What material for a DIY tent stove flue?

[kard133]

I am thinking about making a cheap little tent stove from some Gastronorm pans, and I am unsure of what to use for a low cost flue, and would welcome some advice from those who have made them before. Some of the options I have seen include:

Mild Steel car exhaust pipe.
Galvanised spiral ducting (I think the galv would have to be burned off, or would burn off during use, which I think can be quite toxic)
Shim steel, but no how to guide mentions the thickness.
Stacked food cans (seems very labour intensive, and not very gas tight.
Rolled up baking sheets (thin gauge metal from poundland and similar)

If anybody has any suggestions, hopefully under the £25 mark and available in the UK I would be very grateful.
Also any advice on choosing flue diameter, length etc?

 

[swyn]

I am thinking about making a cheap little tent stove from some Gastronorm pans, and I am unsure of what to use for a low cost flue, and would welcome some advice from those who have made them before. Some of the options I have seen include:

Mild Steel car exhaust pipe.
Galvanised spiral ducting (I think the galv would have to be burned off, or would burn off during use, which I think can be quite toxic)
Shim steel, but no how to guide mentions the thickness.
Stacked food cans (seems very labour intensive, and not very gas tight.
Rolled up baking sheets (thin gauge metal from poundland and similar)

If anybody has any suggestions, hopefully under the £25 mark and available in the UK I would be very grateful.
Also any advice on choosing flue diameter, length etc?

I used vacuum cleaner pipe for my comet. This was about 1 1/4” diameter old money.
S

 

[gra_farmer]

Most metal pipes will work, but as you correctly stated, stay away from galvanised pipes. I was also told a while ago not to use chrome plated pipes for the same use but cannot remember why, possibly the same as the galvanised?

Mild steel box section is brilliant for your use and often available as scrap

 

[bopdude]

The titanium roll up chim6 pipe can be bought seperate at a good price

 

[FerlasDave]

I tried the stacked food cans before I knew better. If it was now I’d use car exhaust repair sections, they’re not too expensive on eBay. I’d find someone who can weld half decent and get a good connection to the top though, I always found that to be the hardest part.

 

[nigelp]

150mm rolled shim steel - 2.5 metres should work ok?

https://www.mscdirect.co.uk/PBS-16978A/SEARCH:CATEGORY/product.html

 

[kard133]

Thanks for the suggestions so far.

 

[Danceswithhelicopters]

Have a look at Aliexpress. Everything there comes under your budget from rollaway Ti to SS sectional pipes with bends and connectors. I'd be loathe to use jerry built options due to the risks of CO and leaks in a tent.

 

[FerlasDave]

I’d be more concerned with leaks from catering pans than an ammo box, you can replace the seals with stove rope to prevent co2 escaping.

I’ve been thinking about an ammo can design myself for a while now, I’ve done a few in the past but would like something robust. I’ll try and dig out the old threads on here. Since brexit the cheap Chinese ones seem to have gone off ebay too so would probably be cheaper to do a diy one again.

 

[demographic]

Getting this wrong means ending up dead, stacked food cans is Stig Of The Dump type stuff. Its possible but too easy to feck up and gas yourself. You won't know but your family will be gutted. Please avoid.

 

[kard133]

I have looked on Aliexpress, so far there is nothing within my total budget that I can find, especially when you factor in VAT, shipping and that nearly everything has an estimated delivery date of March, so no way in time for the Wintermoot.
My understanding of wood stoves, especially portable camping type ones, is that they are not airtight, the heat from the fire/coals creates a negative pressure where the hot exhaust gasses are drawn up the flue and air is sucked in from the inlets and any unsealed seams. Since I use a floorless shelter, and would ensure that there was adequate ventilation, this should minimise the CO2 risk.
I think I may end up using some mild steel tube between 70-80mm in diameter, 1.5mm wall thickness.
Thanks for all the suggestions.

 

[huntersforge]

Been using 3 large dog food tins riveted together on my tent stove now for about 6 years and it’s still going strong. Firstly on my frontier stove and now on my latest winnerwell.

 

[TLM]

70mm dia sounds about right but 1.5mm thickness is ecxessive I think. The ones we had in the army were about 0.8-1mm, they could and did get beat up. It really depends how hot you intend to use the stove, if red hot 1.2mm might be required to prevent buckling of the pipe. If less than red the thinner ones will serve ok.

 

[FerlasDave]

Just remember that lack of air tightness is a double edged sword, yes it will ensure the chimney effect pulls gasses away but in the event of a flue fire you can’t choke the fire enough to put it out. Obviously I think the solution is not to have the fire going all night whilst you sleep.

 

[Jared]

No idea how much the cost to have 1m sections delivered would be, but PF Bereg in Russia

Купить составную трубу дымохода | Официальный сайт ПФ Берег

Сегмент дымохода (труба) для походных печей Экономка, Вектор, Банная

bereg-ekat.ru

500 rubles is less than a fiver.

 

[birchwood]

I bought an 8 foot section of 2and a half inch pipe from our local metal suppliers for £10. Used a bit to make the angle coming out of the back of my stove. Before I could start making the rest of the chimney some rat bag nicked the rest of it out of my garden.

 

[kard133]

I lucked out and found a complete flue set for a frontier stove reduced to £20 on a boutique glamping tent website, with shipping it comes just outside of my budget, but still cheaper than the exhaust pipes.