Well said.

Out of interest i went looking for MSDS for Klotz Techniplate and Benol for the density information. All the ones i found Benol don't list density. If you are only making a quart/litre at a time to keep it as fresh as possible surely volume is easier option. If i was a fuel manufacturer and making huge volumes in vats etc then weight is probably an easier option especially if nitro/oil components are a little less in my favor being the most expensive part of the fuel.

Pump systems are very good in measuring flow volume. Small manufactures can mix their fuels at chemical companies who mostly do supply such services, the larger fuel companies probably have their own systems.

Its just that smal volumes gets more critical to get right, so if a fuel mfg uses a barrel at the time it will deviate less if anything at all.

The information has been available for all Klotz products, and if nothing else the MSDS is in most (all?) countries mandatory to supply.

Klotz doesn’t have a traditional SDS on their site. They have a technical write-up, but it’s not very technical. I do know from my own measurements, Klotz Techniplate is .995-1.00 g/mL @ 68 degrees F. Castor oil (virgin first pressing) weighs .94g/mL. Nitromethane has varied slightly - 1.14-1.17g/mL and methanol is pretty rock solid at .791g/mL. I have never found the need to use Benol as virgin castor works quite well and is significantly cheaper, but I’d suspect the density of that to be similar to virgin castor at around .94-.97g/mL

I do not recommend basing one’s weights solely off an SDS as they can be measured at different temperatures. The density of the components changes with temperature - especially the nitromethane. It’s good practice for fuel home brewers to measure the density of each component each time you mix fuel if the climate in your mixing area is different. Keeping the chemicals in the same climate and at a consistent temperature will avoid the need to measure the densities each time. This has proven superbly reliable for me and I think the performance of my trucks in my videos shows that.

No, the whole point in using density of the MSDS is that you can never get it accurate enough at home, unless you use seriously large containers or lab equipment. Going by weight will always result in the same amount, volume changes with temperature, not the mass that you need. So even if they do measure at different temperature your fuel recipe will be accurate with that oil, changing oil will require a new recipe anyhow.
BeNol is 0.962 (very close to pure), Techniplate 1.002.

Fair enough. I guess what I was trying to say is measuring by weight is more accurate, but you must have a baseline weight to weigh to. If you don’t know what your target weight of mixed fuel is to be, there is no way to measure by weight blindly. Using a given volume - say 10% of 1 gallon of Klotz techniplate; or 12.8 fluid ounces (378.5mL) will weigh 379.2g (@1.002g/mL). Now if you weigh a given mixed fuel volume at (hypothetically) 3400g, Your 10% oil by volume is actually 11.1% by weight. So if the recipe changes at all, your final weight is going to differ. You’re pretty much relegated to using volume in some fashion no matter what, but knowing the densities of the components makes it really easy to weigh it out and be really accurate. I have yet to meet an engine that ran adversely different if one of the components is off by a fraction of a percent. A dyno will likely be able to show the difference, if it’s sensitive enough.

Benol weighs more likely because it has a few additives in it making it denser than virgin castor.

Yes, volume is needed in some way or another. If a drop of fuel should contain.. say 1000 molecules of oil, then that is what matters.
The weight of those 1000 molecules will always be the same, even if they displace different volume due to temperature.
Some oils is really sensitive, though I doubt there is any difference in power, you can't blend small batches and make it accurate enough for testing purposes. Well you can see if it works or not, but not if it's optimal.

I agree it would be difficult to get physics level accuracy in the home without some precision instruments... In the grand scheme of things, through process of elimination and some experimentation, one can find the most optimal blend for a given scenario by collecting some simple data.

Do you have a lab to test the accuracy of your fuel blending to find the optimal blend, or do you just find what works best and use it? I mean, we are dealing with micro sized 2-4hp engines, not 2000hp top fuel dragsters. At what point do we get too pedantic with a subject such as this? Not trying to fling poo or start a keyboard war. Far from it actually - I would hope by now you know I’m not like that and have a lot of respect for your level of knowledge.

It's a very valid question, and very hard to answer... You need to draw the line somewhere, and say enough is enough, though the later you say that the better.
In onroad it would be somewhat easier to find what works as you can measure average lap times easier and all out power is needed, as dust is less of a problem you could find how the engine wear more easy as well.
For offroad things gets more complicated for sure...
But it's a matter of finding boundaries for every component (so if you aren't willing to blow up engines forget it), categorize and use as many labels as possible, taking notes after notes, measuring what can be measured all the time. Then trying to mix them now knowing how everything works by itself, so you can see if a pattern emerge.
It's easy enough on these small engines, try it on full size engines, it's a nightmare.

After running some commercial fuels I can say that they are all about pushing products fast and easy, some have never done any real hard testing.
And if people would know how sensitive it can become sometimes, people (even top pro's) would blame the fuel far more often then they blame their engines today. They have made an incompatible choice between engine setup, car setup, fuel etc, and just failed to adapt to the situation but in the end blames the engine.

Well said and duly understood. I do my testing on asphalt with a stopwatch on a measured section and figure the results from that. I’ll be doing a lot of pavement tests now that I have a few different platforms and a few different engines. It’ll be interesting to see how things stack up.

Just make a list of what you expect, for bashing you don't need to over complicate things.

I don’t think it needs to be overly complicated for racing either. Sure, some testing must be done... However, I have my doubts that onroad will have a significantly different need in a fuel blend than off-road will. Like you’ve said time and time again - “it’s all in the oil package”. Getting that right makes everything in the world right.

You can have fuel that works for both, but some is completely tailored (even if they don't know it) and might give some problem. Just different demands that needs different solutions.
I doubt it will make the whole world a better place, more likely an oil debate on some forum that will give us WW3...

That’s usually how it goes. Oil debates never end......well....