I have never been able to get fishscale looking welds with mig or
stick. Ny technique is to basically point the gun or stick at the
joint, anddo counterclockwise circles repeatedly.
Also, I have a terrible time getting 7018 started and runnign right. I
have alot better time with 6011. ANy advice?
--Instead of circles make crescent arcs back and forth; that's what
I've been taught anyway. The trick is to avoid having the heat follow a path
that crosses where it's already been.
--
"Steamboat Ed" Haas : Didja see my stuff
Hacking the Trailing Edge! : at 2010 Maker Faire??
Take some real welding classes, then, or find a real welder to tutor
you. There's a lot of welding that you can learn by doing, but there's
a lot more that you learn by watching an expert, or doing while the
expert looks over your shoulder and comments.
If you have a community college system where you live, take advantage of
it. You won't be sorry, except for the desire for better equipment at home.
--
Tim Wescott
Control system and signal processing consulting
You have received some good advice here to find someone who knows how, and
can SHOW you in a short time. "Stacked dimes" welds are over rated. They
are pretty, but, as the rod has to be whipped in and out of the pool, fusion
and penetration suffers.
With each joint, there are many variables ...... horizontal, vertical,
angle, how strong does it have to be, how thick is the metal, lots of
variables so it is tough to give you a one size fits all answer.
With a lot of my MIG, I don't do a lot of movement on thin beads. I like to
push the wire, and have an angle that gives a larger puddle that I can push
along, and up on to both pieces. When butt welding some pieces, and doing
pieces that are going go be visible, I like to do a series of spot welds, so
it looks like TIG, and only has to be hit with an electric wire brush.
Most of the time, if you are doing a wide enough pass, it is good to use a
weave instead of a circular motion, pausing at the ends of the W's or C's to
melt the parent metal for good penetration and strength. Just don't stay
too long, or your puddle will fall, as with 7018. Or you will burn through.
Ah, 7018. As Iggy can attest, it is frustrating at first. The key to 7018
is a short arc, trying never to whip out of the puddle, as you can commonly
do with 6010 and 6011 and come right back to it. 7018 is almost a submerged
arc, as you want to keep the point of your rod under the slag cover. To get
started on 7018, get some thick steel, crank up the heat to the max stated
for the rod, and weld in the flat position. At first, just make straight
lines, with a slow STEADY forward movement and no side to side. Pause when
you first start to get a puddle, then slowly and steadily move in a straight
line, with the goal to keep the size of the puddle the same, and when it is
reached, to slowly move ahead in one steady nonstop fluid motion. No in and
out of the puddle. Steadiness is the key, as it is easy to break the arc,
and then you have to clean it off, start again ahead of the weld, and bring
your puddle back to the end of the previous one.
As stated, someone can show you all this in a session, whereas thousands of
words here might not convey the "aha" moments.
Good luck. If you can weld with 7018, you get to say you know how to weld.
When you can run it vertical uphill, you get to brag a little. <g>
Steve
Visit my site at http://cabgbypasssurgery.com
Tim Wescott wrote:
If you have a community college system where you live, take advantage
of
it. You won't be sorry, except for the desire for better equipment at
home.
HA!
I brought my own machines to class. Theirs were much better but mine
still worked.
After learning how to weld them I tried it with solder, on the RF
filter cans for a satellite terminal. There wasn't much difference in
technique and results, though I could cheat and lift the iron out of
the pool. Maybe solder is a good reuseable substitute to practiced on.
...
I learned 7018 from an expert, and it went well right from the start.
The highly stressed and oil-tight tubular support frame for my
hydraulic bucket loader was the first project.
jsw
One thing I noticed.....
My dad just bought a new gooseneck trailer. Looking at the welds, they
were uggly! No fishscales and irregular welds everywhere. I guess a
weld does nto need to be pretty to be strong.
One thing I wanted to ask. Your comment on moisture and 7018 got me
thinking. I dont have an oven to put my electrodes in. They are in one
of those screw on tubes you buy from the store. Could I by a cheap
toaster oven. ( I think that is what they are called). nd bake them in
that? It would take up a minimal amount of room. Can you make them
more than once?
Rod ovens are not that expensive if you look for used ones. I bought
my first oven (10 lbs) for $20. It served me well, but could not hold
enough rod. I recently bought a 50 lbs Keen KT-50 rod oven for just
$75, brand new.
i
Your best bet is to light one up on a piece of scrap steel...if you
get porosity/cracks then you're going to need to dry them before use.
Do you have an old propane grill sitting around? That might be a good
source of heat for drying them. You will either need a thermometer or
a tempilaq stick to better judge the heat of the drying rod.
Well, is this to say old 7018 is usless if you have no way to reheat
it? Cant use for a trailer build?
reply: The problem comes from just as strong concrete weakens with
freeze/thaw cycles, 7018 deteriorates from wet/dry and freeze/thaw cycles.
If you find some old 7018, you will probably see discoloration on it, or
white powder. Or even flux coming off. This is what causes the weld not to
be 100%. On some critical jobs, rod that is not directly from a sealed can,
or been transferred immediately upon opening the container to an oven and
kept at a certain temperature may not be used. It is a good idea to keep
all rod in containers. Even MIG wire will rust from room humidity.
Steve
Visit my site at http://cabgbypasssurgery.com
All errors, brain farts, misspelled words intentional because this computer
is set to Spelchek French, and I can't get it to do any different.
Ive got a 10lb for $12, and a 50lb for $7 at second hand stores. The
50lb needed a new cord, and the 10lb didnt have one either, but it uses
standard computer cords, of which Ive got a shitload.
Took me 15 minutes to put a 15' cord on the 50 lber and 2 seconds to
plug in the cord on the 5lb.
Cant remember the brand..stroke moment..but they are bright yellow.
http://cgi.ebay.com/welding-rod-oven-hot-box-/120584245620?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item1c13619174
Ebay says both are Phoenix. brand.
The big one stands upright, the little on has feet on it so it sits
upright or at an angle. Both were filled with 7018,,,no..one had 30-40
lbs of 8018,....the other was filled with 7018
Gunner, dogged tired after working in Bakersfield in 100F heat
http://cgi.ebay.com/welding-rod-oven-hot-box-/120584245620?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item1c13619174
It's hit 100 in Ocala for the last couple days. The 'effective'
temperature was quoted as 115 degrees. :(
--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.
Get some 6013 electrode; it is one of the easiest rods to run. I still
can't run 6011 worth beans, but I can sometimes make a tolerable weld with
the 6013. If you really want to use 7018, get the Lincoln 7018AC rod, it is
a little easier to start/restart that regular 7018.
This all assumes you have a halfway decent welder, AKA not one that runs off
of 120VAC.
Jon
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