reply:

Originally Posted by Louie1961

Are you doing this because you like to tinker, or are you doing this to save money? If the latter, what is your time worth? I really do think you would be better served by one of these.  https://www.harborfreight.com/weldin...put-64804.html
Reply:Just like to tinker
Reply:The old early model Harbor Freight Migs came with a good sized inducter in the torch circuit,  at least mine did,     what it was missing was a capacitor(s)1962 Idealarc Tig  300 300 1974 Idealarc Tig  300 300  ( till owner needs it back) 1988 Power Mig 150 (.112 f cap mod) 2015  Lotos Ltpdc2000d plasma/arc/tig    Victor 100 torch, 200- 210 Oxy/Acet gauges
Reply:I don't have that machine but what 455dan said. Get the caps and bridge rectumfrier. Your reactor (coil) was designed for that size of machine, don't mess with it. Design of inductors depends on wire size ( gauge), number of turns, diameter of coil and a formula. I may have left something out but that's the basic. Mig is a constant voltage process and needs the caps to keep the voltage stable/constant. I can't understand why they even make a mig machine with ac only.
Reply:As near as I remember, the AC wire feeds don't have a choke or reactor coil.