I'm a carpenter and I used to get my gate frames made
by a friend who has moved away, so I decided that I
would make them myself.
I've had an arc welder for a while and while I'm no
expert I'm reasonably competent with it.
The problem I'm having is that when I try to weld 25 x
25 x 1.6mm square tube I sometimes blow holes in it.
My solution has been to use 2.5mm tube, but this is
more expensive and not really necessary for the
application, so I'd like some information (Advice,
Links etc) on how to successfully weld the lighter
I'm using general purpose 2mm rods, and my welder
doesn't have an amp scale but has a gauge to match
rods with material and I've experimented with a lot of
amperage settings but can't seem to get a good clean
weld on the thinner stuff.
I have no problems with heavier stock.
Any help greatly appreciated.
1.6mm is 16 ga (.062") on this side of the pond. I'm assuming you are
trying to weld an end of one tube to the side of another tube. This is
relatively thin tube, you will always have trouble with the end cross
section burning away on you.
A few suggestions: joint prep is critical. Since you aren't an expert
welder, spend your time on the prep. The joints should have no gaps, the
cuts should be square, there should be no sharp edges that will melt too
quickly. Use 6013 rod (not sure if you can get that exact variety). It
is designed for thin material, minimal penetration, easy slag removal.
Experiment with the amperage selection. There is a setting that will
give you the best compromise between the penetration you need for
strength and the excess heat that blows holes. The exact setting is very
much a function of the specific welder used and the specific weldor skills.
OK, the punch line: PRACTICE!!!
Neil Green wrote:
You are essentially trying to stick weld sheet metal, which is a
chancy proposal at best. This is a really good reason to upgrade to
a MIG welder - there you can just look up the setting for 16 ga. and
weld all day long.
You can run stick a lot cooler if you try running it with the polarity
reversed from the way it normally is. Try running DCEN instead of DCEP,
that may help. There's some rod that this works very well with, but I
can't remember it offhand, nor do I do this dodge myself, having other
Sheesh! Why not just suggest getting a TIG welder? (Sarcasm!) I can
teach most anyone with a steady hand and a willingness to learn and
practice how to stick weld this project in 4 working hours (spread over
several days) Clean metal, good fitup, proper rod, downhand welding,
and a buzzbox with reasonable OCV and you can easily match a MIG weld.
OK, I'll grant that you will have more spatter to deal with.
The 16 ga 1: tube the OP is talking about is a standard construction
material for building theater set frames at our local theaters. Chop saw
to get clean SQUARE cuts, weld away. They do hundreds of joints in a
complex set with multiple tiers.
Bob Engelhardt wrote:
This sounds like the frames are for professional work that you do. In
which case it's worth it to have it done right. You will never get it
done right with your stick welder and being "reasonably competent".
Finishing a whole gate without burn throughs will be impossible. Burn
throughs are ugly and would give the whole gate an unprofessional look.
I've 2 suggestions:
1. Get a small MIG & learn how to use it(!), or
2. Pay someone to do the welding. This might be done pretty cheaply if
you do all the cutting/fitting and take it to him all jigged up, so he
only has to weld.
Thanks for the advice Roy.
I have a cutoff saw so the cuts are square, I guess it
is just a matter of practice.
The rods you suggested are 2.5mm from what I've been
able to discover.
I have some of these but I've been using 2.0mm.
Would I be better to use the bigger rods?
Also, are any particular type of rod better for this
work than others?
The type I have are general purpose, I bought them
from an engineering supply so I presume they are of
Thanks for your help.
"Bob Engelhardt" wrote in
Thanks Bob, but the main disadvantage to having
someone weld the frames is that by the time I cut
them, take them somewhere to be welded then go back
the next day to pick up the finished job it wouldn't
pay as far as my time is concerned.
When my friend lived close by this wasn't an issue.
As I said I have no trouble using 2.5mm square tube
but it's more expensive and not necessary for
I'm fairly sure that the 1.6mm material can be
successfully welded with a stick welder, I just have
to learn how.
6013 is the type, not the size, they come in many sizes. It should be
available in 5/64th (2mm). You may even find it in 1.5mm (1/16th).
That said, you may find the 2.5mm will work just fine--I've found the
smaller rods can actually be harder to control, sometimes. You may
also want to
try the 7014 type rods.
If it's a better type for the work you're doing, sometimes the size
doesn't matter as much. If you already have some on hand, it's worth
trying. Start with the amperage selection listed on the package and
go from there.
As glyford mentioned, 6013 is the type or spec on the rod, not the size.
You don't mention where you are at so I'm not sure how that will
translate to local suppliers. The 6013 has a very soft arc, is not at
all aggresive in 'dig' or penetration. It was original developed for
thin sheet metal applications. When properly done it leaves a nice soft
slag that sits on top of the weld.
out page 16 of the catalog and bring it to your welding supplies
I'd be concerned with your "general purpose" rod. The other common rod
(read CHEAP!) rod is 6011 which is good for rusty or poorly cleaned
metal and has the necessary 'dig' to get through the rust. This rod will
burn through like you have been noticing. You could try a test: run a
nice bead on the side of a piece of scrap tube. Try for a very even,
almost fat bead. After it cools, examine the slag. If the slag is dark,
a bit porous, and completely covers the weld area, and chips off with
one tap of the hammer, it is likely 6013. If it is glassy or shiny, does
not cover all the weld area, and has to be tapped several times to
remove, it is likely 6011.
When you weld an end to an edge, focus the rod more to the side of the
long tube and away from the edge end of the other tube. If you have a
weld that involves one end out in the air, start on that end (on a gate
that usually means weld form the outside to inside) since the coldest
part of the weld is at the start. Try to weld everything downhand. Run
your current as low as possible consistent with keeping a clean arc.
Keep the arc short.
Practice Practice Practice! Figure it will take several total hours of
practice over several days or a couple of weeks to master the eye hand
coordination needed. You will need to burn a couple pounds (or 1 kg) or
the smaller rod to really get the skill level up.
Neil Green wrote:
I'd agree. Stick seems more suited to heavy structural welding than
light tube frame work though I'm sure the pros can do it. I'm not pro,
but frequently my welding projects are made with 16ga square tube in
1/2" - 1 1/2" sizes. I TIG weld it and rarely have any problems.
As has been suggested, try a 7014. It's very forgiving and tends to look
good even if you didn't run a perfect bead.
Run hot and fast. Traveling slowly causes the heat to spread along the
surface of the metal, that's where you get the big holes when the puddle
falls through. Keep a short arc, just as short as you can, and know
what you're going to do before you do it. Lean on something so you're
as stable as possible and turn the work so it fits your natural motion.
You should be able to run this weld with a 6011 too, try it on AC. Try
the 7014 on AC too..
And keep at it, you'll get it.
It's not so easy (at least for me) I built a light trailer frame from
25 x 25 x 1.5 mm and had the same problems you outline. What
eventually helped was 2mm 7014 rod, a short arc and a fairly high feed
rate. But most important was about 2 hours of practice spread over the
best part of a couple of days.
Best of luck (but practice will be better than luck !!)
"Neil Green" wrote
I was a steel erection contractor for nine years. In that time, I repaired
a lot of thin walled tubing on gates and fences. I used 6011 3/32" rod
exclusively, BUT, used it against suggestions with electrode NEGATIVE. If
you can dial down your welder, you can run it, but it takes time getting
that fine touch required to carry a small puddle, or "stack dimes" with a
Since you're in another part of the world, I don't know what the conversion
factors would be, but you should be able to find those out easy enough.
For a pound of rods, try it. It might just work for you.
"Neil Green" wrote in
Thanks to everyone for the expert and practical
advice, a very helpful group.
I'll score some of the rods recommended and give them
I was buildin a fence and gate for an apartment complex with my job.
Trust me I know what you are goin thru, my boss showed me the trick
for it though and it works like a freakin charm. What you do is turn
your amperage down a bit and make a series of tack welds. Just one
after another, kinda overlapping them. Make SURE you do it to where
they are GOOD penetrated tacks, but dont stay on there long at all.
After you have done this across the joint you are welding, crank up
the amperage then go back and make a good strong weld over the tacks.
What thats gonna do is melt all the material in together and you
should have a good strong weld without having punched thru the metal.
This works, trust me, my boss didnt believe in mig welding in the
field, all we burned was the big Miller Gas engine welders and 6011
rods. It will do the trick for you. We built fences, gates, handrails.
Hell we did it all with stic welding. Good luck bud.