Chimney work

The chimney in the farmhouse has a very ill-fitting "register plate" - this is also known as a "throat plate", basically something to stop all the heat from the fire going straight up the chimney instead of out into the room. The present one is an old bit of galvanised iron, cut very roughly to the right shape, then pushed up the chimney until it jams. It has a round hole in it for the flue pipe. But as the old flue was 125mm and the new one will be 150mm, there were several good reasons to change it.

I salvaged from Pigeon house the old framework that once supported the heating oil tank - fairly substantial angle iron, possibly welded up by my father-in-law forty or more years ago when the the heating was converted to oil. I had to cut it up to get it into the car, but in any event it was the wrong size: too short for the fireplace, which is nearly 2.5m wide. I cut the old framework into two "L"-shaped pieces, on the basis that this would save me the job of making anew all four corners. I then had to extend each of the long legs of the L, by welding on extra pieces of angle - the former legs of the framework were just about the right length.

Some of my welds were better than others.....



..... I'm afraid that is one of the better ones. Best not to ask about the worse ones. Though I think I am beginning to get the hang of it. It's a bit tricky where the two pieces of metal are different thicknesses because of extensive rusting. But the new register plate framework only has to support a couple of sheets of insulation board, and as long as it stays together it'll do.

Here's the finished framework before I painted it:



I've gone over it all with a wire brush on the angle-grinder, and smoothed off the rough edges. Then I gave it a coat of black paint that is supposed to contain a rust-inhibitor - another one tomorrow and by Friday I should be able to start sticking it up the chimney. The intermediate cross-pieces were part of the original structure: I only had to cut them to length and weld them into place at one end. The middle ones - where the chimney will go, through a metal plate - were a bit short and had to be extended.

I had to get thicker wire for the MIG welder - 0.8mm - as the original wire at 0.6mm just wasn't forceful enough to penetrate the metal.