Miller Electric

Welding Discussion Forums

Home » Resources » Communities » Welding Discussion Forums
 
Miller Welding Discussion Forums - Powered by vBulletin

Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: AC/DC welder

  1. #1
    Join Date
    Feb 2006
    Posts
    5

    Default AC/DC welder

    I have a question can someone tell me the advantages of a ac/dc over just an ac welder? Sorry if it is a dumb question. Curious
    Thanks
    Joe
    Tecumseh, MI

  2. #2
    Join Date
    Sep 2005
    Location
    Salem ,Ohio
    Posts
    3,861

    Cool

    Its easier to strike an arc, instead of peck peck peck with an ac you just light it up with dc. Plus some rods are dc only. 7018 ac rod is ok, but regular 7018 runs better on dc...Bob
    Bob Wright, Grandson of Tee Nee Boat Trailer Founder
    Metal Master Fab Salem, Oh 44460
    Birthplace of the Silver & Deming Drill
    1999 MM185 w/185 Spoolgun,1986 Thunderbolt AC/DC
    Spool Gun conversion. How To Do It. Below.
    http://www.millerwelds.com/resources...php?albumid=48

  3. #3
    Join Date
    Nov 2005
    Location
    michigan
    Posts
    47

    Default

    dc- deep penitration dc+ reverse less penitration for out of postion ( over head, vertical up, horizatol) ac least amout of penitration used for sheet metal
    miller 330 a/pb tig miller 175 mig
    student and hobbiest

  4. #4
    Join Date
    Sep 2002
    Location
    Clark County, NV
    Posts
    2,696

    Default

    Quote Originally Posted by link523
    dc- deep penitration dc+ reverse less penitration for out of postion ( over head, vertical up, horizatol) ac least amout of penitration used for sheet metal
    I think you got it backwards? For SMAW, DCEP (reverse polarity) gives greatest penetration. DCEN (straight polarity) gives the least. I almost never need it, even when out of position.

    AC will be in the middle for penetration, but you'll never use it unless you are trying to counter arc blow or something. The electrode selection for DC and its ease to use and less spatter will make DCEP just about all you ever want or need. DC is also much safer in damp conditions when it's easier to get shocked while welding or changing electrodes.

  5. #5
    Join Date
    Nov 2005
    Location
    michigan
    Posts
    47

    Default

    sorry your right i had it all wrong if you go to education at the top then welding libray then tech tips then arc welding there it is listed all currents an electrons you can use with each setting
    miller 330 a/pb tig miller 175 mig
    student and hobbiest

  6. #6
    Join Date
    Sep 2005
    Location
    S.W. Pennsylvania
    Posts
    2,249

    Default

    The only thing I can add here is to elaborate on what mac said about blowback. If youre metal is magnatized, this causes blowback and the AC helps combat that. An example of magnatized metal would be something that gets a lot of friction use like a hay elevator.
    Just thought I would add that untill last year all I had was an old Westinghouse 300 amp AC machine that has done a gaggle of welding. If you have an AC machine dont feel that you cant be productive, but if youre looking to buy a welder I would look for something that gives you the options of AC or DC.
    Last edited by burninbriar; 02-20-2006 at 02:57 PM.
    To all who contribute to this board.
    My sincere thanks , Pete.

    Pureox OA
    Westinghouse 300 amp AC stick
    Miller Syncrowave 250
    Hexacon 250 watt solder iron

  7. #7
    Join Date
    Feb 2006
    Location
    Beresford N.B., Canada
    Posts
    46

    Default

    Quote Originally Posted by aametalmaster
    Its easier to strike an arc, instead of peck peck peck with an ac you just light it up with dc. Plus some rods are dc only. 7018 ac rod is ok, but regular 7018 runs better on dc...Bob
    Not only works better, but also your work doesn't break!
    Save our species! Lower metal prices!

  8. #8
    Join Date
    Sep 2002
    Location
    Clark County, NV
    Posts
    2,696

    Default

    Quote Originally Posted by 2112
    Not only works better, but also your work doesn't break!
    No need to scare people looking to buy the hundreds of thousands of old used AC welders out there. Just as with DC welding, the skill is in the operator, not the machine. There are literally millions of structural welds out there made by AC buzzboxes that are perfectly fine and weren't all that much more difficult to perform.

  9. #9
    Join Date
    Feb 2006
    Location
    Beresford N.B., Canada
    Posts
    46

    Default

    Not trying to scare people. Just saying that some times, you get better results from a DC output. I've always been told that when using E7018 that you HAVE to use a DC output or else you don't get enough penetration.
    Save our species! Lower metal prices!

  10. #10
    Join Date
    Sep 2002
    Location
    Clark County, NV
    Posts
    2,696

    Default

    Quote Originally Posted by 2112
    Not trying to scare people. Just saying that some times, you get better results from a DC output. I've always been told that when using E7018 that you HAVE to use a DC output or else you don't get enough penetration.
    Agreed. DC is definitely smoother and easier and allows a greater selection of electrodes. Almost always worth the extra money when shopping for a machine.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Welding Projects

Special Offers: See the latest Miller deals and promotions.