Marco Guerrini

Hello!
The footprint is roughly 600mm x 1000mm.
The lid can be removed for pizza mode, add the lid for smoking/cooking meat on the top (grill mode).
The design is based on a J-tube style rocket stove. Sticks standing vertically in the oblong wood feed.
I think I would try to get the middle up to temperature, then put a pizza inside, probably nearer the heat riser.
Yes, 18" tall terracotta chimney pot from the builder depot. That's the bit that holds me back from revving it too much. I could do bricks all the way up, but I've bought the chimney already.
I'm hoping I can get away with it. So far its survived 2 sessions.
The gap between the top of the chimney and the edge of the top kettle at the final exit point (where the mushroom gills would be) has a cross sectional area similar to the rest of the J-tube path (more so in real life than the screenshot), I hope that prevents a bottle neck.
So far it seems to draw strongly/reliably in the correct direction (in a previous version with smaller general cross-sections), making a satisfying grumbling noise.

Hi Permies,
I'm new to rocket stuff. I bought some fire bricks, had a play, and now I intend to assemble this rocket oven design.

I cut the bottom off a standard kettle bbq to create a mushroom shaped grilling chamber.
Chimney pot for second half of heat riser.
The side has 3 removable bricks (with gaps by the edges), to form a door.
Pizza stones on the bottom.
1000x600x25mm Vermiculite board to span the ceiling.

The picture should explain better words.
Suggestions please!
Thanks

Building your own microhydro or picohydro system sounds like great fun.

I have no idea about costs, but there will be a lot of factors:
What does the source/terrain look like?
How much horizontal distance do you have to travel to achieve your 50ft of head?
Are you taking water out of a stream and putting it back in the same stream? Are there fish?

With a small house 5kW continuously may be enough, maybe 10kW for a large house. So I think you will need batteries or other energy storage if you are not connecting to a grid.
Energy from a raised mass = mass x gravity x height.
Power = Energy/time = mgh/time  = g x h x (m/t) = gravity x height x mass flow rate
h=17m, g=9.81, m/t=75gpm=5.7kg/s
So at 100% efficiency = 9.81*17*5.7=951W to play with
This may change seasonally.

You can use a turbine selection chart to help you pick an appropriate turbine based on head and flow rate for your site, but there are also other factors

I once designed a turgo turbine system with some other guys at university. It had a pipe taking water into a channel.
The channel then widened to slow the water down, through big filters and then small filters + sedimentation.
Then the pipe which dropped in height shot the water through a nozzle at a turgo turbine.
Then the water went back to the stream.

Pumps can also be run in reverse to act as a generator.
There must be lots of cool arrangements of ponds at different heights where you can use a pump when you have spare energy, and use the same pump to extract energy when you need it.
Eg. Please see attached for an idea.

Possibly an epic jump from the toad? how big are these toads?

With the beds running east-west, i want to keep the bordering edges closed so the grass from the communal paths (running north-south) does not invade and is easily strimmed.

This would make each bed a long dead end. Do you think this would reduce throughput of the predators?

Maybe hedgehogs could climb copper mesh nailed to the sides of the bed but not snails and slugs.

Hello,

I would like to convert all my allotment beds into raised beds, but I worry I will create a barrier for helpful predators.

My allotment plot is in London, with slugs and snails decimating young seedlings in the Spring.

I already have slow worms in my compost heap, and I've seen what I believe is their skin on my beds, so I've stopped using slug pellets.

In the long term i plan to install ponds and hedgehog houses to get all these guys to patrol my plot so I won't need pellets.

...But, how can I help them access the raised beds without taking up valuable room with ramps etc...

Any ideas would be much appreciated! Thanks.

At the moment I'm considering raised beds with missing portions eg. [ ]