Tag Archives: weight

Another day, another compression test

I  took the truck to Pearson Stone and we weighed the front axle weight.  6,800 pounds.  That means 3,400 pounds per front wheel weight.

I went to the shop and put the front of the truck up on wood blocks.  Then I jacked up one wheel and placed a ten pound plastic block under the wheel with a piece of steel on top of the block to eliminate the distortion caused by the tire patch only being on part of the block.

The block compressed about three quarters of an inch with the weight on it.  When I removed the weight the block returned to its original shape.

I repeated the experiment with a nine pound block.  The compression was about an inch and a half this time.

It will take some more tests by those a lot smarter than me to figure out the ideal weight of a block for making walls for a shelter.  As far as I am concerned that is just work that has to be done.  Engineers can figure out how much strength is required.  Then plastic blocks can be tested and we’ll have the information we need.

We did a compression test today

We don’t have access to an academics lab to do testing on the blocks.  So I did the next best thing…

Click on the “more” for photos and more dialog..

As you can see, the block was distorted in our redneck/red truck compression test.

This is a redneck’s red truck that weighs fifteen thousand pounds or so just about any day of the week empty.  Most of the weight is on the front axle when it’s empty, diesel motor and all.  I think an estimate of two ton or four thousand pounds or so would be a safe estimate of weight applied to the block.

One of the neat things about plastic is its resiliency.  If you look close I think you’ll agree that even if the block failed the two ton redneck red truck weight bearing test it will still work just fine in a wall.

We Made Our First Plastic Block Today

Of course the very first thing we did was test it for supporting weight.

It was quite a day.

Remember we started off with a trailer load of number three thru number seven plastic from the recycling center.  It turns out we had a lot of number one and it is more difficult to work with.  We discovered that number five was great.  We didn’thave any number six and seven, what we eventually want to use for the blocks.  Numbers one and two are valuable for recycling.  They give value to our blocks that isn’t desireable or necessary.  As it has been pointed out to me by others there are those out there that would love to find neatly bundled blocks worth thirty or so cents per lb at the street level recyclers.

We first tried to compress a block and then install the wire into the mold to secure the block.  That didn’t work.  Then we tried to install the wire without thinking it all through.  That worked better but it wasn’t any good. either.  The old adage about “learning more from our mistakes than our successes” is gospel when it comes to projects like this.

We learned a couple of  things with those mistakes.  We needed to add more plastic to the mold to make a more dense block.  We also made up the rod I designed for tightening the wire.  That and making the loops in the wire at the ram end of the mold enabled us to tighten the wire very tight easily.

The trick to tighteing the wire is a loop big enough for the tightening tool to pass through.  The trick to the tightening tools is the slot in the end of the tool.  Basically the way it works is the tool is slid through the loop to a point about four inches after the wire has been pulled hand tight.  The groove end is placed on the wire and then the loose end is folded over the handle of the tool.  The tool pulls the wire through the loop with a lot pressure when the tool is pushed over the loop.

It’s so simple.  Yet it’s so efficient.

The finished block is a nominal 8″ X 8″ X 16″.  I beat it with a hammer, bounced it around.  I like it.  Then we drove the pickup up on it to see how it handles weight.

I’ll be the first to admit that the block is one of those things where beauty can only be in the eye of the beholder.  For me it is beautiful.  That’s because I see a solution to two problems facing us today.  Plastic pollution is a worldwide issue.  Another world wide issue is affordable shelter.  This block addresses both of those issues, it takes trash plastic and makes it into an affordable alternative building material.

I have proven I believe that this block can be produced in the third world’s worst circumstances.

Now I want to take it further.

I want to see a manual model of this machine that is self contained and built for durability.  I want to see that machine manufactured and distributed everywhere alternative housing is needed.

I want to see another model of this machine that is automated for use in the industrialized world.

I would love to be part of all of the above and more.  But for me to do so is going to require financial assistance.  Any ideas for that kind of help is appreciated.