Wayne 4908 not sure of the makeup of the transformer for that machine but have recently rewound one for one of my own machines see pics (6 power settings, 160Amp) Depending on what is usuable from ori transformer will affect price. Wire + insulation sleeving + insulating sheet + varnish + p&p just over £60. I also decided to makeup a new former (ori cardboard one was a bit cooked. Made from tufnol aprox £10 with p&p. Treated it as a learning experance as I had not rewound a transformer before.
Note If you rewind one you can custom the rewind with extra tappings.
Might be worth looking for a similar power rating machine with a fault (but NOT transformer!!) and using the tran from that.
If you do get it rebuilt would be intresting to know what they charge, as from price of parts above plus labour £££?
Hi mike they have 4 sections to the transformer[dont no why].Most pics ive seen looks like the one in ur pics.Dont no if u can see on pics but the back right and the front left are burnt.How hard was it to do rewind ur self?Seen a esab smasheld weld 180 on ebay last week for 60 but it was 3 phase[looks the same welder with esab name]wondering if one from a 3 phase can be used in a single phase?Thanks
Wayne it's not dead easy but is possible! On yours the thinner wire windings that are fried (rear right and frount left) are the primary (240v) part. The mains goes via your power selector switch which selects different lengths of the windings. they have split the transformer in two to compact/make best use of metal core? hink ist is unlikley that you would be able to use one from a three phase machine as it will probbley have a very different makeup of transformer. If you decide to look at doing a rewind then take lots of pics of how things are wired and label all the wires that you have to disconnect to remove transformer. You might as well remove the transformer anyway as it is stuffed on the primarys. Once the transformer is removed you will need to strip it apart by undoing the bolts that hold the "E's and I's" togeather and unstacking it (small wallpaper/paint scraper will help to seperate them. Stack them to oneside for refitting. then you will be left with two square tubes made of an impregnated cardboard. You will need to mount this on a spindle of some sort and have a spool/reel to wind the burned windings of to. As you unwind the burned winding, you need to count the number of turnes (and write it down!!) This will allow you to rebuild it to the same number of windings. As it unwinds you will come across the taps which go to your power selector switch. Make a note at what point these are. You may also found burried in the coil a thermal cutout device (makes you wounder if they ever work!!) Ori on mine was still good!!! have now fitted two. Make a note at what level it is. On mine the winding wire changed size part way through (for the higher power settings) it went from 1mm to 1.5mm. If yours does you will need to note this as well. Yours is easer than mine as on yours the primary (thin wire) is alongside the secondary (thick wire) where as mine had the secondary wound over the top of the primary so had cooked the insulation on that a bit so had to rewrap that rarther than replace.
Does the attached pic make any sense to you?
Wayne It is possible that the reason for the fry was the diodes? You could test that they are working if you can get hold of a low power, low voltage transformer. Then disconnect the thick wires on the two crimped connectors and connect as per sketch then meter output of diode pack looking for DC voltage. Done this on mine as was unsure if diodes were stuffed but ok.
PS take care as mains voltage will be present
Hi to germanscroupe .Was the mig one of these?Is rewinds your friends job?If it is could u get a rough price for a repair just so ive got an idea of price?The smash weld was advertised as 3 phase.Thanks.Hi mike are the diodes[cant see the thread i think thats what u said to test]Anyway the things to test[is i where the wires bolt to the ali plate]Ive removed the transformer?How far would they melt[ if just one layer melted could u not remove that layer? ]What meter setting do u use?Thanks
Wayne, my welder was down on power. Even on highest setting it would not lay a bead on even thin steel. I am not a spark so gave it to my mate who services safety gear for the ship yards up here. He gave it to their tech guys who apparently changed or rewound the transformer f.o.c.
Hi just got an estimate for a repair 600 plus vat.Dont no were they get there prices from.Waiting for a couple of other companies to get back to me with a price.Looks like i be having a go myself
Wayne did not think it would be cheep. Try searching for "motor rewinders" When I was searching I kept coming across a company in Birmingham (west midlands I think). Did not get any quotes as I said I treated as a learning curve ( I work in electro/electronic/mechanical engineering but don't have access to companys that do this kind of work. If you google/ebay "enamel wire" which is what you will need to rewind you will find the main name (with good prices) is a company called "Brocotts". You will need to almost certaintly renew all of the wire on the primarys as the shorting causes an avlance effect ie once it starts to over heat and short some of the winding the current drawn goes up and more shorting and on and on till the fuse pops! If all the wire is same diameter then you can weigh the wire once unwound, less the spool you wound it off onto (you did weigh the spool you were winding it onto first, did't you ) or you could unroll it and measure it either way this will give you a length or weight of wire to order.
This was my order:
• 1 x 1.06mm Enamelled Copper Winding Wire (500g)
• 2 x 1.50mm Enamelled Copper Winding Wire (1kg)
• 1 x Acrylic Coated Woven Glass Sleeving - 4mm x 10m
• 1 x Electrical Insulating Air Drying Varnish - 100ml
• 1 x Nomex Motor & Transformer Insulation 0.36x900x200mm
Hope you are keeping notes on where thoese wires go..
Wayne you might want to look at this thread http://www.mig-welding.co.uk/forum/showthread.php?t=29845&highlight=transformer&page=2 He was rewinding his about the same time as me !! There was something about all that snow and working in a shead (apart from coldddddd...) Note use of gloves to be able to put some tension on wire when rewinding. The machines that do this work are quite impressive.
Hi mike they are the sides with most wires coming out worst luck.What do u do cut the wire after 1st bit and start winding again?I dont understand how u can get 6 or so wires coming out.How long did it take u?
No you will/should find that the wire wrapes around the core, then when a "tap" (read as oen of your power settings) is reached the wire is lead out, a loop formed and then wire goes back to continue winding. The lead out is sleeved with the sleeving! which is usually a glassfibre/non flamable material (that's the acrylic sleeve in my parts list). You have to be caerful while doing the lead out and back that you don't allow the wire already wraped to go loose and unravel (bit like loading a spool of mig wire and leting go of the end....Main thing is when you start winding the new wire on you read your unwinding instructions backwards as you are starting to rewind from the centre outwards (after about 40 to 50 turns I realised I was doing it wrong way...Dooh. Unwind and start again. Gerrr. Keeping count is important but if you should miss a turn or two it's not that critical but best to aim for as close to same number as possible. You need to get the winds snugg up to one another and firmly wraped. So makeup a core (wood block with hole through) to mount the cardboard core onto to stop it getting squshed. You might also find as you are winding that the new spool runs out and you need to attache the nex spool of new wire. If you calculate this correctly you might end a new spool early to attach the next spool when the loop out using first spool then use new spool to take loop back in, this avoids a joint having to be made in the windings.
What length Did ur windings end up?Trouble with me is id loose count as im doing the turns.I can put a spanner down then loose it within space of a minute or two.smoking too much weed in my younger days.Did u see any guides any were before u did urs?Whats ur welder like now as good as before it burnt out?Have u any idea why The transformer burn out[lots of heat].Did u strip urs before u bought the stuff[Getting worrid just thinking of it]
Hi Wayne my windings were a total lenght of wire = 132mts (41 of 1.0mm and 91 of 1.5mm as mine used two sizes of wire for cost?) aprox. This does not inc the aprox 400mm out and 400mm back for each loop/tap. Total number of turns was 430 aprox. Yours will be a bit different due to the way the coils are spread round the iron core, may be less . If you have a sheet of paper to hand when un/rewinding to note down turns then when you get interupted or have to form loop you can jot down number. Main thing is to keep windings nice and tight (if you looked at the link from the other chaps rewind, note the handle length he used!) Use a bundgy strap or similar to keep from unwinding while you go for a pee!! ect cos as soon as you start bet youll need to There are vids on youtube on how to strip a transformer, think most are from geeks wanting to have piles of steel/iron core and copper wire material..... Look for "MANUAL transformer REwinding"
Ref why the trans fried don't know as I bought the welder as "for spares/repaires" thinking it would be a pcb or wiring or motor or anything other than the transformer at fault as I could have fixed thoses a lot easer. I think the reason it fried was that it was being thrashed and the fan is setup to only run when the trigger is pressed so say 2 mins constant weld fan running for that 2 mins, trigger released and now transformer is nice and hot but now fan stops!! and so on. Designed that way but crap ideal. Will fit runon circuit at some point or constant on fan (muffin fans are only about 15 to 25 watt). As I am doing car resto welder is not running flatout at mo.
If you look at first pic this was the fuse used by previous owner.... 6mm steel bolt prob about 300amp blow bit more than 13 amp
Yes I did strip it before ordering because I thought I could rewrap the ori wire with ptfe tape (plumber tape) as it is non flamable and insulated. Madeup a winder to wrap tape around ori wire. Done all that and it nearly worked but only takes a bit to rub off and short to fail so then went with the new wire ect. I did manage to rewrap the secondary (thicker wire) with some better ptfe tape as that would have been expensive to replace ( about 4 or so mm) and yes before any one points it out it is an aluminium secondary. Had to reaneal secondary to soften to allow rewinding but you won't have that problem with seprate secondarys
It goes to show that the thermal cutouts don't always protect the transformer they have been built into - bolted onto. So DON'T relie on just that. Constant fan blowing onto transformer?
Once I get hold of a 10 or more way switch (ori is 6 way) will add the extra loops/taps I made between the lower power settings, equal to power 1 1/2, 2 1/2, ect. May not need but what the hay...
Welder Is up and running and have used ok.
I even drew out the wiring diagram and pcb circuit in my sparetime. Which gives me a better ideal of how migs work in general.
Second pic is of welder before tidying up. When time allows will prob make up some new side panels.
Hi noticed on the top layer of both the burnt ones there is a wire coming out in the middle then it stars again to the end[ not explained well]Ill have to take a pic to explain.It wouldnt have been as bad if the were all seperate than i could have done one at a time.Out of all the places i phoned up and emailed pics for a repair quote only the one replied .The welding supply places just tried to sell me a new machine when i asked them about repairing it.