I have finally got all my material and a 150A dual purpose welder and although only been playing a while the welds arnt great. It currently is running
in gasless mode and wondered if it would be worth changing to gas to get a cleaner weld? Also any tips what sort of power should i have it on?
[Edited on 19/10/02 by Gremlin]
argh!
this is such a big subject!
search on line for welding tips on google, this site, or on TOL.
Once you get the technique its not too bad. I managed to weld my car using a 100a welder turned nearly all the way up, so you have power to spare.
I havnt used a gassless mig, so i cant compare. However I suspect that as professionals dont use gassless (cost?) there might be a reason.
i would suggest that you look at the suggested settings in your manual.
if you dont have them, try some experiments on a sheet of 1.6mm.
set your settings half way, make sure the earth electrode is well connected, and strike a weld. Hold the torch at an angle of about 20 degrees about
10mm from the work. move the torch at an appropriate speed - which you will tell by the bead 'fatness' - likely to be about 5 - 10mm a sec.
move the torch FORWARDS so that you are moving in a direction where you are moving the wire into the work - not dragging it backwards. This matters.
Its also easier to weld flat than vertically.
Using the above guide, weld a 'snail trail' on the test plate. You should see the weld starting to come through the other side. If it doesnt, and the
weld 'sits' too high on the other side, you are either feeding too fast, have too low a current, or moving the torch too slow.
there are a lot of weld faults - you need a book or summat!
Once you get the bead welded, try and weld two flat plates, butted together. This is where you find how heat is a problem. At edges of metal, the heat
does not dissipate, and you get local hot spots. You might blow holes through. If this happens, turn down the current and/or weld intemittently.
Basically stitch weld an inch at a time and then come back and do the gaps.
Also try welding two bits of inch section box together on ONE side. then bend them apart and see how far your weld penetrated.
Like driving a car, its hard at first, then second nature afterwards.
read up a bit, and dont be discouraged at how bad you are at first. Just dont start the car until you can weld up bits of scrap OK.
Make sure you get a co2 and argon mix. Co2 on its own is more tricky and spatters a lot.
atb
steve
Gasless mig welding is a bit pants really. IMO get it setup on gas. Follow Stephens tips/suggestions and you will be well on the way. And a couple more tips...try not to weld in a draughty atmosphere, this will blow the gas away from the weld area and create a poor weld. If you have no choice, turn the gas pressure up and make a temporary wind break/shield. And when you come to weld your frame, clean the general weld area with some emery cloth or sandpaper before welding and brighten the steel up, even though you are probably going to be using brand new steel. It will make a difference, believe me. Just trying to burn though the light oil coating on the steel takes up unecessary power, and can contaminate the weld.
i agree with the stu,gasless are not a lot of cop,use gas and you will find it a lot easier to get good welds
I will add to the above advice, all of which is good,--
GET A SKILLED WELDER TO SET YOUR MACHINE UP AND TEACH YOU HOW TO USE IT!
The time it will take to you to do all that on your own will probably be more than the time it will take you to find someone to teach you. If you or
your friends don't know anyone, get a mobile welder to call.
John
What are peoples views on direction of welding. i can weld but i am not an expert, i have been taught both oxy and stick welding at college, but have
learnt mig myself. I have always dragged the torch while welding, not pushed as advised above. I thought that it didn't really matter, but i have
been told by an experienced welder that it is just a preference for some people when welding thin metal to weld forwards as the metal is cooler where
you are about to weld which reduces the risk of blowing through, wheras for thicker metal is necessary to drag or weld towards you as this increases
penetartion.
Therefor in my eyes isn't it bette to weld in a dragging direction as long as you aren't blowing holes so as to aid penetration? Anyone have any
comments?
I weld forwards and backwards to suit where and what i'm welding, and to my (admitedly non-expert) eye, there doesn't really seem to be a lot of
difference between the two.
John.
now i aint no expert but can get a decent weld on two good bits of metal i.e not a rusty old fiesta i find it more naturel to pull the torch towards
me but get a better weld if i work away from me
which i find is better for a long piece .start in the middle weld away for bout an inch then weld a bit on the piece at my side weld then weld a bit
on the other side of the first weld . i find it helps keep distortion down and by the time the two welds meet the first bit is well cool so doesnt
blow a hole
Regarding the initial question, you may have the welders polarity the wrong way round! Try it and see, it's the opposite if using gas. If I were you,
I'd use up the non gas wire, then invest in a bottle of argoshield light from your local BOC dealer - much cleaner welds.
Marcus
Hi,I've done a few courses on mig and tig and quite a few hours professionally and I struggle sometimes so dont panic.
Practice is the best advice !each time you do a certain type of weld practice the same type of joint first.Usually if it looks right it is.
You can weld backwards and forwards but pushing is better.You pre heat the steel in front and force the gas in front as well.This also has the
advantage of burning any impurities off first.
Welding vertical is easier downhand, especially on thin metal,mainly because you are moving away from the heat which is rising,stopping you burning
through.
Having said all that I bought an MK chassis,Martins welding is better than mine and it's easier to get on with the fiddly bits.
Dean.........
Yep, the text books say that you should push into the weld, but on thin steel pulling the trigger can avoid blowing holes, but it leaves a weld that stands a lot prouder.
Thanks for the advice. I have now converted the welder to gas and things are going much better although i seem only to be using half power if not less
for the 1" x 1" box is that about right on a 150Amp welder?
I think i will have to get someone to look at my welds to see how good they are and if they are up to scratch.
[Edited on 20/10/02 by Gremlin]
you should use as much power as you can without blowing holes through the work. You need a decent penetration as well as a pretty weld. As i indicated
earlier, a 100a welder just about does the job, so your 150 ought to have some in hand!
atb
steve
quote:
i seem only to be using half power if not less for the 1" x 1" box is that about right on a 150Amp welder?
do a night school course, im at college doing, restoration course, migs quite easy, compared 2 others, they do all types mig/mag-arc-oxyacetylene,
etc,,after a few hrs praccy at college ull be alright, trust me i was, thats sayin summit
Maybe this is obvious, but I didn't see any mention of it. The gasless wire contains flux. You should change the wire when you set up with gas.
Gasless wire is also much more expensive (2 or 3 times as much). Everything goes much nicer with gas unless you're outside in the wind. The welds are
much cleaner as well. The flux gets "soot" all over the bead. I have a 130 Amp MIG, and half power sounds about right. You have to play with it until
it goes right. The sound of the arc will be smoother without any spitting and popping. When you've got it right, you'll know. You may not know 'til
you get it, though! Keep practicing. Build a cart for the welder or some other project where a weld failure won't kill anyone. Do a lot of 3 pound
hammer tests. Take a big hammer and beat on your practice pieces to see where and if they break. I'm no expert at this. Just passing on what worked
for me. I also had trouble seeing what I was doing. I wear bifocals and couldn't line up the the helmet lens with the bottom segment of the glasses.
Single vision reading glasses made a world of difference. So does an auto darkening helmet if you can swing $100 US or so.
HTH
been over at a mates house this weekend getting some handy welding hints, he uses a 90amp gasless mig and gets some bloomin good welds, penatration is spot on and the end result is a damn fine join. Tried absolutely everything to get the weld to break but couldn't. the welds are that good that i've bought exactly the same welder... blinding bit of kit.
quote:
Originally posted by jasinuk
do a night school course, im at college doing, restoration course, migs quite easy, compared 2 others, they do all types mig/mag-arc-oxyacetylene, etc,,after a few hrs praccy at college ull be alright, trust me i was, thats sayin summit
I have gone MIG with argon shield and that seems to produce a perfect weld and very smooth finish. I had a friend come over to help me and now im much happer and am ready to go.
I have gone MIG with argon shield and that seems to produce a perfect weld and very smooth finish. I had a friend come over to help me and now im much
happer and am ready to go.
I tried gasless as my welder is duel purpose and although not bad nowhere near as clean as gas welded. Well thats what i found anyway may just be
me.
[Edited on 28/10/02 by Gremlin]