Sunday, May 13, 2007

Gas welder


So, how was your day?
I was fiddling about with the door frame again and got another piece glued on.
I experimented with a tiny bit of glass engraving the other day as a little feature in the center of the interior molding and that seemed OK, so having that fitted in meant I could go ahead and glue the molding on.
Started truing up a piece of zelkova for a counter top that had once been used for a similar purpose but left out in the weather for many years to warp away to its hearts content. More of that activity of squinting across two straight edges to sight the twist and planing back to create a flat surface all the way around the rim making it easier for the counter to be screwed down to some support in the walls when it is fitted.
I was about to finish up for the day, but decided to have a quick go at gas welding to continue my moves toward getting back in practice. I had forgotten how much fun that is. TIG welding is similar, but there is all that UV light about. The other day I was having trouble with gas poping and so was the welding torch. Couldn't remember whether that meant a problem with the metal or the gas, so went on a little web search for it and found a nice page by some guy building his own light aircraft describing the gas reaching combustion temperature in the nozzle prior to exiting causing the explosive pop. Just hold back on the torch and let it cool and it is fine. If it still happens shield the torch or up the gas flow to keep it cool and give a hotter flame so you can keep the torch further away from the work. I also found a load of pages saying that it was to do with the type of steel being incompatible, due to differences in composition, just on the wrong track or a separate issue. It makes sense that if you can relight the acetylene just by playing the gas over metal that isn't even very red, then the stuff is reactive enough to blow up in the nozzle. Anyway having swept the floors pretty clear of shavings it seemed safe to risk a few pops of metal about the place. The welding work was just filling big gaps on some little flower shaped light shades I started months ago when I was trying out the fly press. Either copper clading for the foot of the door jams or back to the table legs tomorrow, I'll see how the mood takes me.