mig and flux core tips and techniques, equipment, filler metal
hunter66
  • Posts:
  • Joined:
    Tue Aug 08, 2017 5:06 pm

Hi all I need some help to switch the polarity on my old mig welder, it is a sealy 200/1 mig and i want to convert it to gasless (flux wire) but there are no plus and minus points to swap around on this model so i need to retro fit some but dont know with wires to switch,i have some images but dont know how to post them on here so i can email them to you if that helps.

any help on this would be greatly appreciated
noddybrian
  • Posts:
  • Joined:
    Thu Jan 24, 2013 12:13 pm

Hi hunter66 - welcome to the forum.

A picture helps but it's pretty easy - follow the earth ( -ve ) lead inside the machine - remove & connect to wire drive - remove original positive wire from wire drive & connect to earth lead - hopefully there is enough slack to use original ends & they have bolt on rings.
If you intend to swap on a regular basis then maybe order small dinse connectors from Ebay & put both output leads from the machine on chassis sockets & a short fly lead from the wire drive so you can plug in either way round.
hunter66
  • Posts:
  • Joined:
    Tue Aug 08, 2017 5:06 pm

]Hi Noddybrian

Thanks for the quick reply, I have pictures but don't know if you can upload to this forum I could mail direct to you if that helps?

when i look in the machine you can follow the earth clamp easily as it is thick, but the cable to the gun is difficult as all i can see is two thin wires that go to the spool red and black. and then they look to go to the switch on the front of the machine.

Don't really want to be cutting wires if they are the wrong ones :(

ps added a link to a picture as i was writing don't know if it will work you can always copy and past in to google

https://i.imgur.com/wuDgPpP.jpg]
Artie F. Emm
  • Posts:
  • Joined:
    Thu Jul 24, 2014 7:53 am

Is your machine similar enough to this one that this video could provide info?

https://www.google.com/url?sa=t&source= ... DbdRXeQohw

Welcome to the forum, btw!
Dave
aka "RTFM"
Artie F. Emm
  • Posts:
  • Joined:
    Thu Jul 24, 2014 7:53 am

This links to a Sealey conversion, although it is not the 200/1 model.

http://www.mig-welding.co.uk/forum/thre ... -go.45443/
Dave
aka "RTFM"
hunter66
  • Posts:
  • Joined:
    Tue Aug 08, 2017 5:06 pm

thanks Dave
aka "RTFM"

Ive seen this video before, on mine it is easy to locate the earth (clamp cable) and follow it , but the positive lead from the gun is not so easy, there are two small wires red and black which come from the gun to the spool tensioner which feeds the wire other than that i cant see anymore. nothing as thick as the earth cable.
noddybrian
  • Posts:
  • Joined:
    Thu Jan 24, 2013 12:13 pm

I can't really see the earth or live in the picture - but you can clearly see the rectifier - 2wires come from the main transformer (ac ) the other 2 coming away from the rectifier are dc welding power - one earth the other is live going to the torch - I rather think the aluminum flat bar with a slow bent heading forwards over the transformer is the live - it will bolt onto the wire drive assembly & all the drive will be live - the 2small wires are go to the torch switch - the power travels up the torch hose in concentric arrangement much like coaxial cable - inner part is liner for wire feed then rubber then power braiding then insulation then switch wire then outer sheath - just find a thick cable or buzz bar heading from the wire drive to the rectifier & that will be the positive - you should be able to swap hopefully with what is there - if not consider making add on short leads with dinze connectors on to allow easy swapping.
hunter66
  • Posts:
  • Joined:
    Tue Aug 08, 2017 5:06 pm

Hi still need a little help on this

so in the picture i have added letters
A is fron the earth clamp
B is where iasume the earth clamp comes out
Cis where the earth ends up
D is the live from the torch ( i hope)
E is where the live go to

Hope i am correct so far

F is a second live ( i presume because this machine has a spot welding function)
G is where it ends up ( but you cant see this on the picture)

So I switched E and C and removed G but there was no ark
then I switch the E and G cable still no ark
then i reconnected the G cable (still no ark but it did trip my fuse box)

any help on this confusion there is a link below for the image

https://ibb.co/hFFwev
noddybrian
  • Posts:
  • Joined:
    Thu Jan 24, 2013 12:13 pm

OK - I hope not to hurt your feelings / pride or offend - BUT from your questions & what you have been trying I think you are likely going to hurt yourself or the welder & should seek someone with a small amount of electrical knowledge.

If you really want to continue I'm having trouble on the little screen I'm looking at the picture on being certain what goes where as the only things you need to see are the earth lead connection & wire drive - I can not see either clearly or directly in your picture - also hard to see what the letters mean as they are not too big & not directly on a connection - but here is my opinion

E & F are mains wires to the thermal trip & should never be messed with or connected to the DC welding side
B & C should remain connected always - this is the negative welding power from the rectifier to the inductance
G - if this is the flat aluminum bar with a slow bend heading forwards this is the live DC welding power
A must therefore be the earth lead though it's not visible
So as already mentioned all you swap is the +ve & -ve welding power so it's A & G that swap - I think you will end up needing some flexible cable in place of the bar to achieve this hence the suggestion to put a fly lead out front with a dinze connector if you plan to swap around much.

Pretty much any one with welding experience can do this for you or show you how it's done - it maybe worth sharing your location & seeing if there are any members close enough to help out - if so many will do it for free or at worst bring beer / doughnuts ! Hope you have some success & not smoke !
hunter66
  • Posts:
  • Joined:
    Tue Aug 08, 2017 5:06 pm

tough skin you wont hurt my feelings ;)

the clamp goes to A and then it looks like it comes out where B is and finishes at C
THe curved metal bar at the far back right in the picture has no wire to it and the closest wire is -G which comes from F the box at the bottom

I live in Sweden so don't think there will be anyone close :)
noddybrian
  • Posts:
  • Joined:
    Thu Jan 24, 2013 12:13 pm

There are a few of your countrymen here even if they don't post regularly but how close is anyone's guess.

From what I can see - at the bottom is the main transformer this has 2 thick output leads carrying welding power still AC at this time to the rectifier - usually there will be only 4 thick connections to this - the other 2 are therefore the DC welding power - the earth goes via the inductance coil to the earth clamp - the other which I think is the curved flat bar is the live going to the wire drive - maybe you can confirm there are only 4 connections on the rectifier & no others out of easy view in the picture - the AC from the transformer to the rectifier are never moved & the inductance always remains connected so unless you can provide any other pictures showing more or information to the contrary it's worth swapping the earth to G & the wire drive to A - I think you will find that the flat bar if you follow it is bolted to the wire drive somewhere which is insulated from the surrounding metalwork - let us know how you get on if you try it - hope it works out for you.
Post Reply