Monday, January 17, 2011

The Stockpile Grows



This is about 200 blocks. You can sort of visualize the size a wall of 100 blocks might be. There are obviously some less than perfect ones in the pile but for the bodega they don't have to be pretty, just structurally sound. Any blocks that don't make the cut will get thrown out at build time.

Testing the Different Block Molds





We spent a full day testing the various molds I purchased with the machine. This was the first time for anything other than the lego mold. We also spent some time getting to know the machines fine tuning. We've been having problems with some of the soil sticking to the bottom mold along the edges. When you lift the block a chunk of it is still stuck to the mold and of course leaves a proportional sized chunk out of your block. Not cool...This only happens about 20% of the time and we didn't have the same problem with the first soil we used. We spent a fair amount of time on our first full production day tweaking the compression, the moisture of the mix and even varying the use of oil on the mold. We could never seem to eliminate the occasional stuck block. So, today we checked the plate risers for the bottom mold and also made sure all the screws for the molds were tight. We also took the opportunity to try out all of the molds. Here are a few of the things we learned;

  • There are 6 large bolts on the bottom press plate. At first I had no idea what they were for as they were not actually touching the lego bottom mold, screwed down to below flush. I realized what they do when we started testing the half block molds. There's a partition in the middle of the half block molds which needs to touch exactly with the top plate in the closed position. You can use the risers to adjust the height of the bottom mold plate in the box relative to the top. Once it's set just right then it 'cuts' the block for you. Too high and the top plate hits it (and could damage it), too low and the block doesn't get cut properly.
  • The lego half block mold had the same sticking problem as the full lego mold
  • The plain blocks came out perfect every time
  • Considering the time it takes to really get the machine set just right after changing the molds you don't want to do it too often. It doesn't take too long but will impact production so maybe once per day at most.
  • We think after further examination of the sticking problem that the new soil is a little too fine to work well with the lego mold. Rather than try to doctor the soil to be of use with the lego mold we're going to go full steam ahead with the plain blocks so we can get the bodega done.
  • The Roman arch mold works great. We'll definitely be making bunches of those.

Friday, January 14, 2011

Our First Drop Test



This is our first drop test. The block is a 10% cement mix using the soil from our second excavation site. As we're still pretty new at this we were pretty happy with the results. The block had only 1 1/2 weeks cure time so it was not even ready yet, but we wanted to know what it was really all about so we sacrificed one.

Our First Full Production Run





Today we did a full eight hours of nothing but making blocks with the screened soil from the previous week and a half. We're sticking with the 10% cement mix and trying to get enough blocks to build build the bodega as our production target. I can build it with as few as 500 but may go bigger depending on how many we come out with. The total made for the day was 135. We spent lots of time tweaking the compression on the press and the water mix trying to get it just right so we feel that once those things are worked out we should be able to get up to 300 a day. It's a good goal for now.

Big Pile of Screened Soil (yay!!!)



So, 5 guys screening for 8 days makes a pile of screened soil this big (the lighter colored soil on the right hand side). Just a guess but it looks like enough for about 800 blocks.

Our Second Excavation Site





And we like this new soil so much more...I'm proud that we have been able to make good blocks with the soil I had available at my site but we knew there had to be better soil in the area. One of the CEB books I've read suggested that to find the best soil you should talk to the traditional brick makers, as they would know. Lucky for me my neighbor is a brick maker. I'm going to go into a bit of detail here because this little story is integral to my aspirations for the project. I'm very wary of unintended consequences so as I move this project forward with the intention of creating some new entrepreneurial opportunities I didn't want to hurt existing markets (traditional bricks). To avoid this dilemma I decided to introduce the idea first to the brick makers as an addition to their business, not competition. Hopefully this will result in a significant net sum gain. So, all that being said I was really hoping to catch my neighbors interest in the project and let him come to his own terms as to how he might see himself fitting into it. This is a family actually. The father still makes bricks and his sons help and as these things go the sons are becoming progressively more in control of the daily processes as the business gets passed to the next generation. Both of his sons are helping with the CEB project with the eldest having worked his way purely by merit and enthusiasm into the supervisor position. Both of the sons have told me on numerous occasions that making CEBs is much easier than making bricks. So, in short, the Dad flat out said to us "you can never make blocks like this" before he saw the press. He changed his mind the first time I put one of the blocks in his hands. Little by little his interest increased and about a week and a half ago he offered to let me use some of the soil from his property as he thought it would be better to work with. Thankfully, he was right. The new site is only about 50 yards away but the difference in the effort required to screen the soil is like night and day. The quality of the blocks is much better as well. So, we got busy screening soil and kept going until we had a substantial pile ready to make blocks. You can see the first blocks we made with this new soil, 10% cement mix and a little more water than we used with the last soil. I intend to work out an arrangement with the Dad to use more soil and pay a certain price per block made. It needs to be priced like this so that a static price can be calculated for clients. I'll be documenting more of the business model soon as the details are starting to emerge.

Sunday, January 2, 2011

The First Practical Application


I wanted to grill out for New Year's Eve but didn't have a grill! Well, I had the grill grate but not the rest of it. I realized I could use some of my new blocks to make it happen and Bam!, chicken...It only took five minutes to assemble and I can move or reconfigure it as needed (no mortar). Myself and guests were all impressed at how well the blocks shielded the heat from the coals. The outside of the blocks at the hottest places were still completely cool to the touch. Actually cooler than the ambient air temp, amazing.

2 Weeks of Curing




The second round of testing has now been curing for about two weeks and everything seems to be going well. As you can see the blocks are still looking good and are starting to dry enough that the final natural color is starting to emerge.