Another picture of the 1/2 inch deep burner bowl insert tray.

tray-side_view_2_slightly_from_bottom-shows_screws.JPG (21 KB, 68 downloads)

Top view of tray.

top_view_of_tray.JPG (31 KB, 57 downloads)

Tray in bottom of quart burner bowl.

tray_in_bowl_2-top_quartering_view.JPG (36 KB, 71 downloads)

After a four day continuos burn I shut it down for cleaning. It was still burning good but not as good. There was very hard build up of coal like stuff from the bottom of the small cup to the top[ of the drip tube. It looked like a termite ant hill thing from Africa . The stainless piano wire holding the cup melted on one side of the cup and a small part on the top of the cup as well.(Thats high heat). The pet dish was 100% clean (wow). The coal in the cup was so hard it went in the trash. I was so impressed with this burn I will continue testing. Maybe a disposable cup that could easily be swapped out hopefly while still burning?????????????
Give a lazy man a hard job and he will find a easier way to do it.

I am now testing a new design that is giving me the cleanest, hottest flames yet. Lets call it a "ramp burner" Its making white hot flames, with a blowtorch sound, and it sometimes hurts your eyes to look at it (but I can't stop looking at it!), kind of like an acetylene torch at certain settings. I noticed in my 2 years of dripping VO onto wood that it worked best when it dripped on a flat topped split side of a log, that was sloped slightly towards the air inlet on the side. The VO would vaporize as it ran down the log, and the hot flames would run the opposite way up the log.

I took my 1.4 quart dog bowl, drilled 5 -1/2" close together holes in the side, halfway up the bowl closest to where the air inlet on my stove is. I set the bowl right on the ashes in the bottom of the woodstove. Then I made a 2" wide x 6" long ramp out of sheet metal, and bent it into a mild 5-10 degree V shape as a channel for the VO to run down. I bent 2 little feet that support it up from the bottom of the dog bowl, and it slopes slightly down towards the air inlet. The bottom end of the ramp is just below the air inlet holes. This makes the VO vaporize as it runs down the ramp, and the inlet air produces large 8" long white hot flames roaring up the ramp. Very little VO ever gets in the bowl, mainly during startup or when I change the flowrate. It appears to work best when I drip near the upper end of the ramp. When I drip near the middle it vaporizes so fast that some flying droplets explode off the ramp. Much more experimenting with this design to come...

SunWizard--- now that is food for thought! Maybe I could make a spiral out of someting that the oil would cling to on the way down to the dish. I tried some other testing but nothing came close to the "little cup".

This morning I installed the outside-air-only lower burner bowl support can with the ventilated burner bowl containing the isolated vaporizing tray, this bowl has one row of holes located just above the vaporizing tray (one inch above bottom of the bowl).

Intermittent BLUE FLAME 1/4 to 3/4 inchs long from every air hole, these short blue sections of the flame finger are followed by long bright yellow/white fingers of flame all the way to the center of the burner bowl.

The burner tank temp went up by 20% for the same amount of fuel.

No, ABSOLUTELY NO, visable smoke can be seen coming from the chimney, I can see a bit of heat mirage but NO smoke.

Background - The previous burner test was one with inside and outside air and the standard ventilated bowl with one row of holes at the top of the bowl. This burned for 4 days fine but on day 5 I had to open the flue damper a bit to keep the flame yellow, had to open it more on 6 day, so much so that the soot in the stove ignited. I let the stove do a controlled runaway burn by continiously adjusting dampers to keep the max temp at about 800 deg f to burn out all the soot, took about 45 minutes for the stove to cool to about 200 deg f (room got HOT, way over 90 deg f), I then opened up all the dampers to burn out as much soot as possible. Once the stove cooled I removed the old burner assembly and used a poker to scrape the 1/8 to 1/4 inch layer of hard coal off the inside wall of the burner tank, this coal was caused by unburned fuel droplets being carried out of the burner bowl by the top air.

I installed the new burner assembly and lit the stove in the normal manner, it soon became clear that this burner did not like ANY air coming in from the top, I closed the upper combustion air damper completely, this caused all the combustion air to be drawn through the air holes in the burner bowl, WOW. Each air hole produces a long thin finger of flame that reaches from just in front of the air hole all the way into the center of the burner, the fingers are positioned just above the isolated vaporization tray. The fingers converge in the center of the burner and rise up as a nicely contained 3-4 inch diameter vertical columb of flame about 8 inches tall. The primary fuel droplet has to drop directly down through all this flame so it gets heated rapidly during the fall, once it hits the hot vaporization tray it explodes into a large number of smaller droplets, these get hurled back up through the flames a second time and crash onto the hot inside wall of the burner bowl. This bowl is apparently a bit cooler than the unvented bowl because in the unvented bowl these tiny fuel droplets immediately evaporate where they hit, many of the tiniest droplets do this in this ventilated bowl also but the larger droplets hit the wall, immediatly start to boil and evaporate, then run down the wall until they are totaly evaporated. None of the drolets ever reaches the bottom of the bowl, they all are completely evaporated by the time they get just past the air holes.

ALL the flame is very bright yellow/white and there are definite short sections of blue flame showing randomly from each air hole about 50% of the time, the remainder of the length of the flame finger is bright yellow/white

I can not see the vaporizing tray well due to all the bright flame but it appears to be staying clean due to all the heat from the flame fingers just above it. The fingers shoot out from the air holes at 90 degrees to the slightly sloping burner bowl wall, this puts there tips just a bit higher up than the air holes. The flame fingers come together directly in the center of the bowl and look like 42 little accetylene torch flames. The lower air damper is fully open. I suspect the burner needs even more air, next test.

This has only been burning for about a half a day so time will tell, sure looks promising, had to stand out in the 12 deg f temps today for about a half hour staring in disbelief at a smoke-free chimney, it CAN be done.

I will make up other bowls with 2, then 3, rows of 1/8 inch holes, may want to make the holes even bigger than 1/8 inch, lots to test here.

Since the top air is now closed I guess I can't call this stove a version of the Sanders stove any longer, it is a smaller version of the commercially manufactured Thermobile waste oil drip heater. There stove uses the isolated vaporizing tray, plus a bit of forced air. The military heater is a close second, no isolated vaporizing tray or forced air though.

One point - since there is no longer any air blowing down into the burner from above there is also no large amount of air moving sideways over the top of the burner, this air was carrying fuel droplets out of the bowl and onto the inside wall of the burner tank, I am still loosing some small percentage of fuel droplets over the top of the burner bowl, I can see tiny vapor trails as they evaporate going out of the burner bowl, they don't make it to the side of the tank, now they drop over the top of the bowl and fall to the bottom of the tank, don't yet know if there vapor is being burned or not, more testing. BETTER FOR SURE. More efficiency can still be gotten from this stove since I think some fuel is being wasted and is not making heat.

Tim - your latest experiment is great news. Keep up the good work. We're all anxious to read the results of your next experiment.

I had some success with a different arrangement, not at good as yours, but here it is for what it's worth: First the setup - my dogdish now has two rows of holes, one just 3/4 inch down from the lip, the other 1-1/2 inch down. The coffee can now has 4 holes in the bottom, 1 inch diameter, but two are always obscured by ashes in the stove, leaving the two nearest the fresh air damper to admit air. Upper air and oil drip is through a 1-1/2 inch diameter vertical pipe. The air inlet into this pipe is throttles by putting different sized washers on top, with the oil dripping through the hole in the washer. This arrangement works really well as long as there is a secondary fire in the stove keeping everything hot. It's possible to have it just burning oil, without the wood heat, but only at a high oil flow that burns dirty.
Now the latest modification: I hung a conical steel screen just above the lower row of holes so the oil dripped down the suspension wire to the conical point, then spread across the screen. The screen is heated by the flames above and below it. The oil runs across the screen like a wick, smoking as it approaches the edges. It either burns when it gets to the edge, or drips into the dish and flashes into flame/vapor. The flames from the upper holes are nearly invisible blue at the hole, turning to bright yellow where they change direction just above the screen. The whole thing streams a bright yellow flame down the length of the firebox. Smoke comes out the chimney, sad to say, but no soot builds up in the bowl after a day of burning - it's discolored from heat, but clean.

The screen has very heavy wire, cut and brazed into a shallow cone for some old experiment. It's about 3 inches diameter, but only about 1 inch deep. It has a big influence on the air flow, keeping it from directly hitting the bottom of the dish, and also keeps the drips from splattering.

Too bad it doesn't work as well as yours. Sigh. But, that's progress.

Cheers,
JohnO

Hey Tim, so you are only getting unheated outside air from the bottom now? How about trying some heated outside air next by running 1 or more stainless steel flexible gas lines up the stack? It can only help with better burn. How air tight is the door on your stove? You may want to consider adding a square of high temp ceramic glass, good to 1450F so you have a good tight seal and be able to watch the flame without disturbing the burn characteristics. I ordered a 6" square piece from Mcmaster and it was about $14.

A smoke tester can easily be improvised and would allow you to determine how clean your stove is burning without running outside and staring at the chimney and it will be a lot more accurate also. Use a vacuum cleaner to suck the stack gas through coffee filter material. You can take two nickel plated brass faucet feed lines, which are 3/8 pipe with a flange on one end. Clamp the coffee filter media between the flange to seal, stick one end into the stack, other end to the vac cleaner and suck for the same measured time period. Look at the paper for amount of smoke. It will be a very useful tool.

My ramp burner has been going for 5 days now, and its burning with no visible smoke as well. It also makes no deposits on the bowl, and little brown balls that can be easily brushed off the ramp.

The burner was showing some yellowing of the flames after 24 hours of burning, I shut the stove down to check the burner and I found that the vaporizing tray was about full of soft crud, most of this burned away after the fuel feed was stopped, from past experiance this likely indicated the crud was actually soft soot, harder coal does not burn away like this.

I cleaned everything and fired the stove back up, this time I added just a tiny bit of top air as a test, the finger flames are not nearly as prominent since the top air is the path of least resistance for incoming air.

When I fired this burner up the first time I let everything get up to temperature and then used an electric hot air gun to add a bit of forced hot air up the lower outside air inlet tube, the only change I saw was that the finger flames became much longer and the end of any visable flame had moved at least an inch away from the opening of the air holes? May need to allow some air in from the top and also add a bit of forced air in from the bottom to make up for the loss of draft through the air holes in the bowl?

I will swap in a burner bowl with two rows of holes next. Need to come up with a way to get the vaporizing tray even hotter, the shallow screen cone sounds interesting?

My old ramp was starting to sag due to high heat, so I made a new ramp out of U channel sheet metal, 2" wide with 1" high sides. still 6" long. This works even better, since the sides collect heat from the hottest part of the flame, and it also prevents splatter of the vaporizing drops exploding. The ramp is very low slope, about 1/4-1/2" drop across the 6" length, and I experimented with many slopes. Having the flames shooting only in one direction across the bowl allows bigger flames to have more contact with the ramp, and allows faster airflow which makes it burn cleaner, it makes a roaring sound like it has fan forced air by having the intake all going through 6 - 1/2" holes in one side.

The ring of small holes is still in the bowl but rarely gets any flames there except at startup. Making the ramp out of polished stainless like the bowls are would be even better, it might not get any deposits then.

This has been great, no flameouts even in high wind, and it often runs all day without having to mess with it. Much nicer than having to keep watching and stoking wood.

A couple pics would be worth a thousand words Sun.

I'm using a piece of tailpipe tubing for a ramp, which seems to be working ok. I cut the "drip" end at an angle so it would be easy to dribble oil into. The other end is cut off square, and is roughly centered on the dog dish. By juggling the stove draft and the washer size covering the vertical tube I now have flame shooting through the tailpipe while oil runs down the other direction towards the dogdish. I can peek into the dish and see the oil boiling and burning as it dribbles out the end of the tailpipe into the dish.

My arrangement doesn't burn clean like Tim's, but all of these ideas have been great inspiration to experiment.
Cheers,
JohnO

SunWizard -- About your wood stove - Is it front loaded or top loaded (is the door on top or in front), is the adjustable air inlet at the front end of the stove, is the bowl directly up against the air inlet (why does the air go through the 1/2 inch holes rather than over the top of the bowl?), is the flue out the top of the back or the back of the back, does it have a grate on the bottom of the fire box that allows ashes to drop down into an ash box or is the bottom of the firebox solid?

I am into the fourth successful day of burning a burner bowl with two rows of holes, both rows of holes are making blue/white/bright yellow finger flames. the second layer of finger flames has upped the temperature of the bowl enough that it is not producing coal, the vaporizing tray has just a small 1/2 inch sized wet spot in the center where the primary fuel droplet hits, and the small droplets that fly out and hit the side of the burner bowl almost all immediately vaporize where they hit, the other small percentage of larger droplets hit, boil, and start to run down the side of the bowl but totally evaporate in less than a quarter inch of travel.

Because of the higher bowl heat I have again completely closed off the upper combustion air. I am contemplating removing the upper air inlet tube from the stove completely.

The fuel drip tube now runs down the inside of this upper air tube so I will have to relocate it in some manner, still thinking about where to, and how best to, relocate the drip tube? I am thinking it would be better to use a smaller diameter tube (1/4 inch steel brake line) than a larger one (1/4 inch pipe), the oil would flow faster in the smaller tube so it will be in the high heat less time, hopefully this would reduce the amount of coaking of the oil flowing through the tube, not sure.

I have a 3 row bowl ready to test once this 2 row cruds up, or I get tired of waiting for it to crud up. Hopefully I can get a bowl hot enough that I can eliminate the vaporizing tray and again drip directly onto the bottom of the burner bowl.

I still have unburned fuel droplets flying out of the top of the burner bowl so was trying to come up with a deeper bowl by cutting almost all of the rim off of a one pint bowl and also cutting almost all of the bottom out of a quart bowl, then dropping the pint bowl inside the quart bowl to make the whole thing deeper to contain more droplets. I was looking for deeper bowls on the net and found something on a dog stuff website that might work, dog buckets, not sure why these are DOG buckets, well, maybe I know, but it is apparently unmentionable? There are several other buckets/pails described as having a flat side, more efficient I guess.

I have found only one referance to the actual size of a 2 quart SS pail, it indicated the pail was 6 inches across and 5 1/2 inches deep, just about right to replace a 6 inch wide and 2 1/2 inch deep SS bowl. They don't look to have wide rims but I can make some sort of an adapter ring if required. The 2-quart pails cost under $6.00 plus shipping on the dog stuff website but I found a similar one on ebay for $5.44 including shipping, ordered one to test. These deep pails will likely allow 8-10 rows of holes?

Next stove -- I am thinking I will use a salvaged gas water heater tank for this. A gas water heater already has legs on the bottom and has a 3-4 inch diameter tube running completely up through it's center, cut the tube off a few inches up from the bottom and an inch or so down below the top, this gets you a bottom air inlet as well as a smaller diameter flue outlet without having to do any fabbing or welding other than fabbing a door into the side of the tank and making up a pedistal for the burner, the water heater also has more tank surface area to radiate heat than my current 100-pound propane tank. There is also a threaded hole through the side of the tank about a foot up from the bottom where the gas control thermostat is placed, this could likely be used as the drip tube mounting point? (looks like not having to put a large air tube down from the top will make it easier to build)

Aside -- Planters peanuts has changed some of there 3 pound peanut cans, they are now made using some type of cardboard for the round section of the can with the top and bottom still being tin?

SunWizard -- I was wondering - It may be possible to develop your "ramp burner" concept into a continuous burning, off-grid, drip fed replacement for the intermittent high-heat-blast Becket style pressure or syphon burners in horizontal boilers or burner boxes?

quote:

Originally posted by Tim c cook:
SunWizard -- About your wood stove - Is it front loaded or top loaded (is the door on top or in front)

Side load, with a big glass window on the front.

quote:

is the adjustable air inlet at the front end of the stove

Side.

quote:

is the bowl directly up against the air inlet (why does the air go through the 1/2 inch holes rather than over the top of the bowl?)

The bowl is right against the door, and the bowl holes are lined up with the air intake holes, with about a 1" gap. The lip of the bowl prevents it going over the top, the bowl lip hits the door.

quote:

is the flue out the top of the back or the back of the back

Center of the back, and it has a damper to close that and then it goes up the front, across the top, then out the back. I keep that damper closed except when lighting since it radiates more heat to the room.

quote:

does it have a grate on the bottom of the fire box that allows ashes to drop down into an ash box or is the bottom of the firebox solid?

The bottom and sides are solid and firebrick lined. The bowl is sitting on about 2" of ashes which I kept in the firebox to allow easy adjustments of the bowl height and tilt. The tilt is important for the ramp to work best. The tilt and length of ramp would need to be optimized for the drip rate. My 6" ramp is good for between 1 pint and 1 quart per hour drip rates. 1 qt/hr is about where it changes from a drip into a steady stream, so I have a good visual indicator of setting. Higher than this, and some runs off the ramp into the bowl and burns much dirtier.

quote:

Originally posted by Tim c cook:
SunWizard -- I was wondering - It may be possible to develop your "ramp burner" concept into a continuous burning, off-grid, drip fed replacement for the intermittent high-heat-blast Becket style pressure or syphon burners in horizontal boilers or burner boxes?

Yes the flame, and size and shape of my woodstove reminds me of one of those. It would be even better to have the intake air on one end, and the flue on the other. My woodstove is too big for the size of flames I use, about a 8" horizontal white flame, with 12" yellow flames vertical from that. It might help to have a small fan to force the air if you wanted a larger flame. Mine is totally off the grid since its about as simple as it can get.

Tim- the only time I get oil hitting the inside of the tank is when I run the air wide open, but all my air comes in from the top for now.
I would like to build an airtight stove with air plumbed in directly to the can that holds the burn pot. That way all the air would have to go through the holes in the pet dish.
Right now I’m burning the one quart dish with a single row of holes and no tray or little cup.
I will try adding more rows of holes but with all the air coming in from the top don’t know if it will help. I am using a 30 gallon LP hot water tank but was thinking a propane tank might be better for my use cause I think the walls are thicker as I burn at a high rate.
I tried to post some pics the other day, one way put the pic right one the page it was huge so I deleted it. I got one up that was like a thumbnail and it could be clicked on and that took you to my photobucket site where all my pics there could be seen I deleted that one as well. I like how yours appear, how do you put ours on?
I light my heater with 1/3 cup of diesel and a map gas torch for about 5 seconds till the flame starts.
I burned 19 cubbies in Oct. 20 in Nov. 30 so far in Dec. I have a 30 gallon Polly barrel I pour into about once a week. I maybe selling my firewood in 2009. Next year I hope to pump the oil no lifting that way. At any rate it sure is much easier than making and burning about six cords of wood a year. Thanks again for the inspiration.

harry3 -- Actually, the longest burn I have had without a cleaning has been the 13 day burn using the same burner style you are using, one row of holes in the bowl and holes through the side of the burner support can, all with air coming in from the top. This did produce a bit of smoke from the chimney but the bowl burned clean. The bottom air only is producing the hottest burn and does not produce smoke or soot but the vaporizing tray insert does crud up after a few days. The outside temps got clear up to 62 degrees here today and I shut the stove off because the house was about 90 deg f. The vaporizing tray was starting to show some soft coal so I want to try the 3 row bowl tomorrow, the weather is supposed to cool back into the 40's then so will need some heat again.

Stove tank - A 100 pound propane tank is a bit smaller than the water heater tank and it is a bit heavier, right at 90/1000 thick material. I am still not sure which way I will go, I seem to be drawing about all the heat from the smaller propane tank and the flue pipe. The flue pipe temp at the brick chimney is within 20 degrees or less of the room temp so I dought that I would actually transfer any more heat from the larger amount of surface that a water heater would have, don't know?

I used 6 inch flue pipe on the current stove but I run the flue damper half closed so I think 4 inch, or maybe even 3 inch, flue diameter would be adequate for anything around a quart/hr or less, unfortunatly, I have not found any heavy guage flue pipe in the smaller sizes, just thin 32 guage galvanized gas appliance flue pipe, not sure I trust using that. One alternative is to use vehicle exhaust fittings, heavy enough but also a bit costly, a 10 ft straight length of 4 inch is a bit over $50.00. The 90 deg bend I am using as the lower air input tube is only 2 inch but cost $21.00, don't think I will use factory bends for the 4 inch flue, I will weld up the bends and/or "T"s from straight pipe, I don't even want to think about how much a pre-bent section of 4 inch exhaust might cost.

Pictures -- Directly below the place where you type in your posts it says "add attachment", that allows you to put pictures directly on this discussion, it won't show up directly as a picture in your post but it will always be available by clicking on the link in the post. I use a photo editing program to crop, tweek, and resize the pictures, about any such program will do, there is usually one on the installation disk that comes with scanners, they are also available as downloadable freeware programs from the net. I resize the pictures using 100 dots/inch and by making the horizontal size 6 inches they fit the screen directly, then adjust the JPEG compression percentage until the new compressed picture is less than the 50K picture size limit that this forum requires, 25K-30K is adequate usually and this size picture will show up quickly even over a 56K dial-up connection.

Startup fuel -- I originally used diesel and a propane torch but now I mix 90% diesel and 10% E85 ethanol (rough percentages, just by eye), I slosh a 2-liter bottle of this mix before pouring about a half cup into the burner bowl, the alcohol/diesel mixes with the slosh but as soon as you pour it in the bowl the alcohol starts rising to the top of the fuel and vaporizing, it lights instantly with a blue flame by using a B-B-Q lighter, after a couple seconds the flame shifts to yellow and away it goes. 91% isopropol rubbing alcohol works almost as well but you also get the 9% water in the fuel, it will pop and spit a bit when burning in the bowl. I suspect either yellow (methanol) or red (isopropal) "heet" would work as well as the E85 and there won't be any water in the mix.

Fuel prep - I have poured directly from cubees through a layer of old bed sheet but this is messy and the bottom of my 26 gallon fuel supply tank filled up with fine silt, the fuel supply tank outlet is from a standpipe about 6 inches tall in the bottom of the tank but I got silt above this before last winter was over and had to drain the tank for cleaning - PITA, I have three 50 gallon insulated and heated settling barrels that I use now, no water wash, just 3-5 days of simple settling holding the oil at about 90 deg f, I then pump the water and crud off the bottom of the barrels, then pump the bottom 5-8 gallons of wet oil off into yet another settling barrel, then run the remaining oil into 5 gallon jerry cans for transport to either one of my stoves.

Fire wood - Yep, I burned wood this last fall before it got cold enough to need heat full time, carrying an armload of wood in from the porch every couple hours reminded me why I started down this oil burner road in the first place, carrying in a 5 gallon can once a day, or once every couple days, is MUCH less work, and the house stays warm over night while I get a full nights sleep. BUT - I do keep a couple weeks supply of firewood on hand just in case (you may have to clean out your oil supply tank during the winter, sh-t happens).