Fascinating thread. One day...
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Fascinating thread. One day...
HiQuote:
Originally Posted by Ralph1Malph
My flue, 6 inch, is approx 3.5 metre's and works great. When i built my prototype to test the idea it was 4 inch and about 2 metre's that worked well also? for the air entry into the primary pot iv'e got 4 x 17mm holes
You'll work it out and it will work reliably
Cheers db
If your oil is burning in the lower chamber, it sounds like you have too much air going in there through the primary air holes. I have six holes of 6mm diameter. Remember, you only need enough air in this part of the burner to vapourise the oil in the bottom.Quote:
Originally Posted by Ralph1Malph
Also it sounds like you are leaking air somewhere and losing your draft. Normally if you have too much air in the primary burner it will roar like hell and you'll have lotsa black poo tinkee smoke.
Orright,
Pics to follow but we are nearly there.
Spent a week fiddling and today we built to spec.
Using a galvanised washbasin about 14" dia as lower pot.
Machined a lip into 10mm plate for the lid and bottom plate.
I only have 110 mm pipe so the flue is 2.5m of this.
Two truck brake drums form expansion and radiator chamber.
Here's where it gets weird. I have 4x 8mm holes in bottom plate and secondary burn chamber is 4-5" 130mm pipe...but it seems to work best with only 8x 10mm holes in a ring about 2/3 way up:eek:.
With this config, we could get a sustained secondary burn with vclean emmission. Interestingly, it was almost silent, no vicious induction noise as with prototypes.
Will fiddle more tomorrow, as this trial was with the lower pot about 1/3 full of oil (2.5 litre). It was hot enough to peel the paint and grime from the brake drums and 1.5m of flue, but after 1 hour, nowhere near cherry. BTW, by my reckoning, it burnt about 1 litre per hour so happy with that.
I also made a trial secondary chamber with approx 40 holes but simply could not get it to secondary burn. It's also cool when the oil in the lower pot crackles and boils (not good but we made it happen).
Happy with the build so far but something still not quite right. Even though burns clean, I was seeking a more forceful, hotter burn.
Any tips anyone?
Ralph
I hope that you are not going to use it with the primary pan containing any depth of oil. Should you get a bit of water in the bottom, it will eventually boil and the oil will literally erupt. It could be very dangerous. My experience with only a few millimetres of oil in the bottom containing a teaspoon or less of water were alarming to say the least. It crackled and roared belching black smelly smoke out of every available orifice, it also spat droplets of smoking and burning oil out of the secondary air holes. fortunately they were small and never made a lot of mess but the smell was bloody horrible.
The idea is that once burning, the fuel is only added at the same rate at which it burns so there is rarely any measurable amount of oil in the pan except a small pool immediately under the feed trough
As for the configuration of your holes,... "If it works and does not smoke or smell, you must have it right. Obviously you have discovered another working combination.
Eureka!
Have stumbled upon the correct ratio of holes, air, flue, oil etc.
Works well, and clean too.
Now just putting on some legs and better arranging a dripper and *hey presto* should be ready for the final modification.......
Oh and pics when finished.:angel:
Ralph
It's great when it happens.
I'm sure you'll enjoy working in your shed a lot more now. I'm really looking forward to the pics.
Great news :) do you have an estimate on litres/hr i'd be interested to compare I run around 2.5/hr
look foward to seeing your pics
db
Very early trials indicate around 1.5 litres an hour, but I expect that will go up a little as I have not bothered to fine tune too much.Quote:
Originally Posted by db65boxer
Hope to have it home this W/E and put to use....I have added some bits to suit my purpose. Have to wait and see:p
Ralph
Well,
It's nearly there!
I have it home, and have been fine tuning it.
Attachment 37328
Attachment 37329
Attachment 37331
Attachment 37332
Attachment 37333
The first pic is the complete bottom with pan, bottom plate and secondary burn chamber. On top of that sit two brake drums and the flue/chimney.
Second pic is a close up of above. I chose to use what I had around and therefore used two clips to hold the pan on. Seems to work so far. Still fine tuning it but as I don't have a pyro to measure the temp I can't say how hot other than 'damn hot'!
Third pic is my crude oil feed device. An expired 4.5 kg gas cylinder with a hole in the top. I am replaceing this with a custom hopper of 1.6 mm prop plate thanks to pfillery:) which I will be able to attach a much better metering system as well.Maybe just an ordinary tap with restrictor?
Pic 4 Shows the total of emissions...so far it is cleaner than any wood stove I've owned. There is a slight odour though no worse than wood. Could be said that red gum smells better than castrol but thats in the nose of the beholder:D. Every bit just sits or slots together as it is real heavy. The 110 mm pipe is sectioned and what you see is the sleeve so that I can add sections.
Pic 5 shows it all. There is a section of flue pipe missing as I have big plans for this contraption. You are actually looking at the 2nd section of flue pipe, the first goes through a 44gal drum which sits atop the brake drums so the actual flue height is about 4" higher. Again the sleeves will allow me to add further sections of flue as I source them. Ideally lighter gauge rolled sheet rather than the 6mm wall stuff I have used for the bottom. Gunna try to use 100mm downpipe for the upper sections.:angel:
All in all, I am well pleased. I lit it this morning using a napkin sized piece of rag cloth with a cup roughly of waste oil poured in as well. Takes about 5-10min to stabilise and by using the bits of steel you see in pic two to control the early air flow, there was no smoke or fume at all!
What am I gunna use the 44gal drum for you ask? My plan is to use it to heat my pool! Tests at work revealed that it took 3 hours to heat the 44gal water to around 60-70deg. With a constant garden hose flow of about 15 lpm, no discernable drop in temp was apparent. I'll let you all know!
Ralph
