Another first attempt, not as good as it could be..

[thoward]

Hello all

I am a first-time welder. I am a theatre technician and we set-build - most traditional theatre sets are made with 3x1 and ply, with hinges and screws, but more and more are being made out of steel box and rectangle - so in order to keep up with the times I fine myself needing to be able to weld.

I have bought a Clarke 135TE as my budget wouldn't stretch much further, and I had a first attempt using some 2.5mm Unistrut that I had in the shed. Cut some right angles and had a go but I think I need some improvement...



If I've got it right then I've not really penetrated enough. I did grind these away and the join was smooth at the top but when I tested (I was able to smash it apart with a hammer) looked like had barely penetrated.

I was on setting 3/4 on the Clarke as I didn't think I needed to get up to full power but I think more power and a little more concentration might have been in order.

This is only my thoughts though and any feedback appreciated

 

[thoward]

Forgot to mention - this stuff is Galv - I went over it with a wire brush but whether I took everything off I don't know. Would being galv make the penetration harder?

 

[rtbcomp]

Welcome to the forum.

Galvanising will contaminate the weld, get back to clean shiny steel.

Galv must be removed with something more aggresive than a wire brush, a grinding disc or flapdisk would be better. Make sure you are protected from the zinc dust in the air when you grind, and weld in a well ventilated place.

 

[Robotstar5]

Grind the galv off first, practice straight runs on the flat before attempting joints. The tutorials on here are very good, have a look at them.

....and welcome to the forum.

 

[BrokenBiker]

if you can get hold of a few pieces of scrap 4-5mm off cuts of steel you can practice straight beads on them first. you will struggle with butt joints and fillets until you can run a decent bead on a plate.

galv is dangerous stuff, needs to be ground off or avoided all together, and even after grinding it off I make certain I have a decent 3M mask on

 

[thoward]

Thanks guys, I'll leave the galv alone then.

I did have a look around but the only sheet I could find was really thin (~0.5mm) so I was just blowing holes in it. It was also rusty as sin.

I will head over to b&q in the morning see if I can pick a couple of bits up to practice on.

 

[BrokenBiker]

do they sell steel in b and q? ive never noticed it the 2 local to me

 

[Richard07]

Try wickes, not ideal for practice but its alot cheaper than b an q. They do meter length flatbar for around a fiver, 2mmx40mm i think, i got some not long ago for a garrage door fix.

 

[thoward]

Thanks,
I picked up a 2mm flat, 4mm flat and some 2mm 25x25 from Wickes. Was intending to practice on the 2mm and then maybe make something out of the 25mm box, but I didn't get that far. First project I am hoping to make is a ladder rack as I need something to store two extension ladders on the shed wall, and ladder hooks aren't quite deep enough.

I had a look at the tutorials and had a go on some 2mm, and I think my penetration is still rubbish

So I can do wide with what looks like not enough penetration to me.


Narrower


This point I wondered if my welder wasn't man enough to blow through, so I did burn through to see if it was possible, I had to pool up a lump for about 5-10 seconds and it fell through


So I have a couple of questions - what do I need to do to improve penetration? Should it be more power, more wire feed, slower movement, or a bit of all three?

When I was welding these, by the time I'd finished that whole section of 20mmx2mm bar was glowing orange. Would you expect that from this? Is that just how it is for something so thin & narrow or am I overdoing something?

Most of these were on the middle two power settings (I think the welder is 35amps-135amps) with a wire speed of about 6/10.

Thanks for all your help, fortunately I'm not looking to do any kind of structural welding, I'd just like to be able to do 25mm box section for theatre sets

 

[Jan]

You don't mention whether you're welding gas/gasless (flux cored). I would say that you need to pay a little more attention to the wire speed. Even a slight difference either way - up or down - can make quite a difference to the smoothness and penetration of the weld. Travel speed is just something that will come to you if you practice enough.
Getting the bar glowing from a series of rapid welds is pretty normal as it soaks up heat a lot faster than it loses it.

 

[thoward]

Hi mate it's gas. I've got a Clarke 135te using 0.6mm solid wire and those disposable co2 bottles. I'm hoping I can just stick with those small bottles as although I might get through a few of them I'm not planning to do any serious durations of welding so should be easier.

 

[BrokenBiker]

if you want more penetration at the top end of your welder get some 0.8 wire.

 

[Jan]

Forget any type of disposable gas cylinder. The quantity in even the CO2 ones is miserable. If you must stick to CO2 then get the correct regulator and flow gauge and source the much larger (and far better value) pub gas bottle. Watch out for the actual contents as some of them include nitrogen which is definitely not what you want in a shielding gas! Be aware that a cylinder contents/pressure gauge is not needed as the gas pressure inside a full cylinder is under 10BAR right up until a minute or two before it completely runs out.

 

[BrokenBiker]

if you want to stick with disposables that is fine, nothing wrong with the gas quality just a bit low on content. the first bottle of rent free co2 is going to be around 70-80 quid and if you can manage to find a pub cylinder you still need to find someone to fill it without a contract. fire extinguisher places might, but not always as its not their bottle, and breweries might, but most will want a contract, and pub suppliers will insist on you returning your bottle and them giving you a full one, which then means you need to have one of their bottles to begin with.

if you are just having a play and maybe wanting to do some quick repairs on a frame or a quick 5 min job to make a tool or extend something then the disposable bottles are ok. also co2 paintball bottles will work with the right regulator, jody on weldingtipsandtricks has a video where he uses one

 

[thoward]

Thanks guys

I might get a proper bottle attached in the long run but at the moment I've just got the disposables. Is there anything in the argon/co2 mix or am I better with straight co2?

Re the wire, is there a big difference between 0.6 and 0.8 or I am better jumping straight up to 1mm?

 

[Bill Edwards]

You certainly don't want 1mm wire, I don't think your machine would even be able to accept it. Unless you're welding very thin stuff (under say 1.5m) often I'd go for 0.8mm, but I don't think it is that important.

Argon and CO2 is much nicer to weld with than CO2, though CO2 does allow you to stick metal together.
A great deal on gas is the 'Volkzone' offer from BOC, where you get a big (just above waist height) bottle of 95% argon, 5% CO2 (the perfect mixture for the sort of work your welder is designed for). You rent the bottle, the costs are around £37 + VAT per year, refills cost £25 + VAT. The bottle holds a vast amount more than the disposables, the difference is silly.

 

[thoward]

Think it will run 1mm wire as there are three electrode ends in the box, .6, .8 and 1, but the wire feed only has two groove sizes.. I will pick up some 0.8 instead though.

I'll see how quickly I go through the disposable bottles as we can get those on account and I'll not be footing the difference- if we are burning money on them though I'll look at the bigger options

 

[thoward]

I've been having a bit more of a go and having a crack at my first project.. And I've got some pictures

So far I've found CO2/Argon mix I be nicer than CO2 so I've switched to that. I've been through one of the little disposable bottles already, but at the moment I'm making up 8ft square frames so need to be able to move the welder about, so I'll probably get a boc bottle but sticking with disposables for now.

I've got an 8ft square frame, which is to make part of a theatre set, it'll be bolted to the back of a piece of staging (steel/Ali box with ply top) and sheeted with quarter inch ply to make a wall

 

[thoward]

 

[thoward]

I know these welds certainly aren't great, which is why I put the triangles in the corners, so id really appreciate some pointers as to how to do better