MIXING YOUR OWN FUELS
Mixing your own fuel can be quite successful and Model Technics caters for home brewers by offering a range of selected materials but there are a number of points which should be noted:
1. Always buy good quality constituents and be particularly wary of 'cheap' methanols which can have a high water content or contain dangerous impurities. It would be a false economy indeed to make a low cost fuel that produced erratic running, corrosion or premature engine wear. And remember, an engine cutting at the wrong moment could result in the write-off of a complete model with severe damage to the engine and R / C equipment.
2. Unless you have the use of a ventilated inflammables store always keep highly inflammable liquids such as pure methanol in the open. Preferably store against a wall to give shade from the sun and cover with a tarpaulin.
3. Unless you have the use of a mechanically ventilated fume cabinet always mix in the open. The fumes from most inflammable liquids are heavier than air and will flow and collect low down. Just one spark from a shoe scrape or a static discharge from a nylon garment could cause a dangerous explosion.
4. Many additives used in fuels are poisonous and the greatest care should be taken when handling a chemical of unknown toxicity. The toxicity of methanol is frequently under-estimated and this can be extremely dangerous. Methanol can be taken into the body by the inhaling of vapour or by absorption through the skin and since the effect is cumulative over long periods it is possible for the concentration to build up to cause sickness, blindness, insanity and even death. Therefore never mix methanol based fuels inside (other than in a mechanically ventilated fume cabinet) and always wash hands immediately should they become contaminated.
5. When mixing by hand, only half fill the container to allow room for movement and shake vigorously for about 20 minutes. Also, with hand mixed fuels, shake well for several minutes prior to each flying session.
6. With home mixes using castor oil there is a tendency for 'small white fluffy lumps' to precipitate out of solution. They are particularly prevalent in cold weather or if the fuel has stood for some time and will be much heavier if the wrong quality of Castor has been used. Since these 'fluffy lumps' frequently cause carburetor blocking, many commercial mixers have developed additives to minimize this phenomenon, but for the modeller it is usual to disperse them with vigorous shaking or by filtering a really heavy 'invasion'.
7. Model Technics mix by volume, we would recommend you do the same, it keeps things straight forward.