Need help with MIG welding car body panels

  1. JDMMX5

    JDMMX5 New Member

    Messages:
    7
    Location:
    Scotland
    Consistently blowing holes in sheet metal and would like some advice for how to avoid it
     
  2. Dcal

    Dcal Forum Supporter

    Messages:
    2,004
    Location:
    Antrim Northern Ireland
    Hi and welcome to the forum.

    Bit more info needed and pictures would help.
    What welder, wire, settings, gas or gas-less, if gas what type, how thick is the panel, what position - on the flat, vertical or upside down?
     
  3. rtcosic

    rtcosic Member

    At a guess I'd say NA MX-5 sills. Again.

    Welcome to the Forum.

    Search for MX 5 and you will find several threads on replacing sills.

    Read the MIG guides and practice the thin metal technique before tackling the car.

    Ensure you have cut away all the corroded metal. Welding to thinned panels is not really viable.
     
    stuvy likes this.
  4. JDMMX5

    JDMMX5 New Member

    Messages:
    7
    Location:
    Scotland
    Here is the patch panel I am currently trying to weld in, however it's blowing apart, welder is a Kramer 200 bi pulse MIG welder, gas is sureshield 5, 0.6mm copper coated wire. Did some practice pieces off to the side which worked fine however as soon as I go over to the real patch it just blows through
     
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  5. Morrisman

    Morrisman Forum Supporter

    Messages:
    2,071
    Location:
    Staffordshire, England
    Do a series of tacks, overlapping, hot on hot, one after another, rather than trying to do a bead.

    Make sure you have good ground clean bare metal before you start too.
     
    stuvy likes this.
  6. JDMMX5

    JDMMX5 New Member

    Messages:
    7
    Location:
    Scotland
    Is there a rough setting interns of current and voltage that I should be welding at?

    This is what I am currently welding at
     
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  7. mr haynes Member

    Messages:
    594
    Location:
    Scotland
    Voltage looks low, i'd expect to be around 16-17v
     
  8. JDMMX5

    JDMMX5 New Member

    Messages:
    7
    Location:
    Scotland
    Will try that out on another piece to test out
     
  9. Wozzaaah

    Wozzaaah The wizard of woz Staff Member

    Messages:
    14,843
    Wiltshire, UK
    60A!! No wonder you’re blowing holes.
    You need to be running at 30 or so, even lower if you can.
     
    Rusty, stuvy and rtcosic like this.
  10. mr haynes Member

    Messages:
    594
    Location:
    Scotland
    Looks like a multi inverter machine so the amps, i guess, should only relate to the other uses. Volts should be for mig.

    Going on assumption you are using 0.8/1mm steel to plate
     
  11. JDMMX5

    JDMMX5 New Member

    Messages:
    7
    Location:
    Scotland
    Yes the amps is the wire speed adjustment, and it's 0.8mm sheet yes
     
  12. Springerdinger

    Springerdinger memoirs of the mediocre diy mechanic

    Messages:
    430
    Location:
    UK nr Southam
    When I have thin metal I start off by have the welder set a little lower than the test piece setting. Then I do a series of 1 or two second tack welds spread along the join.
    Do a few spots like this and let it cool.
    Grind these small round welds flatter
    Then set the welder back to your preferred practice setting
    Starting at one of the tack welds to give you a good starting point do a one or two second weld. Then stop.
    Pick a different tack and do the same again. Let it cool
    You can then return to the first weld and so on.
    Say trigger on trigger off as you go.
    It's like doing lots tacks.
    You can grind it down as you go as well
     
  13. MyHouseIsOnFire Member

    Messages:
    97
    Location:
    Uk
    What is a good ball park setting of amp and wire speed for 1mm steel plate using 0.8mm flux wire?

    Thanks
     
  14. Lewis_RX8

    Lewis_RX8 Member

    Messages:
    375
    Location:
    Scotland


    Chrisfix went very in depth in this.

    If i remember from the video he showed the diagram for wire speed and volts to thickness. Just skip to the part where he sets the welder up.
     
    wacky7791 likes this.
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