Second Round of Testing, Holding Steady

After three days of curing under plastic they seem to be holding up well. The first run that have been stored in the bodega are the best of all indicating how important it is to have them in a protected space for the first couple of weeks.

The Work Site

Here you can see the extraction pit on the far left, screening far right, mixing just to the left of the screening area and the press between the extraction pit and mixing area. The blocks were stored in the shade under plastic off to the left side.

Class is In!

Some shots from our Tuesday training session. The blocks laid out in a row make for a nice picture but they were quickly moved to a covered area.

Leftovers

This is soil that wouldn't easily go through the screen. Due to the high clay content where we're working it tends to clump no matter what you do. Still working on getting better with this part.

Screening and Mixing

Screening on the right, mixing area on the left.

Training Day 1, Afternoon Session

Looks like they're getting the hang of it!

Training Day 1, Morning Session

More video of Antonio showing how to use the press. This was in the morning when they first started checking it out. I'll upload a video of them using the machine in the afternoon to illustrate the training times involved.

Soil Mixing, Dry Components

Training session on how to mix the soil. This is showing the mixing of the cement with the screened soil. I have to apologize for the poor audio quality. We're on a tight budget and will be working to improve the production quality but I want to capture as much of the process as possible. Please note that we are still very new at this and these videos are intended to document our experiences not to provide an authoritative view.

A New Group Make Their First Block

This is from a training session where we're showing a group of new guys how the machine works. It's always great to see the expressions when the guys see a block come out of the press for the first time.

San Juan del Sur, Nicaragua (12/14/2010)

Screening Station

This is how we're screening the soil for now. This has emerged as the main bottleneck in the total process so we will hopefully be able to improve on how it's done as time goes on. We're using a pretty fine screen (about 1/4"). Our first day of testing involved the use of different screen sizes to see which made the best block and the smaller size seemed to be the best. It's more work but the quality of block is much better. We tried screening twice, first with a large screen then with the smaller one and decided that the extra effort wasn't worth it. So, we now are screening once with the small size.

Ideas That Didn't Work: Crushing the Soil Prior to Screening

We were hoping that if we dried the soil and used a plancheta (hand held crusher) that the result would be a finer soil that would go through the screen easier and allow us to use a greater percentage of the total extracted. The reality was that it took a long time to dry the soil completely and once you had that it was rock hard and still didn't break down too well even with the plancheta. If the soil was even slightly moist if would compact and create even more of a problem. We concluded that the time to spread the soil and wait for it to dry and then crush it was less efficient than taking it directly from the extraction pile to the screen.

This shows the soil prior to screening. Notice the large clumps...a real problem for the screening process. We're experimenting with different methods of breaking it down so that we get more out of the screening. One thing we tried that did not work was mixing the soil in a bucket with water and then letting it dry a few days. The resulting mix was so hard that it clearly wasn't what we were hoping for. From this station the soil goes to the screening, right now being carried in 5 gallon buckets. I bought a wheelbarrow yesterday but as yet the buckets have been preferable.

Our Second Extraction Pit

We started a new pit with the intention of digging the foundation for a future wall at the same time. We have the idea that if we're going to be making big holes to get the soil for blocks we may as well make the hole for the foundation and kill two birds with one stone. One difference between this pit and the first is we made the point of making it big enough that two guys can work at the same time without causing each other problems.

Block Dimensions

To illustrate the dimensions of the blocks. I didn't get a picture of the width measurement but it was 6".

The Model I Decided to Buy

This is the video that finally convinced me it was time to make the commitment to getting a CEB press. I had already decided to start with a manual press so the next question was to try and have one built or purchase one. After a few failed starts at building one I decided to just buy one and get going. This entire project has been done on a shoestring so it took a significant personal sacrifice to get the money together. As a result I was very keen to shop around. Having seen many different models of manual press before ever watching this video I was immediately aware of the features that indicated a great level of experience built into it. From start to finish GracoMaq was a pleasure to do business with and I would not hesitate to send business their way. They were very helpful in getting the order together and with the considerably obtuse task of shipping it to Nicaragua. They interfaced perfectly with my import agent here and kept me informed the whole time. Thanks to their entire team for building such a rock solid product.

Day 2, Make a Better Mix!

So we started our second day of testing with the intention of taking however long was needed to get a finer mix. We have a smaller screen (about 1/4") we used that produced a nice quality. We also used a fine screen (about 1/8") to filter the lime which resulted in a much better result without any clumps or rocks. Ideally I think you would want to use a flour sifter for this but that's a hard to find item here. We got the kind of mix we were hoping for but only with lots of effort due to the texture and humidity of the soil. It has a high clay content (about 30%) and retains moisture pretty much year round. Digging it up is hard work as it's nearly a block in it's natural state! It comes up in large clumps which have to be broken down, then screened. The screening process produces a lot of left over soil that has clumps too large to work with. We are already thinking about the best way to deal with that and think letting the soil dry for a day then using a manual crusher (plancheta) will be the fix we need. We did two batches, one with 10% lime and one with 10% cement. The block shown above was one of the cement stabilized blocks. I was hoping to take more pictures but my camera died. It's been on it's last leg for a while so I know I need to get a new one, especially now for this project. In the mean time, I will do the best I can to capture the process with what's available. My friend Paul has loaned me a nice lapel mic which I hope to use to put some videos together. We decided to wait until the block was done curing to clean the little bits from the edges as it would result in a cleaner look (we think).

The Official First Block

For better or worse, this is the very first block we made with the machine. We didn't expect perfection but we did take the time to try and make a good mix. Some obvious improvements we knew we had to make after looking at the results was to get a finer mix of both soil and lime with better distribution and we needed to get better compression. It's still holding together despite the flaws and we quickly set ourselves to making the needed adjustments. By the time we got our first blocks done the sunset was upon us so we all went home feeling very satisfied with little wheels turning in our heads over how we were going to improve on the next batch.

This batch used an 8% lime mix with our large screen (about 1/2").

My Early Christmas Present

It was always cool as a child to wake up on Christmas morning to find that shiny new bicycle waiting for you but I have to say this was even better. Silvio was happy to help me check it all out. Later on Pedro showed up and we all pitched in to get it assembled.

Up and Running!

After years of investigation into the Compressed Earth Block process and about a year and a half trying to get a press I am happy to report that we now have begun to make blocks. This initiative is part of a larger sustainable living project I have created called "SkyWurkz" which is meant to develop a new living model based on spontaneously ordered systems rather than the historic top down hierarchies. While this larger project is focused on the sustainable production of all the essentials for a fulfilling life (food, water, shelter, security, health, education) the CEB initiative is meant to fulfill the shelter requirement specifically and possibly a few other things as well. This is intended to provide both a literal and figurative base of operations towards the achievement of the other essentials. The SkyWurkz project is still very new and under development. Additional details will emerge as time goes on.

At this time I want to focus efforts towards mastering the CEB process and develop a small business model around this which can be replicated to create opportunities at the local level. My plan is to use a small piece of land I have near San Juan del Sur, Nicaragua to build first a small block factory then a home. This will hopefully be a good demonstration of the CEB process (and also architecture and construction with CEB) that I will then use to build a new market awareness. Once the idea starts to take root I hope to position the local workers who I will be training to take advantage of the new opportunity as well.

There has already been interest expressed from various parties on the potential use of CEB for their projects so I will be working hard to get the tests done so we can show a solid proof of concept. I will of course try to capture as much of the process as I can and intend to "open source" everything both regarding the actual making of blocks and my experiences with the business model. The entire plan is quite involved and still very much a work in progress so I will elaborate more on that as time goes on. For now, let's get this blog started with a few posts bringing us up to date and then a bit about where I intend to go from here.

Thanks for your interest in the project!