Material building up on plasma torch

Discussion in 'CNC Cutting' started by Rod Back, Apr 18, 2017.

  1. Rod Back

    Rod Back Member

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    I have the 4800 table with the flexcut 80. When making long, straight cuts, molten metal forms on the torch head and eventually causes it to either move off its path or crash into the plate. What is causing the molten metal to form and how do I correct it?
     
  2. LECS-Chad

    LECS-Chad Guest

    What are your settings? Cut height/amperage and what thickness?
     
  3. Rod Back

    Rod Back Member

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    Does it on 1/8" and 14 gauge metal. On the 1/8" material, I'm running a 40 amp nozzle at .05 cut height and 100 ipm.
     
  4. LECS-Chad

    LECS-Chad Guest

    Your cut height seems low. I think on a FC80 the CH is .08. Also verify your AUTO being on and SAMPLE VOLTAGE ON.
     
  5. Rod Back

    Rod Back Member

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    I tried cutting at .08 on the height, but it created a small bevel on the edges. So, I lowered to .05 and created a straight cut edge. I was wondering if it is created from the mill scale on the surface of the plate?
     
  6. Dnmeistr-LECS

    Dnmeistr-LECS Well-Known Member

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    Have you tried spraying the shield cap with anti splatter spray, maintain the correct cut height (.08) and slow your speed down to alleviate the bevel.
     
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  7. Rod Back

    Rod Back Member

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    I will try those and see what happens. Thanks for the info.
     
  8. DanGeorgian

    DanGeorgian Well-Known Member

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    try .07 or .06 as well. my recommended cut height for 90% of stuff is .06 (which in my case isnt enough time for the avhc to adjust). and same as you .08 gave me the bevel. so i run at .07 and have 0 issues. these machines are super sensitive (note all your measurements are .000 not just .00)
     
  9. Rod Back

    Rod Back Member

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    Thanks, I'll try those settings and see how it works out.
     
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  10. No Class

    No Class Member

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    I have experienced the same scenario you described. I have found a good cap cleaning and some anti spatter help a bit but ultimately a small cut height increase is needed to be sure.
     
  11. Rod Back

    Rod Back Member

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    Does the height increase affect the cut? I lowered the cut height to .005 on 1/8" metal to eliminate the bevel it was creating. Even at a cut height of .008, I'm still getting the build-up of material.
     
  12. DanGeorgian

    DanGeorgian Well-Known Member

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    ya my bevel is less than desirable as well....
     
  13. LECS-Chad

    LECS-Chad Guest

    Conventional air plasma has an inherent 3-5 degree bevel.
    Keep in mind the plasma beam is shaped like a football so adjusting the height and making sure your speeds are correct gets the best results.
     
  14. DanGeorgian

    DanGeorgian Well-Known Member

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    when im at the scrap yard im seeing cut sheets anywhere from 1/4" to 1" and they dont have any bevel. depending on the part ill get a few cuts that are nice and straight but the majority still has a bevel. and the thickest ive cut so far is 1/2". but im getting less than desirable bevel on anything above 1/8"
     
  15. No Class

    No Class Member

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    The pieces your seeing at the scrap yard are likely cut with a $750k laser at ridiculous speeds and insane accuracy. I watched a 4kw laser in action last week and they are impressive. Edge angularity is a compromise that is made when cutting with an air plasma system. Anything over .250 thickness I achieve best result with book settings at 85 amps using a Hypertherm PM 85.
     
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  16. DanGeorgian

    DanGeorgian Well-Known Member

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    ya there is some laser stuff too. but you can clearly tell the difference between the plasma cuts and the laser cuts. these guys are getting really nice plasma cuts. i get having a little bit of bevel but imo i have more than the tolerance should be.
     
  17. Dnmeistr-LECS

    Dnmeistr-LECS Well-Known Member

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    Bevel should be equal on both sides /\ if you have |\ where you have straight on one side and beveled on the opposite side then that would indicate that the torch is not perpendicular to the material.
     
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  18. jimcolt

    jimcolt Member

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    Not all plasma's are the same. Using the right power level and set of consumables as well as correct speed and height and you can achieve 1.5 to 2 degrees of bevel on materials 3/16" and thicker, on thinner materials the bevel angularity will be more, but difference between the top and bottom of the cut less, this with shielded air plasma. With a HyDefinition class plasma using oxygen on steel you can hold about 1 degree on materials thicker than 3/16" and 2 to 4 degrees on thinner. The thicker you cut, the less bevel. Above about 1/4" a HyDef plasma will cut much faster than a laser and with smother edge quality and similar bevel. Jim
     

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