Home brew concrete and cast-in-place concrete.

[stonecutter]

Re: Home brew concrete and cast-in-place concrete.

But he is a slacker when it comes to building his oven.

Ouch..the truth hurts. I do have some legit reasons about the delay...one being some serious health issues that my wife has been having the last few months. Another is that this base is unconventional, at least I think it is...I have never seen another like it. Plus, I tore the stonework down twice...yeah I know. Not excuses here, just sayin!

Hopefully I can keep moving forward from here and post pizza pictures instead of construction. Thanks for the compliments BTW, much appreciated.

[mikku]

Re: Home brew concrete and cast-in-place concrete.

As for the first thing--I thought that is what I just said!

As for the second part, I don't know? --have not even gotten my toes wet on this forum, but got close to burning my fingers a little while back. Now trying to tread more lightly without making too many waves. Seems like there is a "wolf pack" behind the scenes---have to wait to see who holds the spot of "alpha male?" "Leader of the pack" v rooooooooooommmmm!

Keep the ideas coming in!

This forum is addicting as pointed out by others, I think I'll go back to some "Korean white liquor and lime (Shochu-lime-hi) for a while" and see where these threads go on their own!"

[Tscarborough]

Re: Home brew concrete and cast-in-place concrete.

But he is a slacker when it comes to building his oven.

[Tscarborough]

Re: Home brew concrete and cast-in-place concrete.

Stonecutter is a Master Craftsman, an artist in stone as well.

[mikku]

Re: Home brew concrete and cast-in-place concrete.

I am really happy to read what you say!

A lot of us "old farts" after doing something the same for a long time, are resistant to change. Similarly, we like to argue or look at everything in a negative way--fast to point out faults, slow on giving useful advice or praise!

Another old saying "Jack of all trades, master of none" is a description of me.
The "Jack", description (tries everything but never really getting good at anything). You seem more like the "Master tradesman", (testing new things-but only incorporating them into a build if they "pass your threshold of performance".)

I am glad to make your acquaintance!

On a different note: I see by some previous threads that the topic of "render recipe's" has been massaged to death...just takes some searching to find answers right beneath my nose!

[stonecutter]

Re: Home brew concrete and cast-in-place concrete.

You seem very conservative based on your comments of cements etc, but much more open to the use of this "media" to communicate. The same media that you use to show your great skills and accomplishments. With that in mind, I would assume that you would seek out materials that would improve and protect your builds so that future generations "Possibly, hundreds of years from now could reflect back and appreciate your efforts today"!

By my own admission I am conservative when using CHEMICAL ADDITIVES to mortar and concrete, but not in any approach that has anything to do with building...my latest oven is a good example of what I am talking about. I do mostly custom work, and with most of that work, I rarely do the same thing twice, which allows me to constantly try new methods and techniques..and yes, I always try to use quality material that will add to the longevity of whatever is built.
My reservations with products like Xypex are this...whenever masonry is made to be "waterproof" you will now have other issues to think about. Mortar or concrete absorb moisture yes, but it also releases it. When this process is hampered by something added to it which is meant to keep water out of the material itself, the damage is greatly exhilarated than normal. An example of this is when portland based mortar is used over a lime mortar in restoration work...the cement mortar traps moisture behind it and it destroys the work because the masonry can't breath anymore. Modern concrete uses portland cement and by nature it doesn't breath very well, thus the need to "waterproof" it in certain applications, because it readily absorbs moisture.

I don't know enough about Xypex to say if it is a good product...but I do know about issues that come up when you don't find ways to work with nature and instead try to hold it back or radically alter something that has been used for centuries...that is where my view point is coming from. I'm not saying that I'm right and using chemicals is wrong either, just that this is my approach with products like this.
Everything breaks down overtime too, so the question for me would be, how does the chemical being used affect the product in a relatively short time? Because, lets be honest...I am not under the delusion that my work will be around for centuries...too many variables there. Realistically, the best quality mortar or concrete out there will develop some sort of maintenance issue within 20 - 50 years. I guess if you have a waterproofing chemical that doesn't cause rapid decomposition of your masonry work within that time frame, IMO, that is a pretty good product.

All that said, I admit that my knowledge has more to do with with stonemasonry, not concrete...I have only started learning about concrete for only about the last 8 years or so.

[mikku]

Re: Home brew concrete and cast-in-place concrete.

Stonecutter- thanks for checking in..
I am really new to this forum--only one month as of today! But so far, there have been a lot of really talented persons who have checked out what I have said and truely built on those ideas. All have given me clarity to what I am attempting to do. I have learned alot over this short time.

You seem to have a wealth of experience in what you do--great photos on your homepage and your work is superior.

You seem very conservative based on your comments of cements etc, but much more open to the use of this "media" to communicate. The same media that you use to show your great skills and accomplishments. With that in mind, I would assume that you would seek out materials that would improve and protect your builds so that future generations "Possibly, hundreds of years from now could reflect back and appreciate your efforts today"!

Welcome back! class of 2007! Your words of experience are greatly welcome!

The castable refractory that I am using is new compared to brick--if my oven lasts 5, 20, or more years...which part will remain? Firebrick? Cast dome? maybe parts of the base...not the steel though? But it will have had utility for the life of it's builder. Longer than that is a lot to expect from any material!

Water can be the builder's biggest enemy...as you well know, a few drops of it in a crack on a stone when frozen can split the largest boulder eventually turning it to sand--then dust!

[stonecutter]

Re: Home brew concrete and cast-in-place concrete.

I "Googled" (Xypex) and came across a report on a project "Tsuen Wan Station Project" --an evaluation of this product.
It is really an amazing product from what I briefly read. Forms a crystaline structure that fills voids in concrete to prevent water penetration.. And the crystaline structure continues to grow with age. Properties that remain equalling the service life of the concrete. That is my short version of a 17 page report.

Also, it stated that it could be applied to the outside of a surface- presumably as a liquid form (or) in some type of mortar to give waterproofing qualities. But a better scenerio would be to use it when the concrete is being mixed--instead of a surface treatment- the entire casting would be waterproofed!

Simply amazing.

I would assume that this product would be popular and available here. It would be used in highway and rail (tunnel) construction where water is an issue causing degradation of reinforcement etc. Japan has a huge infrastructure of tunnels in its transportation network, both above and below sea level! I guess searching for it might not be so difficult--That is "if you know the right question to ask"...(Abreviated "Laurentius quote")

Another great piece of information to file in the back of your mind. If a situation arises where you are building an oven or (in fact anything) from concrete- that is subject to running water, or contact with high concentrations of water--that could be problematic...there is a product available to solve the problem--and a name for it!

That product was discussed a little on another forum I belong to. The thing about that product is that it is relatively new, and hasn't really been around long enough to see if there are issues that develop later. I am specifically thinking about the additives....but I am pretty conservative when it comes to adding things to mortar or concrete other than what has been around for centuries. Maybe my reservations about Xypex are unfounded and it may do as promised, but when something seems to be too good to be true, it usually is.

[Gulf]

Re: Home brew concrete and cast-in-place concrete.

Don't use chunk charcoal, that which you described in option 1. It burns way to hot for the initial curing.
I don't know anything about bio-fuels.

Thanks for the clarification.
Charcoal type fuels available here are basically two types.

1) Those that come in boxes and appear to be short chunks of wood that have been heated to some high temp w/o oxygen in the manufacture process.

2) A bio-fuel type of charcoal that looks like a thick button- about 4" in diameter, 2" thick with some holes in it. Must be made in some high pressure extrusion process.

These are the standards- Briquettes or heat beads can be found but not every "home center or hardware store" carries them. Takes a little more searching and "asking the right questions"!

Lots of things to mull over... Outdoor- Daytime and night temperatures are below freezing but not every day. It would take a lot of attention to maintain a temperature above the boiling point for water for an extended period of time!

Right now, the dome is quite cool to the touch.. even though the ambient temperature is steady. Must be drying nicely--cooling sensation the result of evaporation..

I have considered just using a fan to move the air, but for now...things are on hold until I can determine if an initial set--water retention is required. The dome is draped in plastic.

[mikku]

Re: Home brew concrete and cast-in-place concrete.

Thanks for the clarification.
Charcoal type fuels available here are basically two types.

1) Those that come in boxes and appear to be short chunks of wood that have been heated to some high temp w/o oxygen in the manufacture process.

2) A bio-fuel type of charcoal that looks like a thick button- about 4" in diameter, 2" thick with some holes in it. Must be made in some high pressure extrusion process.

These are the standards- Briquettes or heat beads can be found but not every "home center or hardware store" carries them. Takes a little more searching and "asking the right questions"!

Lots of things to mull over... Outdoor- Daytime and night temperatures are below freezing but not every day. It would take a lot of attention to maintain a temperature above the boiling point for water for an extended period of time!

Right now, the dome is quite cool to the touch.. even though the ambient temperature is steady. Must be drying nicely--cooling sensation the result of evaporation..

I have considered just using a fan to move the air, but for now...things are on hold until I can determine if an initial set--water retention is required. The dome is draped in plastic.

[Gulf]

Re: Home brew concrete and cast-in-place concrete.

Mikku,
Yes, heat beads are charcoal briquettes in the U.S. We just use the "heat beads" term on this forum to pay homage to the Master . That is what Karangi Dude calls them. I believe that heat bead is an Australian term.

David S. is "golden" for reminding everyone to dry the V/Pcrete layer before rendering. I listened to, and followed his advice.

As for as the KD "heat beads " (charcoal briquettes) Cure: Make sure that you use the lighting technique KD used. The charcoal chimneys are kindled with paper, not starter fluid, which as you probably know will add bad flavor to metal grills. There is no telling how long it would take to get that stink out of porous firebrick .

One curing method is to start with smaller, increasing to larger, wood fires to cure the dome. No matter how small of a wood fire is started in a WFO, there is a direct flame impingement on at least the apex of the dome. This is uneven heating on uncured masonry.

This may be just my opinion but, I gathered from Doug's technique that, you want to heat the dome as evenly as possible to just a little above the boiling point of water. And keep it there until the outside of the insulated dome is no longer warm to the touch. Once the water has been driven out, the outside of the insulation layer should be almost to ambient temperature. The briquettes offer a milder way of slowly bringing the dome to this stage.

Now is the time to start a small wood fire in the oven and keep adding wood until that dome clears .

[mikku]

Re: Home brew concrete and cast-in-place concrete.

I hope for additional input from more (pro's in this forum), would also like to expand the thread to include a recipe for render.

This is something I need to tackle very soon! Some info would be greatly appreciated! Or has this been covered somewhere before???

[mikku]

Re: Home brew concrete and cast-in-place concrete.

I "Googled" (Xypex) and came across a report on a project "Tsuen Wan Station Project" --an evaluation of this product.
It is really an amazing product from what I briefly read. Forms a crystaline structure that fills voids in concrete to prevent water penetration.. And the crystaline structure continues to grow with age. Properties that remain equalling the service life of the concrete. That is my short version of a 17 page report.

Also, it stated that it could be applied to the outside of a surface- presumably as a liquid form (or) in some type of mortar to give waterproofing qualities. But a better scenerio would be to use it when the concrete is being mixed--instead of a surface treatment- the entire casting would be waterproofed!

Simply amazing.

I would assume that this product would be popular and available here. It would be used in highway and rail (tunnel) construction where water is an issue causing degradation of reinforcement etc. Japan has a huge infrastructure of tunnels in its transportation network, both above and below sea level! I guess searching for it might not be so difficult--That is "if you know the right question to ask"...(Abreviated "Laurentius quote")

Another great piece of information to file in the back of your mind. If a situation arises where you are building an oven or (in fact anything) from concrete- that is subject to running water, or contact with high concentrations of water--that could be problematic...there is a product available to solve the problem--and a name for it!

[david s]

Re: Home brew concrete and cast-in-place concrete.

David S- Hello!
What material would you use as an admixture to do that?

The stuff I use is called Xypex C 1000 NF, it does a number of things, one of them being to make the concrete waterproof. This brand may not be available to you, but something similar should be. It is expensive.

[mikku]

Re: Home brew concrete and cast-in-place concrete.

Gulf- Hello!
David S warned me about getting the water out as well! I finished the main insulation this afternoon (other thread) and was B.S. ing with an electrician friend--telling him all about WFO's and did a quick calculation. Yesterday and today- I plastered on about 80 liters of water in this pericrete mix. That is over 20 gallons of water! Wow!!!! I even wet the dome so that the water would not immediately suck out of the mix...where the water hit yesterdays' work--zap and it was gone!

Tomorrow, I have to put the heavy wheels on and roll the entire thing next to the garage door, some sun and wind. With a chimney in place and the rest of the insulation in place --by next week, I was thinking about some kind of an initial dry-out. I saw the "Kanagi Dude- Heat Bead Cure" thread, and for the life of me could not figure out what a heat bead might be. After looking at the photos--what it looked like are "charcoal briquettes"--Is that an area name for the same thing?

What is the "real poop" on them? Too hot they burn up firebrick or refractory or what?

I did not read your entire thread--I will have to and pick up the tips mixed up in the text.

(Other note): The formwork just takes a little time, playing around with a compound slide miter box. Once the angles are set- the ring cuts are the same, inner form and outer form. Just the length of the leg changes. It can be laid out with a template on plywood, by simply dividing to make a 16 side figure. No magic.

Really I was just playing with the form and once it was completed, thought it was a waste of time not to fill it with refractory..That is when this all got started!

A very-very long time ago, I did some refractory work at a site that processes taconite ore into pellets. Their kilns are huge! I worked many weeks on making a form for the "dam" inside one of these kilns--at that time, it was the first time an APGreen contractor ever poured this section in one piece. There were probably thousands of bags that went into this single casting. On top of that, the form had to be made then disassembled to a size that would fit into the kiln opening door! As a "refractory carpenter", I got an "adda boy" thumbs up when the form held and a reminder to get back to work on a special form for a recuperation duct. Funny how some work experience gives a little confidence to try a new hobby.