What a load of blocks

[paul]

I've got access to a bunch of duff storage heaters (the old economy 7 overnight type). Does anyone know if the blocks therein are likely to be any use for the construction of a brazing hearth?

TIA

[ron]

Hi Paul
That's what I use.
Ron

[jgb7573]

Should be fine. Mind you, I use ordinary house bricks for my brazing hearth. If they're kept dry they last reasonably well and are cheap to replace.

[paul]

I'm using patio blocks at present but I'm a bit concerned as some have suggested they might explode. Eeek!

[baggo]

I use lightweight thermal building blocks which seem to work very well. Cheap enough from the local builders merchant.

[ron]

Paul
You need to watch the firebricks for that as well, don't leave them outside to get damp
Ron

[houstonceng]

Someone commented - can't remember where - that "bricks" from Night Storage Heaters were designed to soak up heat during the night and release it slowly during the day. Consequently, they soak up heat from brazing ops.

What you need is something to reflect the heat back into the work - like ceramic chips.

I suppose you could build the hearth from the blocks and fill it with ceramic chips.

Of course, this could all be "an old wives tale"

[AndrewP]

Spot on Andy, night storage heater blocks are designed to do exactly that, not really what we want. They can form a nice heat resistant layer behind the correct blocks/chips though.
Best source for the blocks is probably a potter - they seem to go through kiln liners like there is no tomorrow and those blocks are just right. Whatever sort - keep em dry! as others have said.

Plain bricks are around a fiver each from somewhere like Potterycrafts if all else fails.

Cheers, Andy

[Chris Kelland]

Hi All,

As Baggo says Thermalite blocks work a treat. I usually go 'skip diving' for odds and ends and they cut with an old wood saw.


Chris.

[stoney43]

wow got 50 thermalite blocks round the allotment must go down and rescue them

[paul]

Hehe, my workshop/garage is lined with Thermalite type blocks... now I wonder if I could knock a couple out without doing any structural damage