Thread: One little big job

Originally Posted by Marc

Well... I am sure you mean well but... going slow whilst welding a pipe is a guaranteed hole in one.
Which brings me to today's question...
Who has a pulse control on his MIG?
Is that something you can ad on?

blowing holes, so many answers and variables there... angle, speed amps, wire speed etc etc mate all I can say is practice practice and practice.

Originally Posted by Marc

Well... I am sure you mean well but... going slow whilst welding a pipe is a guaranteed hole in one.
Which brings me to today's question...
Who has a pulse control on his MIG?
Is that something you can ad on?

A machine comes with it built in. You can,t add it on. At this point it is not something that will improve your welding on thick materials.

Are you still on .8mm wire.? Thats the point we work from and set up some parameters.

Is there a digital read out on your machine?.If so, it is then just a matter of sorting out your technique.Can you read both amps and voltage of the read out if have a digital display?.

18 volts at 6.3m p / minute of wire feed is a good start for your vertical up setting if there/s no digital read out.

.Press trigger and measure what comes out ,say, in 10 seconds. Multiply by 6 for answer in metres p / minute.

Grahame

Hi Marc, I have never done this but it was covered in the tafe structural modules as acceptable splices in UBs, with a butt splice, do your weld prep for full peno (bevel etc) and do the weld, in your case go vertical up for the strength as you can't do it downhand. Then cut a square plate and weld it to the beam with the sides of the square on a different plane to the butt weld. I have attached a quick drawing to show what I am talking about. I am sure Grahame or others can confirm this method.

Ben

Attachment 113735

Graham, I am half way my 15 kilo roll of .9 wire. I cant believe how much I have welded already. That fence I am building is a killer. 2.4m pannels 2.1 high weight easy 80 kilo each pannel and I am shuvelling them around on my own. This weekend I have almost finished the gate. Lots of welding there. The gate turn out OK because I could weld it downhand. I made a real mess of welding vertical a 2 meters long L profile 25x5mm onto the 65x65x2.5mm post already in the ground. I tacked it on Ok then figured it was a waste to weld it al along so did some 100mm weld, 200mm blank and then another 100 mm weld and so on.
Lots of grinding I must admit. But I was also tired after 6 hours of working non stop and the light outside was fading. That is my excuse anyway. it's not that the rebate for the gate is going anywhere in a hurry, just looked rather ugly and needed dressing up.

To your question. I don't have a digital meter but it is something I can ad-on. I thought it would be handy to have. I'll see to get it done this week.
The settings have two knobs that read something like voltage setting 1to 4 and fine settings 1 to 4 as well.
I welded downhand a couple of 30x5mm flat bar, can't get any easier than that... and turned out perfect first go, on 3 for the first knob and 2 for the fine setting wire speed around 6 (Not measured but from the setting) and gas at something like 15 psi.

Ben, thank you for that diagram. It makes a lot of sense to add a reinforcement to the vertical section of the beam. I'll buy more offcuts from the steel place in Marigold Street number 20...what is it...Elton Steel or something in bankstown, and practice vertical welding on 8mm. I am sure I'll do well on thick steel.

Now correct me if I am wrong but If I weld the beam right. The strenght of the weld should be equl or stronger than the beam itself, in theory anyway, so If I need to patch it up, that means my welding is no good and the patch may be just as bad. (?)
The beam is 250mm high by 150 wide and is made of 8mm plate. The cantilever addition is 350mm on one beam and 600 on the other and they will hold up some 1000 kilo each max.

I have a question on vertical weld. I had to weld that 5mm L profile on 2.5 square pipe. I understand that different thickness provide and extra challenge
I understand that I have to go up and not down and that I have to go on an flat inverted V, fast in the center and slow at each side.
Now in a downhand situation, the more heat I use, the flatter the weld and penetration. Easy. Yet on vertical, the gravity is not helping me and all i get is some horrible thick fillets sticking out and not a nice flat weld. I thought in cranking up the heat and do some short goes stopping and starting.
I had another thought. What if I get a powerful electro-magnet that replaces gravity and flattens my weld?

Hi Marc
To answer your question
"Yet on vertical, the gravity is not helping me and all I get is some horrible thick fillets sticking out and not a nice flat weld."

The pause at the edges is like a (counted in your head) 1,2, and then flick over to the other side..Maybe you are staying too long at the sides.

THE INTENTION IS TO DEPOSIT THE BARE MINIMUM THAT CAN BE LAID WITHOUT A SAG OR DROOP.That is where you need to improve the technique.

Wire speed can be increased slightly in certain situations to create a cooler area by adding more volume which dissipates heat quicker- but only very very slightly.
I suspect also there may be a problem with the wire stick out. For what you are doing 10 -12mm is adequate. Wire stick out is measured from where the wire leaves the contact nozzle. The adjustment is made by yourself in controlling it.
Hopefully you have the volts / amps thing sorted.


Grahame

Originally Posted by Marc

3 for the first knob and 2 for the fine setting wire speed around 6 (Not measured but from the setting) and gas at something like 15 psi. These are the settings we are starting from

Along with improving your technique. If we use 1-2 as a pause, the time across from one pause point to the next is 3 as in 1,2 move3 ,pause1,2. In other words the time between pauses ,is the time it takes to say 3.

This is all done with a stick out of 10mm or so.


Now correct me if I am wrong but If I weld the beam right. The strength of the weld should be equal or stronger than the beam itself, Correct What if I get a powerful electro-magnet that replaces gravity and flattens my weld?
Because you are using DC current weld with the electro magnet will cause problems ,you will not believe. Not a good idea,trust me!

The wire you have is ok,

The attached beams aren't taking the weight I feared they might have to.

We can improve you technique ,so its all good .

We can do this .
Heres a graphic I have used elsewhere ,but I am sure it will help. It applies specifically to the pattern in vertical up welding.



Grahame

Hi Grahame, thank you for that...the big magnet was a joke of sort. I wonder if someone has tried for say overhead welding?

I thought a bit more about my work on the weekend...unfortunatley I did not bring the welder back to practice at home...I think I dont go up as fast as I should. May be I go over the weld too much.

Regarding the voltage dispaly thingy, I rang the supplier and I'l get it done next week. Must bring the welder back to install it. I thought it was a plug and play thing. Not cheap either. It's OK though, I don't mind spending money on toys.

Another observation. Whilst I was welding vertical up L shape 5mm to 2.5mm I tried to lower the heat down to 2/4 then 3/1 and changed the speed of the wire up and down a tad. Yet I never got a good setting. Most of the time the welder's crackling noise would fade and I could see the wire getting red and burning back. I tried to get the torch closer and it improoved a bit. I think I was holding the torch upwards and at some 45/50 degree from vertical. Is it possible to weld vertical up yet hold the torch facing down a bit ...say 100 degree from vertical?

Hi Mark, Your torch angle should be around 5degrees bbelow horizontal. I think the problem you had welding the'L' was due to the material being to thin for V-up.V-down would have been fine. Try lowering your settings while you are learning the technique of V-up. This will alow you more time to weave. If you have a weld that is high in the centre thats usually from not pausing long enough at the toe of the weld.
Cheers, Col.

As far as wire angle goes ,you want the angle of the wire pointing up. At least 10 -15 degrees above vertical.

It hinges on short stick out and avoiding the sag in the guts.
this means nil time in the middle.

Pause

Flick to the opposite edge - using short stick out.

" I think I dont go up as fast as I should. "

Fast as in the context of side to side-not the climb upwards - other wise
you will end up as in graphic No.1.

Grahame

[QUOTE=Grahame Collins;1017353]As far as wire angle goes ,you want the angle of the wire pointing up. At least 10 -15 degrees above vertical.

Yep, pretty well sayin the same thing. I tend to vary wire angle but I wouldn"t go any more then 15 degrees as I would have thought you'd start to have problems with penetration?

Originally Posted by Marc;1017291

Another observation. Whilst I was welding vertical up L shape 5mm to 2.5mm [COLOR="Red"

I tried to lower the heat down to 2/4 then 3/1 and changed the speed of the wire up and down a tad.[/COLOR] Yet I never got a good setting. Most of the time the welder's crackling noise would fade and I could see the wire getting red and burning back. I tried to get the torch closer and it improoved a bit.

Heat(voltage) settings on all machines would be lowest at 1/1 setting and highest at (pick the highest numbers on your coarse and fine settings)

Tuning , is arrived at by estimating the heat value you may need -setting the rotary numbered voltage switches, and then dialling your wire feed until it gives the highest audible pitch sound (its very distinctive)
The sound peaks at the optimum point and decreases as you go past it.It should be relatively easy to reach that optimum point.

Each combination of coarse and fine settings has its own audible sweet spot which you find by this method. I hasten to add this noise occurrs only in the lower half of the adjustable range (which is what we are seeking). At the top end of the range the noise is like a hiss.If you are set at that range, the whole lot will glob up on you as it is far too high for positional work.


If the noise decreased and the wire glowed red, it sounds very much like too much wire feed for the coarse /fine voltage setting.In other words , the wire is coming out at such a volume, the voltage setting is incapable of providing the heat to melt off the wire.


To clarify the angle ,the point of the wire is above the horizontal not vertical (sorry) by 10 at least degrees.

Grahame

OK, I am getting something now.
So I can guess the voltage by previous experience and say...5mm will need 3/2.
Then set voltage at 3/2 and fiddle with the wire speed until I get the fast/loud crackling noise. I can achieve this by welding downhand on anything else, say some scrap...right?
Once ready I go and weld vertical...?
On the torch or rather the wire angle. 10 degree below horizontal (vertical?) my wire was easy 40 degree below the horizontal.
Above below, I made a mess...If the welding point of contact is the intersection of X and Y and my torch in in the forth quadrant then the wire is or rather should be -10 degree. How do you make those sketches?

Can you tell me why do I have two copper nozzles for the torch...one is 22/50 and the other is 40/50 I think. I am using the smaller nozzle. What's the difference?

To your diagram. The way I was moving the torch is best described as an inverted U. I am so used to do the figure 8 or the little spiral with the rod that I can not help myslef. I understand now that it is slow and up on each side and fast and horizontal through the center.
In the case of different thickness I suppose I stay longer on the thicker material than on the thinner right?
As for the wire speed, you are right, I could feel the wire pushing against the plate.

Welding 5mm plate downhand I drag the torch and do a little spiral and the weld turns out as smooth as a baby.

Last question...how strong is this wire? Can you weld steel from say an old car leaf spring or will it crack. Do they make harder wire for harder steel like they make rods?

Hooroo
Marc

Marc,
You are saying that you think the settings should be around 3/2
which I read as coarse 3 and fine 2 .

From what i CAN OBSERVE FROM THE PIC your machine has 4 coarse settings and 4 fine settings.

My gut feeling tells me ,if thats the case the setting is too high and would normally be something like 2 /4.Coarse 2 fine 4.

Is there something else I have missed.?

Are you on a very long extension lead or is your GPO power down a bit ie not delivering a full 240 volts--maybe that needs checking- just with a multi meter.

Down hand manipulation and that used for vertical are completely different.
What works flat will not work climbing upwards - get used to it.

Sketches are with Microsoft paint- go to start >- programs >- accessories >- paint


will pick this up late - must go to work

Ok back again .

Going back over the settings if you were using coarse 3 it means your machine was set on what is basically 3/4 throttle.if you only have 4 coarse voltage steps .
For a big unit 250 amps that seems very high to me .Are you running from a 15amp outlet and is that outlet giving you full output? Possibly it needs checking.

This can be problem in surburbia in summer where grid demands often leave consumers with far less than the nominal 240 volts.From memory electrical authorities must supply with 10% of rated volts ,ie ,no less that 216 volts
It stands to reason if you are short on input current you will sufer the same on the machine out put side.

Food for thought.

Grahame

Unfortunatley CIGWELD in Melbourne is out of amp/volt digital "kit" and will supply me with one in September.
Will have to do with just number guessin for now since I don't have a multimeter.

In relation to my comments on settings, I may have muddled up the issue a tad.

My first welding job as you know is a security fence and gate that required a lot of small welding bits on square 65mm tube 2.5mm thick with some tack welding on 1.5mm for the 25mm square tubes all done downhand. Those are the pictures uploaded so far. For that I used like you said, 2coarse and 4fine and about 5 m/m for wire speed.
I also had to weld flat bar 30x5 and this I did with no problem on 3/2.
My problems started when I had to weld vertical up a 25x25x5 L profile to the post 65x65x2.5 Made a real mess of it.
I understand my angle was wrong at about 45 degree I still had the settings used for the flat bar at 3/2 but I increased the wire feed to 6.5 aprox using the logic that more material will allow me to go quicker up and demish the risk of burning a hole.
I did not burn any hole but got real bad penetration and a lot of very high and uneven fillets. Never achieved a continuous crackling noise and the weld was all over the place.

When you said to find a good balance between voltage and wirespeed/amps, I thought I could do so by setting it up on some scrap material and then go and do a position weld.
Are you saying that the position requires a different setting than downhand even when it is the same material to weld? So if I try a piece of 65x65x2.5 and a 25x5 welded downhand and set it all good, it will not work for the same material vertical? Bummer!

I don't have tension issues. I have a 32 amp powerpoint and made myself a 25 meter extension lead with 2core+earth, 6mm flexible orange cable. I got a wooden cable drum to wind the cable up, and installed a 32 amp powerpoint on the side plus a gang of 4x10 amp powerpoints for grinder, drill, light and radio all wired in with 6mm cable. I am good up to 40 amps 240V.
As for Integral energy cheating me and sending me dodgy current, I don't know. Will have to get a voltimeter for that. I'll visit the local cashconvertor and buy a stolen one to test it out.

I'll go up on Saturday and hopefully finish welding the plate for the lock and make up a decent striker and latch. My forge is still in peaces so it's all cold bend, hacksaw and weld. Fortunately my blacksmith leg vise can stand the punishment.