Door Autoclaved airated cement block

[cobblerdave]

Gudday
Got invited to a mates place in the break Great pizza for lunch. best roast lamb and veg for evening meal......Shame about his door

Mate... pretty ugly but I have got to admit the thing worked a treat...can't believe a piece of aluminum foil could stop that ply from burning!
Anyway I have made this one for him which is little tidier than my own.
[ATTACH][/ATTACH]
Its basically 75mm... 3in Hebel block bolted to a 10mm ply front (non gal bolts) another piece of 10mm ply screwed to the first covering the bolt heads which do get hot. The handles scewed to this so they two remain cool.
A revel is then cut into the hebel ..the stuff cuts like butter you can saw, chisel or rasp to shape. The door can then be used to seal all that heat when the fires out for some slow cooking. My original one has survived about a year quite well handles the heat alright. It has a crack in the hebel block (from a fall).... now I better build myself new one with the extra prettier wood to cover the boltheads.

Regards dave

[cobblerdave]

Sorry stuffed that ......

[brickie in oz]

Ditch the bolts and use silastic to glue it all together, the bolts will transfer heat.

[cobblerdave]

Gudday Al
What silasic? what sort of silastic is this,wait a min didn't you use silastic in your chimney damper?......what and were did ya get it


Regards dave

[brickie in oz]

Most silastic is good to 600c, I used roof and gutter silastic from Bunnies.

[TropicalCoasting]

Ive put a blow torch to roof and gutter silicone to try and get rid of it to solder a join on a gutter.It didnt burn after a few minutes I gave up

[david s]

When I tried a Hebel panel screwed to a wooden door it cracked in half after a couple of months. The problem is that it is made from Portland cement. If you could get an aerated concrete slab that used calcium aluminate cement that would be a better solution.
Al, can't see any silastic withstanding 600 C The stuff I use is good for 220 C I use it around my flue. It gets a bit soft when firing, but hardens on cooling and doesn't affect its sealing capacity. There are high temp silastics that will withstand higher temps, but they contain carcinogens and are way more expensive.

[brickie in oz]

Originally Posted by david s

When I tried a Hebel panel screwed to a wooden door it cracked in half after a couple of months.

Did it crack where the screw holes were?

The silastic holding the skid plate to my damper is still holding and Ive clocked the flue gasses at around 600c.

[cobblerdave]

Gudday All
Sorry for the late reply...
Davids thanks for your input....the crack I have in my temp. door is from dropping it ...ages ago... hebel is brittle. 10mm ply is flexible, drop the door and thats what happens. The bolts held it together so I kept on using it and yes the Hebel surface has stood up to the heat....I tend to use it also placed in front of the chimney as a heat sheld as well ...no probs. Its been a year now to so much for a temp. door.
So I think I will build Mod 111 for myself using silastic as the glue (thanks brickie) It should give me a flexible union between the ply and the hebel and stop the tendancy to crack. The hebel insulation properties should stop the worst of the heat from the silastic (thanks fornoa)
And if it fails .....the hebel used is worth $5 the other materials scrap and the effort involved....nothing.

Thanks all
regards Dave

[david s]

Brickie, my Hebel cracked right down the middle not where the screws were. The panel was only 1" thick. wouldn't use screws again, they get so hot they tend to char the the wood where they make the threads. I now use 3/16" 316 SS , much better. I prefer solid timber to ply as the glue holding the ply together does not like t he heat cycling, I think solid timber is better, I use Quilla.
Brickie, if your refractory was 600C it would be glowing red (doubtful), perhaps you were reading F

PS Tokyo is awesome. Saw an Italian fish restaurant with a WFO, will take a pic if I get back there again. There is EVERYTHING here.