The Naiad Voyages

Mark Austen

2016.04.22 - Maybe It’s Not Me

Having decided that I’m not going to rush the relaunch and that I’m also not going to pay someone to make the tabernacle at the prices I have been quoted, I started looking around at why it was that I can gas weld with oxyacetylene but can’t arc weld. There are lots of instructional articles and videos on the Internet and I’ve been reading around the subject as my boat-work for today.

Well, it seems that it might not be me after all. The arc welder I used all those years ago, more than 30 now, was what is affectionally known as a “buzz-box” since that’s pretty much what it did when switched on. My problem is that when I try to arc weld either the arc goes out, or the stick gets stuck or the puddle doesn’t form properly. Needless to say these are all known problems and can be attributed to one or more of three causes. Firstly, the open-circuit voltage of the welder is too low and by too low they mean under 60 volts. Secondly the current is not sufficiently high and thirdly cheap welding rods are being used. Notice that not one of these is the lack of experience of the welder.

That doesn’t mean to say that an inexperienced welder will not suffer these problems, they will, but it does mean that they will get better with practise whereas with one or more of these causes they will probably never get to weld properly.

I don’t have the welder anymore, it overheated once too often and stopped working completely but as I recall it had an open circuit voltage of 48 volts, the maximum welding current was 90 amps and the welding rods were the cheapest I could find.

So maybe it’s not me at all. Maybe I can weld with decent equipment and practise.

I’m going to find out.

There are many welders for sale on the Internet and armed with the minimum recommended specification of 70V open-circuit voltage, at least 130A welding current, inverter technology, DC output and a duty cycle of 60% or better It was a simple job to eliminate most of the welders under £150 from consideration.

What’s “duty cycle” I hear you ask. Well, that’s a measure of how long you can continuously weld in a 10 minute period at the maximum welding current before you have to stop and let it cool down. So for a 60% duty cycle you could weld for 6 minutes and then let the welder could down for 4.

Not surprisingly there were welders available that met the criteria at a price of more than £200 but very few under that. I was resigning myself to spending a lot of money on a welder when I found one that exceeded my minimum specification and yet still only cost £110. I could hardly believe it. The downside is that it is made in China and most welders from there do not have a good reputation. Still, I read around and looked the reviews and whilst you would not use this for professional welding, it seems to be ideal for the sort of welding I want to be doing.

And it is tiny! Seriously small. It measures round 100mm wide, 150mm high and 250mm long, or 4” x 6” x 10” and weighs an amazing 2.6Kg or 5.7lbs. The unit I had way back must have been 250mm x 250mm x 250mm (10” x 10” x 10”) and I could barely lift it.

One of these remarkable machines is on its way to me even as I write. Along with the other paraphernalia that you need, face mask, welding rods, lots of welding rods and good quality ones this time and a chipping hammer except the hammer has already arrived.

I have a fair bit of scrap steel lying around the place and I’ll use most of the welding rods just practising so that when I make the tabernacle I’ll be able to make the 8 welds well.

That’s all I need, just eight small welds and the basic tabernacle will be done. If I decide to weld on the cleats then there will be more welding to be done, but I may just use bolts or rivets instead.

Some photos taken from the advertising blurb for the mini-welder.