Foaming agent woes
@gemniii Did you get good foam and successful aircrete with your SLS? I bought some and our bubbles don't last longer than one hour... Would love any help from someone who has actually made aircrete. Thanks!
@abra Hello abra. The basic recipe for good aircrete gives details on foam weight. After asking specificly I feel comfortable in reply to your question.
The Recipe is very simple one 94lb bag type I/II portland cement. (TIP) many people are thrown off with this because it covers type 1 and 2 both. This is in fact type 2. It covers both 1 and two building aplications.
Pour 6 measured gallons of water into a suitable container. (We use a 50 gallon poly drum here. We mark the 6 gallon point to help speed the measuring process. We also have a mark at the 48 gallon point. This helps us to keep each batch uniform...
next we pour 5 gallons of water into a five gallon bucket and measure out One pint of Seventh Generation dish soap which we pour into the water. We then attach the little dragon to our compressor and turn it on. We capture the foam in a 1 quart container and weigh it on a scale. Adjusting the air flow from the compressor down from 90 P.S.I. until the foam weighs 3 ounces per quart. This generaly occurs at 80psi.
Next we pour the portland into the 6 gallons of water stiring until the mix is uniform and any clumps are no more.
We then turn on the littledragon and mix continualy until we reach 48 gallons. The foam is injected useing the mixer paddle. Once you reach 48 gallons you are ready to pour your finished product into your form.
In my experiance as long as you stick to the recipe you will have good results. You can find several recipe's in the Student Manual. I have not tried them all. I hope this helps and look forward to hearing how your progress developes.... Cheers
@brian-spooner Thank you for your well detailed response. We did everything you say here except that the air compressor was at 100psi but the little dragon was at 90psi. We dont see how this would make any difference... our foam weight was 3oz but the blocks of aircrete lost 2/3 their volume and the end result was crumbles you could break with hands.... So you have done this process and made good strong aircrete? Do you pour blocks or what?
@abra hello, the compressor is fine its the pressure at the little dragon that I reduce. yes I am currently makeing blocks for an upcoming build. I have made a couple vids one I just posted yesterday. The first pour I did produced blocks and I did not loose any volume. These were as you say not up to what I initialy expected. However in the second pour I misted the aircrete as it set quite often and covered it with a tarp. The result was good strong aircrete. We are now developeing a new form which kind of reminds me of those old metal ice trays. I think its also a good idea to take your time before breaking the block out of the form give it time to set up. you can view the vids here in the general discussion. As to the differance. there is definately something in making the weight of 3 oz per quart. but the only other thing I think is important is to work fast get it mixed and into the form dont let it sit if you can avoid it. Hope you have better results
Oh one other detail that I think is sometimes over looked dont forget to prime your pump. and keep in mind at the end uf your build you also apply a fabric reinforcement.
I bought some [SLS] and our bubbles don't last longer than one hour...
Bubbles lasting a whole hour is not bad. Seventh Generation foam rarely lasts that long sitting around in a bucket.
the end result was crumbles you could break with hands....
How long did you let the aircrete cure before breaking with your hands? Most aircrete crumbles in the hand for the first several days and sometimes even a couple weeks. The true strength of your aircrete can not be determined until one entire month has passed.
Abra, I'm sorry to hear that your aircrete lost 2/3 of its volume - that's not fun. It may take a few or several tries. I suggest practicing with smaller batches until you get the result you want. I say keep your foam density between 3 and 3.5 ounces per quart. I consider 3.25 ounces the best, with 3 and 3.5 on the extreme edges.
One of the biggest issues I am noticing with myself and others is foam density fluctuation. When you are making foam (while testing and while actually making aircrete) keep an eye on the air gauge of the Little Dragon to make sure it is correct and that is not moving. If your dial is bouncing around more than 5 psi then you may be creating foam that is poor quality. This is most likely due to sharing electricity with other applicances. Keep your Little Dragon on it's own cord, and try to plug it in to a circuit that is not running your mixer, or air compressor, or other major appliances.
@zander I would like to add that Zander is absolutely correct about utilizeing a dedicated power source. Good point Zander ;)
until the foam weighs 3 ounces per quart. This generaly occurs at 80psi.
The important PSI reading is taken while the system is in full operation. That operating pressure to achieve 3.0 to 3.5 ounces per quart could easily be as low as 40 or as high as 80 depending on so many variables such as type of foaming agent, temperature, elevation, electrical power source, last weeks astrological forecast, and current political climate.
@gemniii Dont buy the Sodium Sulfate! its just salt. Aircrete Harry had a mixup in that video that has caused a lot of confusion Im seeing (for myself included). What is talking about as a good foaming agent is Sodium Lauryl Sulfate (this is the product he has on the table to show) but the item he printed off Amazon is Sodium Sulfate, which is salt and makes no foam at all... You want SLS, it is more expensive but foams..
@joeboy You could try glycerine to make the bubbles last longer..
@zander Then Im totally confused why our aircrete lost 2/3 of its volume... We assumed it was because the bubbles popped... What else could it be? How long does it take for your aircrete to setup?
@abra Jee Wizz. Gosh golly! You should read the "THE WEAPONIZATION OF SOCIAL MEDIA" good book by the way. But when all else fails humor prevails. but I am thinking Zander summed it up. you might add in the astrological forecast but I have bad! bad! News, if you add politics I guarantee your bubbles will pop and everything that was whole in time shall crumble.
A long time ago on a far away planet I was an operator. As long as the switchboard was clearly labeled It was n'othing to put the right plug in the correct slot. Something tells me true that if you take a real moment and think. How long does it take for concrete to set up? I don't think you are truly that lost. what is it you have not tried...? To give the benefit of the doubt I should not probably answer for Zander. Stop adding stuff go back to the drawing board and follow the recipe! If you loose two thirds then use the cam and show us your progress that way we can work to figure out why you are loosing 2/3rd.
We assumed it was because the bubbles popped.
I think it would be correct to say that when aircrete loses volume it is caused by bubbles popping and the air escaping. What is more challenging is to say why the bubbles popped. I hear stories from very experienced aircrete makers about batches that collapse for reasons completely unknown to them. They thought they did everything like normal, but for some reason the bubbles collapsed. Then they simply try again and now it works. So it seems that there is some science to making aircrete, but there is also some art - some predictability, and some adventure. @Abra please take a look at my Aircrete Troubleshooting Guide to see if there is anything in there that might help you get the kind of results you are looking for.