Craig Tupper

Chris Vee wrote:We are interested in the 240mm ID x 416mm long riser tube(s)— I haven’t done enough research to know what all we will be needing but I know we will be installing our RMH before the next winter and we’re looking to create a rather large system. Is this purchase still in the works?

We are in SC & will happily pay any shipping charges necessary.

Thank you!

Hi Chris,

It turns out you are the first person to express interest, either here or on the proboards.com site. I'm a little surprised by that, but it is what it is.

I've since learned that shipping costs from Belgium would approximately triple the price of these tubes, assuming I bought them in lots of 20. In other words, I would have to lay out around $4,000 to have 20 tubes delivered. That might still make sense, if there were enough buyers here in the US lined up, but not if you and me are the only ones. There's a chance I might still do it some day, if my son decides to make a business out of building stoves. But that decision is at least a year off.

Would you be interested in a vacuum-formed ceramic fiber tube from Danser in WV? I don't have a quote from them but I'm guessing $400-500 per tube if we bought 2. https://danserinc.com/capabilities-vacuduct/

Craig

John C Daley wrote:These fireboxs seem different from Rocket Mass Heaters, is this correct?

I would call the DSR3 a rocket stove, Peter van den Berg does (it is on his batchrocket.eu site) but I haven't been around here long enough to argue any fine points.

There are two basic options after the core:

1) surround the core with thermal mass for the capture and slow release of the heat generated. That could just be a brick/block bell, or could include a bench.

2) minimize the thermal mass, in favor of metal bell(s) that will radiate the heat quickly.

You can also design something in between - a small metal bell on top of some thermal mass. The choice comes down to whether you want steady temperatures in a place you will be in regularly (go for the mass), or you want a fast response to heat a space you aren't in all the time (avoid the mass). I think this is true for anything that burns wood.

John C Daley wrote:Are photos available for those who dont know anything?

You should familiarize yourself with the DSR3 design.

Early DSR1,2 development story from 2017-2021, in a nutshell: https://batchrocket.eu/en/designs#dsr

This thread, page 7, post dated 2/3,21, includes a pic of the first DSR3 test model tube:  https://donkey32.proboards.com/thread/3710/dsr1-vortex-aspects-dsr3?page=7

There is also a lot of discussion, and "final" DSR3 core dimensions, discussed here: https://permies.com/t/192518/Planning-DSR-Build-Cooktop-Questions

SketchUp drawings and more pics are downloadable from those threads.

I've received a quote from Belgium for pallets of 10 afterburners, of the same type being used by the Loam Freemanship, who have worked with Peter van den Berg.

Sizes and prices (without shipping) were quoted as follows:

177mm ID x 305mm long, 30 mm thickness (approx. 7x12x1.2", good for a 6" system), 10 for 663 euros or about $71 each

240mm ID x 416mm long, 30 mm thickness (approx. 9.4x16.3x1.2", good for an 8" system), 10 for 838 euros or about $90 each.

I am looking into what it will take to get them delivered to my address near Reading PA. From there I could potentially ship them individually to others in the US, or hold them for pickup. I would provide them to you at my cost, I'm not looking to make a profit. Even if shipping triples the price to you, it still beats the best quote anyone has reported from a US provider for vacuum-formed ceramic fiber tubes. And these tubes have a track record in Europe, with clay mixed in for added structural integrity, which as far as I know the US suppliers are not offering.

Please let me know what size and quantity you are interested in.

Also, if anyone has any pointers on arranging shipping across the pond, please let me know.

Hello April, and other US-based permies,

I've received a quote from Belgium for pallets of 10 afterburners, of the same type being used by the Loam Freemanship, who have worked with Peter van den Berg.

Sizes and prices (without shipping) were quoted as follows:

177mm ID x 305mm long, 30 mm thickness (approx. 7x12x1.2", good for a 6" system), 10 for 663 euros or about $71 each

240mm ID x 416mm long, 30 mm thickness (approx. 9.4x16.3x1.2", good for an 8" system), 10 for 838 euros or about $90 each.

I am looking into what it will take to get them delivered to my address near Reading PA. From there I could potentially ship them individually to others in the US, or hold them for pickup. I would provide them to you at my cost, I'm not looking to make a profit. Even if shipping triples the price to you, it still beats the best quote anyone has got from a US provider for vacuum-formed ceramic fiber tubes. And these tubes have a track record in Europe, with clay mixed in for added structural integrity, which as far as I know the US suppliers are not offering.

Please let me know what size and quantity you are interested in.

Also, if anyone has any pointers on arranging shipping across the pond, please let me know.

I'm going to create a new thread for this as I'm guessing there may be wider interest.

Hi Matthew,

I recently asked the same question and Peter van den Berg replied that you shouldn't build larger than your flue size. That answer can also be found deep in the archives on the Experimenter's Corner site. Of course putting in a larger flue may be possible, albeit expensive. Good luck with your build.

Craig

Solomon,

Thank you so much for all the extended documentation. I'm still early in planning my first rocket, and your experience is extremely helpful.

The 2x4 house I'll be heating is similar to yours in size. I'd like to make sure I understand your wood usage experience. If I understand correctly, using your 7.5" J-channel rocket you have heated your house in Oregon with about 1/6 cord every 10 days... or a cord ~ every 2 months... maybe 2+ cords per winter? That would be very encouraging to me.

Sorry to hear about your riser melt. I'm planning a DSR3, partly because that design seems resistant to runaway.

In case you haven't seen it before, thought you might find this resource helpful. It suggests that your "melt" is actually an accelerating process that may ultimately crumble your riser if unchecked... which could be bad  https://donkey32.proboards.com/thread/3909/firebricks-refractories-fail-silica-flux  

Best wishes,

Craig

I have three half-baked ideas. Maybe tenth-baked.

The first was to circle back with either Ceramaterials or Danser, and ask what they would charge for a bulk order of 6" and 8" tubes. I want an 8"  It seems like there is enough interest/frustration/demand here and at proboards that we might be able to divvy up at least 5, maybe 10 at a time of each size, at a price that doesn't make people choke. I was thinking of taking a poll on interest. Shipping could be an issue, IDK, but if that were solvable I could buy the bulk order and then distribute. I'd probably give you a big discount in thanks for all your efforts, and charge a little extra to everyone else.

My second idea was to ask why we can't get the European supplier to ship here. Too fragile, import issues, price too high?

My third idea is to throw in the towel on CFB and learn how to make refractory castings. Maybe start a business for my son.

Anyway, hope I'm not wasting your time here, and good luck with your project.

April, your contributions on this subject are amazing. Do you have any results yet from your attempts at building an afterburner? I hope you haven't given up, would be great if you have succeeded, but if not I have an idea for procuring them that I could float. Craig