Concrete Work - Part 3

The "concrete work" is the making of the footings, the 8" thick stem walls, garage slab, and driveway section associated with my project to extend the garage six feet.  It also includes the slab for the new front porch.  Once the concrete work is done, it's going to sit there waiting for the construction of the garage extension and the front porch roof, which may or may not happen next spring (or who knows when) — but the concrete will be ready!

So the construction of the wooden forms for the concrete went relatively quickly, if not straightforward.  In my past, I've put forms together using special metal rods called "snap ties," which hold the two sides of the forms together at a constant separation, and resist the force of the wet concrete, which tries to push the form walls out (with considerable force).  Snap ties look like this:

Neither Home Depot nor Lowe's carried them, and an internet search turned up no local sources.  I did find out later, however, that a couple of concrete supply companies in the county have them (they apparently just don't have web sites with sophisticated search engines key words).  So I improvised.

The lower trench I dug served as the form for the footings, and I built wooden forms that sat on a wider higher trench for the 24" high stem walls.  Looked like this:

The lower section in the front wall is for the entrance to the garage, that is, where the garage door will go.  To keep the wet concrete from the higher section of the wall flowing out the lower opening, I screwed a section of plywood on top of the opening after the lower section was filled with concrete and leveled.  Here it is, ready to go.

The new walls are tied into the old garage concrete with sections of rebar epoxied into holes drilled into the existing concrete.  I did the same thing with the porch slab. 

The existing garage was built on a slab with no stem wall and no real footings, just a 6" wide by 6" high "curb" on top of the outside edge of the slab.  So there was not much to tie into.

I put half-inch rebar in the forms — two rods running parallel inside the footings, and through the stem wall—one half-way up and two near the top.  The anchor bolts for the bottom plate of the future stud wall were put in place in wooden braces that held the tops of the forms 8" apart:

You can see that I suspended the upper rebar from the wooden braces using nylon string.  That worked, although if I had located the snap ties, I would have wired the rebar to the snap ties for a more solid connection.  File that under — "if I had it to do over again."

The porch slab forms were more straightforward, and much quicker.  They were just three 2x6s held in place with screws and steel stakes.

The future porch roof will be supported by two 4x6" posts at the front corners.  The metal brackets that connect the posts to the slab are anchored by bolts cast into the concrete, and sitting on top of footings reinforced with steel rebar:

I hired a neighbor (who happens to be a concrete maestro) to take charge of the actual concrete pour.  He brought along his son-in-law.  And there was the concrete truck driver, and also the guy with the concrete pumper (concrete run through a big hose that could be more accurately placed inside the 8" wide forms, and could run over to the front porch — otherwise it would be pushing wheelbarrows back and forth).  A big party.  When wet concrete starts flowing, things happen quickly, and the more people on hand, the better.  And that's a fact!

We filled up the footings first, and to give that concrete time to start to firm up (so pressure from concrete above would not force it out around the bottom of the forms), we moved over to the porch.

At that point, things became too hectic for me to take any more photos.  I had calculated that we would need 3.35 cubic yards of concrete, and planned to add another 10% margin, which took the total to about 3.7 cubic yards.  But you can only order concrete in half-yard increments, so we ordered 3.5 cubic yards, and that turned out to be not quite enough.  I ended up hand-mixing three 60-pound bags of concrete to top off the forms.  Another lesson for the "if I had it to do over again" file.  But if everything was not optimal, the job got done, and no disasters.

That was Saturday morning.  I started taking apart the form supports late Sunday, and removed the forms today (Monday).

And the porch:

So the next step is to backfill on both sides of the stem wall, to bring the level of the soil about 4" below the level of the new garage slab extension, and the new driveway directly in front of the extended garage.  And then wire mesh and rebar for the new slab section.  And then more concrete (in about two weeks).

And also back to the kitchen countertop project.  I'll be buying more wood for that tomorrow.

Concrete work & kitchen countertop — Part 2

The work on the concrete foundations for the future garage extension, and on the laminated kitchen countertop have been going on concurrently, so this post updates those two projects.  The weather has gotten even hotter here lately — every summer hotter than the last — and now we're in a string of days with highs around 100˚.  So happy I got the new heating/cooling system in last winter!  A/C works great!  But these two projects are outdoors (or in the garage) :-(  So work some, go in to cool down, repeat.

While the digging was going on, I gravitated toward the much more pleasant countertop lamination.  In the last post, I described the building of the flat and level glue-up frame.  When that was done, I used the table saw to make strips out of 3/4" thick maple, cherry, and walnut boards, a little over one inch wide.  These were turned on edge and arranged on my gluing frame. 

Initially, I planned to do the whole countertop in maple, with just two walnut stripes.  But then cherry came in, and I ended up with more strips of both walnut and cherry, so I just started arranging them until I ended up with something I thought I would not tire of over a decade or two. 

I put the plywood undermount sink template (that I had made some time ago) on top of the strips so I could see where I didn't need wood, since the opening would be cut away when the countertop was all laminated.  I am laminating the rough countertop to be thirteen feet long; the ends will be cut off square to a finished length of 12.5 feet.  Ideally, I would have thirteen-foot long boards, but most of my strips are at most ten feet long, so by cutting them to skip the holes for the sink and the cooktop cutouts, one ten-foot board could span the whole thirteen-foot long countertop blank.  (The pictures may explain that better.)

I am using a West System marine epoxy to laminate all the strips together, and will also put a couple of coats of epoxy on the finished countertop for complete waterproofing and stability.  I'm using biscuits to align the strips during the gluing process (inserted into matching slots in adjacent strips).  The working time for the two-part epoxy I was using is about 25 minutes.  I set a kitchen timer so I would know when I had to start clamping the strips together (lest the epoxy start to set up, and everything thrown away).  I managed to glue five strips together for the first batch, using twelve clamps.

For that first batch, I brushed the epoxy on each strip individually, and then mated it to the next strip, and so on.  For the second batch, I arranged the strips against each other so I could brush the epoxy on a number of strips at the same time.  Much faster. 

Once the strips are glued together, they have to be planed flat and smooth, because of the glue runout and, well, because the strips are never going to be perfectly aligned.  The kitchen countertop is 30" deep, while my thickness planer has a 12" width capacity.  So I'm laminating the countertop in three sections, each between ten and eleven inches wide.  Each section goes through the planer separately.  Then the three sections will be carefully aligned and glued together.  When the strips are clamped together, the epoxy gets squeezed out the top, but mostly out the bottom.  I can scrape off the excess glue from the top before it hardens, but not from the bottom, so the first passes through the planer need to take the glue off the bottom.

Lots of space needed to get the long countertop section through the planer:

The second section is done pretty much the same as the first section, although the strips for the second section have to be clamped to the first section (but not glued yet), so the second section will be a perfect match to the first section.  There are slight variations in the thickness of the strips which means that even if the first strip was perfectly straight, the last strip in a section will not be.  Once the strips are glued together to form a 10" wide section, no amount of clamping will bend them to conform to the adjacent section, unless they were clamped together during the gluing process.

For the first section, I could use my six 12" clamps and my six 24" clamps.  For the second 10" section, clamped to the first section, the 12" clamps would not work.  So out came my 48" clamps to supplement my 24" clamps.  Can't do a project like this without a lot of clamps.

Here's a look at the first two sections sitting side-by-side, after preliminary planing (all three sections will get a final fine planing to bring them to the same thickness before being glued together).  The overall view, showing the cooktop cutout and the more distant sink cutout:

And a closer view.  When coated with epoxy, the colors will be darker and more saturated, and the plan is to sand the epoxy to a satin finish.

As for the third section, I need to make the hour drive down to the hardwood store to buy more wood before countertop work resumes.  Work has shifted to the concrete.

I finally finished digging the trench into the rock-hard ground.  Again, the deeper trench is for the footings, and the forms for the 24" stem wall will sit, more or less, on the outer shallower trench.

The trenchworks had to be fairly precisely located, straight, square, and at the proper depth.  To ensure the right depth for upper and lower trenches, I used a small laser level, along with a stick marked with the various depths.  The laser level sat on the garage floor on a purpose-built box as a reference height.

And then I started building the stem wall forms, in sections, attaching them together, positioning, adjusting elevation, etc.  At this point all the outer wall sections are in place.  Now I need to start putting the rebar in, and then build and install the inner sections of the forms.  Then tie them together, shim them level, stake them in place.  Then concrete!

Update . . .

Work on the new concrete foundation for the garage extension has been slow, so I'm doing an update, rather than wait for what could be months (or years) until the project is done.  First, it took some time to get a company here to remove the part of the old concrete driveway directly in front of the garage.  Second, the ground underneath was something like asphalt in hardness, so digging has been slow (and in discovering a way to blast through it, I did a bad thing to my usually robust lower back — which halted digging for almost a week).  And third, it's been hot here, and unusually humid, so I've limited my daily excavating work.

Here's how the concrete removal went.  First, sawing up the concrete with a big diamond saw:

And then, breaking up the concrete with a monster jack hammer mounted on a Bobcat:

Which produced a lot of rubble that was loaded into a big dump truck:

And by lunchtime, it was all gone!

I then mounted a big tarp over the work area to provide some shade for my digs:

Meanwhile, I designed the foundation, the stud wall that will go on top (details of which were needed to locate the anchor bolts in the foundation wall), then I designed the forms to be used to pour the concrete.  The footings, foundation wall, and form design dictated the depth and size of the trench required.  I bought a laser level to make sure the depth was accurate all around the future wall, and then after laying out the dimensions on the ground with string, proceeded to dig (or tried to dig).

I started with a mattock (a type of pick with a flat blade), but that mostly just bounced off the rock-like soil.  Then attacked it with my 20-pound electric demolition hammer, using a three-inch wide bit.  That cut through the petrified dirt.  Here is a photo of my digs:

And a better photo of the trench.  The deeper narrower trench (16" wide, and 8+" deep) is for the footings.  This lower trench will contain the concrete without the need for separate wooden forms, possible because of the hard ground.

The wooden forms will sit on top of the deeper trench, supported by the wide shelf of the upper trench.  The foundation wall will be 24" high and 8" thick.  The concrete for both footings and foundation wall will be poured on the same day, with a break to pour the new front porch slab.  That will give the footings time to start firming up before filling the foundation wall forms to the top.

So now more digging to do, and forms to build.

Because the heat makes digging difficult, I have started on the less taxing kitchen countertop fabrication project, working on both projects every day.  That works well because I can't put my car in the garage until the concrete work is done, and the countertop project fills the garage.  The countertop is, again, going to be an epoxy lamination of maple strips.  The countertop is 12.5 feet long, and 30" deep.  I've just finished building the form on which the gluing will be done (lots of clamps will be required).  It's 13 feet long, and needed to be precisely level and flat, so the countertop will emerge from gluing perfectly flat and straight, and therefore fit without issues on the kitchen cabinet.  The jig/form looks like this:

So next post will likely feature these two projects.

Sasha, most recently rescued stray:

Waterbed Base — Part 3

First, a bit of history — waterbed history.

It was a big revelation when I learned that waterbeds were invented in the 19th century by a Scottish doctor to treat bedsore patients.  Bedsores (also called compression sores) are no joke.  They can quickly develop into open wounds that go down to the bone.  They can lead to very serious consequences if not treated properly, and even when treated diligently, they take a very long time to heal (often because the patients are elderly and infirm, with weak immune systems). 

Waterbeds were useful in treating bedsores because they distribute support for the body evenly.  I took care of my parents during the last few years of their lives.  My father had Parkinson's disease, was confined to a wheelchair, and when he was in bed, was unable to shift positions.  He developed a bedsore at a point where his spine impinged on a too-hard bed.  Although we caught it quickly, and treated it by keeping him rolled to the side when he slept, and applying special gel bandages, it took a year to heal.

I wanted to get him a waterbed to resolve any future pressure sore issues, but he was of a generation that associated waterbeds with hippies, so he steadfastly refused.  Got him a cushy pillowtop mattress instead.

Anyway, the modern waterbed was developed and commercialized by three San Francisco State University students over a period of several years, circa 1970.  By 1987, 22% of all beds sold were waterbeds.  Today, with advances in more conventional mattresses (memory foam, "sleep number," etc.), waterbeds make up less than 5% of beds.

Early waterbeds had simple mattress-shaped vinyl bladders contained by a wood frame.  When you moved, you made waves.  I had one of those starting in the mid-1970s, and used it for about five years.  That type of waterbed came to be called "hardside."

Hardside waterbeds are now available with varying amounts of fiberfill batting inside the mattress, which dampens the movement of water, reducing the waves.  You can buy one with as much or as little damping as you like.  That is the kind I now have; it has a medium amount of damping — just enough movement of the water to know you're on a waterbed, but no waves.

Hardside waterbeds do not come in "standard" bed sizes.  The widths are the same, but the lengths are all 84".  Twins, Queens, and Kings are all 84" long, and all prefixed by "California."  So if you're tall and have a twin-size waterbed, your feet don't hang over the end, like they would with a regular twin bed.  My Queen-sized waterbed size is called "California Queen" — it's 60" wide by 84" long.

There are now more modern waterbeds called "softside."  Instead of hard wood sides, their water bladders are surrounded by firm foam (although certainly a lot softer than wood).  The water bladder and foam edges are held together in a big fabric envelope or case.  These softside waterbeds come in standard sizes, sit on platforms, and use standard fitted sheets.  They're also damped, so no waves.  More like a regular bed, except with more even support.

The more even support is not only great for preventing bedsores, but it also eliminates cutoff circulation (pressure on a blood vessel), so no tingling or numbness.

And the water in waterbeds is heated.  That improves circulation, and any healing that may be needed.  And best of all, on those cold winter nights, no sticking your legs down between cold sheets!

But back to the construction of my waterbed base.

In Part 2, the lower (drawer) part of the base was complete, and the outer sides of upper section were attached.  The next step was to screw sleepers (or stringers) to the top of the drawers sections to allow for the installation of 1" of rigid foam insulation (to keep the heat in).

Next, another layer of 3/4" plywood was added.  This would support the waterbed mattress.

Corner braces were added to connect the outer sides to each other, and lower spacers installed to add strength and separate the outer sides from the inner sides.

Then the upper spacers were glued to the outer sides.

There are outer and inner sides because a single piece of plywood would not be strong enough to stay rigid, and getting in and out of a waterbed requires sitting on the edge  — and the edge of a piece of plywood would be nasty!  Also, the space between the inner and outer sides is perfect for more foam insulation.

And then the inner sides go on, screwed and glued at the bottom and just glued at the top.

And while I could have left this detail out, I added a wood fillet for a more accommodating edge for the waterbed mattress (doesn't have to squeeze into a sharp corner).

At this stage, I coating all the interior surfaces with epoxy to make it waterproof, even though there is a waterproof liner that goes outside the mattress.  And then the 3.5" wide maple tops are attached to the top of the sides.  This trim is what I will be sitting on, getting in and out of bed.

Before the liner and the mattress go in, the 300-watt heating pad is positioned, as is the temperature sensor (thermocouple), which both connect to the heater control (thermostat).

Then the liner and mattress go in and a garden hose used to fill the mattress with about 1500 pounds of water (using a special adapter).

And of course, I still have to build the drawers, and attach some maple trim to the far side.  I still need a suitable mattress pad and California Queen size sheets before it goes operational, but for now I need to move on to other things.

Other things being — concrete work for the six-foot garage extension and for the new covered front porch.  One of my neighbors does beautiful concrete work, and he will be between jobs in a few weeks so I need to do all the prep work for that:  hiring someone to cut and remove part of driveway, then digging for footings, and building foundation wall forms, etc.

The kitchen countertop and pottery studio cabinets will have to wait.  Sigh.

Waterbed Base — Part 2

This thing is BIG!

I built the three drawer sections of the base separately in the garage, and then used a hand truck to move them through the front door into the house, down the hall, and then carefully into the master bedroom.  This photo shows one of the sections pausing in the foyer.

Once all three sections were lined up in the bedroom, it was time to build the sub-base (which would raise the drawer units 2" off the floor).  The sub-base was made from 2x4s ripped to two-inch width, and then assembled into a grid using lap-joints at the corners and biscuit joints for the inner cross pieces.  This is how the two joints were made (then glued and screwed together):

Although it was unlikely that I would need to move the base after its initial positioning (and would not be able to do so after the assembly had proceeded very far — very heavy even without the 1500 pounds of water), I decided to glue quarter-inch thick felt to the bottom of the sub-base.  This would facilitate any needed sliding, and minimize scratching the bamboo floor. 

I then moved the three drawer sections aside and flipped the sub-base over onto the floor, then screwed all of that together.  Sometime around then, I started working on the ten drawers, doing some design work and then cutting out 20 drawer sides:

A piece of furniture this big and complex cannot just be built ad hoc; here is a photo of two pages out of at least a half-dozen design drawings.  It's of course not necessary to make these pretty and to scale if you're just doing them for yourself, but all the parts need to be there in their proper location, and the dimensions need to be correct and consistent.

Waterbeds are filled with hot water, maintained at a constant temperature with a heating pad that sits underneath the mattress and controlled with a thermostat.  If the water was room temperature, you would freeze, as the 70˚ Fahrenheit water would suck the heat out of your body.  So hot water (85˚ or whatever you choose) in the mattress.  But you don't want to heat the whole house, especially in the summer; you want the heat in the water to stay there, which means insulation.

On the top of the mattress, you can use a comforter or something like that.  On the bottom, I am installing one-inch thick rigid foam insulation.  The foam will go between several sleepers/stringers, installed on top of the three drawer sections:

Once the foam goes in, another layer of 3/4" plywood goes on top of the foam, which will then support the waterbed mattress.  Before that is installed, the outer sides were installed.  The plywood sides sit on maple trim pieces installed first — glued, nailed, with aligning biscuits.  The outer plywood sides are glued and screwed on.

The maple trim supporting the plywood looks like this:

The plywood sides were supported vertical by temporary brackets until the glue dried:

So I end this post at this stage, with the outer sides in place:

Next the rigid foam will be installed, with 3/4" plywood going in on top of that.  The lower drawer sections will get trim that will add another 3/4" to the outside of that lower layer.  The upper sides (which will contain the mattress) will ultimately be three inches thick; there will be another 3/4" plywood inner side added, separated by 1.5" spacers.  The sides will be capped by 3.5" wide maple, a reasonable width to sit on (hopefully that will work out).

And then of course I need to build the ten side drawers, and the long one on the end.  Always the drawers . . .