Mega cool I have to say.
Yes sticking pellets are no good. I haven't heard about the Wiseway having an issue but they are insistent on using quality pellets. That may be a large part of trick. If you want to burn rubbish then maybe gravity feed is not the way to go.
Do you think there is a correlation between stove temp and sticking? ie do you have more problems if the stove is hotter?.
I'm pretty sure m issue is more the way it feeds than heat or anything else. With premium pellets (pine or hardwood...or actually ANY pellets) the issue comes from stupidity on my part. I should have fed it straight down and not trying to get gravity to make an exception for me. Also, the tube feeding constricts somewhat, going from 2.5" to about 2.4" at the bottom (the nature of using car exhaust pipe fittings). New one will go from 2" or 2.5" at the top to 3.0" at the bottom, and it'll work WITH gravity this time. (Gravity: It's not just a good idea, it's the LAW!) I think it's just a matter of making sure things don't get smaller.
Heat can be an issue, but it seems to be only if it's already getting tight in the tube. I think that is taken care of with this next one. BUT, you can only mitigate heat to a point when your feed tube ends || this far above the fire. There's also a bit of fresh air coming through the pellets into the tube into the firebox. That keeps it cooler than the reverse and the air coming back up from the bottom
Some type of sleeve, or something like a dielectric to prevent or reduce heat transfer between the feed tube and the combustion area....hmmm....I think I might have that idea running around in my head. Hmmm.... I think I got that covered now
You are dealing with so many variables at the same time that getting ideal performance is a real big ask..
The American phrase of "No $h!t" comes to mind
While I expected that everyone goes through this when starting from scratch, I'd hoped I'd learned a bit seeing how others have done theirs. But, as with anything 'new', there are bugs. If you can fix the bugs, things work. If not, or if you don't want to, you get another lawn ornament or another trip to the scrap yard. While being in WV, lawn ornaments are OK, but only if it's a used appliance or an old car with the wheels off. This would almost be considered 'art'...and some folks would think I'm uppity....and I'm kinda scared of banjo's. (see the movie Deliverance if you're unsure of the comparison!)
LOL!
As I see it getting the fuel supply and burn system right are the most important and it sounds like you are getting there. Keeping the heat exchanger tubes clean is also very important and it sounds like you are onto that as well..
I think the original 2" was just too small, also getting the burn right. Bad burn/unknown 'ratio' = too much smoke = too much soot = clogged pipes. They can be cleaned with a long bottle brush (from amazon.com) but being able to get the regular stove brush into them will be much nicer. Original one used round holes cut into the large tubes, and the cross tubes welded over them. A 2" holesaw doesn't account for the corners, and I didn't file or grind them out. (hell, I didn't think it would even work when I first started) The new one has full sized square holes cut into them. Instead of 'corners' (round tube/square hole), it's pretty close fit. Should assist with both airflow and ash/soot removal. Especially the use of 3" cross tubes.
Minimum combustion air flow is important as you describe. This also reduces particulate matter which is a problem (i think) with the Wiseway but could be addressed. The downside is that crud will build up quicker in the tubes which is why easy cleaning is so important..
'zactly. A fan would really assist the combustion, but that kinda defeats the purpose. I'm hoping more, or at least better airflow, through it will help in all regards.
You and I have very different heating requirements so I would see 44lbs as the maximum anyone would want to burn here. 30lbs is a average 24hr run for us so you are well in the range we want. I think using heat recovery from the flue would improve efficiency further but that is not an issue at this point..
We've seen -20F through 115F here in the past 14yrs I've been in WV. I've seen snow that only the top few feet of the telephone poles stuck out of, to winters with little/no snowfall and more above freezing days than below freezing. While it will be completely dependent on how much heat the owner wants, there will still be variables in how fast it wants to feed. Fast burning pellet = less heat = more used to get it warm and the inverse as well. Throw in a correct or incorrect installation, cross winds, humidity, pressures....ballpark is all we'll ever get. I'm sure manufacturers have been 'bothered' by folks asking those questions since the beginning of time: "Why doesn't my stove do
"exactly" what you said it would do?" Yeah....I love those kinda people too!
From a construction point of view I would be using mig in a jig with either the robot or by hand so easy layout will eventually be important. If the stove has separate parts it makes manufacturing much easier. You dont need to worry about that. I can adapt the successful design for mass production. I am not concerned that your hopper won't hold 2 bags. Most of our customers pour their fuel into buckets then into the hopper. Height and ease of access is most important, even 1 bag is enough..
Using all 'stock' materials will help greatly, since they're the easiest to acquire. I hate having to special order anything. Having someone build your hoppers (just a can with a slope towards the hole) to your spec will be a simple matter. Building a jig for this will be easy as it's all right angles. I cut all the materials (and most holes) using a plasma cutter and a speed square.
http://www.amazon.com/Swanson-SO101-7-inch-Speed-Square/dp/B00002255O/ The use of a CNC would only be needed for the burn chamber, and only if you didn't want to clean up after a plasma is done. (oh, and the cool factor of having a CNC in your garage
)
I am really interested in the concept and we will have the fuel supply (from a large new mill in Australia) by mid year so I see great potential for a gravity stove in 2016 in Australia. I would be most interested in seeing pics or rough sketches of your ideas and want to work with you on this. Please contact me directly.
Great. Seems the market is slowly filling in the blanks in a wide open market. Is there much of a market for pellet stoves, or is it more/still wood/biomass? We can get the whole email chain started, maybe a file share site to make it easier to pass documents back and forth. While I'm partially a computer guy, I'm mostly a hands on, shake hands, hold this wrench kinda guy. You might have other ideas, and since you're paying
, I'll let you tell me what you need to see.
I cannot come over now because we are about to move into heating season but could visit in October onwards. My wife is going to LA in November but she would kill me if I sent her to see a stove! One of my manufacturing associates is in the US regularly and I could send him to see you if we can get things moving. Lets make a date.
Will do. I'm sure we can come up with something. Let me prove this next one works, and we'll set something up. Even in WV we have Skype (what I was using to talk to my brother in Tazzie, when he's not on the ice) We'll work something out.
And for everyone else, I'll keep updating here as long as it won't cause issuees between Chickenman and myself if we enter into some type of agreement. I'm usually a 'here it is, anyone can build one' post it all and let you go from there. But that might become an issue in the future.
I'll be in the shop. I have a few things to work out.
