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Post  fredvon4 on Fri Mar 25, 2016 3:51 pm

I have spent the last three hours searching for a calculator know I have seen before

All I find are the ones for converting a already mixed fuel to have more oil or nitro

I need a calculator to blend fuel form zero

The math problem... I suk at arithmetic and I know the problem is very elementary

I want to break in my Fox .35 with this fuel....and I have all the components

15% nitro
28% total oil....Sig Castor and Ucon LB625
3% of the Oil synthetic

Obviously remainder methanol

I have ML graduated beakers
I have a container (Nagalene) that holds 500 ML

All the calculators I find have a starting blend and the amounts to change them

I am brewing fresh batch

Help please
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Post  KariFS on Fri Mar 25, 2016 4:07 pm

If you want to get a full 500 ml container of the specified mix, you need the following amounts of each ingredient:

75 ml of nitro
125 ml of castor
15 ml of synthetic
285 ml of methanol

Hope I understood your problem correctly Smile
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Post  OVERLORD on Fri Mar 25, 2016 4:09 pm

Hi Fred,

To make 1000 ml of fuel, you need:

150 ml nitro
280 ml of total oïl
30 ml of the synthetic oïl
The rest methnol

For 500 ml of fuel, you need half of each quantity

Hope this helps.

Lieven
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Post  fredvon4 on Fri Mar 25, 2016 4:20 pm

You guy ROCK

Blending now

Thanks very much!!!! I Love This Forum! This Site Rocks!
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Post  Ken Cook on Sat Mar 26, 2016 2:25 pm

Fred, you have two of the best fuel manufacturers  in the US practically in your backyard. Why the need to mix your own fuel? Is this a experiment? In addition, why the 15% nitro? Ken
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Post  fredvon4 on Sat Mar 26, 2016 2:56 pm

Ken

All the brews I have ( Rich's brew) are set for specific engines and most of my stock is too high nitro

I had bought some Torco Nitro and meth and had on hand Sig Castor, Klotz, and Ucon LB625

I don't trust the analysis of some of my (bought for RC) LHS fuels due to volume vs weight factoring of OIL

So instead of trying to re-blend the gallons I have...doing a small batch of a blend just for the stunt 35 was easy ecept all my beakers were ML and the recipes seem to all be in OZ and was hurting my head

10% nitro would have been fine, but the guy who is flying and trimming here uses the mix I described for his Fox 35 ringmaster so I decided to just blend some that way for the break in and initial flights

So far it runs fine, east to start, and the ST needle stays where I set it....about 7 heat cycles done yesterday and today and about 1/3rd the 16oz still to run

I do not have an anti burp plug installed and hoping I won't need one
Every thing by ear right now and tomorrow I will start fiddling with the tach and compare to what others report for this engine and a APC 10x4

All that said, I will probably blend some 10% N and see if it work fine ( I assume it will)

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Post  Oldenginerod on Sat Mar 26, 2016 5:31 pm

fredvon4 wrote:.... all my beakers were ML and the recipes seem to all be in OZ and was hurting my head
Fred.
Peronally, I don't know how you guys work in Ounces.  If you understand percent, then working in MLs is a piece of cake.  I blend all my own fuel at various different mixes and find it easy.   I even got some buggy fuel cheap and use it to custom blend what I want by adding more oil or nitro.  I love the metric system.
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Post  Marleysky on Sat Mar 26, 2016 7:45 pm

Oldenginerod wrote:
fredvon4 wrote:.... all my beakers were ML and the recipes seem to all be in OZ and was hurting my head
Fred.
Peronally, I don't know how you guys work in Ounces.  If you understand percent, then working in MLs is a piece of cake.  I blend all my own fuel at various different mixes and find it easy.   I even got some buggy fuel cheap and use it to custom blend what I want by adding more oil or nitro.  I love the metric system.

HA! HA! Haa.  I don't recall the exact date or under which president the Good Ole USA was to move over to the metric system. I know I got all sorts of Upset/PO'd when i started working on cars that had a mixture of SAE and Metric Bolts and nuts....IT was a communist plot to destroy America. I had a T-shirt that said in big bold letters:                                                                             " Fighting the Metric System...Every INCH of the way!!"
My kids were taught in metric, phhftt It's nothing to them to them MM CM...like a duck on water.
I still curse when I have to get  two sets of tools out to work on my car(s) Just bought 2 new sets of allen (Hex) wrenches one in MM and one in SAE....Of course I did just get the JIS set of screwdrivers for Christmas guess I'm  gonna need a whole new drawer in the tool chest!! I'm still being converted.
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Post  RknRusty on Sun Mar 27, 2016 12:45 am

Damn, I just spent a half hour writing... and losing, an entertaining explanation of the unwieldy fractional mess used in the inch system compared with the sensible metric system. Here it is again in a nutshell. We have to measure with overlapping 128ths, 64ths, 32nds, 16ths and 8ths, etc, ad nauseum, and also represent them with the decimal equivalents that accompany them... ridiculously head scratching when quick recall is necessary, but right at our fingertips with metric measurements requiring almost no brain energy. Everything metric adds evenly up to a hundred or a thousand.

Ten millimeters is a centimeter. A thousand millimeters or a hundred centimeters is a meter. And for solids, a thousand grams is a kilogram. A thousand kilograms is a metric ton. Again, with fluids, only the names change. A thousand milliliters is a liter. Btw, a milliliter and cc of water weighs one gram, so a cc is the same as a ml on many syringes. In other words, 1ml=1cc=1g of water. Any one of those is also a thousandth of a liter of water, so 1000cc of water is also a liter, same as 1000ml and 1000g. But since oil and other fluids have different density, always use volumetric measuring tools like measuring cups, graduated cylinders and syringes. Many syringes interchange cc and ml.

Percentages fit right in because one percent is one hundredth of anything(.01 x anything). Eg. .01=1%, .1=10%. 1.0=100% So for a liter of fuel, or a thousand ml of fuel, 10% nitro of 1000 would be 100 ml or 100cc(.1 x 1000). 29% castor would be 290 ml or cc(.29 x 1000=290). Since it has to add up to 1000, then the balance of alcohol is 1000ml - 100ml(nitro) - 290ml(oil) = 610 ml or cc. 100nitro+290oil+610alky=1000ml(1 Liter) fuel.

Okay, I hope that helps someone more easily conceptualize how to think metric.
Rusty

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Post  ian1954 on Sun Mar 27, 2016 7:29 am

There are pros and cons of any system. I was taught both systems but will be happier when the metric fanatics stop knocking the Imperial system and vice versa.

The metric system when introduced in the UK was cgs (centimetre, gramme, second) and we talked and, still do, about cc when referring to engine sizes ( I do not have a 1200 ml motor bike!) - this has slowly changed to mks (metre, kilogram, second).

I find that there are many instances where the Imperial system is better.

When wood working - being able to divide by two and change to a different scale on the ruler is an advantage.

For example, I have two pieces of wood - similar size - one metric and one imperial. I need to slice this into equally sized pieces.

So a piece of balsa 1ft (12 inches) long and a 25 cm (250 mm) piece.

I want two equally sized pieces.

I take the 12 inch piece, divide by 2 and - easy, peasy - two 6 inch pieces.

I take the 250 mm piece, divide by 2 - and easy, peasy 125 mm


I want four equally sized pieces.

I take the 12 inch piece, divide by 4 and - easy, peasy - four 3 inch pieces.

I take the 250 mm piece, divide by 4 - and mmmmmmmm....... 67.5 mm

I want eight equally sized pieces

I take the 12 inch piece, divide by 8 and - easy, peasy - eight 1 1/2 inch pieces.

I take the 250 mm piece, divide by 8 - and mmmmmmmm, grrrrr! (calulator time!)....... 33.75 mm

Try finding a ruler with .25 mm!


It goes on 3/4 inch - 16.875 mm.

Remember that these are not metric equivalents of imperial. Just the simple dividing by multiples of two that we do to maximise the use of timber.

Luckily, in the UK - board materials are still sold as 2440mm x 1220mm - 8ft x 4 ft.

When measuring liquids or obtaining percentages the metric system is easier to work with.

My fuel mixes are prepared from ingredients supplies to in 5 litre, 1 litre, pint and gallon containers.

I use straight sided containers for mixing and the measurement system doesn't matter when mixing by volume. Just measure up the side and mark it according to the percentage.

If you just want a pint of fuel, take your pint can and fill the container - mark the container and pour it back into the can. You now have a container that is measured for one pint - you can do this with a litre as well - doesn't matter.

Measure down the side - imperial or metric - it doesn't matter.

Then apply the percentages to the length of the mark to the bottom of the container.

So you want 15 % nitro - the mark you have measured is 165cm or 6 1/2 inches.

Every % will be 1.65 cm so 15% will be 24.75 cm (247.5 mm) from the bottom of the container.

If you want to do this in imperial - look at your ruler and the smallest divisor. Say it is 1/16" then convert the 6 1/2 inches to 1/32.

6 1/2 inches is 208/32 - so 15% is 15 x 208/100 = 31.2/32 - 1 inch near as damn it!

Everything depends on the measuring devices you have, nothing is insurmountable.

I have various marked containers - I only usually mix a pint at a time - one marked they are reused.

The thought is that although the metric system makes it easier, you have to mix to amounts divisible by 100 - you can, with any measuring system - use any straight sided container to do a % mix by volume.

I use both metric and imperial , flipping between the two when convenient. Prefer pints of beer and mph!






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Post  JPvelo on Sun Mar 27, 2016 8:09 am

Babe Bee
ian1954 wrote:

I use both metric and imperial , flipping between the two when convenient. Prefer pints of beer and mph!


Preferably not at the same time!
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Post  fredvon4 on Sun Mar 27, 2016 9:42 am

1000/2 =500
15% N = 150/2=75
25% C = 250/2=125
3% S = 30/2=15
=430
remainder M
------------------
1000 - 430 = 570/2=285 M



Talk about perishable skills......grrrr

I used to be very very good with Microsoft Excel and created some extremely complicated spread sheets with dozens of variables and auto calculation cells

Spent some time trying to build a sheet that will let you put in total desired, percent of three of the 4 ingredients to convert to ML of each and solve for the remainder Methanol

And from that I was trying to set it to take a know quantity of a already mixed and poke in known percents with the goal of computing desired changes to the mix IE start with 10% N and how much needed to make 15% N etc...

seems being away for 5 years and not working with this every day has me spending way to much time reading the tutorials again
Sure wish my computer instructor was still alive...he could write the spread sheet and nice user input format in less than 15 min including conversion to any system of liquid measurement be it drams, OZ, weight ( must know specific gravity of each at roon Temp) or ML
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