Ok, I've had 7 requests this morning for the Jiffy Rock Method, so I'm just going to post it here.
Keep in mind that while it does work, and does produce rock that can be used in 9 days, the high heat involved might cause problems within the cement at any point. This is also a potential problem with the "Salt Rock" that the thread was started on - the risk potential is about equal for either type of rock. So far, my test pieces that have been in salt water for 6 months show no problems, but I feel it is important to provide a cautionary note - neither Jiffy nor Salt Rocks have been in use long enough to claim that they are completely 100% going to hold up for years and years to come. If you want more info on potential problems, try googling "chloride attack", a potential problem with the Salt Rocks. Most of which that is written pertains to the construction industry and how it effects reinforced steel, but it also messes with the cement itself, so look for that, also look for "Delayed Ettringite Formation", which is the main worry for the Jiffy Rock method
Anyway, I'm working on a refined method that will remove the high heat issue and would require an "Igloo" type cooler (or deep freezer) and a pressure cooker like is used for canning food. When that is ready to disclose, I will do so in full.
If you have any questions, please feel free to ask - I will try to answer to the best of my ability
Without any further ado...
Jiffy Rock Method For DIY Rock
I am not responsible for injuries or damages incurred by using this process! This is a DIY project, and could be dangerous if done stupidly!
Keep in mind that this has only been tested with the "Ol' Skool +" and Perlcrete type rock. I’ve made one test batch of the salt and sand only rock, and the salt is very difficult to release â€"œ try this method with salt and sand only rock only if you cast them really “fluffyâ€Â, with lots of holes.
Anyway.
Make a batch of rock - in damp sand for preference.
After 18-36 hours (the sooner, the better the results seem to be), carefully remove your rocks, brush them off and then get ready to bake them in a 450°F oven. They will still be punky, or sort of soft - that is exactly what we want - green rock.
To prep the oven, remove all fancy pans, etc. Cover racks with foil. Line bottom of oven with more foil. Fill a shallow metal cake pan (use an old (or cheap) pan) with hot water, and place as low as you can in the oven. I find that if I remove one rack completely, I can place the pan on the oven floor, place a rack above it and have lots of room for the rock.
Prep kitchen for acrid fumes. These fumes are not deadly, just fairly unpleasant. A fan venting in the window works great. Sheet over the kitchen door prevents most smell from migrating too much. Doing this at night keeps the heat down in the house.
Now place rocks inside - they can touch, or even be piled â€"œ just don’t touch the active heating element.
Turn oven on to 450°F. Bake for 4-6 hours. This needs to be a really moist heat, so halfway though, check the water level and add more hot water if needed.
Allow to cool for 1 hour, in the oven, with the door closed. While this is happening, prep water for salt release. The water needs to be hot. Hook a hose to your laundry hookup, boil it, or use your imagination - but the water needs to be hot.
Now, wearing gloves (I use chemical gloves) and eye protection, take the rock out of the oven (be careful, it will still be hot rock), and plunge it into your Hot release water. Plunge it in and out of the water several times to really get the water inside it. You may notice your water starting to simmer - this is great - it will help remove all the salt and crud quicker. Do all pieces, leave them in there and then allow water to cool. Drain. Again, using hot water, refill and allow to cool. Do this one more time.
If using a salt recipe, you will need to release the salt completely before moving on to the next step - this could take you a day or more to complete - figure 6-8 hours between refills, (heavy, dense pieces, or sand/salt only rocks will definitely take longer to be ready). Alternatively, you can just simmer the rock â€"œ it will require at least 12 hours this way, but finishes it quickly. Water will need to be changed in a simmer release, same as without simmering, but the time frame is greatly reduced. Simmer an hour or three, then change water.
When you think the salt is out, rinse the rock with clean water, pick-up a piece, allow the water to drain from it and catch the last drop or two from the bottom side on the tip of your finger â€"œ now taste it. Is it salty like chips? Or does it taste like mineral water?
After salt has been released, now we will soak in vinegar. I'm still working on ratios, so you can feel free to experiment at this stage. I'm going to recommend 1/2 gallon of vinegar to 4 gallons of water, which seems to work well. Look for the highest % you can on the vinegar - it comes in 4%-10% at the store. I'm looking into citric acid as well, so this step may change in the future. You just need enough liquid to cover the rocks and allow about 4" clearance over the top of the highest rock.
Allow rock to soak, for 3 days. Use a powerhead or pump to circulate the solution, if possible.
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At this point, the rock is as low as it will get with this method â€"œ all the rest of this follow stuff is testing. Make a note of how old your rock is at this point. Isn’t this cool? I’ve had rocks a month old that didn’t have a pH this low yet…
If you are not a Lab Monkey, Start a normal water kure now. Should take a week and a few water changes.
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Baking Tips and Observations
These are some tips and observations I've made over the last several bakes.
1. Use foil to cover the bottom of your stove as well as each rack you leave in. Efflorescence will be pulled out of the rock and form tiny puddles where your rock touches the foil. Your rock will be glued to the foil at these points, so when you pull it out, sand may go everywhere if you are not careful. Foil on the oven floor will prevent having to clean the stove so much afterward, and make the head of your kitchen happier with you.
2. Use a shallow metal cake/pie pan (or 2) in the oven to provide plenty of moisture. DO NOT USE GLASS OR PYREX! Half-way though the bake, check the pan to make sure it has water left in it. A dry bake will ruin the rock, moisture is the key.
3. Some stoves have a vent under one of the back burners. If you can, cover this vent with a metal cup or bit of foil. You may have to loosen/remove the burner to do this, but this will prevent the loss of too much moisture.
4. Turn off the houses' internal fans, etc. You want the fumes to remain confined to the kitchen. The fumes are nasty, mostly just the smell is bad, and not harmful as long as you don't go hang out in them. Use a fan in the kitchen window, and open the windows in other parts of the house to form a “draw thoughâ€Â. This will help with fumes.
5. When bake cycle is done, just turn off the stove and leave the rock lone for an hour. While the rock is hot, you will be in the greatest danger you will face - plunging your rocks. I think this exponentially speeds up salt release (if used), especially when really hot water is used and releases a lot of the crud. If the water you use is too cool, and the rocks too hot, they could explode, so be careful, and wear gloves and goggles for this step!
6. I will recommend to folks making the salt/cement or salt/cement/sand recipes to actually simmer the water they use for release, and if possible simmer the rocks themselves. I had a lot of trouble releasing the salt from these (though I don't make this recipe often, so that may be part of it), and if you are at the stove anyway, this will make it go faster. If you simmer the rocks, just make sure to use a pot that isn't going to be missed - you will more than likely not want to use it for food after this. Salvation Army or GoodWill might be places to find cheap stockpots for this.