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stormbird
05-19-2010, 09:03 AM
Hi all

I have just bought a R-Tech TIG160 in MMA mode [SMAW mode ] my first tries at stick welding with it.

These pictures are after burning about 24 rods and coming down from 3mm plate to 1.5mm.

Well more practice trying to reduce the current , laying the rod further back and doing a circular weave all seem to help a bit.

Pic 1 1.5mm x 35mm box laying beads as long as possible did first few then swapped sides
did the same on otherside then swapped over again and finially finished on this side again

Pic 2 whoah getting somewhere I think 25mm square 1.5mm chrome plated [ the red is a reflection of my hands ] I think this looks a lot better than first attempts above.

Pic 3 back to the inside weld , still poor but not quite as bad as first attempt , I could hear the noise the weld makes when it had penetrated the other side , but there are no holes visible.

I was welding the the rod maybe only 30' from horizontal and felt I could also feel the rod sort of pulsing as it touched the plate ? or was that nerves ?

The rods are now getting harder to start as the current goes down , first time is ok then they are hard , I think I saw somewhere that someone had a file on the welding table and they filed the end of a used rod to help it strike

Really all my starts are poor I think I need to go back over them and circle a bit before setting off down the bead ?

I think I am still too fast on the flat beads and maybe not enough current for the inside angle ?

How come I can lay a 6" bead on the box when practicing and then fall apart when I try to join two pieces of it together ?

pointers welcome :dunce2:

regards Paul

John Lewis
05-21-2010, 06:15 AM
Just looking at the welds. The first ones don't look too bad. You seem to have got some penetration and the bead looks OK.

On the angle bit it seems you have not got into the corner. The weld seems to be each side of it. The bird dropping look suggests not enough heat. Try turning the current up as far as you dare. Do a half inch or so then stop. Let it cool a bit then start back a bit on the previous bit and do another little bit and so on. You need to try and see the weld puddle and make it go where you want it to .

Practice. Don't be afraid to blow some holes. You will get the knack soon enough.

Edit: One more thing I thought of. You haven't by any chance switched the leads between the different welds? That last one looks like when I set up the welder with - and + reversed.

John

stormbird
05-21-2010, 10:25 AM
John

As you suggest I think I am to close to the cold side , I think you can get away with that just laying beads onto flat sheet but not when you try to weld any sort of joint.


Do a half inch or so then stop. Let it cool a bit then start back a bit on the previous bit and do another little bit and so on.

Do you remove all the slag before going back and doing another 1/2" ?

I have some fair quality Parweld rods and on the box they say 40 - 70 amp which I thought was a little low on amperage ? I understand my welder is only guessing at the accuracy when it tells me the amps I have it set to [ can't see the display whilst head dpwn and welding ! ]

I understand some rods can be either Stick + or Stick - ? these do not say on the box.

I always set the machine up Earth - , although I have a video [ not watched it for a while ] which says there is less heat in the metal one way around , I think that is Stick + how I currently use it.

No substitute for practice , so back to burning sticks.

regards Paul

Locutus
05-21-2010, 01:21 PM
Try using 7014 rods. Might also want to try thinner rods. Harbor freight has them in 1/16, 3/32 and 1/8.

badcheese
05-21-2010, 06:50 PM
The rods are now getting harder to start as the current goes down , first time is ok then they are hard , I think I saw somewhere that someone had a file on the welding table and they filed the end of a used rod to help it strike

After running a bead, a little bit of flux will form a crusty tip on the rod. The trick I use for easily striking the arc again is to just snap off the little bit of flux at the tip with my gloved fingers, assuming the rod has been cooling for several seconds since running the last bead. I can just pinch the very tip of the rod and snap off the flux residue with a bending motion. That will only break off the melted/rehardened flux that is preventing me from striking another arc, while leaving the fresh flux that I want to keep. If you do it too soon after stopping the previous bead, you will burn through your glove, so give it a few seconds to cool down.


How come I can lay a 6" bead on the box when practicing and then fall apart when I try to join two pieces of it together ?

This happened to me too. The arc would wander between the two pieces I was trying to join, so instead of a single bead joining the two pieces, I had a bead on each side of the joint and a gap in between filled with flux. I had better luck when I stopped trying to maintain the "proper" arc length, and just brought the rod down so it was dragging lightly in the joint. As long as I keep enough angle, the unburned flux coating prevents the rod from shorting against the work piece, and I get a single bead joining the pieces.

badcheese
05-21-2010, 06:57 PM
Try using 7014 rods. Might also want to try thinner rods. Harbor freight has them in 1/16, 3/32 and 1/8.

Yes, a thick rod will tend to stick when you weld at a current lower than it was designed for. When you weld thin material (low current), you need a thin rod. My local welding supply house doesn't even carry 1/16 rods, so I go to Harbor Freight. 7014 seems to give good deposition with less penetration than 6013, so it's a little easier to weld thin material without burning through. Notice I said a LITTLE easier!

stormbird
05-22-2010, 12:49 PM
Hi there

Thanks guy , nice to see these are just beginner problems.

7014's are as rare as rocking horse droppings in the uk ?

I am using 2.5mm rods [ 3/32 ] I understand thinner rods just give you more flux and less filler ?

regards Paul

John Lewis
05-23-2010, 04:18 AM
John

........... I think that is Stick + how I currently use it......

regards Paul

Yes that is correct for stick. TIG is reverse.

John

stormbird
05-24-2010, 03:48 PM
Hi all

Just been watching a Arc welding video and noticed the rod was being used differently ?

I have the rod running parallel to the direction of travel , and the video showed someone holding the rod at right angles to the direction of travel , is this important ? I never really though I may be holding it wrong.

regards Paul

John Lewis
05-26-2010, 01:24 AM
Reply to a previous question. Yes Do a bit. Chip, then a bit more etc.

I lean the rod along the direction of travel so my hand is leading the rod. Then I move the rod away from the puddle. That is I pull the rod not push. Talking stick welder here.

The angle the rod makes with the work will increase or decrease heat and penetration I think. The more vertical the rod the more chance to blow a hole. I seem to lean my rods around 60 degrees most times. There is probably some "perfect" angle but I don't know what it is. Trial and error is your friend when learning. Use high and low current. Burn holes.Fill them. Try different angles. try the rod at different distances from the work. Take note of the effects and make adjustments. Practice and more practice.
John