Archive

Monthly Archives: January 2019

dsc09110

Core Oven: refractory board rated to 3,000 degrees.

I thought I’d make my own super-efficient Rocket Mass-Heater for the ranch, to replace the dangerous old cast iron wood stove. A Rocket Mass-Heater burns about 80% less wood than the old stove, can run on pellets as well, produces no smoke, few gasses, and will keep the house warm all night with no fire burning. It provides a radiant heat source via a stainless steel bell, as well as a large radiant mass that warms to a few hundred degrees which then radiates heat for 8 to 10 hours after the fire has burned. It can heat the house for 12 to 24 hours for one hour of burning- depending on how well my mass structure absorbs and retains heat. I will build that up at the ranch, using aircrete; concrete blended with super foamed soapy water. This reduces the weight of the concrete mass by 60-75 percent, and allows the heat to permeate the mass.

dsc09107

This is the Walker J-Stove design. I bought the layout plan for $20 online. Brilliant.

The interwebs are awash with bad Rocket Stove designs. Many cores are created with bare steel using old gas canisters. At 1500 to 2000 degrees in an oxygen depleted environment, steel undergoes a process called spalling. Essentially it rusts without oxygen, or more precisely it is the effect of reshuffling the iron molecules wherein they lose covalent bonds and layer like sheaves of paper. Refractory material is the only media that can survive the temperatures in the core and stack. I found the best understanding of the forces at work were from Masonry Stove builders, in particular Walker Design, who offers a J-Rocket core design to keep us diy dinks from burning down the ranch house. My design is a hybrid, as the stove will stand alone, as will the mass-heater. This is borrowed from another solid innovator, The Honey-Do Carpenter. I’ll be using his specs to create the concrete foaming gun, and modifying from his prototype of a light weight mass heater separate from the rocket stove.

dsc09108

I added this air-flow channel, bringing fresh air to the riser to encourage the venturi and oxygenate the superheated gasses for a complete burn.

dsc09109

The air splits into three channels, that combine into one, with the three channels still delineated at the top. This opens directly into the stack.

dsc09105

I found this round refractory tubing rated to 1500 degrees, perfect for a venturi stack, or chimney. The Walker design uses the same media as the core, so that stack is square, which limits the gyre.

dsc09106

I wrapped the stack in heavy perf aluminum, and tied it with stainless steel wire. 

dsc09112

Now I wait for the fireplace brick splits order to arrive, to line the inside front of the firebox. This protects the delicate refractory media from the wood fuel.

dsc09115

The fire brick arrives, and I run a hot burn to temper / shrink all of the media, prior to spackle with high-temp mortar.

dsc09119

As the fire climbs to temperature, there is an initial column of smoke.

dsc09120

In a few minutes we are at temperature, and the smoke is gone. All wood is reduced to gas, and even the gasses are burned. Her core temperature is 1,500 to 2,000 degrees (hot enough to melt bronze and steel). I can hold my hand against the walls, they are warm to hot.

dsc09124

Operating at full burn. 

dsc09122

Only the bottom end of the wood burns. These board-remains were 4 feet long, and slowly digest into the jet of flame. The soft roar of the air to flame is why this is called a Rocket Stove.

dsc09130

The remaining cinders are the remains of the last few cooler minutes of burning, as the full incinerating force drops.

dsc09137

This is after the next step; encasing the delicate refractory core in a heat-safe and tough shell.

dsc09138

The refractory core is bedded in rock-wool, a fireproof spun silica insulation that allows no air movement. The outer shell is hardy backer board with a tough outer shell, ready for tile. I used an industrial cement and seam-webbing to join the board. 

dsc09140

20 feet of angle iron, and a few steel scraps, welded into a sturdy frame. 

dsc09113

The stainless steel 15 gallon drum goes over the chimney column. This acts as a heat radiator. 

dsc09139

I cut this perfect circle to sleeve over the chimney. Next I will cut a small hole on the outside for a stove pipe connection, and another to fit to the mass heater (another build for another day). 

Lots more to do: support the stainless drum; put on low legs; create gravity-assist wood feeder of wide square-stock tubing that is removable; resolve the stove piping; tile it; maybe make a pellet feeder. Then design up the mass heater for assembly in Montana.

dsc09098

I turned the house into a giant jiffy-pop. (movie reference alert: Real Genius)

Spreading industrial grade perforated aluminum over the top of the blown-in-insulation has been on my radar for a few years. It is primarily an upgrade for blocking summer heat radiating through the roof: mitigating about 97% of the radiant attic heat. In warmer climates the foil is attached to the rafters, and has little pinholes to allow convection to move the hot air up to the roof peak. The foil I used is made to be laid flat in hot/cold climates; it has larger punched perforations allowing moisture/condensation to pass through. Laying it atop the lofted insulation stops the cold air from pressing down and sinking through. Cold always drives downward, and the house heat meets the down-driving cold and creates a fast convection circuit that rips heat out of the house. With the diving force of the cold air blocked, the house should be cozier. Mostly though, it is for our triple-digit summers.

I pre-cut sections of foil out on the deck, then used a 10 foot run of pvc with a nail taped to an end to pierce the foil and push it into place. Before pushing it I added upright tabs of aluminum heat-tape, and after pushing it into place, used another pvc run with a T ending to press the tape down onto the adjoining section of foil cover. It went pretty well, but standing on a little board by the hole for the ladder in a slippery tyvec suit and finding physical leverage to make things go where they needed was a bit like doing yoga-for four hours.

dsc09099

dsc09101

The giant exhaust fan (Whole-House cooling for summer) was mostly snugged with foil. I figured that I couldn’t fenagle a 3×3 foot foil section to cover the spot behind the vertical board, or I may have just been tired out and given up…

dsc09102

I could just reach the far corner if I linked two 10 foot sections of pipe. The pipe then becomes drunken and floppy way out at the end, and the foil slides off the pushing nail and won’t allow the nail to re-pierce and gets belligerent about moving at all.

dsc09104

Years ago I built this foam air-lock to cap the attic ladder. I added it after I had hired an outfit to blow insulation to an R-whatever on top of the here-and-there sections of fiberglass batting already in place from the previous home-owner. (bcs I just can’t stop tinkering)

DSC09077

View of the ranch coming in the high route, still passable with little snow.

Elizabeth and I took the pets (Nora, and her cat brothers) for a Xmas closer to Santa, up at the Montana ranch.

Version 2

Nora insists walkies be taken up on top.

DSC09059

Snow is sparkling out of thin air.

DSC09068

Cold air from the plains meets the warmer air over the mountains with cloudy drama.

DSC09071

Snow-virga drops toward the pyramid shaped Iron Mountain.

DSC09022

Some xmas loot under the little ranch tree. E e-bayed ranch themed ornaments.

DSC09025

A leather saddle, fur covered chaps with matching boots,  cowboy with lasso, a Rudolf tree topper, and many more!

DSC09023

Egg ornament with tiny stage coach.

DSC09043

Nora shares her bed with Xander, awaiting Santa.

DSC09042

The constant wind directly evaporates the blowing snow, lees and gullies collect what they can.

DSC09034

The ladies.

DSC09076

A patch of sun down on the Highwoods illuminates the mountainside near my cousin’s ranch. We went over for a visit, and looked out their picture window framing the other side of the peak.

DSC09020

This black-faced wasp nest was sited to eat the caterpillars infesting the willows last summer. Friendly wasps, as long as everyone respected a bit of personal space.

DSC09014

One of two contraptions made in SLC for a specific ranch issue: any guesses?

DSC09015

Unit one in position.

DSC09016

Unit two in position.  guesses?

DSC09078

This is a view of mystery wiring in the root cellar that should never have worked, but did until it didn’t. The white unit at the bottom is a ceramic light fixture with an electrical plug. The electrical plug connected an extension cord into the kitchen, via a hole drilled in the floor, to power the refrigerator. The metal box holds the incoming electrical line, where it splits to go upstairs and to power the old defunct central heating system. The hot wires are the black wires bundled together with electrical tape, the neutral wires are the yellow and white. Note that the power to the light bulb and the fridge’s plug-in have no hot wire to power them. The ceramic fixture acts as the conduit for the neutral wires, and this somehow powered the fixture. Yikes.

DSC09082

I connect the wires without the fixture to make a correct circuit, then use the wiring to the old heater to run through the floor to the fridge.

DSC09083

I wire in this shiny new floor plug, and below it can be seen 4 of 21 holes to the basement I patched years back. At top is the extension cord we had run from a wall plug to power the fridge.

DSC09084

With the fridge working, I add a pig of wiring to the light fixture and tie it in to the corrected wiring- and it works. I remember an upstairs light switch that has the switch removed and wires bound together with athletic tape, and find the hot and neutral wires wound together under the tape (rather than bound separately  and taped together). I end them correctly and many other upstairs lights that have never worked, work. And the fridge runs better, and the ceiling lights are all brighter. Since we’re looking at the water heater, it doesn’t work again as the elements were all burned out by a mistaken breaker throw on Rodney’s hunting trip in the fall. I couldn’t find my pull-tool for the elements, so this will be a summer fix.

DSC09047

Our first two nights we heard a whomp on the roof as this packrat jumped from a big pine tree onto the roof. I found his interior access to the rooms and blocked it, and he headed through the walls and into the basement. Where I had baited the trap. E heard his squeal as the trap hit him at midnight, then he dragged the bucket around for hours keeping her awake. I slept through it all, then gave him a quick end in the morning with the axe. Usually if you think there is one in the house, well, a few summers back we trapped/killed 13.

DSC09049

Packrats are poorly named, as they are more like a bunny-squirrel. I buried him in the corral, using the pickaxe to break the frozen ground.

DSC09054

We decided to come home three days early, as a massive arctic front was moving in. We drove back ahead of the arctic air mass with hard effect for 400 miles (of 560 miles) of pre-storm storm: hitting us with 80mph winds that closed roads to semi traffic, past plows that had slid off the road, through long sections of unplowed mountain roads with road edges defined by locals missing the edge and somehow making it back on track, in Idaho we hit freezing drizzle shifting to black ice on the highway and glazed the windshield, and a final 100 mile run of headwind that dropped the truck to 10mpg. Still, better than driving back in or after the actual storm.

DSC09091

-15 up north on our route is +15 here, 30 degrees warmer is still plenty freezy. The Utah yard pond waterfall emerges from under an icebrella.

DSC09094

Overnight drops to 7 degrees F and waterfall is nearly ice-encapsulated by morning.

dsc09097

Another single digit night and waterfall encapsulation is complete. Inversion is at a dangerous 159ppm, bright yellow air is hazy across the back yard and the surrounding mountains are smeared out.

DSC09093

Utah cold sometimes requires a jacket. (Mystery Fix Answer: nesting deterrent for Robins and Wrens at power lines to the house and tool shed.)