The Pizza Oven

Littler Monkey in the Oven

It all started last summer after reading an article in the June/July an issue of Make Magazine. The story described the construction of a DIY outdoor barrel oven made from bricks, welded steel parts, and a 55-gallon drum.   Able to bake bread, pizza, and other goodies from a wood burning file, such an oven seemed perfect for outdoor gatherings (keeping them outside!), and quickly made our short list for planned backyard additions.


This type of oven, known in Argentina as an "Horno Chileno", or Chilean Oven, is popular there for several advantages over traditional earthen ovens.  Because typical clay or brick ovens work primarily off stored heat, they require 1-2 hours of firing to bring them up to temperature and require periodic re-firing between sessions to bring them up to temperature.

Chilean Ovens, on the other hand, are "mixed-mode" devices that use a metal drum to create an isolated cooking chamber.  Since they operate over an open fire, they are much more efficient for occasional use, are ready to cook continuously in as little as 20 minutes, and can safely use scrap wood, paper, or even yard clippings for fuel.

Building the base

About six weeks ago, I was ready to start building, and created a base out of concrete block and brick.  Bricklaying is a messy process (at least it is for a novice like me), but it was fun and easy to do.  The most painful part is just obtaining the bricks in the first place.  I used about 320 tan concrete bricks, which I hauled in numbeous repeated trips from two local OSH stores.

Building the firebox

For additional heat resistance in areas directly next to the fire, I used heat-resistant firebrick.  Firebrick is much more expensive (and brittle) than clay or concrete brick, so I only used it where necessary, lining the firebox mortaring it together with refractory (heat resistant) cement.

For the bottom of the firebox, my trusty assistant Little Monkey and I welded together a fire grate from rebar and angle iron.  This would support the burning wood.

Welding fire grate

Fire grate installed

Little did I know that with the partially built brick structure and all the mortar that needed cleaning up that we were also creating the World's Coolest construction toy playhouse.

Construction worker on the job

For the cooking vessel, I scoured Craigslist andgot a $30 55-gallon drum that stored cooking oil in a former life.  I took it to an auto shop to sandblast the insides clean of paint, as food with paint fumes didn't sound very yummy.

To support the baked goods, I found two large industrial oven racks on eBay that I could bend to fit.  Each rack provided a generous 33" x 19" of cooking space, and fit almost perfectly inside, though I had to weld an extra inch of length to the barrel top to give them enough space.  I secured them with stainless steel bolts and nuts. 

Oven racks

Aka toy storage

Building the vaulted top

Now the tricky part.  For the vaulted arch, I mortared brick into the rounded shape using a framework of 2x4 cribbing supported by the barrel.  These temporary supports--when removed--would form an air gap where heated exhaust gases can warm the barrel on their way out to the exhaust chimney on top.

My new good friend Amazon Prime provided the parts for the chimney, including a 6" galvanized pipe, fire safe exhaust cap, and cast iron damper.


While the magazine article provided good general guidance, it lacked specific instructions in many areas, especially in the regards to the metalwork.  Fortunately, the absence of exact requirements left ample room for blissful improvisation and it's evil companion Online Shopping. 

Ready to use drum lid

Insulating oven door

The oven front was biggest metal part requiring fabrication.  The design required a heavy hinged door with a rest stop mounted to a form-fitting ring attached to open end of the barrel.

Surprisingly, I found an amazing shortcut in the Bustin Waste Drum Cover.  Complete with a naturally heat-resistant powdercoat finish, it almost exactly matched the carefully constructed metalwork in the article.  All I needed to do to complete it was to paint it black, add a spring grip to the handle, and insulate the inside with ceramic batting and an inner wall I fashioned from the old drum lid.

For the fire door, I found a ready-made fireplace cleanout door, fashioning a simple locking handle of of bar steel to complete it.  Similarly, for the cleanout, I used an existing metal air register as an air grille, adding a tray formed from galvanized sheetmetal as an ash drawer.  Both looked better than anything I could fashion from scratch myself.  Thanks again Amazon Prime!

Fire door

Ash drawer

Door thermometer

Inside heat sink

For finishing touches, I added a thermometer to the door and, after a test firing, added large heat sinks to the inner and outer bottom surface of the drum with the thought of increasing heat conduction performance and air circulation.

Here is the completed oven.  Once put together, IMHO it looks fairly legit.

All hail Smoko, the Chilean

  

It's taken a couple of firings work out some initial bugs.  For instance, initially I didn't leave enough expansion space around the barrel front and this caused a little expansion cracking when brought fully up to temperature.  Wood fires are also very sooty, and I had go back and seal the fire door and barrel surround with silicone to better contain the smoke.  Lastly, while I kept the original chimney height short for aesthetics, getting smoke blown in our faces was fairly fun-free, necessitating extending its height a little bit.

We've also learned a few tricks, such as first building a good fire and waiting for it burn down to hot coals before cooking.  That's when we've seen the oven reach its hottest temperatures, around 600 degrees F, perfect for crispy pizza.  We've also heard that hardwood burns much cleaner and longer than softwoods, so we're looking forward to trying that.

We're still learning how to best take advantage our new Chilean friend, but are sure it will continue to be a hit for many summers to come.



 

Fun with DIY Unlicensed Medical Devices

FDA, AMA meet DIY

I'm not a doctor.

Nor do I play one on TV.  But who needs medical credentials when there is good making to be done!

Recently, I had the opportunity to build something different--a quick project that was simple but rewarding.

A few months ago a good friend mangled her arm in ATV rollover.  After several surgeries, her parts are back together (more or less), but her recovery entails daily hours of physical therapy to regain flexibility and strength.  The official routine is done with simple weights and manual devices, is repetitive and monotonous, and requires constant focus to maintain proper form and pressure.

As far as I know, being shirtless conjoined twins is not a requirement for the therapy shown.

I decided to I might be able to help with a particular exercise, one to extend the wrist range of motion in rotation.  My first thought was that there ought to be plenty of commercial mechanical devices on the market to help automate the process.  I looked, but except for a few vague references to mostly description-free items that could be purchased overseas in bulk, they didn't exist... yet.

It could be useful, I thought, to use an electric motor to perform the rotation, as it could rotate back and forth, performing a perfectly repeatable motion with a user-adjustable torque limit in each direction.

The "Wondermotor"

The first order of business was to find a suitable motor.  By lifting a one-gallon jug of water at the end of a 1-foot stick, we estimated that we needed up to 8 foot pounds of torque (since one gallon weighs 8.3 lbs).  That's pretty tall order for a low-voltage motor, but I found exactly one readily-available candidate--a 12-Volt Wondermotor ($69) on Amazon--that fit the bill.

It has a built-in worm drive to slow the motion and some impressive specs, and I'll have to remember this one when it's time to build powered go carts for the little Monkeys.

It used to be that you had to make stuff like this yourself

For power control, I got a small PWM motor speed control board ($10), also from Amazon, along with some switches, connectors, and miscellaneous parts.  Some pipe from the hardware store, and a cheap angle finder gauge from Harbor Freight completed the parts list.


I mounted all the components on some scrap lumber, elevating the motor tied to a block of wood with a pipe support strap.  I built a handle out of a bicycle grip, a galvanized pipe nipple, and PVC pipe fittings, and mounted it to the motor through an oval hole drilled in the pipe nipple.

For some reason this reminds me of that Simpsons episode where Homer bulks up just one arm and uses it to hustle folks arm wrestling.

To power the motor, I used a spare 12-Volt wall wart wired as input to the motor speed control.  I wired the output of the control to the motor, passing through a two-way momentary DPDT toggle switch to allow the motor to change directions.

The idea was to have motor stall when the user's wrist reached its end of motion, suddenly increasing the load.  By adjusting the power/speed control, one can get the unit to exert the same force for every rotation.

Here is a video of the device in operation during initial trial tests...  

I got lots of funny looks from the security guards that morning.

and upon delivery.

The Outside Bathroom

Summer.  

Hot days, pool parties, and kids stomping through the house.

Ah, about that last thing... first there was the guest's seven year old who was left to use the bathroom unsupervised.  He peed all over the floor and Mama Monkey had to clean it up.  Then there were the trio of girls that decided to give themselves a house tour.  We found them poking at our parakeets through the bars of their cage.  And of course there were the occasions of sunscreen smeared on the cabinets, sticky thighs taking a break on our suede sectional, and numerous instances of dripping pool water on the carpets on the way to the facilities.

For the last few years, Mama Monkey and I have shared a running joke:

The Outside Bathroom.

How splendid, we imagined, would it be if we could conjure up a bathroom for the exclusive use of our backyard guests?  Then we could host gatherings as often as we pleased, but keep the back doors locked up--as tight as the overstretched skin on the cheeks of an aging Hollywood actress--keeping the party outside!

This year, we really gave it some serious thought, and realized... well..  why not?

We being us, this couldn't be just a hole in the ground or a composting toilet or anything else gross like that.  While I jokingly referred to the project as the Outhouse, it always had to be the real deal--full flushing toilet, porcelain sink, and running water.  Time was short, however, as I only had one month of weekends to build it.


The plan was to build a small standalone building from the ground up, and tuck it beside the side entrance to our garage.  I wanted to use the same stucco-textured Hardie Panel concrete siding boards that I used for the barbecue islands last summer.  Since they come in 4x8 sheets, a 4x4 building would be ideal, and just large enough to comfortably fit a toilet and small sink.

Conveniently, the drainage could run to a nearby sewer cleanout at the side of the house, so I started by building an elevated platform built with pressure treated lumber.  The raised floor height would allow space for piping below the toilet and provide the proper 1/4"-per-ft. down slope to the cleanout.

Above the platform, I framed the structure with 2x4 and 2x2 lumber, keeping the side walls half normal thickness to maximize the inside space.  The front would need to be full depth, however, as I would have to frame and hang a door inside of it.




With the walls open, I roughed in the plumbing and electrical.  I used armored cable to wire up a combination light and vent fan, connecting them and a switch to an AC power inlet jack so the bathroom could be powered by an extension cord.

I connected water supply lines to an RV-style garden hose water inlet connector.  For waste venting, I ran a pipe up and out the back wall, topping it with a custom vent cap I designed and printed on my 3D printer.

With those two items complete, I insulated the walls with rigid foam to keep out some of the summer heat.


The stucco-textured Hardie Panel made easy work of the exterior.  They screwed right on with self-tapping screws.  Then, add a little paint applied by some industrious volunteers and presto! a perfect match for the house.

The only puzzling dilemma was how to finish the exposed panel edges at the corners.  In the end, I ripped PVC rain gutters to make inexpensive waterproof L-channel trim: functional, yet a fraction of the cost of raw PVC angle material.

For the roof, I chose a simple slanted shed roof with Ondura Fiber/Asphalt Roofing Panels mounted to a 1x6 frame.  To avoid penetrations in the surface, I routed the output of the exhaust fan to vent holes under the eaves,

One of the benefits of having only sixteen square feet is that one can afford to splurge a bit on finishes.

We chose materials to keep the bathroom water resistant, including FRP (fiberglass reinforced plastic) walls, and PVC wainscoting, baseboards, crown molding, and trim.

For flooring, we chose a nice porcelain floor tile, and set a single box with crack-resistant thinset and waterproof flexible urethane grout.

Finding a proper sink proved to be a challenge, but a tiny pedestal sink from Signature Hardware fit perfectly.  To hold the sink, I fabricated an aluminum bracket with threaded posts and imbedded it in the wall before skinning it.  The finished floor height ended up being about 3/4" lower than estimated, but I was able to compensate for the difference using my 3D printer to fabricate an extra spacer ring to fit between the sink and pedestal.

After five weekends of planning and construction, finally, here is the completed bathroom.  During construction, the floor platform rested on temporary casters so the bathroom could be pulled out to access all sides.  After completion, it was simply rolled back into place.

The unit it technically portable, since the sewage line connects with hose clamps, power is plugged in, and water comes from a garden hose.  The floor platform is even purposefully open in front and sized to fit a forklift or manual forklift cart. 

However, it currently works splendidly well where it is.  It has proven to be super convenient and a big hit with both guests and family.

Next, up, the pizza oven!

The Secret of Monkey (BBQ) Island

Avast ye mateys!

Okay.  So maybe talk like a pirate day was last month, but I couldn't resist it given my fond memories for that other Monkey Island of lore.  The latest project on the Monkey grounds has indeed been an island, albeit a far more terrestrial barbecue island and not nearly the maritime destination as its electronic diversional counterpart.

Ahoy Matey!

They say a man's home is his castle.  "They" obviously refers to people who have never been married, or they would surely know that instead a man's home is in fact HER castle, and that includes all the inside rooms, common areas, kitchen, bathrooms, any place that doesn't have a greasy vehicle in it or hasn't been explicitly designated the Man Cave.

The only other refuge that qualifies for a similar variance is a place dedicated to the practice of that distinctly sooty- fiery-burny (and hence sufficiently "manly") style of cooking:  the Outdoor Kitchen.

I must admit that even outdoors, I do very little of the cooking, but that's no excuse not to embark on another construction project.

While we already had a standalone stainless grill and gazebo, what we really needed was a more complete solution that lessened the need to shuttle back and forth from the inside, giving flying pests more opportunity to breach the "castle's" outer perimeter.  I had previously laid water pipe and electrical conduit underneath the patio in preparation for an addition like this, but didn't know what final form it would take.  We decided to build a pair of islands to straddle the grill that could provide storage, work surfaces, a sink, and refrigerator.

Bottom Rails

I started by laying out the base using some galvanized steel channel track I got off Craigslist.  A fellow was selling seven boxes of components from an expandable wall framing system.  These wall sections are designed to each scissor open and extend out to instantly frame a 4-foot length of partition wall.  I got the whole load for $35 and salvaged them into their component studs and track sections, which provided more than enough material for entire project.

The parts came together quickly using just tin snips, vice grips, and self-tapping screws, much like a large Erector Set, and at the end of the first weekend was ready for siding.

Rough Framing

Adding composite lumber feet

However, working with jagged sheet metal was not without its downsides, as the skin of my fingers and palms collected more holes than the plot of Batman and Robin.

Both islands framed

Cutting stucco siding

The normal way to create a stucco finish is rather messy and time-consuming, and involves first siding the boxes with plywood, then wrapping them with mesh, and then laboriously applying a layers of mortar and stucco to the outside.  Too inefficient for me.

Fortunately, JamesHardie makes a stucco-textured siding panel that can be cut with a circular saw (with diamond blade) and simply screwed into place as a standalone covering.  I found it at the local Lowes for $37 per 4x8 sheet. 

Attaching siding over moisture barrier

After wrapping the framing in a plastic moisture barrier, I simply cut and screwed in the Hardie Panel, countersinking the screw heads so I could caulk over them later.

My plan was to simply screw it into place, caulk and fill the corners and screw holes, then paint over the whole shebang to match the house.

Framing overhangs

The overhanging edges of the counter needed special attention, so fortunately I had a little help.  We boxed overhang using galvanized studs, and then clad the countertop with pressure treated outdoor plywood.

Working in tight spaces

Both little monkeys did their best to help.  Though they really thought the open cabinets made a great clubhouse and really preferred we not finish it.

I sealed the plywood with RedGard waterproofing membrane, then screwed some steel angle iron to the edges to keep the plywood from curling up.  I applied a layer of cement backerboard using thinset and screws.  Then another layer of RedGard went on top of the cement board, both to waterproof it and prevent the tile from cracking.

Reinforcing edges

Work break

My first thought was to leave open shelves for simplicity, but I was convinced that adding stainless doors would be a worthwhile addition.

Stainless doors

From BBQGuys.com, I ordered a tilt-out garbage can holder and two sets of double doors, one with a built-in deep storage drawer.  Costing a grand total for the set, it was by far the largest expense, but in the end so worth it.

Cutting slate tile

We always planned on tiling the top, but were unsure of what type of tile to use.  In the end, we found a great deal on clearance natural slate tile at a local tile store for $1.99 a square foot.

Finished tile

Using a cheap tile saw I have purchased years ago at Harbor Freight (one of my favorite stores), I was able to quickly cut and set the tiles, then finish the top off using a water resistant grout (no sealing!).

Prepped for sink

I dropped in a composite granite bar sink into an opening I had left in the countertop.  I plumbed the supply lines to pipes I had laid down before the patio concrete was poured, and I routed the drain lines to a dry well I dug in the dirt behind the island.

Mounting sink

After adding plumbing and electrical outlets, the only one last final touch remained.

I planned to use a small bar refrigerator that I got for free off Freecycle a number of years ago, but it was clashingly black in color.  This presented the perfect opportunity to try out a new product I'd read about online.

Ugly fridge

Thomas "Liquid Stainless Steel" is a paint-on system that claims to give the attractive look of "brushed stainless steel" as "commonly used in chef's kitchens".  I was a little skeptical, but at only $25 for their range/dishwasher kit (and a fridge that was free in the first place), I had little to lose.

Uglier fridge

The kit comes with a small foam brush, a can of clear protectant, and a can of "color" coat that consists of fine stainless steel particles suspended in automative paint resin.  You're supposed to carefully brush on a few thin coats of color, followed by up to three clear coats of top coat to add shine and protect the finish.  The instructions warn that the first few color coats will look quite bad, but not to worry.  I certainly found that to be the case; the initial coat looked horrible, but the look indeed improved with each successive coat.

Somewhat less ugly fridge

In the end, I was pleasantly surprised.  While by no means a replacement for stainless steel, it resembled what it was; a faux painting technique that evoked a stainless-like look.

At the right angle and a distance of 10 or more feet, it looked fairly convincing, certainly enough for an appliance that would live outside. 

Faux Stainless

So in the end, did it give the look of a "Chef's Kitchen"?

Hmm. Well--especially close up--no Thomas Keller would probably not be terribly impressed.  But Helen Keller... maybe.

So here are pictures of the final product.

In the corners of each island, I later drilled large holes to mount shade umbrellas for additional sun protection, also lining the paths for the umbrellas shafts with pipe that could channel any rainwater to safe outlets underneath the islands.