A master class in welding through boards

Greengrass1

Welding comp coming up in macra. Might throw myself in for it if no one in the club is interested.
Can weld but it's only repairing jobs etc and it definitely looks rough and if it does look good it's a pure fluke.

How do I decide on what amps etc to put welder on? Steel size?
How does one do a very clean weld ?

Nekarsulm

https://m.youtube.com/results?q=arc%20welding%20tips%20for%20beginning%20welders&sm=1

Search for "arc welding" or "stick welding" on YouTube. Or go to a fabricator and ask for a few lessons or tips.
Are there any classes in your vicinity? (Cause other competitors will be getting lessons too)

I would use the highest amps practicable, without burning a hole in the material. 3.2 rods, you could use anything between 90 amps for light stuff ( exhaust pipe etc. ) up to 160 amps on heavier steel.

pedigree 6

The thicker the steel the higher the amps and the thicker the welding rods.
Sorry if that's not technical enough. I'll have to look up the chart on the welder. A hand as steady as a surgeon helps as well. Practice makes perfect and a good teacher helps as well.

_Brian

Clean steel and dry rods is a huge huge part of clean welding.
Otherwise you have steam and crap disrupting the weld pool.

RobinBanks

And using an invertor welder makes it easier again. I'm self thought but sometimes my welds can be terrible. Some tips i picked up.

• Clean metal before welding, remove rust galvanise etc
• Good earth close to the weld
• Adjust amps to suit thickness of steel but somewhere between 100-140 seems to work on most steel
• Watch the pool, not the steel if that makes sense. Speed up/slow down based on pool formation and evenness
• Keep rod very close to the joint, when rods strikes begin to lift away from steel. If you move to far the weld will begin to splatter. You will see dots around the weld after it cools.
• Try to use an invertor welder if possible. Its easier to weld with an invertor welder but not necessarily any better. I have a normal arc welder but have used the invertor aswell.
• When welding vertically turn the amps right down to prevent droplets. I prefer to weld from top to bottom holding the pool in place until it starts to solidify.
• Where there is big gaps to fill, push the pool into the gap, move out allow to cool slightly and repeat until gap is closed.

Hope this helps!

blue5000

Only thing to add is move the rod in very small anti-clockwise circles.

dzer2

Oh where to start.

You will know when you have the right amps when your weld runs in a pool around 12mm in dia when you chip the weld make sure there is no under cut on the original metal you have 10 amps tp play with.

Its a bit like anything if you want a top job pay a little more and buy good rods and welder.

patsy_mccabe

To add a few;

• Prepare the metal well. Bring it up to a shine. Grind in chamfers or angles at the edges.
• Keep the rods in the hot press. They stay dry there.
• Clean the metal to a shine too under the earth clamp. Add a clamp over the earth connection.A good earth is everything.
• Get an auto dimmer helmet.
• Unwind extension leads fully. They'll heat otherwise.
• Try and not breath in the fumes.
• Try and weld horizontal if possible. A lot easier than vertical.
• The heat of the weld will be generated out directly from the rod tip, so when welding light to heavy metal, slant it more to the heavy side.
• Practice, practice, practice,.....

Nekarsulm

One sign of a good weld, the stag will rise up off the weld in a continuous piece, in a gentle curl.

mickdw

I'm an much a beginner as anyone can be so this is probably a silly question but how do you know how fast to go along the joint?
All I know is once I start welding, the rod goes pretty quick - feels like melding a chocolate rod onto a hot surface. I tend to panic alittle and start moving too fast I'm sure.
Any guideline on how fast one should move?

Zr105

mickdw wrote: »

I'm an much a beginner as anyone can be so this is probably a silly question but how do you know how fast to go along the joint?
All I know is once I start welding, the rod goes pretty quick - feels like melding a chocolate rod onto a hot surface. I tend to panic alittle and start moving too fast I'm sure.
Any guideline on how fast one should move?

That all depends on what your welding and amps your using really. It's definitely not something to rush, don't worry about burning through rods quickly, if your moving to quick across the joint you won't be welding it together at all, just putting a bit of a bead along the top rather than actually getting any burn in.

When your getting a good weld and good enough penetration you should be able to see discolouration on the back of the steel inline with the weld, I've no pics handy of it unfortunately but you can see on this pic the way the colouring is going the full depth through the steel,

Most of the big points are covered above really, clean steel, dry rods etc, try to have a small gap between things to burn into, ideally if welding heavier plate you should really chamfer the plate down.

Take your time and do like a row of small joined up e's, or in other words come out of the weld forward then back in then out again in small circles


As for rough guide on amps I normally end up round 100 amps for 3-6mm steel, then up 120-140amps+ for heavier plate(10-12mm) and really would want to be higher again on heavier plate.

kelslat

After doing pipe welding for a few years and seen different methods used by different welders like circular weave, zig zag weave, trianglar weave up side down T weave, etc.. there are alot of methods to weld. Get someone good to show you and when you know how the weld should look keep practicing yourself. The more you practice the better you will get. I have also seen some fabricators gifted with a mig welder but very poor with a stick welder.

kowtow

Greengrass1 wrote: »

How does one do a very clean weld ?

For a very clean weld I think you need what's known as a "welding curtain".

It's a heavy fireproof fabric device and you put it up between whatever you are welding and any onlookers before turning the welder to full power.

Then you slip out the back of the curtain and take the item to the local fabricator who will do a neat job, returning to cut the power on the welder and drop the curtain in time for a round of applause.

At least that's what I assume it is for.

visatorro

cut a groove into the pieces you're welding. Kindof a V shape when you put the pieces together. during the welding course they'll tell you to use bottles to further clean the joint. might be abit overkill.
one thing id do is buy a auto shield. about 100 euro. well worth it.
practice is the only way. sounds stupid but if amps are correct ( they've been posted already) then you can't really put on too much weld I think. the slower the better. some good tips here. oh and don't leave any skin exposed, you'll know all about it the next day. buy welding gloves. be very careful chipping the slag because it goes flying, so glasses are should really be worn

jfh

was a welder in a previous life, glad to be rid of it:P
did TIG, MIG & stick, found the TIG the hardest to perfect, but didn't do a whole lot of it, it's really about getting a few sheets of steel & practicing.
practice practice practice, it's very hard to give tips until you actually start at it. of course there's certain thing that help

good rods & keep in hot press
nice clean steel
amps depend on the position that your welding, up , flat, overhead & thickness of metal & rods, you'll know if it's too low as the rod will stick
to create a wider bead, zig zag over & back
slow & steady.

best of luck in the competition

dohc turbo2

jfh wrote: »

was a welder in a previous life, glad to be rid of it:P
did TIG, MIG & stick, found the TIG the hardest to perfect, but didn't do a whole lot of it, it's really about getting a few sheets of steel & practicing.
practice practice practice, it's very hard to give tips until you actually start at it. of course there's certain thing that help

good rods & keep in hot press
nice clean steel
amps depend on the position that your welding, up , flat, overhead & thickness of metal & rods, you'll know if it's too low as the rod will stick
to create a wider bead, zig zag over & back
slow & steady.

best of luck in the competition

Practice with plenty of scrap bits u can pick up. As said above different thickeness metals will need different Amps so ul have to get used to that, stick is simple when u get used to it ,mig is fast and clean once steel is clean , and tig is not for everyone but is lovely when done right , spent 7 years making catering equipment and had to be 100% , ul be grand with a bit of practice

einn32

Only ever arc welded. I definitely found an inverter welder improved my welding somewhat compared to the transformer type. Some days it is awful looking. I started off just welding straight lines on different type scraps. It definitely is down to practice.