Three options at the same current level
A fabrication shop welding sections and plate from 3 to 20 mm needs a 400 A MIG/MAG machine with a separate feeder and water cooling. At that level the choice comes down to three options. Each has a different price on the invoice and, more importantly, a different bill after three years.
The figures in the table are indicative and given net, for a set with a feeder, an interconnecting lead 3 to 5 m long, a torch and an earth lead. A specific offer can differ by somewhere over ten percent either way.
| 400 A option | Indicative net price | Duty cycle at 400 A | Care after the sale | Parts after 8 years |
|---|---|---|---|---|
| Used premium (Migatronic, Fronius, GYS, Kemppi) | 22 000 to 28 000 zloty | 60 to 100 percent | first year of the service package in the price | available, authorised service |
| New, Spartus or Magnum class | 12 000 to 18 000 zloty | 35 to 60 percent | 24 months from the maker | cheap, but dependent on the importer |
| New premium | 45 000 to 70 000 zloty | 60 to 100 percent | 24 to 36 months from the maker | fully available, service records |
Duty cycle: the first figure you check
The duty cycle is quoted over a 10 minute period at an ambient temperature of 40 degrees Celsius, in line with EN 60974-1. 60 percent at 400 A means 6 minutes of arc and 4 minutes of cooling. If a machine gives 400 A only at 35 percent, you get 3.5 minutes of arc in every 10.
How many metres of weld is that
A fillet weld with a 5 mm throat over a length of 1 m is roughly 2 to 3 minutes of pure arc time at a current of 280 to 320 A. A machine with a 60 percent duty cycle will make that weld without stopping and start the next one. A machine at 35 percent will stop halfway through the second metre and sit there cooling.
With one welder to one machine the difference shows up in metres per shift, not in a table. On heavy parts and long runs the duty cycle stops being a figure on a data sheet and becomes your production schedule.
Where cheaper machines lose current
The current on the rating plate is often measured at a 400 V supply and 20 degrees. At 380 V, with a long extension lead and 30 degrees in the shop, the machine drops lower. Check whether the maker quotes three duty cycle points, at 40, 60 and 100 percent, because a single figure says very little.
The second thing is the feeder. Four drive rollers and a metal housing keep 1.2 mm wire running true on a long lead. Two plastic rollers start to slip after a few hours on hard cored wire.
The cost of downtime, the largest item on the bill
The workshop rate in Poland is roughly 120 to 200 zloty net per hour of station time. One day of a machine standing idle therefore costs 960 to 1 600 zloty, before you add the delay to the job and the shuffling of people. With two stations and one welder, one machine down eats half your capacity.
What counts, then, is not so much the failure rate as the time to clear the fault. A machine whose service centre has the part on the shelf and arrives within 48 hours is cheaper than a machine that has to go to the importer for three weeks. The same mechanism is at work in our service package, where we provide a replacement machine for the duration of a repair.
Parts, consumables and what you use up every month
The torch, contact tips, nozzles, liner and rollers are a cost independent of whether the machine is new. A shop welding on one shift spends roughly 150 to 400 zloty net a month on them. That item looks the same in all three options.
The difference starts with machine parts. In premium machines the power module, the control board and the cooler pump stay in the catalogue for 10 to 15 years after production ends. In cheaper designs, parts availability depends on whether the importer is still working with the factory. Check that before you buy, not after a breakdown.
Ask directly for three part numbers: the power module, the control board and the feed motor. If the seller gives them from memory and tells you how many are in the country, you have your answer. If the answer is that one can be ordered if need be, add two weeks of downtime to the bill.
Who is responsible for the machine after the sale
A new machine has a manufacturer warranty, usually 24 months, sometimes 36 after registration. With a used machine there is no commercial warranty, but the price includes the first year of the basic service package. You buy further years separately, and then repairs come out cheaper, a periodic inspection is added along with priority in the queue. The practical difference is that with a used machine you are dealing with the service centre that stripped it down before the sale.
Every unit is checked in our own service centre to current standards and given a condition of A, B or C. Condition A means full working order and cosmetics beyond reproach, condition B full working order with signs of use, condition C working order with visible wear to the casing or a missing item from the set. In the product listing we describe the load test, the state of the feeder, the cooler and the interconnecting lead, and what has been replaced. You get an inspection report with the extended service package. We describe the method in detail in the service section.
A worked example over three years
Below is the same workshop, three machines, a horizon of 36 months. The assumptions: a downtime rate of 1 200 zloty a day, one inspection a year, resale value estimated conservatively. This is an example, not an offer, but the proportions hold in most cases.
| Item, 36 months | Used premium | New Spartus or Magnum | New premium |
|---|---|---|---|
| Purchase, net | 25 000 zloty | 15 000 zloty | 55 000 zloty |
| Inspections, 3 x | 1 800 zloty | 1 200 zloty | 1 800 zloty |
| Repairs outside the package | 2 000 zloty | 3 000 zloty | 0 zloty |
| Downtime, days x 1 200 zloty | 2 days, 2 400 zloty | 5 days, 6 000 zloty | 1 day, 1 200 zloty |
| Value after 3 years | 15 000 zloty | 4 000 zloty | 32 000 zloty |
| Net cost over 3 years | 16 200 zloty | 21 200 zloty | 26 000 zloty |
The cheapest machine to buy comes out the most expensive over three years. Two items do that: downtime and loss of value. A cheap machine after three years of hard work is worth a fraction of its purchase price, because a second hand buyer is not counting on another five years of service.
Change one assumption and the result shifts. If the shop works 2 hours a day instead of 6, downtime falls to one day in every option, and the difference between the columns comes to roughly the difference in purchase price. That is precisely the point at which buying cheaper pays.
When used premium wins
A used premium machine makes sense when you weld several hours every day and need more than 300 A. Electronics in that class were designed for 10 000 hours and more, so a machine after eight years of single shift work has as much again ahead of it. On top of that comes the support of a service centre that knows the circuit diagram and has access to parts.
The second case is welding aluminium and thin stainless steel, where the fineness of adjustment and the library of synergic programs are what count. The difference between a premium machine and a budget one shows on the weld face from the first metre. Pulse and double pulse in cheaper machines are sometimes reduced to a single slider, which on 1.5 mm sheet ends in a burn through or a cold lap.
The third case is a workshop that already has one machine of that make. Shared torches, rollers, cables and the same interface shorten changeover time and simplify the parts store. The welder does not learn a second control panel, which has real value when people change.
When a cheaper new machine is the better choice
A new machine of the Spartus, Magnum or Ideal class makes sense for occasional work, up to 2 hours of arc a day, and at currents up to 250 A. Then the duty cycle is not the bottleneck, and 24 months of manufacturer warranty plus low prices for spare parts are worth more than a reserve of power.
The second situation is a standby station or work away from base, where the machine rides in a van, stands in the dust and gets knocked about. There is no sense in exposing a 50 000 zloty machine to that. Have a look at what we have in the new MIG/MAG category.
The third situation is a workshop that is just starting and does not yet know its own workload. A cheaper machine for the first year is a sensible way of finding out. The alternative is rental for a few months, because then you pay for what you actually use and you do not tie up cash.
Four questions before you decide
- How many arc hours a day do you plan and at what current: that gives you the duty cycle you need.
- What does a day of the station standing idle cost: multiply the hourly rate by 8.
- Who will repair the machine within 48 hours and whether they hold the part.
- What comes in the set: feeder, torch, earth lead, cooler, trolley, interconnecting lead and its length.
The answers to those four questions settle the choice faster than comparing data sheets. If you have an old machine to hand over, we will value it as part exchange and deduct it from the new purchase.
Let us do the sums on your figures
Give us your arc hours, your material thicknesses and your station rate, and we will prepare a comparison of two or three specific machines from stock, together with the three year cost. Call us, or go straight to the used MIG/MAG category, where every machine shows condition A, B or C and a list of what is included.