The following should be interesting to readers using propane tanks to fire their ovens, especially Neo bakers using a 5 PSI regulator, and those considering switching to natural gas. It may also appeal to impatient types (I don’t know any
), and perhaps to others looking to design an improved gas-fired oven.Stone Alone
– The Blackstone Patio Oven doesn’t need the steel support platter and heavy duty shaft. Frankly, the stock burner setup uniformly heats just the stone with the rotisserie running. Getting rid of the extra platter hardware cuts the warm-up time in half and results in other benefits.
- Lower propane use (tank lasts twice as long)
- Quicker “clean cycle” for platter residue
- Higher possible stone temperatures (I know, who needs that? Maybe 5psi owners in cold areas and Natural Gas users)
- Lighter weight (mobile users, and manufacturers with unnecessarily high shipping costs and damage)
- Lower friction and substantially lower rotation torque to rotisserie motor (especially stock rotisserie and battery users)
- Fewer parts
- Same baking ability
DIY “Stone Alone” – There are lots of ways to make the conversion, but I’ve shown the easiest method I know using “off-the-shelf” parts and tools. Still, you will need to be handy (or have a friend) with tools like a drill, masonry bits, a countersink, hacksaw, tap and die set, and file.The first photo
shows individual parts. Starting from the top, you’ll need a stone. Either use the stock stone or buy an extra, and drill a center hole with a ¼” masonry bit. Continuing down the first photo shows a ¼”-20 countersunk Allen Screw about ¾” long which is what the pizza sees as it slides onto the top of cordierite stone. To countersink a hole in Cordierite, use a larger masonry bit for the initial shallow cut, then finish off the precise depth and taper by hand with a countersink bit. I say “by hand” because you want the result just flush with the surface -- it doesn’t help to use a drill. If you use a standard steel countersink bit (i.e non-masonry) by hand, it works fine and doesn’t seem to dull the tip.
Continuing down the first picture: lower, and to the right, shows a Fender Washer opposite a Coupler Nut. The Coupler Nut can be found at Ace Hardware in the bolts section. The tray number in my store was “2202-E” priced at $4.20 ea (it helps to think about how many trips to buy propane you will eliminate). The Coupler Nut and Fender Washer are zinc coated so let them sit in a cup of vinegar for a few hours just to be safe.
The Shaft is just 3/8” round stock purchased at Home Depot. After one end of the round stock is threaded (3/8”-16) and the other end is squared off to fit into the rotisserie drive, the shaft length is 14”. A grinder works to square off the end. Just grind the tip square, give it a test fit, and then extend the grind up the shaft an inch or so. You can paint the shaft if you like with grill paint, or season it with vegetable oil, but even if you don’t do anything it is generally quite durable.
This 3/8” shaft is much smaller and lighter than the stock shaft. However, a bushing needs to be added to adapt the 3/8” shaft to the 3/4" hole in the stock setup. Two methods are offered. The simplest is just to use a few washers held in place with spring clamps – simple and inexpensive – but the platter load is entirely supported by the rotisserie motor (which is fine if you are using the heavy duty motor). However, if you are using the lightweight Blackstone rotisserie motor, I would recommend supporting the load with a 3/8” Collar and set screw (Ace Hardware) just like bigger support collar that Blackstone provides. To convert the bushing/bearing holes to 3/8”, use a brass Compression Adapter (LFA-125) from Home Depot plumbing section shown in the photo. The nice thing with either method – washers or Compression Adapter – is that the rotating friction is much lower than stock and you eliminate that fiddly square key with a one-piece shaft that just plugs in.
As an added benefit, if you are familiar with the discussion around Clockwise vs. Counter-Clockwise rotation of the rotisserie motor, and you went with CCW, then you will be happy to know that the stone is self-tightening, i.e. when you launch a pie, that little friction when the pizza peel hits the cordierite ensures that the top screw remains tight.The second photo
shows an early version of the Stone Alone setup installed. It is noteworthy because it shows the Compression Adapter inserted into the upper bushing with a compression nut and a small Allen-head locking collar to relieve the rotisserie motor of the stone weight. The compression nut doesn’t actually wear out in my, and Bobino’s experience, but if you make a lot of pizza over a number of years, it is nice to know that you can just replace the nut and be good as new. Also note the upper stone support is an older design in this photo, and not the recommended Coupler Nut. The Coupler Nut is better.
Q: Do I need to worry about breaking the stone or bending the shaft? Nope. Not as long as you use the standard size stone. Don’t go with that cheapie ¼” thick Target stone (although it was pretty funny when Bob and I were standing there and the first pie tested created a thermal shock that broke the stone - sending stone, pizza, and sauce into the flame.) In typical use, the stock stone works fine for launch/retrieval of a heavy pizza plus aggressively scraping or brushing the stone.
Flame control becomes important once the extra thermal mass of the platter and the insulating air gap between the platter and stone is taken away. You might remember that I use a needle control valve. It works great. Bob uses the stock Blackstone valve and that works fine also. Going from memory here, in Bob’s setup, with a 10 psi regulator and valve on low produces a steady-state stone temperature of about 750F. So for those wanting an extended bake time, say between 5-10 minutes per pie, you may want to dial back the regulator pressure to achieve a lower launch temperature.The last photo
shows my current setup with a griddle replacing the cordierite. The griddle shown is 14” diameter from ShoppersChoice.com for $29 (http://www.shopperschoice.com/item_name_Cajun-Cookware-Griddles-14-Inch-Reversible-Round-Cast-Iron-Griddle_path__item_2161.html
). The careful observer may also note that the upper stone and housing has been replaced by an LBE-style hood. Longtime members might remember a year ago that I suggested Little Black Egg owners might try using their hood inside a Blackstone. A 22.5” Weber-style hood works fine and the high temperature paint is more durable than whatever Blackstone is using. All those fun calculations about radiation vs. convection and the “toast test” led me to “just do it”. One bake over a year ago, and I never went back. I get up to temperature a little faster and use a little less propane with this custom hood. But the simple answer for readers is as stated above is that the bake is the same: Blackstone = Bobino = my setup.
Hopefully others will put these modification options to good use. I don’t think that I’ve ever seen a Stone Alone Rotisserie design, but maybe someone has. All the stone-rotisserie setups I’ve seen (Blackstone, 2Stone, Deni, LBE, etc.) use a platter of some sort. By sharing this here, the idea becomes part of the public pizza domain for all to enjoy and encourages better oven designs going forward.