Is it ok to use bricks with indentation / frog ?

Is there any issue with using bricks that have an indentation (on one side) in them? Estonia doesn't have the biggest range of bricks it seems, and most places just sell bricks that have indents like in the below picture.



I am guessing the bricks could just be arranged in a way that the flat surface is always facing the burn tunnels, so it would be ok, but thought I'd ask first.

Many thanks,
Rob

I've never seen a fire brick with a frog. They are quite flat. Fire brick will almost always be a light yellow or whitish. Red or tera cotta type brick, can't survive the intense heat. Fire brick have a speckled look, as they are made from thousands of broken chunks that have been mixed with slip and re fired. This allows them to expand and contract through many cycles, without breaking up.

Regular bricks are fine for benches and other areas that don't experience intense heat.

You just saved me from making a big mistake Dale. I thought all these red bricks were good to go for this usage.

We picked up proper fire bricks today and are speckled, yellowish / whitish, made from thousands of chunks

Many thanks!
Rob

Rob Irish wrote:You just saved me from making a big mistake Dale. I thought all these red bricks were good to go for this usage.

We picked up proper fire bricks today and are speckled, yellowish / whitish, made from thousands of chunks

Many thanks!
Rob

I'm glad to be of service. I regularly check the postings of Jay C. White Cloud and Brian Knight in the building section whenever I plan things that are beyond my experience. It can save a lot of grief later, to run our ideas past the thousands of others on the forum. You would be wise to run your whole build plan past Allen Lumley and others. Maybe talk to him and then post your plans for everyone to critique. Santamax Antone, the Wisners and several others have a lot of experience with these things.

Quite often I see a thread, where a member posts pictures and says "Look at what I did". In many cases, they did something incorrectly, that could cause failure of their system. They say that two heads are better than one. A few hundred should be even better.

Did you get fire clay ? Regular mortar will also be destroyed by intense heat.

Dale : Thanks for thinking of me ! Masonry is something that I am working hard on to 'play catch-up'. Rob has several other posts, I will keep an eye out! Big AL !

Thoses bricks could be intresting to use to make a bell out of, with that "frog" towards the inside, to increase the internal surface area.

Cheers Dale. I would be stuffed trying to do this stuff without this forum.

I'm quite sure we got the right bricks. It took a bit to get there It seems like there are 20 words for fire in Estonia.. but none of them appear in the word for fire clay.

In case there is any other foreigner in Estonia looking for these bricks, look for 'Tellis Samott', somott meaning fire clay. You can get them at k-rauta or ehituseabc or interbauen.

These ones say they can go up to 1730c (3146f).

Will that be suffice? I recall in some places people saying temps of 2000c in a RMH. I don't think there are other options here for fire clay.

Looking forward to getting a prototype going, and will share some progress as I go. Thanks Dale. Big Al' has already been a great help.

Rob, that sounds like the chamotte, or shamott used in french and german. Or is it schamotte? Can't remember.

2000? Yep farenheit, they can go to 1200C°, lately we were talking with peter about reaching the 1980C° possible with wood, and he said, not without a fan. So 2000C° is not possible.

Ahh that makes sense Satamax. Good to know the bricks can handle it! How does the fan help - is it assisting the jet to increase the speed therefor more burn?

I did a look and Schamotte is the german one. Doing a bit more looking into it, the estonian word is Šamott, where that š sounds like 'shh' so they are basically the same. Mystery solved Thanks

Rob Irish : Thanks for the kind words, we all come here to learn, and if possible watch each others backs !
Like the old adage, ''A rising tide floats ALL Boats !'' Big AL