Backyard Shed: Part 1

My workshop has recently grown to include a small amount of metalworking equipment - specifically an oxy/acetylene welding setup.  The shop was already bursting at the seams since it stores all my woodworking equipment, as well as a car and a motorcycle.  On top of that, all the yard tools are stored in there as well, including a pushmower, a tiller, a wheelbarrow, and a dozen handled tools like shovels, rakes, and hoes.  All this in a pretty typically sized 2 car garage meant that even adding any big tools just wasn't possible.

I have been wanting to build a shed in the backyard for some time to store lawn tools.  This would get them out of the workshop and free up some space.  Like most folks, I have a long list of projects, though, and this one has been put off time and time again.  But, in light of the newly exacerbated overcrowding, I decided to make the shed bigger to allow for a metalworking area.

My backyard is a good size, but we already have some dedicated garden space back there that left me with really only one viable location for the building, a space along a fence in between the fence and a tree.  This tree limits one dimension of the building to only 5 feet.  The only thing I could do to increase the size was to lengthen the building along the fence.  So I picked a length of 16 feet.  This was about as long as the space in the yard would allow, and I think it will give me enough space to store the things I have in mind.

I started with a sketchup model that included a representation of the fence and the tree.

The design of the building is basically a pole barn, but I knew from when I built my fence that there were too many buried wires in that area of the yard for me to bury the posts like one usually would for this type of building.  So, that led me to my first design challenge - how to build this type of building without setting posts in the ground.

There are probably many ways one could do it.  I knew I didn't want to pour a concrete slab, which would probably be a typical way to solve this problem; that would add too much expense and complexity to the project.  I considered using the concrete deck blocks they sell at every home center - here is an example.  These honestly would have worked fine, I'm sure, but I wanted a more customized solution.

I decided to cast my own concrete blocks that would have a socket for the post, similar to the commercially available ones, but without the four notches opening the socket to the outside.  I also wanted a way to attach my blocks to my posts, to provide a little extra security.  To that end, I wanted to cast a block with a hole going right through the socket and the sides of the block through which a pin could be inserted, tying the block to the post.

I wanted two different block designs, one for the posts in the front of the shed, and a different one for the posts in the back of the shed.  The posts for the back of the shed would have the socket for the post in the middle side-to-side, but adjacent to the back of the block to allow the post to sit right up against the fence.  I started my block making crusade on these back posts.

I started with some low grade 1x12 boards that Lowes sells as "shelf boards."  I cut them down to size...

Then drilled holes

And screwed them together

Then I started working on the part of the mold that would cast the hole for the rod.  These two molds were intended to make both the front-of-the-shed and back-of-the-shed style blocks, and I made the setup for the front blocks first.  You can see the dowel is centered for the front block design in this picture.

Then I cut a couple of 6 inch blocks and bored 5/8" holes to match those in the side.

Here is the mold assembled for a front block setup.

As an afterthought,  I stuck on a couple of shims to ensure the cast-in hole was a bit bigger than the post so the fit isn't too tight.

Here are the two molds with the post stumps in the position for casting the back-of-the-shed style blocks.  (They're sitting upside down in this picture)

I also put a U-shaped piece of concrete reinforcing mesh in these to strengthen them.

I mixed up some bagged quikrete in a wheelbarrow.

And put it into the two molds to cast the first two blocks.

And here's what block number one looked like when it came out.

And block number 2.  The wooden dowel I used to cast the hole for the rod absorbed a lot of water during the casting and stuck and eventually broke off.  I ended up breaking the corners off this block while trying to drill and hammer the remaining dowel out.

For my next round of casting, I switched to 5/8" metal rod.  Here are the second 2 back posts in the mold.

This is how I removed the stumps for the back post design.  They stick somewhat to the concrete, but since they are open on one side you can just hammer them towards the open side.

I made a second mold that is two blocks side by side.  It is set up for the front block design with the rod in the center in this picture.

The post stumps in the front block design are completely surrounded by concrete, and I pretty quickly realized I was in a mess.  I really didn't make good provisions for getting these stumps out, so I ended up going through a pretty miserable process of drilling and chiseling them out. 

I made this curved chisel in my forge out of a piece of cultivator spring I scavenged to help with digging this stump out.  Oh yeah - I have a forge now if you didn't know.  A big thank you to Justin of JBs Forge for getting me into the hobby of blacksmithing!

 

Here is one of the blocks after the stump removal.  You can see burn marks from where I got desperate and tried to burn the stump out with a torch.  That did not work at all.

After the absolute drudgery of drilling and chiseling out the two stumps from the first two front blocks, I decided to try something else.  I made a wooden box the size of the post stump out of 1/4" plywood and some spruce scraps.

I stuck this on a little metal base I made by tack welding a piece of 5/8" rod to a piece of metal plate the size of the bottom of the wooden box with construction adhesive.   The idea of the piece of rod is that it allows you to drive the whole thing out from the bottom of the block once it is cured, and doubles as a drainage hole in the finished product.

Here is the assembly with the holes drilled ready to go.

I also made a similar box out of some scrap metal just tack welded together.

For the last two blocks, I rigged up the double mold again to try the two different box assemblies side by side.  Here they are ready to go with the reinforcing mesh already in place.

Finally, I mixed up the last of the concrete and cast the last two blocks.

Once they are done, I drive out the wooden box from the bottom.  You can see it coming out from the top as I drive from the bottom of the block.

It came out fairly cleanly and quickly, although you can see it did break out a small area around the top of the hole.

You can see the metal bottom bent on the way out.  I guess it caught in the concrete somewhere along the way.

Next I drove out the metal one.  It was much, much harder to get out.  I pretty quickly broke the corners of the box loose at the top hoping this would help.  In truth, it didn't.

I expected the metal box to work better than the wooden one, based on my experience with metal rod vs dowel for casting the hole.  I can only guess that maybe the box was slightly tapered, with the bottom of the box slightly larger than the top.  That would explain why it was so difficult to get out.  My tools and skills for working metal are much less accurate than they are for woodworking, so perhaps my wooden box was just much more square and straight.

Since the last two front blocks I made had a drainage hole formed by the stub of rod I used to drive out the boxes, I drilled drainage holes in the other two front blocks.  I guess concrete bits aren't really meant to drill through holes.  The tip of the little cutter at the end of the bit broke right as it exited the other side of the hole.  I broke one bit per hole, but it's fair to point out these were cheap bits that probably came in some cheap combo set.

Casting these blocks was really a long, arduous process.  I took me two weeks, working nights and weekends on it.  If I was faced with this same dilemma of wanting to build a pole style building but not being able to dig holes for the posts again, I think I would form and cast the blocks in place with the posts already in them.  I would dig my spot flat, then put a paver in, then place the form on top and the post inside the form.  Then I'd rig supports to hold the post level, and pour in my concrete.  I think this would be simpler and give you better results, and with the benefit of hindsight, I don't know why I didn't think to do it this way to start with.  But regardless, I learned a lot along the way and in the end I did successfully produce blocks I could use.

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