Thread: Welding strength?

Sorry but they are most definitely not good enough for a trailer. When they come apart even at 60 km/hr that trailer will look pretty ordinary poking through the windscreen of an oncoming vehicle and your insurance will not cover you for this eventuallity.

There should be no stopping and starting, no pits or craters containing flux, and no lumps. and for extra strength you should not grind away the weld when you have finished. Leaving the weld to show in its entirety is a critical factor in demonstrating it has been properly joined,

It looks to me like you need to do a lot more practice in getting good clean continuous straight welds on thick flat pieces of steel before even trying to join two pieces of steel.

You need to clean away all the paint and gunk at least a couple of cm either side of the join, turn up the current another 10A more than you have and see how you go. Once you can weld continuously on a flat surface at that current - turn the current down a bit and practice some more and keep doing that until you get close to the right current. Then you can think about making some joins. Get yourself a good book and practice the steps - you can't expect to weld SHS properly straight up. Actually I would really recommend doing an night school class and make a few less critical things before starting with a trailer.

Yea you need to get a bit more practice, don't worry though we all started welding like that and the only ones who say they didn't are liars..

don't worry though we all started welding like that and the only ones who say they didn't are liars..

Yep. I agree.

The welding style you have mastered already is called "bird #### welding" Everyone knows how to do it, and less people know how not to do it.

Good advice from above, but if you can't do a course, look up some of Grahams old posts, which have decent instructions for welding thin walled material with a stick.

well./...when i praticed i managed to get some decent non stop lines, One of the issue i had was try to get the arc to start as it either sticks or produces no spark.
I am using one of them cheap Ozito 130amp Arc welder and most of the time i was going it blink as I could not see a thing...I think the lens were rated 9 or something like that.

I'll grind off most the welds tonight and have another go with a auto helmet this time...the mask that it came with is retarted.'

I've read alot of Graham's post and learnt alot but still struggling with the starts ( ie not sparking up), what do you think that is related to?

The welds seem to be able to hold my weight (70kg) bouncing on it..?
I'll be putting alot more braces in to compensate for the sh!tty welds...


ps i did not grind the paint off as i read somewhere the aarc welder can burn through it?

regards

ncrease the current or use a smaller rod.

Also check that you have a really good earth. Don't expect a good earth if your clamped to painted steel.

When you are using the welder how close to your weld is the Earth clamp.
If you are finding it hard to strike an Arc there is the chance that you have a bad Earth,remove the Paint and clamp in this position.
In your earlier post showing your trial welds did you have a problem strikeing an arc.

Your statement about the welds holding your weight maybe correct but they are not Roadworthy or acceptable for use on a Trailer.
Not 100% sure of this but rule of thumb 1" of weld should hold a ton a far bit more than your 70Kgs
Dont try putting extra braces in to compensate for the welds,if your going to register it(or if they pass it) you will reduce your load carrying capacity due to the extra weight of the trailer.

Back to your welding get some scrap RHS and practice on that ,increase your amps to max and see how that goes,if it burns through reduce the amps a little.
The reccomended amps for the rods you are using may well be correct but maybe your welder is not putting out what it says.
No real need to remove the paint before welding except for your earth clamp and keep that within 300mm of your weld or as close as you can.

Ohh...I think you are correct about the earth as I've clamped too far apart ( on the other end of a 5 foot RHS). In the welds in the picture I did have problems striking arc sometimes when the rod touches the metal it does not even spark.

I am using 2.5mm rods on 3mm RHS, The welder I have do not have ampage settings rathe just a crude sliding thing according to the width of the rod i am using...I'll try and crank it up a little more.

What do i need to look out for to ensure that i have good weld both penetration and fusion? Any telltale singns? I was actually expecting bit of the metal to fuse together by each piece melting alittle?

Can someone please post pictures of what a good arc weld looks like? In detail?

thanks

What part of Sydney are you in.

I'm near the airport ( 5 mins drive), are you also in Sydney?

Yes St Marys area,if you have no luck might be able to arrange a bit of practice.

Pipeclay,

Appreciate your offer mate, if i get stuck i'll give you a bell.

The thing about welding is that it is hard. My advice is to start your journey of learning by concentrating on making each weld as good as possible no matter how long it takes. Follow this procedure:

Clean that paint off; it'll make better contact.
Set up the joints with a slight (2mm) gap between them (this will fill with weld)
Sit down next to the parts to be welded
Get comfortable
Set up the angle of the electrode in the holder so it's right for you
Make sure your helmet is comfortable and neither reducing your IQ (tight) nor threatening to fall off (loose)
Tack each corner
Get close to the weld as you start so that you can see what is going on
If you start blowing holes in it stop and reduce the amps (gradually)
If you start dropping bird p**s (see your photos above) increase the amps a bit (gradually)
Don't be afraid to clean up your welds with a grinder and wire brush and go straight back over them.
Read what Grahame Collins has written here, then go through this list again.