Simple mobile heater

Advice and help involving any mechanical issues.
native pepper
Posts: 1357
Joined: Mon Feb 23, 2015 8:21 am
Location: Tasmania
Has thanked: 5 times
Been thanked: 4 times

Simple mobile heater

Post by native pepper »

Keeping warm when on the road is something we all like, but when parked without the grid or the expense, horrible noise, smell and obnoxious pollution created by diesel heaters, decided to build our own little heater and see how it went in the bus after looking changing over a gas bottle and realising it would make a neat little heater.. Mentioned our little wood heater and was asked to start a thread about it. Had to make a number of posts as the site wouldn't handle any more than 3 photo's a post

Having returned To Tas from a chilly mid winter tour of Vic and NSW for our jazz season, decided we needed a heater as Devonport in July was particularly cold where we camped by the sea. Took a quick trip to the transfer station up the road from us and scored an old rusty 9kg bottle and a basket from a shop fridge. There were a number of gas bottles, but this one had been there for ages with the valve wide open and no gas smell emanating from it.

Removed the valve, flushed it with hot water and them cut the valve end of just before the tapper. Also cut off the bottle stand on the bottom.
heater construction1.jpeg
heater construction4.jpeg
Next welded a band of steel round the edge of the cut off so the valve piece fitted in between the steel band and bottle and welded the stand onto the side of the bottle for it to stand on.
heater construction7.jpeg
You do not have the required permissions to view the files attached to this post.
Last edited by native pepper on Fri Dec 16, 2016 9:51 am, edited 1 time in total.
User avatar
SteveW
Posts: 2343
Joined: Sun Dec 09, 2012 9:03 pm
Location: Glenelg, South Australia

Re: Simple mobile heater

Post by SteveW »

Sounds like an argument in favour of a diesel heater. :lol: :lol: :lol:
Steve Williams
http://stevew1945blog.com/

Every absurdity has a champion to defend it.
Oliver Goldsmith. 1728 -1774
native pepper
Posts: 1357
Joined: Mon Feb 23, 2015 8:21 am
Location: Tasmania
Has thanked: 5 times
Been thanked: 4 times

Re: Simple mobile heater

Post by native pepper »

Made up a strong hinge and cut a square hole in what was now the door and welded a little box with a slide door on it for air circulation. Cut a hole in the top near the rear of it and welded a bit of 2-5 inch exhaust pipe on it I had left over from installing an exhaust brake on the bus.
heater4.jpeg
Welded a couple of lugs into the bottle and cut down a grate from an BBQ obtained from the transfer station. The lit a fire in it to see how it worked and vented, which actually worked well and was drawing air nicely without any smoke coming out the front.
heater2.jpeg
Fixed it in an old commercial fridge basket for protection and ease of carrying and made sure the screws holding the heater the the basket came through, so they acted as anchors into the bus carpet. Put it in the bus and measured the chimney sections, which would be in pieces. Bought some 2.5 inch exhaust and got them to bend and flare one end of each section, welded handles on each bit with wood grips for safety, made a board to fit into the drivers window space and tried it out on a quick trip up the road where we camped over night in a snow storm. The heater worked so well, we were down to t-shirts and had to open a window to dispel the heat. The only problem was the fire went out pretty quickly when not tended to, so woke up the next morning freezing. It only took a couple of minutes once the fire was lit to warm the bus and it was back to t-shirt weather with snow on the ground outside and a gale blowing of the sea beside us.
heater6.JPG
When we came back home, threw out the grate in the heater and put in a solid plate so the embers wouldn't drop below the fire. From that point, the heater has functioned every winter for the last 5 years and is such a bonus to have. It uses little wood and one container of wood we carry, does us for a week.
You do not have the required permissions to view the files attached to this post.
native pepper
Posts: 1357
Joined: Mon Feb 23, 2015 8:21 am
Location: Tasmania
Has thanked: 5 times
Been thanked: 4 times

Re: Simple mobile heater

Post by native pepper »

As for using whilst travelling, have done that at a couple of festivals when moving between venues and back and forth from where we camp. But it means the driver has the chimney going over their heads and doubt the cops would appreciate that on a highway. It could be installed so you can use it when driving. The bus heaters work well enough for on the road to not need it and when we stop, the heater works well enough so the bus doesn't cool down between the two forms of heating. In the morning I warm up the bus and when the heaters are working, take out the wood heater. It takes a couple of minutes to set up and pull down. Total cost was less then $50 for the exhaust pipe and bending, everything else was recycled, as is just about everything I build, even the house extension I'm currently doing is all recycled. The framing is reject pine framing which is warped and bent, cost $1 a metre and makes for a good challenge to get things square and level.
heaterr7.JPG
Now the heater has proved itself over the years, it's about to get a paint job with heat resistant paint for next winter and have a number of different size gas bottle sitting around with valves remove ready to be made into heaters. One for the workshop and another big one for the drummers house, my place has a wood stove so has no need for an extra heater.

It all pulls apart and stores in the boot of the bus, along with a crate of wood.
heater kit.JPG
heater wood.JPG
You do not have the required permissions to view the files attached to this post.
Last edited by native pepper on Fri Dec 16, 2016 11:19 am, edited 1 time in total.
User avatar
Dot
Posts: 24720
Joined: Fri Nov 23, 2012 6:12 pm
Location: Strathalbyn SA
Been thanked: 37 times

Re: Simple mobile heater

Post by Dot »

Looks like a goer to me.
Queen of the Banal & OT chatter and proud of it. If it offends you then tough titty titty bang bang.
User avatar
Dot
Posts: 24720
Joined: Fri Nov 23, 2012 6:12 pm
Location: Strathalbyn SA
Been thanked: 37 times

Re: Simple mobile heater

Post by Dot »

NP what is the set up for the chimney through the roof when you dismantle the fire?
Queen of the Banal & OT chatter and proud of it. If it offends you then tough titty titty bang bang.
User avatar
T1 Terry
Posts: 15963
Joined: Fri Nov 23, 2012 3:44 pm
Location: Mannum South Australia by the beautiful Murray River
Has thanked: 50 times
Been thanked: 30 times

Re: Simple mobile heater

Post by T1 Terry »

The flat plate, what is the swan neck piece for? Also, where the gas valve was appears to have a stopper with 4 steel legs welded around it, what it the purpose of that? Wouldn't a bung plug have sealed the hole well enough? Not criticisms, love the idea, just a bit of clarification that's all.
I have a number of old auto gas tanks I've be looking at making into wood fired heaters and looking at different designs to see which would work better. Any reason for making the cyl lay down rather than stand up?

T1 Terry
A person may fail many times, they only become a failure when they blame someone else John Burrows
Those who struggle to become a leader, rarely know a clear direction forward for anyone but themselves
native pepper
Posts: 1357
Joined: Mon Feb 23, 2015 8:21 am
Location: Tasmania
Has thanked: 5 times
Been thanked: 4 times

Re: Simple mobile heater

Post by native pepper »

That's ok cobber, it's posted for questions and happy to reply. I tend to be a bit unorthodox in my approach and doing things, which always brings lots of questions. So considering my engineering abilities, whatever I make has to have tolerances. I experimented and changed things until I got it the way I wanted and under all conditions it worked. This is the second one I made, after making one which looked like a normal heater with a hinged door and sitting upright, classed it as a failure. These tanks are not designed to be heated from the inside, to thin a material so they expand and warp a bit.

The swan neck is so the door opens and swings away, because of the heat, the hinges you can buy and a couple of crude heavy ones I made, tend to bend and buckle under the weight and heat, so scraped that. This way you over come the problem and as it is round, you overcome the change in size and shape they tend to become once heated. The first one had the flange/flare on the door and when heated, was almost impossible to shut over the heater body and getting the right tolerances, was going to take time and I'm lazy, so took the easy way out.

Again because of heat, sitting the door shut when hot is different to when cold and the flange it fits into becomes difficult to get into, but much easier than having the flange on the door. So the door floats between the 4 stays and also on the hinge arm, when you shut it cold, you need to wiggle it a bit, when you shut it hot, it goes straight in. So having it float around a bit, means it can be jiggled into place easily and you don't have to touch any hot bits as the handle on the door lock acts like a guide.

The first one was upright, which really restricted the length of wood you could put in and as you only need a couple of pieces, its works fine this way. Having it upright meant shorter wood, stacking wood into it meant a bigger door and you had to keep putting wood in, which was short and bulky. Plus i found with the extra air space inside, wood tended to burn faster and couldn't be bothered putting in a restricting roof, as that would buckle in the end. Now we just throw in a couple of cut up branches, warm the bus and leave it for a an hour or before needing to refill it. Putting in 3 pieces of wood means it will smoulder until morning and then you can open it and add wood. to really warm the bus.

I'm sure it can be improved on greatly, but it has worked for years, not burnt out as other uprights I've seen and looks like lasting a long time. Lying down means it is low, stable and the hot areas are low, except for the exhaust stack which really contributes to warming because all the heat is dispersed into the bus and the outside bit has little heat to lose. Plus it doesn't take up a lot of room in the boot, whilst one standing up takes more room.
BernieQ2
Posts: 8257
Joined: Thu May 07, 2020 7:57 pm
Has thanked: 13 times
Been thanked: 25 times

Re: Simple mobile heater

Post by BernieQ2 »

Cool ,sorry for the pun .
Bernie .
User avatar
Greynomad
Posts: 9025
Joined: Tue Dec 04, 2012 4:16 pm
Location: Rutherglen, Vic.
Has thanked: 28 times
Been thanked: 61 times

Re: Simple mobile heater

Post by Greynomad »

Looks like a great piece of home engineering, but I question the safety of having what amounts to an OPEN FIRE inside the m/h.
We have a similarly-engineered slow-cooker/brazier made from a 9kg gas bottle by a Tasmanian we met on our mainland travels some years ago.
However his design uses the bottle vertically, with a lift-off top made from the cut top of the bottle (collar removed), held in place by a strap similar to your system.
The valve has been removed and the hole enlarged to take a 2" (dia) x 4" length of Holden tailshaft tubing fitted with a home-made butterfly valve to regulate intensity of burn. Air inlet is via a ring of 1/2" holes around the base just above the stand ring.
Sides are drilled to take two v. large tent-pegs, which are the stand upon which a 4 1/2 quart dutch oven sits neatly... about 1/2" clearance all round for heat circulation. A side door has been cut to tend the fire.
Works brilliantly as an outdoor oven. We can cook a full roast leg of lamb over 3~4 hours using a handful of kindling & six heat beads.
The only thing missing is a couple of handles on the outside to carry it. We use the bent ends of the tent-pegs, but welded-on handles would be easier...
As a brazier, it's similarly efficient. We can use 1ft logs, as they can poke up into the 'cooking chamber'.
It came with a steel table with angle-iron legs, which, when inverted makes a very snug carry-box. Fits our under-floor bins beautifully.

We also have a smaller brazier made from a 4.5kg gas bottle. Bought at Casino many moons ago. It has the top cut off (collar retained), which is used as a stand to keep the radiant heat from scorching the grass. A triangle of 1/2" holes in opposing sides let the air in, and their positioning determines the intensity of the flame. Place it with the holes in the windward/lee position for maximum heat; turn them 90 degrees (blank sides to windward/lee) for a lower flame. Simple! It has a couple of bars welded across the top to take an iron frypan (which fits beautifully), and they are slightly offset so you can store the lid upside-down in it with the collar neatly fitting in the offset, which centres the lid over the belly of the bottle. Clever, that.

The smaller unit has been relegated to home use as a brazier in our ODLA since we bought the 9kg unit... don't need to carry TWO braziers! ;)
Regards & God bless,
Ray
--
"Insufficient data for a meaningful answer."
Isaac Asimov, "The Last Question"

"I refuse to drink water, because of the disgusting things fish do in it"
W.C.Fields

Return to “Mechanical ... Nuts & Bolts”