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Paul.
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Firecracker welding, you used to be able to get special long electrodes for it, we used it a bit at a place I worked at years ago welding narrowboat hulls, before mig was as common as it is now,
https://books.google.co.uk/books?id...esult#v=onepage&q=firecracker welding&f=false
https://books.google.co.uk/books?id...esult#v=onepage&q=firecracker welding&f=false
Paul.
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You haven't missed much, I could make a better and faster joint with a 4mm iron powder rod, there were also gravity welding devices, an electrode mounted on an arm that held a conventional electrode angle and fed the rod as it burned away, that soon got thrown in the corner with the other junk as well,Heard about but never seen it done.
We made rods 700 mm long for use in those rigs (called ski's). Up in Sunderland at Austin and Pickersgill they had a jig thet held 24 together so they could be set off in turn. You couldnt weld stiffeners to deck sections any quicker.........but they still closed
They were used in many shipyards
We used to make them, pack them in metal cages because they had just come out of the drying oven, load a lorry and ship them up to the North East. They were still warm when they got there............those were the days
Yes but put it in the context of welding deck plates on oil tankers and making it an automated, consistent process and these machines were a step forward. As I understand it the Japanese were big on this in the late 60s and they used 7024 rods. One operative could keep half a dozen machines fed and be paid not too much. I'm sure TechnicAl will correct any points I've made which are in error.
Welding the bottom of the hull and the vertical sections would be a different story, but the owners of the shipyards would be into cost savings and consistency and they'd be significant on the flat sections of a big ship where automation could be fairly easily applied. The Japanese were very much into Demmings' ideas of quality. Also a lot of this is about having a good design you can produce with a minimum of variability and skilled labour, and which works pretty well. If you can make something pretty good, cheaply enough, it doesn't have to be the best that can be achieved to be a success.
I believe these days that they use robots using flux cored wire with gas for as much as they can, and that's quite a lot. Let's face it, if you want to build a ship of given standard, you want to minimise the use of skilled labour and use machines as much as you can. Far less messy. If you could pay a magician £500,000 to magic the welds together on a big ship, it would be a bargain, but you'd be casting round for magicians who worked cheaper. That's pretty much the story of welding replacing riveting.
Nothing to correct PTVor its what happened. It wasnt just Japan. We made 7024s for all over the place UK, Europe, America. We even made some that were measured by the fillet size rather than the wire diameter. They were designed to weld 900mm with a fillet "a" dimension of whatever. Many of the gaps to be welded were 900mm between the cross members. They would set them up but they wouldnt strike without a bit of help so they would ram a piece of wire into the end to start them off......a bit dangerous I suppose but they wore gloves.
All the link shows me is a blank square, with Firefox 41.0.1, which is fairly up-to-date. But the discussion turned to the first hesitant attempts at automated arc welding and it was at least a limited success for a reason - it was cheap on the scale they were doing it on and worked well enough.
If I've got the wrong end of the stick, I apologise, but claim in my defence that despite best efforts I didn't see what they were doing in the video. Perhaps my contribution was unwelcome? I've found this happens from time to time.
Richard.
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From where I was watching it looked really impressive. How they got consistency by holding it down with a size 10 was pretty good.
Practical maybe not but good to see non the less. (Never seen before). I don't think it is a procedure meathod of mma welding ptvor but it's very interesting what can be done with a stick set.
Practical maybe not but good to see non the less. (Never seen before). I don't think it is a procedure meathod of mma welding ptvor but it's very interesting what can be done with a stick set.
Richard.
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Ha ha yeah I'd imagine not the place to do it really. "I don't need a welding mask sir but I've got me fire proof boots on"
I actually thought the video was a fake because I would have expected the rod would have burned away too quickly to produce that much weld fill also there would have been a good chance of the slag running before the weld pool causing slag inclusions.
the snooper
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did you try it
the snooper
getting older by the day
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- Hull UK
the same as most of us, ive said I'm going to try stuff and never get round to it
