7 replies to this topic

[TheMiniDream]

Hi, I'm looking at learning to teach myself to weld and think I've ground a pretty cheap one. It's £65 second hand and comes with the mask.

Is this welder any good for learning on? Thanks

[tractor]

Mig is the best type of welder to use when working on car sheet metal and I think the 145 refers to the amount of amps it can produce. You generally want about 130A to comfortably work on car sheet metal

The amps are quite important as if the welder can't produce a hot enough weld the two pieces of metal won't fuse properly and you'll just produce a weak joint

So yes sounds alright to me and £65 is very reasonable, assuming it works ect


Trac

Edited by tractor, 28 April 2013 - 07:05 AM.

[Willthewelder]

You will be at around 60a on most things on a mini aside from inner wings and flitch panels. The bigger your welder's capacity the longer it can weld for at a given amperage. It would have a 100% duty cycle at about 60.

[Elliskwleisk]

You will be at around 60a on most things on a mini aside from inner wings and flitch panels. The bigger your welder's capacity the longer it can weld for at a given amperage. It would have a 100% duty cycle at about 60.

What does the percentage duty cycle actually mean?

[sonikk4]

It's the welders ability to function without overheating. If the welder is fan cooled their duty cycle will be better but remember if you weld at max power then the duty cycle will be shorter.

[Willthewelder]

Say your welder was 100A and it has a duty cycle of 50% at 50A  which means it can weld for 5 in every ten minutes without overheating. You can calculate it retrospectively by changing the power setting used and the time. There should be a plate on your welder somewhere.

[ibrooks]

Beware - Screwfix (and no doubt others) were selling a bunch of cheap MIG welders before Christmas that didn't have a low enough setting to weld car bodywork thickness metal. A good few people bought them just thinking bigger is better and then realised that they were no good for what they actually wanted to do with them - they are now finding their way onto the second hand market cheap. Can't remember what the make is but I think they had red cases.

 

As has been said you don't need anything like 145 Amps for car bodywork stuff but generally a bigger machine will be able to do the smaller stuff without breaking a sweat. Duty cycle has been explained but it can be a bit mis-leading when looked at in such simplistic terms. When you are welding you rarely have the trigger pressed all the time. You weld a bit, you stop and look at it to check it's OK, you weld a bit more somewhere else on the patch, you stop to check again and maybe belt it with a hammer if it's distorting through the heat or you move a clamp, then you weld a bit more, then you stop whilst you move to a more comfortable position, etc. In practice my Clarke 150 can "weld" all day and has an effective real world duty cycle of 100% for my use.

 

Iain

[lrostoke]

Personal preference but I'd also check if its gas or no-gas...I prefer gas