Stainless flux core problems.

[Hood]

Ok, managed to dig out the oven and shoved a reel in it overnight and tried it a short while ago.
A couple of things to bear in mind.
1. This was the initial reel I tried which gave me absolutely horrendous results, see first pic.
2. I don't think I had the temp high enough (dial is broken) and it was only in approx half the time that Bohler say of their fact sheet.

Ok so first pic is with my initial tests before I dried the wire.

This one is non pulse pull. Still some surface defects but I think that is likely due to me not being used to pulling with a mig as all my Mig is Aluminium normally.

This is non pulse push. Much better to my eyes but others may disagree. When I am saying push it is the same as I normally use with Alu so barely any angle at all.

I will be doing more tests with pulse if I get a chance.

 

[Dcal]

Thanks for sticking with this @Hood.
Great information here for us dabblers and there is so much more to learn from resolving things when they go wrong instead of dumping it and buying a new roll.
Looks great to me but I know nothing.

 

[Richard.]

The proven method for all FCAW is a slight drag angle. This is to keep your Molton metal pool at the front under the arc and the slag forming nicely in your tracks. Pushing can encourage slag to run in front where the pool is.
Trials are all good but unless your doing something very wrong the best results will always come from a slight drag angle.
A pulse is awful on fcaw. It’s just not the right type of transfer for it.
You get the best results from a just into spray transfer. So as soon as you break out of a globular transfer into spray your about there. On 1.2 fc wire it’s around 23-24v 7-8m/min. (180-200amps).
Perfect conditions for that wire.

 

[Brad93]

If you do a cut and etch and you’re pushing the torch you’ll find you’ve got a nice big slag trap at the root

 

[Hood]

Did a few more tests with pulse and super pulse just to see what it was like. Pulse was quite spattery, super pulse was less so but both harder to control than standard and not nearly as nice to do.
Tried a vertical up in standard spray and it was not too bad then did a weave over the top and again reasonable.

I think I will just be staying with the stick welding though as there doesn't seem to be any advantages of mig stainless for the things I do and probably a lot more disadvantages. Yes if I was doing big projects with long runs then mig would be the way to go, for speed especially, but most of my stuff on stainless is not like that.


I will give it another go both pushing and pulling with standard spray and do an etch, it will be interesting to see how they compare.

 

[Brad93]

There are huge advantages to stainless flux core over stick. You just need to be shown how to use it.

No point trying pulse or double pulse it’s not designed for that and pulse uses high voltage spikes which will just cause you loads of issues!

Don’t push you’re just wasting your time mate.
The definition of insanity is doing the same thing over and over and expecting a different result.

 

[Hood]

What would the advantages be?

Just to reiterate most of the stainless welding I am doing is short runs and nearly all outside on a boat and very rarely is there no wind.

 

[Brad93]

Some benefits.

• All positions on one parameter. Vertical, overhead, flat and horizontal can all be made in one setting. Usually 160-200A
• No cold starts or danger of porosity at the start of the run.
• Smooth weld appearance and easy release of slag.
• Smooth weld is a lot easier to clean and passivate.
• Better penetration than MMA.
• Higher productivity.
• Higher efficiency.

 

[Brad93]

If you’re outside then rods are your only option.

 

[Hood]

Yes, like I said I will stick to stick for the stuff I do

It is still interesting though to mess with this stuff as it is always fun to learn something new especially when it doesn't cost much (free wire) and you never know when it will come in handy.

 

[Richard.]

all outside on a boat and very rarely is there no wind.

That’s the real kicker in this
Welding outside with shielding gases on your side of the coast isn’t going to be much fun.
I’d be sticking with MMA for that too.
I love fcaw stainless steel. Such a lovely process.

 

[Hood]

It is the same old thing, use the process that suits the job you are doing.
I actually like doing stainless stick welding, gets a PITA below maybe 2mm but thicker and it is nice and I charge by the hour so ....
.

 

[Richard.]

Yes stainless MMA is a wonderful process especially with quality consumables

 

[Hood]

Yes stainless MMA is a wonderful process especially with quality consumables

Yes, used a lot of different ones over the years and currently I have some Esab ones which are very nice indeed.

 

[Hood]

If you do a cut and etch and you’re pushing the torch you’ll find you’ve got a nice big slag trap at the root

Gave it a quick go again earlier today and I had the worm tracks on the surface again so looks like it does need the proper drying procedure. Anyway did an etch and you were spot on

 

[backpurge]

By the way the weld has rolled I'd say your volts are too high which would also account for the worming

 

[Hood]

Quite possibly or could be my bad technique due to only ever welding Aluminium.
I never actually paid attention to the settings today as it wa just a quick test to confirm Brads thoughts.

 

[Seano]

Old idium (usually) If its got slag then drag" as it turns out I've just recently watch a video about worm holes in weld using FCW, they were saying that 1) Damp Wire, 2)Gas Flow, 3) Speed of Travel, if any of that helps hood.

 

[Brad93]

Old idium (usually) If its got slag then drag" as it turns out I've just recently watch a video about worm holes in weld using FCW, they were saying that 1) Damp Wire, 2)Gas Flow, 3) Speed of Travel, if any of that helps hood.

You’ll only have issues with gas if you’re running too lean a CO2 mix. 15 to 25% CO2 is required usually.
Or like with any other process you are well outside the allowable limits. 15lpm - 21lpm dependant on shroud size is required for gas shielded flux core.

Travel speed very unlikely to cause worm tracks. Incorrect travel speed is what causes lack of fusion at the root.

I would say it’s voltage which is the main cause of issues and even more so with stainless alloys.

 

[Hood]

Old idium (usually) If its got slag then drag" as it turns out I've just recently watch a video about worm holes in weld using FCW, they were saying that 1) Damp Wire, 2)Gas Flow, 3) Speed of Travel, if any of that helps hood.

Sorry, didn't see your reply.
I think the problem is most likely dampness, it sat in the boot of my car for quite a long time over the winter so it would have been cold and damp in there.
Gas was 15% CO2 so should have been fine and flow was 17-20 lpm.

Tried at all sorts of voltages on Friday and no difference except lack of fusion when I went too low. I think it just needs a good drying out as the difference between the initial runs and the subsequent ones after a short dry was night and day.
@Richard. is taking a reel off me to have a mess around with so we will see how he gets on. The others I will likely post on the forum for postage cost as they are just in my way and not really much use for the type of work I do, I was just curious to use it and see what it was like.