Mountain Marathon cooking research

Stewart B has told me he uses solid fuel for MMs, and I remember Mark Rigby saying the same, while I’ve always used my MSR Pocket Rocket + gas.

With the Saunders looming in a couple of weeks I thought I’d check this out.

Stewart’s claimed advantages:

  1. Instead of a pan, you can use those foil containers like you get a Chinese meal in.
  2. You can just put the fuel tablet on the ground and use some stones to balance a pot (or foil container) over it.
  3. So overall you save loads of weight, compared to canister, stove + proper pot.

So I’ve done a little research into the weight savings and the pros and cons. The solid fuel I’ve used is hexamine, with a Highlander aluminium stove box.

MSR Pocket Rocket Highlander stove

The main question is: how much fuel (weight) is required for the event?

Method: I brought 400ml of water to the boil using both methods, and weighed the fuel before and after.

Result:

Gas: 6g used

Solid: 11g used

My estimate of how much water I’d need to boil during the event is:

Item Quantity of boiling water
2 pasta meals each or equivalent, each requiring 400ml water. 1600ml
3 hot drinks each, each requiring 300ml water 1800ml
Spare: 2 x 400ml 800ml
Total 4200ml

Therefore the required net weights of each are:

Gas: 63g

Solid: 115.5g

Of course you cannot take gas without a canister, which weighs 100g, and the Pocket Rocket which weights 86g, so the required gross weights are (without cooking vessel):

Gas + canister + stove: 249g

Solid: 115.5g

Now we need to factor in the cooking vessel. My aluminium pot weighs 174g. I’ve not got any foil containers, but I reckon you’d need to take at least 4, and these might weigh about 100g in total. I have actually used foil containers on a Pocket Rocket before, but it was a risky business both for stability and for burning through the bottom because the flame is so intense.

So this gives total weights as:

Gas + canister + stove + pot: 423g

Solid + foil containers: 215g approx.

A saving of c.200g.

And this is without taking the Highlander solid fuel stove that I used for the above tests; if you don’t fancy using stones, that adds another 116g, bringing the weight saving down to below 100g.

What about other factors?

  • Solid fuel leaves soot on pots/containers, while gas leaves them clean – OK, minor point.
  • Solid fuel really stinks, and I wouldn’t want it in the porch of my tent – what if it’s pissing down?
  • The solid fuel weight saving depends on not taking a stove, and relying on balancing on stones – I’m not usually in the mood for collecting evenly-sized cooking stones after running 25 miles in the hills!
  • Control: the Pocket Rocket has fine control for bringing to the boil or simmering. The solid fuel block is either roaring, or out.
  • Stability: the Pocket Rocket is always a bit terrifying, as it hard to keep it stable on the tussocky slopes that MM campsites tend to be made of. With solid fuel it would be as good as you could make it, but lower to the ground so perhaps more stable and wind resistant.

On balance I’m not convinced. The weight saving is not nearly as much as I’d hoped; if it had been 3-500g I’d switch like a shot, but I don’t think 100-200g weight saving is significant.  If the weather is set fair, and if I can find some foil cartons in time, I might give the solid fuel a go. But if it looks like it will rain, I’d prefer the clean reliability of the gas.