Black Widow RPM

The Black Widow has the same crankshaft as a Babe Bee. The Black Widow is basically a Babe Bee. The standard cranks dont last long at 20K rpm and above.

Tell us more about "sical" cant find anything about it on Google???

Here in Oz you can get a fuel called "Black Magic" which is 30% nitro and has a very dark colour hence the name. I have heard that Cox Fuels had a distinct and unique smell.

For those who may want to use Missile Mist, check it out on the Fox site. It has 24% nitro, but it also has only 17% castor oil for lube. Were I to use it (and I have), I would add a few percent more lube to bring it up to 20%-22%.

Just one opinion.

George

http://www.foxmanufacturing.com/index.php?main_page=product_info&cPath=174&products_id=1494

Wow,,still available. How may oz(?) of castor would a person add to get that gallon to 20% oil?.

PV Pilot wrote: How may oz(?) of castor would a person add to get that gallon to 20% oil?.

Add 4.8 oz.

Final blend: 23.1% nitro, 20% castor

Here's a castor oil calculator I wrote that's posted on Bernie's site: COXEngines.ca

coxengines.ca/castor.xls --- It does require that you have Microsoft Excel on your computer.

andrew

Thank you Andrew!

So is it safe to say that 4.8 Oz will raise the castor percentage up 3%??,,as a general rule for a gallon of fuel??.

I often wonder if the aforementioned "crank failures" were due to improperly balanced props and engines. Vibration will destroy these little engines QUICK!!! I've never had a crank break because of high rpm because I balance everything. I once had a driveplate spline fall off due to bad steel/workmanship.. The entire crankcase was promptly replaced, free of charge, from Cox...

PV Pilot wrote:
So is it safe to say that 4.8 Oz will raise the castor percentage up 3%??,,as a general rule for a gallon of fuel??.

No, that holds only if the existing oil content is 100% castor. Many of the fuels today are synthetic/castor blends, so that ratio must be taken into account when calculating the amount of additional castor. Quite commonly, we see an 80/20 syn/cas oil mix. In that situation, it requires more castor oil to push to total castor content to the desired level.

The castor oil calculator uses the synthetic/castor ratio when doing the calculations.

andrew

warrenlead wrote:The Black Widow has the same crankshaft as a Babe Bee. The Black Widow is basically a Babe Bee. The standard cranks dont last long at 20K rpm and above.

Tell us more about "sical" cant find anything about it on Google???

Here in Oz you can get a fuel called "Black Magic" which is 30% nitro and has a very dark colour hence the name. I have heard that Cox Fuels had a distinct and unique smell.

Sorry it is not a nitro substitute but an additive here is the lowdown on the fuel:

SYNERGETIC means ‘working together’ for a total benefit which is greater than the sum of the parts. Many of the additives in SICAL produce more than one benefit and some also ENHANCE THE BENEFITS of other additives.

The main group of IGNITION ADDITIVES are known as ACB because they act as an Autoregulating Catalytic Booster. With glow engines there are many power strokes where ignition is late, or very late, or fails to take place at all. This can be demonstrated with a rev counter where the RPM can be seen to be varying by about 100 rpm every few seconds, due to these poor power strokes. It is even more obvious at tickover where the engine runs quite roughly because of missing. This erratic ignition timing is brought about by the mechanism by which the glowplug works. With the plug cavity initially full of exhaust fumes from the previous cycle, and the new mixture swirling into the cavity, it is not difficult to see that there will be some power strokes where the mixture in the cavity will be too impure to ignite at the required time. On these occasions ignition will be late, very late, or not arrive at all.

So, how do we induce ignition when the mixture is a little too impure to ignite? The answer is to put a CATALYST into the fuel. But, if we put a ‘normal’ catalyst in the fuel, it wouldn’t just correct the ‘poor’ power strokes, it would also advance the ignition on the ‘good’ strokes and cause pre-ignition and overheating. Therefore the solution had to be a lot more sophisticated. ACB is not a simple chemical but a complex of chemicals and it is designed to change form and only become catalytically active at a certain critical temperature. In practice this means that ACB will not promote a pre-ignition since it only becomes catalytically active at a point when ignition is required. But, an otherwise late ignition, or non-ignition, will be encouraged by the catalytic effect to ignite close to, or actually on, the required ignition point.

So, what benefits does ACB give? Firstly, SUPERSMOOTH RUNNING: checking the RPM will typically show a reduction in ‘hunting’ from 100 rpm down to around 30 rpm. Because the ‘poor’ power strokes become ‘good’ power strokes it is usual to see several hundred RPM increase in maximum speed. Also, because ‘late’ power strokes are greatly reduced, the wasted heat of combustion is also reduced and this usually results in a decrease in the running temperature of the cylinder head of around 10°C at high revs. This feature can be of substantial benefit in cowled installations where engines go ‘hard’ and lose power from overheating. At tickover, the benefits of ACB are even more obvious. The tickover becomes smoother and more reliable while the pick-up from tickover is cleaner and stronger. Furthermore, this stronger pick-up will be experienced throughout the rev range; so with installations where strong engine acceleration is required, such as car racing, ACB will be particularly appreciated.

The main COMBUSTION ADDITIVES in SICAL combine with ACB to effectively widen the explosive limits of the fuel to produce what we call the BROADBAND EFFECT. This means that the number of ‘clicks’ that give ideal mixture - not too rich not too lean - could be as much as doubled or more. This makes needle valve settings very uncritical and ensures reliable performance throughout the run, even in the most demanding situations. This same combination of additives encourages a slightly faster burn with less likelihood of detonation, which is particularly usefuel with high nitro fuels. The other COMBUSTION ADDITIVES in SICAL are to keep engines really clean inside. This enables engines to run at peak performance, month in and month out, without a power sapping build-up of varnish and carbon.

Most LUBRICATION ADDITIVES are compatible with synthetic and vegetable oils in the necessary proportions, but there are some extremely desirable ones that can be problematical. However, in the presence of methanol and some other additives, they can happily be used. Since we put the SICAL additives into the fuel mix, rather than the oil, this allows us to use these rather special lubrication additives. Of course the EDL2 oil in the fuel already contains it’s own excellent lubrication additives; so we had to ensure that the actions of the EDL2 additives would only be enhanced by the SPECIAL LUBRICATION ADDITIVES. This took many hundreds of hours of testing but the outcome was total success. So, what do the Special Lubrication Additives do? The first group of SLA’s work with the EDL2 additives to give the ultimate protection against CORROSION; vitally important when you realise that more engine failures are caused by corrosion than any other reason. They protect against corrosion of steel, aluminium, bronze, brass and similar alloys. The second group of SLA’s work with the EDL2 additives to REDUCE ENGINE WEAR to an absolute minimum and give the engine GREATLY EXTENDED LIFE. The anti-wear protection is for all types of metals and bearing surfaces contained in model engines.

We do not claim that if you PUT A SICAL IN YOUR TANK it will make a spectacular difference to the way your engine performs but it will improve the running in so many ways and they add up to what we at Model Technics call SUPERSMOOTH POWER - which gives excitement, enjoyment and satisfaction as well as reassuring reliability.

So it's smooth running AND it smells good.....

nitroairplane wrote:

jetpack wrote:

PV Pilot wrote:I took the can back to show him and remember him topping it off for me with some 1/2A? glow fuel called "Missle mist".

I remember it also smelled sweet. Maybe the first to use synthetic or just had their own scent they added? Was it K&B that made it?

would they do that?

Missile Mist is a fuel still available from Fox. It has 24% nitro but only 17% castor lube, so you may want to add some castor.

K&B's synthetic lube was called X2C. Their fuels, such as K&B 100 were castor lubed, if you used synthetic it would be K&B 100+ (the plus indicating synthetic). That may have changed over the years.

I believe the sweet smell was from earlier years when nitro benzine was added to fuels until they found that it was harmful to people.

At least that's the way I remember it.

George

Nitro Benzene was exra item added to fuel for smell. I have some pulse jet fuel that is 80% alky with 20% propolene oxide. I want to mix a small amount of this to some fuel and also Hoppes gun solvent. The solvent has very strong small of nitro bebzene. I have a real old bottle and this is listed on ingreients. The new solvent doesn't say but smells the same. Only problem is I don't want to ruin and of my engines as they are all good. I have a pint of Areo-dyne Dynamite 65% nitro fuel for FF. Someday gotta try both.
Dan

dankar04 wrote:Nitro Benzene was exra item added to fuel for smell. I have some pulse jet fuel that is 80% alky with 20% propolene oxide. I want to mix a small amount of this to some fuel and also Hoppes gun solvent. The solvent has very strong small of nitro bebzene. I have a real old bottle and this is listed on ingreients. The new solvent doesn't say but smells the same. Only problem is I don't want to ruin and of my engines as they are all good. I have a pint of Areo-dyne Dynamite 65% nitro fuel for FF. Someday gotta try both.
Dan

We have a company in the UK that will
Mix fuel for you I think they will put almost anything you like in it.

nitroairplane wrote:

HHHHmmmmmm who is the Ignoramus in that situation Dave?[/quote]

nitro:

If humor has to be explained it ceases to be funny. Not wishing to do that I'll leave you to ponder.

Enjoy!

SuperDave wrote:

nitroairplane wrote:

HHHHmmmmmm who is the Ignoramus in that situation Dave?

nitro:

If humor has to be explained it ceases to be funny. Not wishing to do that I'll leave you to ponder.

Enjoy! [/quote]

well who is it?

dankar04 wrote:Nitro Benzene was exra item added to fuel for smell. Dan

Easy with that stuff,,highly toxic human carcinogen.

PV Pilot wrote:

dankar04 wrote:Nitro Benzene was exra item added to fuel for smell. Dan

Easy with that stuff,,highly toxic human carcinogen.

Yes as i said before thats why they stopped using the stuff.

nitroairplane wrote:

SuperDave wrote:

nitroairplane wrote:

HHHHmmmmmm who is the Ignoramus in that situation Dave?

nitro:

If humor has to be explained it ceases to be funny. Not wishing to do that I'll leave you to ponder.

Enjoy!

well who is it?[/quote]

Nitro:

Well, awlright (sic), the "Ignoramus" is anyone that believes that "RPM's are everything" per my quote from "Ignoramus" which, BTW, was dated 2011 and not related to any distant British play by the same name.

Actually RPM's are only one measure of engine performance. Surely you know the rest.

(blank stare from nitro the "deadpan") "Huh?" he sez. Courtesy laugh optional but expected.

SuperDave wrote:

nitroairplane wrote:

SuperDave wrote:

nitroairplane wrote:

HHHHmmmmmm who is the Ignoramus in that situation Dave?

nitro:

If humor has to be explained it ceases to be funny. Not wishing to do that I'll leave you to ponder.

Enjoy!

well who is it?

I fully understand the text and the subtext there.
And know that I provoked the
Comment but what I stayed was intact correct.

Nitro:

Well, awlright (sic), the "Ignoramus" is anyone that believes that "RPM's are everything" per my quote from "Ignoramus" which, BTW, was dated 2011 and not related to any distant British play by the same name.

Actually RPM's are only one measure of engine performance. Surely you know the rest.

(blank stare from nitro the "deadpan") "Huh?" he sez. Courtesy laugh optional but expected.[/quote]

With my not being a contest person, I'm probably outside the realm of this thread, but my very long-run Blackwidow still reliably pulls about 13000 RPM on a 6-3 prop and 24% fuel...even with it's glowplug adapter.

This is plenty of power fro it to drag my Bird of Time Sailplane to a decent altitude, even when packing a camera. I often fly it out of areas where a faltering engine could cause me some time in the shop, so my priority is dependability.

Kim, That seems like an aweful lot of weight and drag for an 049 reed of any kind and to have it pull good like your enjoying is stating a lot about the power of them especially for their own size and weight. Seems to be designed perfect for the task. I bet it seems happy to do it.

dankar04 wrote:Nitro Benzene was exra item added to fuel for smell. I have some pulse jet fuel that is 80% alky with 20% propolene oxide. I want to mix a small amount of this to some fuel and also Hoppes gun solvent. The solvent has very strong small of nitro bebzene. I have a real old bottle and this is listed on ingreients. The new solvent doesn't say but smells the same. Only problem is I don't want to ruin and of my engines as they are all good. I have a pint of Areo-dyne Dynamite 65% nitro fuel for FF. Someday gotta try both.
Dan

Hoppe's No.9 does a wonderful job of cleaning carbon and castor. Does not hurt a thing. Nothing hides from Hoppes fluid. Everything comes out new from it. I use wire twist ties to attach to parts and hang the wire over the top of the jar and let it soak.

Hoppes has another called Bench Cleaner that desolves copper at a slow rate. Use it as a short dip method of cleanining brass. You can clean a piston very well in this but always be sure to flush it out the socket with brake cleaner or it will ruin a piston.