32 replies to this topic

[GreGGers]

okay so i got a new mig welder and have a bit of experience with stick welding but when i come to weld a bit of old panel i just constantly blow holes through:







this is probably the best weld:



these are the settings i'm using with 0.8mm wire and CO2 gas:



could do with some advice

thanks
jack

[speediestevie]

when welding thin sheet if your blowing holes i find it easier to weld in very short bursts then let the steel cool before starting again. i also found that 0.6mm wire is easier when welding thin metal. Have a look on the link below at the video it shows you what i mean
http://www.mig-weldi.../thin-metal.htm

[rickjames]

try turning the wire speed up a bit, try move a little faster,
looks like you are getting penertration,but just a little too much
keep it up!!

[andymini12]

Like said do shorter runs, also you will find it easier if you get some 0.6mm wire.

[tiger99]

CO2 is not good for thin sheet, you really need to be using Argoshield light or similar, which is around 95% argon, 5% CO2. It really does make a vast difference. And, the previous advice from several others is also good.

I am told that very skilled welders (not me!) move so fast that they don't blow holes, and some have the power and wire feed cranked well up, way beyond what I use. I guess that comes with a lot of practice, but if you look at some of the build threads, you will see various people's welding improving throughout their restoration. Your's will too. I find that after being away from welding for too long, it takes a while to get up to a decent standard, so I start with some trial runs, and they don't necessarily come out any better than yours at first. Don't be discouraged, you will get there!

[GreGGers]

thanks for all the replys much appricated i have some 0.6 wire i will give it a go tomorrow

thanks

jack

[sonikk4]

Do increase your wire speed and take it up to six. You can use CO2 for thin metal it takes practise but it will work however overall the C02 Argon mix will be better. Do one inch seam welds. Try and support you arm if you are attempting to weld one handed or if not use both hands.

It is just a case of practising i'm afraid. If you do get a nice continuous weld have a look underneath to see what penetration you have got. If it is not showing good signs then up your power to two and increase your wire speed slightly if you start blowing holes.

[olds_kool_lews]

also, are you using a hand held mask? or an auto darkening helmet? i found this also has a massive difference in the quality of the weld, as you can actually see what your doing as your doing it, instead of faffing about trying to hold your mask and weld etc

[GreGGers]

thanks again very helpful and i'm using a auto darkening mask

jack

[PaulColeman]

If you do accidentally blow holes in the panel stick a plate of copper behind the hole and you can fill it in with weld because the weld won't stick to the copper I've done it lots of times!!

Paul.

Edited by PaulColeman, 16 January 2012 - 01:48 PM.

[SAL 821X]

If you do accidentally blow holes in the panel stick a plate of copper behind the hole and you can fill it in with weld because the weld won't stick to the copper I've done it lots of times!!

Paul.

Great tip thanks for that Paul.

Good luck OP in about to start welding on my van for the first time lucky its only the floor though.

[GreGGers]

great tip thanks.

haha i have a bit more than the floor

jack

[Frog]

You couldd try doing several small tacks, a bit like spot welding rather than trying to continuos seam weld, this reduces the heat & limits distortion on the panels.

[GreGGers]

okay so had ago tonight and here the results:

this is with 0.8m wire and i turned the wire speed up to 6:




then i tried with 0.6m :/..




i think i'll stay with 0.8m. :)

thanks

jack

[SAL 821X]

Much better Jack, now its time to get get cracking fella.

:)