Thread: Butt welding box section with the MIG

Originally Posted by Grahame Collins

If the edges were ungapped , grinding would just remove the metal placed on top of the surface with little peno beneath.

Hi Grahame,

I've been trying to butt weld 3mm thick RHS and did have a 2mm (or 2.5mm) gap. I am using stick not MIG. Today I tried bevelled edges with a smaller gap and the useful penetration (properly wetting both sides) seems much better.

I am using a 2mm type 12 rod at 50 amps. The bevel is the full thickness of the metal and the angle is 60 to 90 degrees.

Does this sound right or should I persevere with a parallel gap ?

Hi Steve,
Ah! practice makes perfect.

You know the old saying
"If its not broke don't try and fix it"

If you found a solution that works ,stick with it.
With stick the arc works a little differently from Mig.

Thats not to say however ,that with the right rod, the right amps ,arc length,travel speed and position you could not fill square butt edges on box sections.

The fly in the ointment is the travel speed.
It great to hear that its going well for you.
Cheers
Grahame

G'day.
When you butweld like that, does the finished joined length have a kink in it?

When I used a Stick welder I had the kink happen.
I haven't used the Mig to butweld yet
I am in the middle of building a Bitch's Box for our Pomeranian Bitch.
40x40mm and 20x20mm Duragal and 50x50 Gal mesh.
I have to join some 20x20mm tomorrow with the Mig.
So your post is extremely timely.

As a side note. I went and got a new cylinder of Mig gas M1 from Air Liquide. E size. Cost bloody $151 (not including rental costs). The last one I bought was in May 2006 and it cost $89.

What $ are you paying for Argoshield Light or Mig Gas?

Originally Posted by glock40sw

G'day.
When you butweld like that, does the finished joined length have a kink in it?
What $ are you paying for Argoshield Light

No Kink as I clamp each piece to something rigid and straight- another bit of box section would do. Tack in each of the 2 bloody corners- not like DH's photo- use a bit more voltage setting to wet it in- turn over -check with ruler for straight - tack and weld.

Tip -Dress the cut edges and take the paint off adjacent to the cut edge.

Without going looking for the receipt _ think $107 for E size A/shield light last October.

If you have heaps to do-make a jig.

Grahame

I drew the pic in MS Paint and have omitted the clamps as they would take too long.

Check all tube alignment with a ruler BEFORE any welding.
Its time to do some of the same myself.

Grahame

Hi I just wanted to add my bit on the gas.

I got a bottle of agroshield light size E last week from BOC cost $98.35 inc GST and by the looks the rental is $37.77 for 3 months.

Mitch.

hi graham
do you have a 150 or 180 kempi mini mig?
have been looking at getting one mainly gasless any comments would be helpful

Hi Supervisor,
I have a Kemppi MiniArc Mig 180 Adaptive. I am not all that enthused by the wire drive and feed system.In point of fact I am very disappointed with it given the purchase price.

The wire spool axle,for want of a better term is fixed. The spool encounters friction as it rotates. Very poor engineering given the fact that the machine is capable of welding aluminium.

The wire feed rolls look out of place on a $2000 welding machine.The are a bit of a tacky unit being mostly of plastic.Everything is downright fiddly. To change a liner took half an hour or better with no helpful instruction in the owners manual.The liner itself came with a sheet that explained it better.

I am afraid now that I have used the unit a bit its not the value that I had hoped for.I am a bit negative on Kemppi now, especially as I emailed them with my concerns.That was weeks ago and no reply yet.

I you have that sort of money and still want a compact unit to run fluxcore you might try Lincoln its half the price.

Grahame

Nice mini-tutorial Grahame thanks.

Interested to hear your opinion on the Kemppi's automatic setting... I.e. from what I see you just set your material thickness (and maybe even weld angle?) and it works out the best settings etc, or at least what it thinks is the best settings? How well does that part of the welder work in your opinion?

I think half the battle with newbie welders is trying to figure out the best settings for different thickness materials and weld positions?

Originally Posted by Dean

Nice mini-tutorial Grahame thanks.

Interested to hear your opinion on the Kemppi's automatic setting... I.e. from what I see you just set your material thickness (and maybe even weld angle?) and it works out the best settings etc, or at least what it thinks is the best settings? How well does that part of the welder work in your opinion?

Hi Dean
The machine picks the settings extremely well . But there is more in it than that.
A new welder should know that there are variables (angle,travel speed,stick out length, gas flow rate ),controlled by operator manipulation of the torch that can grossly affect welding outcomes and it is possible to stuff, in spite of the machine doing some of thinking. for you

The display does not recommend angles for welding but merely shows the fillet types that can be welded. Ie concave, mitre and and convex.

A good idea of what it does can be obtained by downloading the operating manual from the Kemppi site.

I am selling mine as I am not using it as much as I thought I would and am too tight to have $11 p/month on something I don't use.

Grahame

I agree with Grahame, I have seen a fair few tradesmen come through my workplace, and as every welder is different, it can take some weeks to fully come to understand the settings and foibles of the machine. We only have fully manual machines, and even then they seem to have more brains that the operator at times.

PS. Nice tutorial Grahame, I have used that method for some years now and the problem with kinking disapeared once I started.

hey graham how much you want for the kempi?

Hi Supervisor,

I reckon about $1400 and I toss in three new liners, and a 2 spools of steel wire and 1 of Aluminium

Grahame

does it come with a reg
how old and how much work has it done ?
and is the warrenty still valid?