Announcement

Collapse
No announcement yet.

28" homebrew cast oven in walled enclosure Belgium

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Kris S
    replied
    Originally posted by Kris S View Post
    25kg vermiculite + 25 kg perlite 35 +/- 2/3 used
    25kg bags portland cement 2 7.5
    25 kg bags sand for dome mould and homebrew 3 5
    25 kg bag fireclay 1 17
    +/- 10kg hydrated lime 0 free


    Looking back at the used materials overview from my post #102 I bought 25 kg fireclay, I don’t remember exactly how much I used but I still have some left, maybe a quarter to a third.

    I can weigh what’s left over so we know for sure, I’ll try to do that.
    Just weighed what was left of the fire clay: I used 15kg.

    Leave a comment:


  • hughesyourdaddy
    replied
    Thanks for the replies everyone.

    Leave a comment:


  • Kris S
    replied
    Just realized I haven’t uploaded a pic of the finished oven yet apparently, so here is one.
    Actually I still have some things left to do in order of importance:
    • Make a permanent chimney cap to keep rain out (the plastic bag solution is horrible)
    • Make an outer ‘storm door’ to keep rain out of the entry
    • tidy things up around the roof edges (currently just screwed a wooden board in place), don't know exactly what/how though...
    • Apply a cement render over the base
    • Paint the whole thing (better protection against rain than just a cement render)
    • Make an insulated door for longer heat retention
    • next year add a work bech / table top to the right
    Click image for larger version  Name:	20211023_132350.jpg Views:	0 Size:	283.6 KB ID:	442846
    Last edited by Kris S; 11-02-2021, 01:44 AM.

    Leave a comment:


  • Kris S
    replied
    25kg vermiculite + 25 kg perlite 35 +/- 2/3 used
    25kg bags portland cement 2 7.5
    25 kg bags sand for dome mould and homebrew 3 5
    25 kg bag fireclay 1 17
    +/- 10kg hydrated lime 0 free


    Looking back at the used materials overview from my post #102 I bought 25 kg fireclay, I don’t remember exactly how much I used but I still have some left, maybe a quarter to a third.

    I can weigh what’s left over so we know for sure, I’ll try to do that.

    Leave a comment:


  • AndreasP
    replied
    I just finished casting my 32" dome and gallery. For done and gallery I used:
    • 200 lbs of sand for the dome
      • I used some of the sand I used for the dome mould to cast the gallery a few days later, probably 30 lbs or so
    • A bit less than 50 lbs of clay - I used up the complete 50 lb bag but used a few handful in the sand to build the mould for the dome
    • Not sure on the portland cement and lime, but less than a bag each
      • maybe 2/3 of a 94 lbs bag
      • maybe 1/2 of a 50 lbs bag
    Maybe this helps.

    Leave a comment:


  • UtahBeehiver
    replied
    Look at Nick JC build, he did a really nice cast build and detailed out his materials.

    Leave a comment:


  • hughesyourdaddy
    replied
    Hi Kris,

    Great build! I'm preparing to build an oven and will use yours as inspiration because I want to build 28" too. Can you remember how much clay you used in the homebrew mix in the build? I can only source by the kilo where I am so it would be great if you could let me know. Thanks.

    Leave a comment:


  • AndreasP
    replied
    Kris, David, thanks for your feedback. I think I will stay with my original plan of a 19" opening for a 32" diameter oven. I could always stand up some firebrick along the side of the opening if I want a smaller opening.

    As far as the floor height, I have a bit of a challenge. There is a big height difference between me and my wife. I am sure I will be the one cooking in the oven, so I have chosen my elbow height for the cooking floor.

    Leave a comment:


  • david s
    replied
    I agree about the more generous oven mouth. Mine is 16” wide, but for a 21” diameter oven that’s pretty wide for a small oven, but as it’s fuel consumption is so low it’s no trouble to flash it up. Plenty of retained heat for roasts and bread etc.
    I think for working height you just get used to whatever you have.

    Leave a comment:


  • Kris S
    replied
    Hi Andreas, I went for 19” width and 8.7” height.
    If you can, I would advise choosing opening width over pondering about eventual heat loss.
    With my rather small 28” diameter oven a 19” opening is pretty large and I probably lose quite some heat, but I’m happy I didn’t go smaller than that, it would not be practical.
    19” is adequate but not luxurious, any smaller and it would annoy me I think.
    I have done pizzas, a roast chicken, pasta sauce, some vegetable casseroles, 2 breads, some bbq ribs…

    Something minor I would do different is have the oven floor higher, now the height of the floor is about 130cm I think (should remeasure to be sure), I would add 20cm to this, because I have to bend a little too much for loading and unloading. (I’m 1m87cm tall). But aesthetically I went for a little lower, should not have done that.

    Leave a comment:


  • AndreasP
    replied
    Kris S , What opening did you go with? I am planning my oven and hope to cut the brick this weekend, then cast the dome. I am planning on a 32" internal diameter and am going back and forth between a 17" and 19" opening.
    Larger opening = easier access
    Smaller opening = more thermal mass, should retain heat better for cooking
    Have you used the oven with your door size for pizza yet?

    Leave a comment:


  • Petter
    replied
    Originally posted by Kris S View Post
    Fair enough, I'll see if I can find it anywhere.

    Sodium silicate goes under a lot of names, and I see both potassium silicate and sodium silicate products are being used for waterproofing (not my purpose), so can either of these be used for what I want to do, or should I specifically search for a sodium silicate product (with the correct CAS nr. 1344-09-8).



    on a side note: the oven seems to have survived saturday's pizza firing without further cracks, but I'll wait and see this week when it's fully cooled down...

    You can use either, they form Silicate networks when cured.

    Great that no more cracks formed. I have some 10-15 fires at 1100-1300 F dome temperature with no issues no. The cracks appeared at fire 2-3 during cooling.

    Leave a comment:


  • Sidetrack
    replied
    Originally posted by david s View Post
    Hi Chris,

    Any large refractory section is vulnerable to cracking, primarily because of the difference in thermal expansion. A one piece dome in particular, using wood as a fuel is particularly susceptible. For this reason most cast oven manufacturers offer their ovens in multi piece sections. This makes things more manageable and less weighty sections. For mobile ovens some manufacturers offer a single cast dome as they're less likely to have problems with road vibrations. When I first began to build ovens I used a single piece cast dome, but now produce a 3 piece dome. Unfortunately this requires much more work to create a mould, particularly if the sections are to be step joined. This is hardly worth the effort for a single cast oven, the simplicity of the single cast, in situ, over a sand mould has way more advantages. The single cast does however have a tendency to produce a crack, just like yours has, which runs vertically right opposite the oven mouth.
    Would it be possible or practical to set some paper or foil into a cast-over-sand dome to mimic a multi-section dome and control where the inevitable cracks form?
    Click image for larger version

Name:	Expansion Joint.PNG
Views:	249
Size:	37.7 KB
ID:	441641

    Leave a comment:


  • Kris S
    replied
    Fair enough, I'll see if I can find it anywhere.

    Sodium silicate goes under a lot of names, and I see both potassium silicate and sodium silicate products are being used for waterproofing (not my purpose), so can either of these be used for what I want to do, or should I specifically search for a sodium silicate product (with the correct CAS nr. 1344-09-8).



    on a side note: the oven seems to have survived saturday's pizza firing without further cracks, but I'll wait and see this week when it's fully cooled down...


    Leave a comment:


  • Petter
    replied
    I understand your questions but I'll not answer them. If you need to ask, you don't have the knowledge to deal with these type of chemical. I don't wish to be unpolite, I only care about your health. Manufacturing this is really nasty work, no matter what any you tuber say or show. Being outside with tail wind, mask, glasses and so on is not enough. I did my own but will never do it again. Buy a liter, it is more than enough and should cost less than $10. Store bought SS is in the 35-45 % solid range.

    ​​​

    Leave a comment:

Working...
X