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Forum topic by AlaskaGuy posted 06-17-2019 03:51 PM 540 views 0 times favorited 22 replies Add to Favorites Watch
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AlaskaGuy

5317 posts in 2731 days


06-17-2019 03:51 PM

I’m building a Kamado Joe (like Green Egg) table. I want to the Kamado Joe to sit on a concrete paver that will be on the lower shelf.

I can’t find a pre-made one to suit my liking and size so I’m going to pour my own. I would like the texture of the paver to look similar to a concrete foundation block. One in other words I don’t what large aggregate.

I made the form in the picture but not use what concrete mix to use.

-- Alaskan's for Global warming!


22 replies so far

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splintergroup

2730 posts in 1644 days


#1 posted 06-17-2019 04:08 PM

Of course you can tamp down the aggregate below the surface and use whatever texturing technique you have in mind. Given enough shaking/vibration/tapping/etc. the aggregate should also be sub-surface on the sides.

A more expensive solution is mix your own from a sack of cement and sand, no aggregate. Don’t forget that the less water you use the better, especially if you want a texture.

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Dark_Lightning

3471 posts in 3531 days


#2 posted 06-17-2019 04:09 PM

You can use mortar or even concrete mix with aggregate. Just trowel it smooth and work the mix so that a fair amount of water comes to the surface. That will settle the gravel below the surface, if you have gravel in the mixture. As that water evaporates, you can sponge the surface with the texture you like.

-- Random Orbital Nailer

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AlaskaGuy

5317 posts in 2731 days


#3 posted 06-17-2019 04:17 PM



Of course you can tamp down the aggregate below the surface and use whatever texturing technique you have in mind. Given enough shaking/vibration/tapping/etc. the aggregate should also be sub-surface on the sides.

A more expensive solution is mix your own from a sack of cement and sand, no aggregate. Don t forget that the less water you use the better, especially if you want a texture.

- splintergroup

Do you think plain mortar mix would work? think it wold be strong enough for intended purpose?


Of course you can tamp down the aggregate below the surface and use whatever texturing technique you have in mind. Given enough shaking/vibration/tapping/etc. the aggregate should also be sub-surface on the sides.

A more expensive solution is mix your own from a sack of cement and sand, no aggregate. Don t forget that the less water you use the better, especially if you want a texture.

- splintergroup


-- Alaskan's for Global warming!

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JayT

6228 posts in 2633 days


#4 posted 06-17-2019 04:21 PM

As they ^ said, troweling will bring more cement to the surface—you still run the risk of exposed large aggregate on the sides or bottom, though. Quikrete makes a Sand Mix that doesn’t have the large aggregate and might be more along the lines of what you are looking for.

-- https://www.jtplaneworks.com - In theory, there is no difference between theory and practice. In practice, there is.

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SMP

1199 posts in 328 days


#5 posted 06-17-2019 04:25 PM

If you want it lightweight with a cool texture, just mix cement, sand, and perlite, and use a brush/broom to brush the surface.

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Lazyman

3568 posts in 1809 days


#6 posted 06-17-2019 04:32 PM

Never done myself it but I have seen people (probably youtube?) mix cement, sand and perlite to make their own insulating concrete blocks. If I remember correctly, you mix the cement, add sand and then perlite, in that order, mixing each completely before adding the next one. The perlite sucks in some moisture from the mix, making it thicker and more moldable, so you just stop adding the perlite when you get the right consistency. The perlite will give it sort of a cinder block appearance, depending upon how much you add. I’ll see if I can find where I saw this if you cannot find it yourself.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

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ibewjon

685 posts in 3215 days


#7 posted 06-17-2019 04:37 PM

Be sure to put a piece of hardware cloth in it for reinforcement. 1/2” mesh will let the mix through, and even bend the wire up into the sides. With no large aggregate it would break easily without the mesh.

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AlaskaGuy

5317 posts in 2731 days


#8 posted 06-17-2019 05:19 PM

Thanks for all the replies. Let me throw in one more option/question. I have on hand a bad of quickrete fast setting mix on hand. If I could use this it would save me a 32 miles of driving. What is your thoughts on using this?

-- Alaskan's for Global warming!

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ibewjon

685 posts in 3215 days


#9 posted 06-17-2019 06:08 PM

Try it. What’s the loss other than a little time..

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SMP

1199 posts in 328 days


#10 posted 06-17-2019 06:21 PM



Thanks for all the replies. Let me throw in one more option/question. I have on hand a bad of quickrete fast setting mix on hand. If I could use this it would save me a 32 miles of driving. What is your thoughts on using this?

- AlaskaGuy

Well, if you already have that, just use it. Make sure to float the top a bit to get it smooth and get the big gravel down, and then you can use a brush to give it some texture. I have used a wallpaper brush to give it a nice rough brushed texture.

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AlaskaGuy

5317 posts in 2731 days


#11 posted 06-17-2019 07:15 PM


Thanks for all the replies. Let me throw in one more option/question. I have on hand a bad of quickrete fast setting mix on hand. If I could use this it would save me a 32 miles of driving. What is your thoughts on using this?

- AlaskaGuy

Well, if you already have that, just use it. Make sure to float the top a bit to get it smooth and get the big gravel down, and then you can use a brush to give it some texture. I have used a wallpaper brush to give it a nice rough brushed texture.

- SMP

Thanks for all the replies. Let me throw in one more option/question. I have on hand a bad of quickrete fast setting mix on hand. If I could use this it would save me a 32 miles of driving. What is your thoughts on using this?

- AlaskaGuy

Well, if you already have that, just use it. Make sure to float the top a bit to get it smooth and get the big gravel down, and then you can use a brush to give it some texture. I have used a wallpaper brush to give it a nice rough brushed texture.

- SMP


It’a done deal, I show results a bit later. I used what I had on hand

-- Alaskan's for Global warming!

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splintergroup

2730 posts in 1644 days


#12 posted 06-18-2019 06:37 PM

Don’t use the mortar mix (type S), probably too weak without a lot of added reinforcement.
Look forward to the results 8^)

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CaptainKlutz

1507 posts in 1916 days


#13 posted 06-18-2019 07:30 PM

FWIW:
When using concrete adjacent to high temperature devices like BBQ, outdoor oven, or smoker;
Be sure to seal all surfaces of the concrete with acrylic masonry sealer.
Why?
Concrete can and will absorb large amounts of water. If subject wet concrete to high temperatures, it can/will crack, shatter, and/or deconstruct (occasionally with explosive forces created by steam).

Learned this lesson hard way:
Had a concrete counter top in an outdoor kitchen explode, shattering a 12” wide section between a smoker and BBQ running side by side; just after a rain storm. Gravel shrapnel damaged a window 15 feet away, and golf ball size chunks traveled several feet. No one was nearby when it happened, fortunately.

Another recommendation by insurance agent investigating the incident was kitchen builder should have put fiberglass wool pads at edges of counter top molds where concrete counter top was less than 1” from natural gas cooking appliance shell. This insulates the concrete to help prevent moisture induced heating issues. Covering the exposed concrete with (sealed) decorative glazed tile will also reduce moisture intrusion issues.

PS – In wet unprotected environment, concrete next to heat sources needs to be re-sealed every couple years, sort of like a wood deck, or un-glazed tiles/tile grout in a shower.

PPS – Refractory brick is better choice for anything near/touching heating appliances as it doesn’t absorb water.

YMMV and Be safe, not sorry.

-- I'm an engineer not a woodworker, but I can randomly find useful tools and furniture inside a pile of lumber!

View AlaskaGuy's profile

AlaskaGuy

5317 posts in 2731 days


#14 posted 06-18-2019 08:06 PM

This picture show exactly what I’m doing. The kamado Joe with sit on the paver but there are little feet that hold it 1 inch off the concrete stone. So there is a 1 inch air space to help dissipate heat.

-- Alaskan's for Global warming!

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ibewjon

685 posts in 3215 days


#15 posted 06-18-2019 08:28 PM

The refractory brick I have seen easily absorbs water.

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