Hi I have been thinking of getting a mig that will do land rover repairs and various projects using up to 4mm steel. I was thinking of getting a jasic inverter but have decided to go down the transformer route. I am looking at the oxford 200-1 mig maker. Can anyone advise me if a duty cycle of 135 amps at 35% will be ok for a hobby user. Many thanks, mike
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Bill Edwards
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You tend to find that in normal use that kind of duty cycle isn't a problem as you normally spend most of the time measuring, cutting and cleaning to do a bit of weld, then you scratch your head, measure, cut and clean again before doing any more. Unless you've a lot of long runs of welding to do in one go it's normally no problem.
Most LR repairs (chassis, bulkhead etc) don't require anywhere near full power and will certainly never test the duty cycle.
Most LR repairs (chassis, bulkhead etc) don't require anywhere near full power and will certainly never test the duty cycle.
chevy2
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For most of the members on here duty cycles on machines are not an issue for most to worry about,
its only an issue for those that work in the industry that are maybe welding up stuff like batches of 50 or 100 brackets on a continuous basis,
i own a pretty much top of the range machine but it only has a 20% duty cycle at its 200amp max output,
I rarely use the full 200amp output and if i do its only for very short periods, most of my stuff is under 150amps where the duty cycle is nearer 60% so its not gonna slow most production or overheat the machine,
rule of thumb is buy a machine with a max amp of what you'll occaisionally only use, that way duty cycle is not a real problem,
lots of machines will tell you when you're close to the duty cycle...when the torch gets too hot to hold!
its only an issue for those that work in the industry that are maybe welding up stuff like batches of 50 or 100 brackets on a continuous basis,
i own a pretty much top of the range machine but it only has a 20% duty cycle at its 200amp max output,
I rarely use the full 200amp output and if i do its only for very short periods, most of my stuff is under 150amps where the duty cycle is nearer 60% so its not gonna slow most production or overheat the machine,
rule of thumb is buy a machine with a max amp of what you'll occaisionally only use, that way duty cycle is not a real problem,
lots of machines will tell you when you're close to the duty cycle...when the torch gets too hot to hold!
Rig Pig
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I have to disagree, I'm beginning to get fed up with the duty cycle on my mig. I make up the parts as I go, tacking everything together then fully welding it up - until the performance of my welder drops off & I have to stop and let it cool down, very annoying !
Can you tell us the model your using?
chevy2
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Thats the welders way of telling you to get a higher amperage machine so that you're not dropping into the duty cycle area too often,
Welders are good at doing that!
Rig Pig
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Yes it's time to upgrade - I fancy a big old 3ph when one turns up at the right price not too far away, my current mig is a Snapon 130 - it's brilliant for bodywork, but not for running flatout on heavy steel. I suppose I shouldn't be lazy and go and get the old Oxford out, it eats rods all day and hardly gets warm.
Wedg1e
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Hey Pig, I have a mate's SnapOff 150 in the workshop (I sort of promised I'd do a Eurotorch conversion for him... about 5 years ago 
) and the duty cycle on that isn't great either.
My Oxford 120s has had the puddings pulled out of it over the years and it never trips on thermal so they were doing something right... and if I need proper poke I get the Oxford 300 out: that can deliver 225A at 100%
(although I have to take it into work to get a big enough mains supply, it needs 60A flat-out).
) and the duty cycle on that isn't great either.My Oxford 120s has had the puddings pulled out of it over the years and it never trips on thermal so they were doing something right... and if I need proper poke I get the Oxford 300 out: that can deliver 225A at 100%
(although I have to take it into work to get a big enough mains supply, it needs 60A flat-out).
Wallace
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My first Mig in the mid 80's was a Cebora 120 which was fine for welding cars and light fabrication then my Father and I landed a job assembling storage cages for a warehouse. The limiting factor to how many we could make in an hour was the machine duty cycle, best we did was 3 with the Cebora and 5 with a bigger Einhell Mig. Using both machines to share the load we made 7 per hour but that was still limited by their duty cycles.
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For production welding at around 120A we normally specified 350A machines so no problems with duty cycle.
normspanners
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My big old 3ph lincoln was at least 500amps continuous and i know that for a fact using 1.6 wire flat out on the wire speed and using 6mm bright steel rods as a filler al la tig for 40 hrs non stop 
on some 25 and30mm fillets in and out, 5ft square stepped ally ingots moulds , most run were 5ft long in a continuous run,I used 12rolls of wire in two days, all so that I could go on holiday with the family, then spent the next two days with a
migrain in adark room 
HA.I had two pair of gloves with metal tape on them to change when they got too hot and also it melted the plastic lens in my head shield.
That old girl just kept on and on and on. I also could weld car body work on 1mm wire it was so good. I miss that
welder.
chevy2
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The discovery channel are after you,
I had two pair of gloves with metal tape on them to change when they got too hot and also it melted the plastic lens in my head shield.
That old girl just kept on and on and on. I also could weld car body work on 1mm wire it was so good. I miss that
they wanna do a show called extreme welding
normspanners
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I designed them, they were similar to this shape but with square corners 5x 5ft square with3x3 base all sloping walls 10 degs no under cuts in the inside welds but i put a 8" hollow cone in the centre . The problem with the moulds (or sows) as in the picture was, that because the centre was the last to cool, it would create a large dip in the centre that filled with water the last thing you want when dropping them into a large 800 deg furnace but with a hole through the centre there was no water and quicker cooling and melting
30mm/or 40mm base with 25mm wall thickness and after a few mths of continues casting they would bend like bananas. I think they held 2000kg of molten ally
30mm/or 40mm base with 25mm wall thickness and after a few mths of continues casting they would bend like bananas. I think they held 2000kg of molten ally
