flux-cored wire size verses tip size

[twebb]

Hi,

I was recently watching a youtube video regarding mig welding with flux-cored wire. The presenter recommended using a tip one size bigger than the flux-cored wire (i.e. wire size 0.9mm use tip size 1.0mm).

Is this standard practice? Anyone else take this approach?

I welcome your comments and input!!

Thank you

 

[rtbcomp]

I think he's right. AFAIK tip sizes are only available for non-cored wire, ie 0.6, 0.8, 1.0 &c so for 0.9 cored wire 0.8 will be too tight.

 

[TechnicAl]

The tips are already bigger than the stated diameter. This one size above is an old wives tale, dont do it. The wire can arc inside the tip and cause electrical erosion which will at best reduce tip life but it can make the wire stick.

If a bigger tip was needed they would make them bigger, but its not.

With FCW you often use knurled rolls which marks the wire. If this marking is showing proud or the wire is "out of round" you have got too much pressure on.

Some manufacturers make 0.9mm or 0.035" (i think) otherwise you have no choive but to use a 1.0mm.

 

[digzdirt]

miller 211,using one size bigger tip for flux core wire

Just purchased an mm211 don't have gas yet,so I used the flux core, ,, well, ,,it SUCKED! lol. It got hot on all settings ,swelled inside the tip and stuck constantly,needless to say I was pretty miffed! I don't think the .35 tip. for. 30 flux is so far fetch.

 

[Robotstar5]

Just purchased an mm211 don't have gas yet,so I used the flux core, ,, well, ,,it SUCKED! lol. It got hot on all settings ,swelled inside the tip and stuck constantly,needless to say I was pretty miffed! I don't think the .35 tip. for. 30 flux is so far fetch.

Did you swap the polarity to suit flux core? and welcome to the forum.

 

[keith19]

Personally I find using a 1.0 mm tip with 0.9 mm flux cored wire perfectly fine, and certainly haven't had any problems.
This is on a Clarke hobby welder, mind. I've never used flux cored on bigger machines.
Usually the knurled rollers will very slightly misshape the wire anyway, because if they are set so they don't bite, the wire don't go thru. You can't see this very well until you use a magnifying glass, so it's very slight. But enough for a 0.9 mm wire to fubar a 0.9 mm tip in no time at all.

 

[philsmin]

I tried using 0.8 tips with 0.8 wire and had endless trouble with it sticking in the tip, I now use the next size up and it's fine.

 

[aametalmaster]

The tips are already bigger than the stated diameter. This one size above is an old wives tale, dont do it. The wire can arc inside the tip and cause electrical erosion which will at best reduce tip life but it can make the wire stick.

Yup i agree. The tips should be .010-.014 bigger inside than what is marked on the tip. I have read on countless forums about a bigger tip and prob a zillion times about a bigger tip for welding aluminum. I weld 10 hours a day with flux core and always use the same tip as the wire. If the wire sticks in the tip its usually another problem...Bob

 

[keith19]

"The tips should be .010-.014 bigger inside than what is marked on the tip."
Maybe hobby welder tips aren't made to that degree of accuracy, Bob. You are using pro tips on a pro machine.

I had problems using 0.9mm tips with 0.9mm flux cored wire. Constant sticking, even with new tips. This was on a Clarke hobby welder.
Soon as I started using 1.0mm tips with 0.9mm flux core wire the problems vanished, and haven't returned.

Like everything else, it's horses for courses, and what works best for you and your kit is what is important. Tips don't cost much, so it's cheap enough to suck it and see.

 

[dannyp]

i think the problems come with manuacturing tolerances.

i have used flux cored wire at work, large reels of branded wire run through the same size tip all day long without any bother,

tryed to do a bit of gasless welding with flx cored for a mate with his minimig as he was haveing problems and after 5 mins it drove me up the wall,

tryed the wire in my mig and it caused problems but with a 1mm tip and they mostly went away. so for the intrests in since took an empty small reel to work and wound some of the wire we use there onto it.

my conclusion - crap wire