Vermiculite (Grade #3 or #4)

[david s]

Re: Vermiculite (Grade #3 or #4)

Those bricks look pretty clean to me. The best way I found was to use a tomahawk to chip off mortar. It's tough work, but worth it if the bricks are cheap enough.

[Gulf]

Re: Vermiculite (Grade #3 or #4)

Those bricks look pretty clean to me. The best way I found was to use a tomahawk to chip off mortar. It's tough work, but worth it if the bricks are cheap enough.

And just a stiff brush (whisk broom) to remove the loose material before laying the brick .

[Saovicente]

Re: Vermiculite (Grade #3 or #4)

Thanks Gents.

PS: Gulf I enjoyed your build, especially the design and implemantions of the damper.

[Ash71]

Re: Vermiculite (Grade #3 or #4)

For ease of use get what you feel comfortable with. For instance, I'm not sure which grade I used but, I used some (and I'm happy with the results). Try not to get to caught up in what you use or you'll end up like me......... Stuck at a stage because you want your oven to be the best it can be ( I'm having trouble sourcing the right products at a price I can afford ). I haven't done a lot with my project of late because of that fact. If I had of made the decision to use solid common bricks instead of committing to use the RIGHT bricks, perhaps my oven would have been finished by now. You're on the best track you could be on......like having your first child, listen to all the advise your given and make a decision that you are comfortable with. The best advise I can give is no matter what type you use just try not to breathe in the dust, you only have one pair of lungs.

[kanoer54]

Re: Vermiculite (Grade #3 or #4)

Looks like you have a gold mine of old bricks. My old house has a lot of what the old masons described as salmon bricks. I use a dozen or so for the front decorative arch....for what it is worth.

Looking forward to your build. Keep us posted with pics.

jon

[cobblerdave]

Re: Vermiculite (Grade #3 or #4)

Gents,

I recently acquired some olden chimney bricks (average 7lbs each).
My thoughts are to use them for the outer arch, brickies thermal mass idea, enclosing the oven for the vermiculite payload or decorative means.

Any better ideas of the best way to utilize them would be appreciated.

Any thoughts on the best method to clean them up a bit, other than scraping the dried mortar off ( I want to keep the aged look)

I have read pics are welcomed, so I added one for the visual fun.

Best regards,

Sandro

G'day Sandro
Re brickies use of pavers for thermal mass.
Brickies oven used pavers 50 mm ( 2 ins)thick and firebrick slabs 35 mm ( 1 1/2 ins for his hearth. Most ovens use splits 50 mm ( 2 ins ) or fire brick on the 75 mm/3 in edge. You can overdo the thermal mass on your hearth and turn your oven from a great all rounder to an oven more suited to mass bread production.
The floors are thinner cause heat goes up and the floor depends on the heat from the coals and that reflected from the dome. It takes the most time and fuel to heat. I have 75 mm firebrick hearth I believe that's as much mass as I can fuel and would be just happy with splits a 50 mm.
Regards dave

[Saovicente]

Re: Vermiculite (Grade #3 or #4)

For ease of use get what you feel comfortable with. For instance, I'm not sure which grade I used but, I used some (and I'm happy with the results). Try not to get to caught up in what you use or you'll end up like me......... Stuck at a stage because you want your oven to be the best it can be ( I'm having trouble sourcing the right products at a price I can afford ). I haven't done a lot with my project of late because of that fact. If I had of made the decision to use solid common bricks instead of committing to use the RIGHT bricks, perhaps my oven would have been finished by now. You're on the best track you could be on......like having your first child, listen to all the advise your given and make a decision that you are comfortable with. The best advise I can give is no matter what type you use just try not to breathe in the dust, you only have one pair of lungs.

Thanks Ash,

I appreciate the advice. I too am in a precarious position of wanting the best of products on my first outing but faced with a limited budget to get the oven done right. I will spurge on some on the products recommended. One by Davis S to use stainless steel needles and poly fibers) ooohh the shipping is a killer ($22 for the product - $10+ for the shipping). As we are the newbies: Do keep me updated on your progress, struggles as we learn from the masters in creating a new age of ovens with auto temperature (K) reads, internal oven light, wireless cam, heated lamps to the side (for the dough) and the wish list keeps growing (Where is Santa when I need him most)

Best Regards,

Sandro

[Saovicente]

Re: Vermiculite (Grade #3 or #4)

I appreciate the look. I had to bare a chilly NE winter day to get my hands on those babies. All I know about the bricks are that they came from the tear down of a chimney and I have no idea what they are called and if they are good enough to use as part of my hearths thermal layer....Still searching.

I will definitely keep everyone up to date on my built. I will be starting a new thread in a month or so with pics as I break ground on the built.

Best Regards,

Sam

[Saovicente]

Re: Vermiculite (Grade #3 or #4)

G'day Sandro
I have 75 mm firebrick hearth I believe that's as much mass as I can fuel and would be just happy with splits a 50 mm.
Regards dave

Dave,

I appreciate the reply. My concern was, since I will not have any ceramic boards under the firebricks. I wanted to insure I could maximize my options without breaking the bank. The pavers I have are from the tear down of an old chimney (each is about 2" thick).

The original plan was/is to follow the Pompeii method of having 3.5" of slab, I am thinking of using a reflective insulator (normally used under the concrete of a heated floor to insure there is no heat loss passing below the slab) 4" vermiculite, 2" pavers and 9x4.5x2.5 firebricks > giving me a total 4.5" of mass.

What do you think? Should I replace the 2.5" firebricks with 1.5" or just keep the 2.5" a and remove the pavers.

Your thoughts are appreciated,

Best regards,

Sandro

[cobblerdave]

Re: Vermiculite (Grade #3 or #4)

G'day
Those reflector type insulates usually are only effective when used in an air space, so I find the use you describe as unusual. Anyway effective or not if you have some why not , it will make a great moisture barrier under the insulation as well.
Again I'd would lose the paver layer and keep the mass down in a more usable range. 2.5 in (65mm) is a good amount of mass in an insulated oven.
Regards dave
By the way ceramic board is easy to use but expensive in comparison to pearlite/ cement.
But still 4 ins of pearlite/ cement insulates as well as 2 ins of ceramic board!

[Toomulla]

Re: Vermiculite (Grade #3 or #4)

Reflective (foil)insulation is usually composed of a thin aluminium foil layer and PVC layers and is unlikely to remain intact in the high temps your oven will achieve, even below the floor so it would pay to check the manufacturers recommendations on operating temps

[cobblerdave]

Re: Vermiculite (Grade #3 or #4)

G'day
It's under the insulation layer, not under the brick. If it was it would not do as you have described.
Regards dave

[Toomulla]

Re: Vermiculite (Grade #3 or #4)

Yes under the insulation should be ok although I would not expect a long life in contact with the cement If it is the roof ceiling product as it will not like the lime but if you have it you have nothing to lose

[cobblerdave]

Re: Vermiculite (Grade #3 or #4)

G'day again Toombula
It's been described as a produced used under the cement slab to contain the heat from underfloor heating. I never had experience with anything like that, sarking/ sisslation yes but that's a different beastie altogether.
Regards dave

[Toomulla]

Re: Vermiculite (Grade #3 or #4)

Sounds good for the use not much call for underfloor heating the North Queensland