Hi everyone, ive read alot of past posts and ive gathered the higher the ampage the better.

But at work theres a Sip cosmo gas100 in the shed doing nothing. so my question is will i get away with constructing a haynes roadster with this welding set.

Ive also gathered Sip cosmo's dont have the best rep

Thanks in advance Will

90AMP WILL be a bit short...
think its max 2.5mm electrode.
for tig it well be enough.

saying that on ebay you can buy for 120pounds 160amp TIG.

Tks

R U ON ABOUT A MIG???

http://www.mig-welding.co.uk/buying.htm

what are you doing? welding 1.6mm box on 90 amp mig (ie full power) will be fine. welding thicker stuff like wishbones etc .......

well, i know people who's done it, they're engineers and did it very carefully. Personally i'd want a more powerful welder (but i'm not as careful as the bloke i'm thinking of)

i did a lot of my chassis with 90amp mig, did tests and the penetration was fine (and in a couple of places i burnt through by accident). I've now upgraded to a 150amp mig.

I have a 90A welder and am welding a chassis at the moment. I'm not on full power and find that I'm on the edge of blowing holes in the cut ends of the tubes. I do plan to weld in the 3mm plate from both sides.

Edit to say mine is a 100A welder.

[Edited on 18-1-2008 by smart51]

The only thing with smaller welders is their duty cycles.
You may find that it cuts out from time to time on thermal and you will have to wait a while for it to cool down and reset.
It will be fine for a 7 chassis.

I would say not the best welder.
The motor is not powerful enough, is struggles resulting in bad welds.
Got fed up of poor welds, so got a 170 amp one. Much better!

Darren

If your determined to do 3mm welds on a 90amp (and can't weld from both sides) there is a trick you can do.

When you're welding a vertical weld you do a christmas tree pattern - start at the left, move to the right, then move up and to the middle, then move down a little and to the left, then to the right, then up and to the middle above the previous middle bit ......

Do the same approach on the 3mm - although offset the weld a little more onto the 3mm otherwise you risk going through the 1.6mm steel. The downside is the amount of heat you'll be putting into the steel (and how long the weld will take - duty cycles etc).

I have a 90 amp mig which I used for my chassis you do have to use it on full power though and I ended up using a stick welder for anything thicker.

i got a clarke 90a welder, i find that i can only use it for a short period of time as when it gets too hot the welds start going funny, it does not have a fan. i am looking to buy a new one soon, something like a 170 or 185.
anyone got any tips on what one to buy? would love a murex but bit out of my budget.

rob

get your self an office fan, take the cover off the welder, point fan at welder.



Honestly it works. I did this for a few years, eventually the welder gave up but i had sterling service out of it. I've seen the same thing used in warehouses with printers who's duty cycle is marginal.