Rocket Hot Tub Project

Well, i started working on my hot tub heater. im terrible at descriptions and i dont have much skill at paint programs, so i made a video:

http://www.youtube.com/watch?feature=player_detailpage&v=Pd1xWWyDSSs

this is an after work project, it may take a while. ill keep posting updates as i go. so far i have the heat riser and feed tube fabricated and tack welded, as soon as i get a couple of pieces of chimney i can test fire that portion of the design. the heat exchanger will be a bit of a challenge to make, but not too bad i think. cheers. jaime.

Good for you! I think you have something functional in the works. I'll be watching, look for you to post your progress.

At the lower ranch we have a hot tub, electric, we use it in the summer to cool off but the water gets very cold.[Do not want to heat tub with electric] Don't mind having the pump on for the filter, but plan to make a wood fired heater for it. This could be just the ticket.

What you have so far shows some craftmanship.

here is an update on the progress so far. ive actually got as far as tack welding the whole system together (minus the heater core), ill have video of that soon. the heater core will be a bit challenging to put together, lots of holes to drill and lots of welding with no leaks allowed.
http://www.youtube.com/watch?feature=player_detailpage&v=fJSMuV2oawA

Well Jaime, That looks pretty good. I could see the cunks and chips coming down into the firebox. Looks good so far, the heat exchanger will be a challenge, your planing to do without a pump or you can use the filter pump. Very good luck to you, bless your hands.

I bought a wirefeed a while back, it'll take a little prictice to weld that light metal you're working with. Thanks for the update.

thanks. yeah, sheet metal is a bear to weld with the wire feed. i just hope that by the time i get to welding the components for the heat exchanger ive got enough practice to make a watertight weld.

as to your current design i wouold be concerned with your wood chips preventing the ifre from getting enough oxygen, to prevent this i would say to have metal "sticks" in your burn chamber to keep the chips seperated enough for oxygen flow, if that makes any sense
i just think if you don't you'll end up with a smoldering pile and nothing else...

with water also making a very effecient thermal mass i think a hot tub may increase the effeciency of your RMH
this next part i dont think applies directly to you because it looks like you're simply heating the water before it goes in but i was thinking

im kinda new to the idea but it seems fairly simple to me so i would think you coud run the ducting for the exhaust under the seats in the hot tub, and maybe along the back rests, thereby using the walls and seats as your thermal mass and heating the water as well, besides the benefits of making water youre thermal mass i think that by making your own you could get a really neat looking hot tub that LOOKS really high end and expensive and by doing that you would add property value to the home it was in...

He has arranged a grate.

i did see the grate i just figured it may not be enough on its own- that doesnt mean im right though i have no first hand experience with the matter really, at least not a lot
the feed tube is an ingenious idea though...

the grate as i have it now will not work for chips. im going to focus on getting the components assembled and tested, and then i will experiment with grate configurations. it is certainly doable, but everything else has to be in place first.

the progress so far... http://www.youtube.com/watch?v=wHeegB1PMfA&feature=player_detailpage

Cool project!

I found this yesterday while wasting time on the web. While it's not a rocket heater I still think it's pretty damn cool. I am envisioning and army of these little gremlin guys "gaurding" my food forest.

http://www.instructables.com/id/How-to-build-a-wood-fired-hot-tub/step15/Fill-the-tub-and-light-it-up/

Ya, love that one. Its one of the projects that inspired me to try my hand at making a backyard tub of my own.