Oil for Mixing Fuel

Shannon Muth · Jul 23, 2020

When I mixed my own fuel I used only Redline 40504 Alcohol 2 stoke oil. You can easily/safely mix at 12%

Glenn McClintic · Jul 24, 2020

Terry, when I mix fuel I have a 1000 ml graduated cylinder. I start with the oil. For 12% I add to the 120 ml line. Then I add nitro. For 65%, I fill to the 770 ml line. Then pour in methanol to the 1000 ml line. Then stuff a fine mesh screen in the top of a gallon can and pour it in. Repeat maybe 2 more times and I have most of a gallon.

If you mix by weight, would you zero out a beaker and then pour in 120 grams of oil, then add 650 grams of nitro and then add 230 grams of methanol? Does it work like that?

Thanks - Glenn

Terry Keeley · Jul 24, 2020

Glenn McClintic said:
Terry, when I mix fuel I have a 1000 ml graduated cylinder. I start with the oil. For 12% I add to the 120 ml line. Then I add nitro. For 65%, I fill to the 770 ml line. Then pour in methanol to the 1000 ml line. Then stuff a fine mesh screen in the top of a gallon can and pour it in. Repeat maybe 2 more times and I have most of a gallon.

If you mix by weight, would you zero out a beaker and then pour in 120 grams of oil, then add 650 grams of nitro and then add 230 grams of methanol? Does it work like that?

Thanks - Glenn

Ya, sorta. Except you have to convert the volume (ml) to weight (g).

The problem with looking at the level in a beaker/mixing cup etc. is it's inconsistent. If you fill your beaker to a line and weigh it to the gram, dump it and weigh it again you might be surprised what you see.

I mix 4 liters in a gallon can, weigh the nitro first, then the alcohol, oil and finally the P.O. If you know the specific gravity of the liquid you can calculate what a certain volume should weigh.

Nitro is 1.13 (at 70F), methanol is 0.79, oil (castor/synthetic) is close to 1.0 and P.O. is 0.83.

To make 4l of your fuel:

4000 ml x 0.65 = 2600 ml x 1.13 g/ml = 2938 g of nitro.

4000 ml x 0.23 = 920 ml x 0.79 g/ml = 727 g of methanol.

4000 ml x 0.12 = 480 ml x 1.9 g/ml = 480 g of oil.

I use 3 liter beaker for the nitro and alcohol and a 2 cup measuring cup for the oil. You could also just put your jug on the scale, zero it and add the ingredients but if you overshoot the weight you're hooped.

You did ask for the time, right?

Glenn McClintic · Jul 27, 2020

Terry Keeley said:
Ya, sorta. Except you have to convert the volume (ml) to weight (g).

The problem with looking at the level in a beaker/mixing cup etc. is it's inconsistent. If you fill your beaker to a line and weigh it to the gram, dump it and weigh it again you might be surprised what you see.

I mix 4 liters in a gallon can, weigh the nitro first, then the alcohol, oil and finally the P.O. If you know the specific gravity of the liquid you can calculate what a certain volume should weigh.

Nitro is 1.13 (at 70F), methanol is 0.79, oil (castor/synthetic) is close to 1.0 and P.O. is 0.83.

To make 4l of your fuel:

4000 ml x 0.65 = 2600 ml x 1.13 g/ml = 2938 g of nitro.

4000 ml x 0.23 = 920 ml x 0.79 g/ml = 727 g of methanol.

4000 ml x 0.12 = 480 ml x 1.9 g/ml = 480 g of oil.

I use 3 liter beaker for the nitro and alcohol and a 2 cup measuring cup for the oil. You could also just put your jug on the scale, zero it and add the ingredients but if you overshoot the weight you're hooped.

You did ask for the time, right?

Glenn McClintic · Jul 27, 2020

Thanks Terry - nice description. I understand.

The specific gravity of the components are listed at a reference temperature (or temperature range)... Do you compensate mathematically for the temperature or do you measure with a hydrometer? Or do you mix in a controlled environment?

Thanks again

Glenn