Door Autoclaved airated cement block

[cobblerdave]

G’day
cough cough sneeze …… this threads getting a bit old and dusty like me and the oven.
Well the sons put the door just out of sight beside the oven. By the time I found it it had been in contact with the ground and got the dreaded dry rot.
Used it a couple of times then the boards came straight of the rotten ply. The hebels hopelessly cracked now so I built a new hebel back to go on the hardwood boards directly as they have no rot.
Oh bugger $20 for the hebel not $5 and $9 for the gutter silastic. Recon it’s worth it as I hope to get another 10 years out of this one lol
Regards Dave

[cobblerdave]

Gday
what can I say...... Champion!.....
regards dave

[seannieboy71]

CobblerDave,

Your oven door inspired me. Although not exactly like yours, your use of aerated concrete reminded me that I had a few insulation firebricks laying around that I might be able to use in a similar manner. I cut the bricks in 1 inch thick slices and glued them to a wooden door structure. Then I glued a cake pan to the IFBs. The pan fit perfectly into my door opening. I filled the pan with ceramic fiber blanket. I used 700F capable gasket making silicone as the adhesive. The door works great.

I attached some pictures.

[cobblerdave]

G’day
works with silastic because you have the airated cement sheet to protect it from the heat! Used gutter sealant because it’s designed for exterior use. Mines still together after 8 or 9 years now battered yes but still doing it’s job.
regards Dave

[Geordy05]

Hi Dave & Others,
I found this thread describing how to make a door from an aerated cement block very helpful and it has prompted me to start my own project - thank you all. I do have a question about the suggestion to use "roof and gutter silastic" as an adhesive. Did you use straight roof & gutter silicone (which I always assumed was a sealant only) or did you use something like liquid nails (not sure this would be safe?)
If any of you could let me know what product you successfully used that would be a big help to this newbie!
Thanks,
Phil

Phil, I think any high temp silicone adhesive for fire place installs etc. would work. The handle screws I would think could be screws into the blocks just not all the way through? Not certain on that just a thought I was considering. May transfer to much heat to handles.

[Geordy05]

Great thread. Thanks for the vision and insight.

[PhilMason]

Hi Dave & Others,
I found this thread describing how to make a door from an aerated cement block very helpful and it has prompted me to start my own project - thank you all. I do have a question about the suggestion to use "roof and gutter silastic" as an adhesive. Did you use straight roof & gutter silicone (which I always assumed was a sealant only) or did you use something like liquid nails (not sure this would be safe?)
If any of you could let me know what product you successfully used that would be a big help to this newbie!
Thanks,
Phil

[cobblerdave]

Re: Door Autoclaved airated cement block

Gudday
Gudday
Finally got around to fitting that hardwood face (only taken me 6 mths)

A nice piece of blackbut come my way with the handles it looks pretty good.
The doors still together the silastics held up. I now realise that the oven door usually goes on with the temp about 350 C so the hebel must protect it to that temp at least. With no bolts through the door these no hot spots and the surface of the door and the handles are always cool. The only disadvantage is of course the hebels brittle I have one small chip in one edge it doesnt effect the doors operation and you certainly can't see it so I can live with that. I made a wood door just out of a packing crate as I could find little about them on the forum. It was a lot of fun and it worked well enough so I have the following link which might be of help to somene ( the wood doors at the end of the thread)

http://www.fornobravo.com/forum/f17/maybe-silly-question-but-here-i-18514.html

Regards Dave

[cobblerdave]

Re: Door Autoclaved airated cement block

Gudday All
Got the oportunity to flash the oven up only 3 times since the new door was made, due to rain, general business and more bloody rain!

As you can see the silastic doing its job and the doors still together!
Theres a coupla dings and chips , but I expect that. I noticed that the bright white colour has deminished a bit and its starting to get a lite brown colour in sections...the old door was well browned off. Its also lost the powdery white residue of freshly cut hebel gives off.
I'll now take off the extra layer off plywood and replace it with a hardwood face and oil it. I'll also carry a strip of wood around the edges to protect the hebel edge but just off the brick so it won't burn. I also scored some new handles to replace the old ones off my tool drawers.


Regards Dave

[Aussie Pete]

Re: Door Autoclaved airated cement block

that sounds like a plan Dave, show us some pics when your done. I'm still yet to make my door, yours will be interesting to see how it comes up.

[cobblerdave]

Re: Door Autoclaved airated cement block

hey Dave, i think i have read somewhere that you could also use calcium silicate board as a door...is that right?. interestingly..which would be lighter...hebel or cal. sil. board?

Gudday Pete
Have some cal sil board and its real light... lighter than hebel. Real soft to. My problem with it it is that it really needs to be covered with a metal skin. My metal working skills are not that advanced and the door that I did see "proffesionally" made was worth $300. Bloody beautiful job looked great And you can just guess what ....gets real hot.... not what you need from an insulated door. Definitly need to separate the outer and inner parts!
I'll keep the cal sil board and this can be on ongoing project.
Meanwhile the hebel door has proven to work well ....is easy to make...cheap and the parts easy to obtain.
Now that Ive written this out I have a thought... perhaps a composite could work an outer wood door with a metal protective layer on the inside to protect the cal sil.... could work

Thanks Dave

[cobblerdave]

Re: Door Autoclaved airated cement block

Gudday
Using silastic I glued the hebel to a face made of two pieces of 10mm ply screwed together.

2 pieces so if the silastic didn't work out I can unscrew them bolt the hebel on them rescrew the secound over the top to cover the hot bolt heads. I used 3 in ( 75mm)hebel as i did in the first and cut a 1 in (25 mm) revel
Too bloody heavy I was sure mark 1 didn't weigh this much so I weighed it ....12.6 KG.....Decieded that was getting too much so I set about reducing the weight

Cut 25 mm off the whole thing and recut the revel weighed the door again.....9.4 KG thats better and the thing even though still quite heafty is usable. as you can see I used hand tools to do this it real dusty stuff and power tools would just make a big mess. Its real easy to saw and rasp Ive carved things with it before

Final door also has a the ply cut higher than the hebel on the bottom and a piece of alum angle to protect it from the hot bricks. I be testing this one to see that it works and I'm on the lookout for some interesting hardwood to replace the outer piece of ply with.
Sorry some of the photo got mixed up but thats all to date

Regards Dave

[Aussie Pete]

Re: Door Autoclaved airated cement block

hey Dave, i think i have read somewhere that you could also use calcium silicate board as a door...is that right?. I think it may have to be covered with steel sheeting of some sort to help protect from the initial fire/heat.
this is what i was going to use, i dont think its too expensive either, about $25 a sheet.
interestingly..which would be lighter...hebel or cal. sil. board?

[cobblerdave]

Re: Door Autoclaved airated cement block

Gudday all
Problem wih building a temperary anything and it works... you keep on using it and never build a "proper" one.
So I've made my mind up the door has to get pulled apart or I'll never build another


Pulling it apart was interesting the hebel surface was basically a bit smoke stained and chipped but still in good condition not deteriated at all from the heat. The ply that it was bolted to was also still good I 1/2 expected to find some heat damage around the bolt holes but there was none. Did however showed charring on the bottom edge where it was in contact with the hearth bricks at the entrance no scorching anywhere else so the hebel did its job.
So I started Mk 111 door this time using silastic instead of bolts

[david s]

Re: Door Autoclaved airated cement block

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.