thomas rubino

Hi John;
Good question!  
I'm not sure if draining a lead acid is proper or not.
A quick look showed them removing the sealed top to add battery acid.
Hopefully, another will reply who has tried this.

To drain a 12 vt mini battery I would hook a 12 vt automotive light bulb directly to the battery.

Hi Holly;
Mike is correct that it will be rather cold in the morning anywhere but sleeping/ sitting on the mass.
After all, a Tipi or Yurt, or any glamping tent is still just a tent.
Hop out of bed and fire up the J-Tube and it will become warm in short order.

I suggest that rather than a tent you consider a small stick-framed house that can be insulated.
Here is why,  Unheated tents are subject to mold, rodents, and other incidents.
Yes, while building your home it would be nice.  However, once it sits empty and unheated...  things happen.

Around here there are smaller uninsulated buildings for sale with free delivery.
They are called sheds and some are simple sheds but most are tiny homes with no wiring, plumbing, or insulation.
The costs are reasonable considering it is delivered and ready to sleep in the day it arrives.

As a possible B&B after you move into your new home it would remain clean and tight compared to any of the tent-style structures.

Hi Yasmi;
Erica & Ernie built J-Tubes with a piped mass.
Batch boxes rarely utilize a piped mass but instead, more commonly use a stratification chamber (bell).
With a piped mass you want your J built to specifications, and you need a large smooth transition area where you enter the pipe system.

With a stratification chamber, things become easier.  
There is still a CSA for bell size that should be followed although, using a bypass that can be exceeded.
Your core, be it a J-Tube or a batch box needs to be built to specifications, any little changes can affect rocket performance dramatically.
Once the super-heated air leaves the riser and enters the bell, it has no choice but to rise to the top. After arriving at the top it is instantly replaced by even hotter air.  The cooler air sinks lower as the hotter air replaces it at the top.  At the bottom of your bell is the outlet chimney.  The still-hot air discovers this pipe and starts rising again(after all it's the hottest air in that pipe) this starts the draft going.

So, If building a J-Tube with a piped mass then all parameters must be strictly followed to get a successful build.
A J-Tube can be built using a stratification chamber rather than a piped mass.
Here is my shop stove as an 8" J-Tube into a brick bell.   https://permies.com/t/94980/Brick-Bell-Shop-Heater
https://permies.com/t/99519/Baby-Dragon-Roars
This design worked great until I decided I wanted to build my first batch box.
And here is where I changed it to a batch box.  https://permies.com/t/138779/Breaking-News-Shop-Dragon-admitted
And here is the latest configuration of The Shop Dragon  https://permies.com/t/181421/Batch-box-rebuild
https://permies.com/t/190599/Finishing-touches-Shop-Dragon-rebuild

And this year's winner of the Lazy cat award!

Hi William;
Yes, both the 6" and the 7" batch boxes are built to Peter's dimensions.
The 8" J-tube in our studio utilized an 8" piped mass.
A 6" batch box is the largest size suggested to use with a piped mass.
That stove is problematic starting in the fall.
It has a tremendous mass that must become warm before a strong draft starts.
Use of my bypass is mandatory until warm.

The 8" J-Tube in the shop only had a single barrel.
After converting it to a stock size 7" batch.
I added a second barrel to increase my overall CSA and to provide instant radiant heat for a large practically uninsulated shop.
The brick bell has two tall towers of brick inside, as well as a few chunks of railroad track leaning in a corner as extra mass.
Once that bell warms up to 200-300F external temp. the entire shop becomes warm.
Open the shop doors to bring in equipment and it only takes a few minutes for the entire shop to feel warm again after shutting them.
Prior to having a brick bell RMH, I had a double-barrel conventional wood stove.
It could be glowing orange and you could not get closer than 5 feet from it.
15' away tools would stick to your fingers it was so cold.
Open the shop doors and it never warmed up at all.

Building RMHs was the best idea I ever had!
Converting those stoves to batch boxes was the second best!

Hi Steven;
Oh boy, do I feel your pain.
So, until the '90s this house used a well.
The connection from the city water sounds like a funky homeowner install.
PVC pipe was common in the 90s, and any plumber would have used it.
If you can fix it, great, I really hope so!  
I suspect that there are threaded connections inside the basement, if so you should be able to attach to it.  

Be aware that they can drill horizontally these days.
I'm sure the cost is scary, but it's a better option than removing the dining room floor and hand-digging that pipe out.

Hi Blake;
I looked and there do not seem to be any specific pictures of that model.
I would call it a parlor stove.   Yours looks to be wood only, as many were dual use wood/coal.
The crack running across the bottom does not look good at all.
That could be why this stove was removed from service.

Hi Scott;
I think that a home-built inline butterfly damper with no extra holes would do the job.
A guy handy with a welder could fab one up... Know anyone like that near your house?
My blast gates are fast and easy for folks who do not have a welder.

Hi Allen;
As you are wanting to heat a shop here is a rebuild on my 7" batch box shop stove.
Double barrels for instant radiant heat and a large brick bell to hold that heat when the shop doors are opened to move equipment.
https://permies.com/t/181421/Batch-box-rebuild

Hi William;
Here is my conversion from an 8" J-tube to a 7" batch box in my shop
And here is my 8" J-Tube being converted to a 6" batch box
https://permies.com/t/138779/Breaking-News-Shop-Dragon-admitted
https://permies.com/t/148226/Dragon-Transformation-tube-Batch-Box

Fuel consumption is very close between the two styles.
An 8" J-tube requires feeding every 45-60 minutes.
A batch box requires wood every 2-3 hours.

Batch boxes cost more to build by at least a few hundred dollars depending on, creating your own metal parts or purchasing them from me.
Both styles are simple to build, J-Tubes require no metal parts in the core.
If you are a perfectionist then your RMH will work flawlessly for years.
If you are like the rest of us then you will be making changes /improvements or even repairs, from time to time.
Don't sweat about it. Once you build your RMH you will understand just how simple and easy it really is.
Rebuilds and changes are just a few hours of work no big deal.
I have done emergency rebuilds during the middle of winter. They go fast when working with clay/ sand mortar.
If you feel the need to build using overpriced refractory cement then all bets are off!
Rebuilding with refractory involved is a nightmare!
I highly recommend 3 parts clean sand to one part clay as mortar

Size?  J-tubes are commonly  6" or 8"
Batch boxes can be as small as 4" or as oversized as you care to create.     6", 7", or 8" are the common build sizes.