1987 Sealey Supermig 160 Euro Torch Conversion help please

[rhino666]

Hello, I have finally bitten the bullet and got around to doing this job after around 36 years of owning this welder:-)
I have fitted the Euro adapter, having removed all the included nuts and washers, cut off an inch or so of the brass threaded bar and drilled out the liner holder from 4mm to 5mm for the wider euro metal liner. As you see in the bottom of the first pic, there is a brass piece hanging down, that was threaded on to the old torch, with a heavy duty earth type lead connected that runs to the rectifier under the fan, see the second pic.
Am I right in thinking that this needs to be completely removed?
The original torch had one wire connection, white wire with connector in first photo and I think this needs to be connected to either one of the red or black wires on the Euro adapter?
Where do I connect the other wire please? I am thinking it may go to the same place as where the big old wire mentioned above is connected but hopefully someone can confirm.

Thank you.

 

[chrismac]

I would have a guess, the black wire with the earth type connector is the power to your torch as its a heavy cable, and the small white wire is part of the trigger switch wires, is there not 2 wires, I dont have the knowledge to know the set up if its only one wire for the trigger.

Good luck getting a fuller answer to your questions.

 

[pedrobedro]

Does your original torch operate a solenoid for the gas or just a valve. A friend of mine had to fit a solenoid when he converted an old Mig to euro connector probably where your other wire needs to go.

 

[rhino666]

Thanks for the reply Chris. Your understanding is exactly the same as mine. The single white wire ends up as the second white wire up on the connector to the wire speed and timer PCB; see first photo, lower right. I guess this is the triggering side of power to both torches.
I think the thick black wire is getting current off the rectifier and on the old style torch, that black connects directly up the torch to the tip. The Euro torch does not have any feed directly to the tip, so I am guessing that I simply need to replace the big black wire originally fitted with the second Euro adapter wire?

I have found information available for the Euro Torch Conversion a bit thin on the ground and incomplete, so have added a few more photos to hopefully assist anyone else in my position. The cheap Euro adapter I bought off ebay appears to be of excellent quality, picture two but none of the attached fixings were needed and I had to cut off about an inch off the end of the threaded bar, picture three. The metal liner that has tapered ends was a perfect length; I just had to drill out the welder liner clamp from 4mm to 5mm. I also had to reuse the gas tube, replacing new on the adapter, as crimp fitted at the other end on the solenoid. On this welder I had to fix the front adapter mount sideways as shown to prevent the fixing holes interfering with an inner panel on this welder. I think it worked out quite well - please see pictures four and five. Just need to get the wiring confirmed and ready to test.

 

[chrismac]

Thanks for the reply Chris. Your understanding is exactly the same as mine. The single white wire ends up as the second white wire up on the connector to the wire speed and timer PCB; see first photo, lower right. I guess this is the triggering side of power to both torches.
I think the thick black wire is getting current off the rectifier and on the old style torch, that black connects directly up the torch to the tip. The Euro torch does not have any feed directly to the tip, so I am guessing that I simply need to replace the big black wire originally fitted with the second Euro adapter wire?

I have found information available for the Euro Torch Conversion a bit thin on the ground and incomplete, so have added a few more photos to hopefully assist anyone else in my position. The cheap Euro adapter I bought off ebay appears to be of excellent quality but none of the attached fixings, pictures two and three, were needed and I had to cut off about an inch off the end of the threaded bar. The metal liner that has tapered ends was a perfect length; I just had to drill out the welder liner clamp from 4mm to 5mm. I also had to reuse the gas tube, replacing new on the adapter, as crimp fitted at the other end on the solenoid. On this welder I had to fix the front adapter mount sideways as shown to prevent the fixing holes interfering with an inner panel on this welder. I think it worked out quite well - please see pictures four and five. Just need to get the wiring confirmed and ready to test.

Does the black wire not connect to the threaded part on your new euro torch conversion, using the selection of nuts and washers to hold it in place? which is under the grey cap, that bit hanging off it looks like it was doing the same on your old torch as the threaded part on the new connector.

 

[rhino666]

Does your original torch operate a solenoid for the gas or just a valve. A friend of mine had to fit a solenoid when he converted an old Mig to euro connector probably where your other wire needs to go.

Hi Pedro, the earlier Sealeys seem to have the solenoid fitted to the welder already, rather than a function of the torch. You can probably make out the crimped fixings on the gas tubes that cannot be reused.

 

[rhino666]

Does the black wire not connect to the threaded part on your new euro torch conversion, using the selection of nuts and washers to hold it in place? which is under the grey cap, that bit hanging off it looks like it was doing the same on your old torch as the threaded part on the new connector.

I did not think so Chris, as not found any mention about reconnecting this thick black wire up anywhere on these Euro Conversion writeups but could be wrong. Hopefully someone can answer the original question about this this black wire that goes back to the rectifier, as well as where the second Euro adapter wire should go. It does seem a little unlikely that this big earthlike wire could be replaced with a light duty Euro adapter wire.

 

[eddie49]

On a Euro socket the entire circular brass cylinder is the "live" connection of welding power to the detachable plug of the torch. The power feed to this component, either from the DC rectifier output or from the output of a modern inverter MIG, is connected with a large cable tag sandwiched between the two nuts and washers on the threaded brass wirefeed tube, as @chrismac suggested.

The existing tag on the thick black cable from the rectifier may be large enough to fit over that brass tube, perhaps if drilled out. You will have to discard the grey plastic cap, and maybe use two half- rather than full nuts on the threaded part. Alternatively, a thick copper clamp wrapped tightly around the tube and bolted to the cable tag might work.
The brass cylinder is only supported by the black plastic shroud bolted to the front panel, the "grey cap" is not needed. Note that all the metal part is "live" and must not be allowed to touch any of the chassis or the front panel.

 

[eddie49]

Welders with attached ( non-Euro ) torches often have only one thin wire to the trigger switch, relying on "borrowing" the thick welder power cable inside the torch umbilical as the second wire in the switch circuit.
This single thin wire - often white - connects to the relay or contactor logic on the control PCB, and that board accesses the "second wire" by having a link to the positive output of the main welding rectifier, where the thick welder power cable is also connected. This link can be seen as one of the two red wires at the push-on tag at the bolted connection in the second photo of post #1.
When a Eurotorch with a 2-wire switch is fitted, one of the socket wires - red or black - takes the place of the thin white wire and goes to the control board. The other wire joins the positive of the main rectifier - where the push-on tag is.

 

[rhino666]

The other wire joins the positive of the main rectifier - where the push-on tag is.

Thanks for your contribution Eddie.
What do you mean by this please, photo of rectifier attached?
I assume it is connected in a different position and no continuity to the large black wire shown at the top?

 

[eddie49]

The rectifier has two AC inputs from the secondary of the main transformer. These are the two solid wires bolted to it at the bottom, wrapped in yellow and sleeved in flexible black.
Above that, in the centre of the photo, is the negative DC output, another solid wire in black woven sleeving, connecting to the inductor ( choke ), which is a second iron-cored coil on top of the main transformer.
At the very top is the heavy black flexible wire, which is the positive rectifier output and goes over to the MIG torch. On the same bolt of the rectifier there is a ring terminal with a push-on tag that has two thin wires. They both connect to the control PCB.
The second thin wire from the Euro socket, either the red one or the black one, should join to that tag. It is the same point as the large black wire, so in theory this connection could also be made right at the Euro socket, to the thick black wire and the threaded brass pipe. In that case the Eurosocket thin wire would be shorter and more direct, but maybe the junction of thin and thick wires would be messy...

 

[rhino666]

Thank you for that explanation; interesting and informative. My old torch clearly dealt with this by having the one connection which would appear to be logical. I will probably solder my small Euro Adapter wire to the large black wire fork that will be adjusted slightly with a file to fit over the threaded part of the Euro Adapter. I will use the non ferrous smaller threaded connector that came with the Euro adapter and some other fixings, probably ferrous, like the gold nuts and washers supplied with the adapter but smaller to fit within the grey cover.
Still struggling to get my head around why the Euro Torch does not deal with these common connections as one, rather than adding the extra feed.

 

[rhino666]

All completed and working.
I cut a piece of the inner grey mount out to allow the big black cable and fixings to fit inside; see photos.
Initially tried to solder the smaller black Euro Adapter wire to the big wire but thought better of it and soldered on a piece of wire that had a female spade to fit to the push on spade fitting on the rectifier and a wrap around to a spade that allowed the previously connected, two red wire female spade connector to be pushed on to that.
All seems to work fine with the white female spade connected to the Euro Adapter red wire and a quick test weld to confirm.
Thank you to Eddie and Chris for filling in the blanks with this job and hopefully someone in my erstwhile position will stumble on this thread and it will help them.