My story and a quesstion

[NickMig]

Hi,

Hope some of this helps others - and a question at the end.

I'm not a welder but on a whim last week I bought an old "not working" and "badly butchered" Clarke 100en mig welder with gas conversion for few quid.

Note the Clarke manuals don't show the actual circuit layout but more like a generic one.


1. Fully degreased it inside and out with paraffin.
2. E1285-4 PCB faulty (very bad previous repairs).
3. 33R wirewound resistor open circuit replaced £0.15p.
4. Thyristor TYN 408 burnt out (no longer available).
5. Replaced with equivant 400v 8A TIC116D Thyristor £0.77p.
6. Several solder bridges between tracks tidied up.
7. Two tracks replaced with wire.
8.. Torch hanging off - Remade joints and reassembled.
9. Wire feed reassembled correctly.
10. Replaced all cabinet screws with screws of the same type.

Now its working fine (welds and thermal cut out kicks in when it should) and it looks good (But I might repaint it).

(NOW! comes the hard part learning how to use it!)


So finally a few questions to those who have an older version of this welder.

? When you turn ON the power switch does your power switch light up?
? When the thermal switch kicks in, what does your switch then show?

And finally does anyone know the colour code for the Clarke paint and how to calibrate the preset potentiometer on the PCB.

Thanks in anticipation

Nick

 

[Endacy]

Hi, welcome to the forum!

Nice work fixing an old MIG, on my newer Clarke welder the switch lights up only when the thermal cut out kicks in (or should, not sure i've ever managed it). Seems daft that it doesn't light up when it's turned on!!

Is your welder red? I painted some stuff with car paint from halfords (old though) and it was Rover 'signal red' - it's pretty close to Clarke red - not perfect thugh, depends how good you want. Not sure they'll still sell this particular one though to be honest, the can was pretty old.

 

[d c]

i bought a used clarke 90 and the on off switch glows amber when switched on. havent got it to overload yet,still learning and doing short bursts. as for colour tahke a panel to a car paint / refinsher supllier and they should have a colour swatch which you can match the colour, some can scan the colour and match it

 

[malcolm]

There were a few variations on the light in the switch. Some were a power indicator. It was only in the last 10-15 years it became an overload light.

For setting the potentiometer set the power to lowest and the wire speed to lowest and adjust the potentiometer so the wire just crawls out. If that doesn't leave you with enough range for thick stuff adjust it for that.

 

[NickMig]

Thanks Endacy,

Yes its been a bit of fun this week working out how it works and waiting for a couple of electrical components off ebay:

Its a blue one, there must be a colour code somewhere, unfortunately I don't possess a colour chart.

As you said reaching thermal cut out is extreme on any electrical equipment.......................

I checked the thermal cut out switch using the following method:-

Removed the switch from the Diode packs aluminum heat sink.
Bolted it to a piece of scrap copper
Measured it with my meter (cold it is closed circuit)
Left it bolted to the scrap but wired into the welder.
Checked that the welder worked.
Then played a gas torch onto the scrap until the switch opened.
Checked that the welder had stopped. (hot its open circuit)
When the copper cooled the switch closed and the wire feed motor and welding ability returned.
Then reassembled.

This afternoon I turned a piece of brass and bored it 1mm to replace the feed in side plastic guide tube on the welders wire feed.

Anyone got an idea how to calibrate the preset potentiometer on the pcb.

Thanks in anticipation
Nick

 

[NickMig]

Thanks Malcolm

Thats exactly what I wanted to hear.

"My" switch glows amber and stays amber when thermal cut out occurs.

Thanks for the information regarding the preset, I didn't want to alter it until I knew what I was doing.

As the welder had been butchered, I wasn't sure if this had been altered as well.

So all I need now is the name / code number whatever of the Clarke blue.

Thanks
Nick

 

[Robotstar5]

Here are the RAL colour charts if thats's any good?

 

[NickMig]

Hi Robotstar5

Ummmm, that site is very interesting, but I don't think that its possible for me to print off the colour charts and confidently use them to get a paint mix made up.

Interestingly I see its possible to buy the BS gloss charts but at £49.99 a pop.

Thats several times more than this project has costed me up to now.

So back to begging does anyone know the code number or name of Clarke blue?

Thanks in anticipation
Nick

 

[pedrobedro]

Hi Robotstar5

Ummmm, that site is very interesting, but I don't think that its possible for me to print off the colour charts and confidently use them to get a paint mix made up.

Tell the paint shop the Ral number and the paint should be close enough for what you need.

 

[NickMig]

Thanks Pedrobedro,

I think I will take "d c" advice and when I'm in town I'll pop into a paint shop with a side panel and ask if they would use their swatchs to match the colour.

All this may seem 'OVER THE TOP' but .. hey I got the welder for a song ... and I'm retired so I have plenty of time to research, hunt and barter bits and pieces.

May take a while but when I "know" the colour, I'll keep my eyes open for it (probably not a stock colour or maybe it is?).

Next job is practice on some scrap, and keeping my eyes open for a pub CO2 cylinder, regulator and some quickstar couplings I guess?

Thanks everyone.

Nick

 

[rhubarb]

Hi Nick did you ever find out the colour of the clarke mig welder i just bought a blue one its a bit rusty wanting to paint it

Regards Rhubarb.

 

[Dev]

Given that he posted 2 years ago and hasn't been heard of since I wouldn't hold your breath.