Conference vmszoo::rc

    what was the problem you had? (is this "blast" fuel the fuel
    sold at Tom's )I use power blast fuel and would like to
    avoid and unpleasant experience if I can
                                                    thanks
    

    
    		I believe Power Blast is the same stuff and is
    	made by Tom. 
    		I ran 12% blast throught my engine the weekend
    	before last and when I went to the field this past weekend
    	I found that my main bearings had rusted almost solid.
    	I must in all fairness say that I did not after oil my
    	engine. I was able to get it running again but it just
    	doesn't feel right and I am now trying to find out how to
    	repace the main bearing because of the rust pit left on
    	them. Also the most experienced flyers at the field I go
    	to tell me that the stuff is trash. That and my own 
    	experience is good enough for me.
    	
    				Mike
    

    Interesting...  I have had problems with power blast also.  A couple
    years ago I lost the compression on my ENYA .46 4-stroke and found
    that the valves had to be re-ground.  It didn't have many flights
    on it when it happened.  The same thing happened to a friend with
    an OS .40 4-stroke and he had to replace the cylinder head.  We
    were both new to 4-strokes but took care not to lean them out too
    much, and followed the advice of experienced 4-strokers.  Only
    difference was that the experienced guys were using Red Max and
    we were using power blast.
    	Anyhow, word got out that the power blast had too much rust
    inhibitor (probably marvel mystery oil) and was gumming up the valves.
    I guess the valves stick and holes get burned in the valve seats.  I
    heard that a lot of 4-cycle engines were destroyed by it, but that is
    strictly through the rumor mill.
    	Since then I have used only Red Max on my 2- and 4-stroke engines
    and have not had any problems.
    	I don't recall hearing of any rusting problems with 2-stroke engines
    running power blast.  Maybe they took out too much of the rust
    inhibitor!!!  Anyone else out there had trouble with power blast??
    
    P.S. You probably know this, but it is a good idea to run all traces
         of raw fuel out of your engine and lubricate it with marvel
         mystery oil at the end of each flying day.  Raw fuel attracts
         moisture fast!
     							Bill
    
                       

    Please excuse me but this is a bias opinion.
    
    Power Blast is for S**t........................
    
    Red Max is better, but it still hasn't got the punch.
    
    Go to a Pattern Match and see what is the #1 RUN FUEL... it will
    be S&W.
    
    That's why I'm bias. I use and sell S&W and have had no problems
    on 2 or 4 strokes for three years. No customer of mine has had any
    issue either.
    
    							Tom
    

    Since we are discussing fuel, how do you tell what percent of nitro
    is best for your engine?  In the last year, I went through almost
    two gallons of ""BLAST"" and I'm almost out!  No problems with rust,
    but why take chances.  I have an  OS.15 and a OS.25.  What fuel
    should I buy?
    
    Ken
    

    
    Percentage of Nitro has to do with engine port timing. Most std
    sport engines are mid ranged timed. If not they tend to be timed
    toward the high side. This equates to 11000 to 13,500 RPM. For
    these engines the standard is 8 - 15% nitro. This depends on how
    your engine runs. A good starting point is 10%. As an example I
    run a Low timed engine in my Pattern bird and use 5% nitro. This
    gives me maximum torque at about 12500 RPMs on a 11/10, 12/9 prop.
    A formula one racing plane runs high times at 23000 RPM on 60%
    nitro. I think they are turning 8/7.5 props. Average speed is
    somewhere around 160 mph.
    
    						Tom

    RE: .6  -  Can't tell you what the "ideal" nitro percentage is,
    but I put about four gallons of Red Max 12% through my OS .25FP
    last year.  No problems, good smooth idle, and it runs like
    new this year.  Do you know what percentage your blast is? I
    seem to recall the most popular mixture was 15% with that stuff.
    For just fun flying, the lower nitro is fine and your engine runs
    cooler.  I would try 10% but I tend to stick with what I know
    works.
    							Bill
     

Why use Nitro at all. I know it is inbuilt into the American modeller to use 
Nitro, but seriously with very few exceptions it is not worth the expense.

In my Sport model I run a mix of 10% Glo Glyde oil 5% Nitro and 85% Methanol. 
Stu Richmond (Model Builder) will concur that more than adequate power and 
reliability is achieved at this ratio as I gave him a demo this last weekend.

In F3D Pylon we use straight 4:1 Methanol to Castor, admittedly we use Tuned 
Pipes but your team of Shadel, Richmond and Jett were not much slower than the 
F1's using heaps of Nitro.

The addition of 5% Nitro improves the idle and makes the engine easier to 
start, any more is increasing the available power but does not improve 
reliability and in fact once you go above 25% it makes the engine less reliable 
and increases wear.

Light those flames.

John

All stuff we mix with methanol have their own advantages and also disadvantages:

Pro Nitro:
==========

- While burning, it produces oxigen. So, you can adjust your carb more fat and
  the burning process will be less hot (Re .8 your engine will run cooler with
  Nitro!).
- Improves idle
- Easyer Carb adjustment
- Good lubrication

Con Nitro:
==========

- Expensive
- Aggressive oxydants (==> rust)

Whats best about Nitro:
=======================

Use as small percentage as possible (keep price low, avoid rust). To achieve
smooth idle (specially 4-strokes) is Nitro very very helpful.


Some important facts about rust inhibitors: Most (maybe all) rustinhibitors 
works well at 'normal' temperatures. If they are hot, like in an engine, they
turn to the contrary and will be very aggressive. On the other side, performance
of the engine will of course not improve, because there is less methanol and
less nitro. If you use fuel with rust inhibitor, then you will burn a lot of 
this expensive stuff and you don't have any benefit. 

What is best, to avoid rust: Use rustinhibitor after run. I am using as rust-
inhibitor some weapon-oil wich is cheap, very strong neutralizing and is a well
lubrificant.

    
    This is my 2 Rappen word (Rappen = Swiss cent).
    
    Franz

    I have run both 10% and 15% nitro (Red Max) in the helicopter, and
    found that using the 10% nitro, I had to run the engine quite a
    bit leaner.  My personal feeling is that in this application, the
    leaner running engine would tend to spell disaster, since cooling
    in a chopper is a problem.  ( I would expect the same to be true
    in both gas cars and gas boats.)  I don't know of anyone that I
    fly with that use less than 10% nitro in their choppers and many
    of us use 15%.
    
    Ken

    I've consulted books about the topic: In note .10 I was wrong: There
    is no lubrification effect into nitro. 
    
    Another important point: If the air humidity is very high (75 %
    or more) then nitro can cause some problems (pre ignition).
    
    If you mix your fuel yourself, dont buy yellow nitro. A yellow colour
    shows that it is old very agressive.
    
    Within our club, we are using our standard fuel for four-strokes:
    
    		75 % methanol (more than 99 % pure)
    		10 % castor
    		15 % nitro
    
    My after run treatment (every evening after flying): 
    
    	- Restart the engine, to burn out the rest of fuel
    
    	- Put some oil (good car oil does the job too) into carb, 
    	  exhaust and crankcase and turn the prop a few times.
    
    This after run treatment is specially for four stroke engines very
    essential: the crankase contains more aggressive stuffs than into
    two strokes.
    
    Looking forward for a good flying weekend.
    Franz

    Don't know about the 10% but I've bought Red Max 15% helicopter
    fuel. It's the darker color to make it easier to see in the fuel
    tank while the copter's flying. No sense doing unexpected
    auto-rotations. I,ve been told that the only difference between
    the pink 15% Red Max and the Heli fuel is the coloring added and
    some extra anti-foaming stuff.
    
    Dan Eaton

    Red Max fuels come with a bunch of different color additives.  I
    know if you buy the economy versus the premium fuel, one is kind
    of a junky green and the other (premium) is pink.  I am not sure
    if there is a list of color codes that they use or what, but it
    does not have to do with the percent nitro.
    Ken

Re: .17

<    If you mix your fuel yourself, dont buy yellow nitro. A yellow colour
<    shows that it is old very agressive.
    
This note is in error for the majority of Nitro. Angus Chemical Company of
Northbrook Illinois manufacture most of the Nitro we use today giving it the
brand name of "Nitrofuel". Nitrofuel is 95% pure as 100% nitro cannot be
shipped within or out of the US, Angus also add a dye called "Nitrogard" which
is normally yellow in color if the nitro is clean and safe. Nitrogard turn's
blue if the Nitro is contaminated and dangerous, if the Nitro is blue it 
must be disposed of carefully and in accordance with Government regulations.
Angus have an Emergency phone (1-318-665-4451) for obtaining first aid and
emergency help. 

Nitro is sold by Angus to the major US fuel manufacturers without Nitrogard and 
the resulting nitro is clear, however this nitro is not permitted to be sold to 
the general public. If you ever see clear nitro it is probably a product called 
"Comsol" an industrial solvent containing only approx 40% nitro and is inferior 
and considerably cheaper than Nitrofuel.

<    My after run treatment (every evening after flying): 
    
<    	- Restart the engine, to burn out the rest of fuel
    
<    	- Put some oil (good car oil does the job too) into carb, 
<    	  exhaust and crankcase and turn the prop a few times.
    
Car oil or Mineral Oil is not recommended as it is not soluble in methanol and 
can clog an engine. It is better to use an after run oil as mentioned in 
previous notes.

Re: .18
<        I have  two four-strokes, an O.S.FS20 and a Saito 45.  On
<        neither of them  is  it  easy  or convenient to get after run oil
<        into the engine because  the carb throat turns down.  And there's
<        no way to get oil into the crank case. Any suggestions?

Try removing the gloplug or putting the oil in the exhaust and turn the engine 
over  by hand.

John.

    Re .19 - when you order Red Max you can get it with castor oil and/or
    synthetic oil.  I think if you don't specify the type of oil they
    give you synthetic.  I don't know if this affects the color or not.

                                                             Bill

    I believe Henry's Hobby Shop on Franklin St. in Worcester carries
    Red Max.

    Hobby Barn II in Sudbury also carries the stuff and their prices
    are very low..
    
    md

    As a side note about fuel I was a the field last night and they
    were talking about Power Blast. Specifically that the order that
    the local hobby shop is presently selling will be the last Blast.
    Seems that it's not going to be produced any more. I don't know
    what fuel you guys in Eastern Ma. use but I thought you'd be
    interested.
    
    Tom

    
    RE: .-1
    I don't think that will break any hearts around here!  Power
    Blast has had a bad reputation for a few years, which may be
    why they're not making any more.  Most of the guys around here
    are using Red Max and Byron's.
    
    Bill

    Anyone have the phone number for FHS (suppliers of Red Max) handy??
    
    Thanks!
    jeff
    

    
    
    	Jeff,
    
    		For orders outside South Carolina, the number is
    
    				1-800-742-8484
    
    		and the FAX number is:
    
    				1-803-222-7285
    
    		Long distance number is:
    
    
    				1-803-222-7488
    
    
    
    		Carl

    For anyone interested, we just received another order of club fuel.
    Here are the details...
    
    	They currently are limiting club purchases to 24 gal/order,
    	regardless of the fuel mix.
    
    	They give a 5% club discount if paid in advance.
    
    	They ship via land carrier (not UPS) so someone has to be around
    	to receive the fuel.
    
    *****THE PRICES ARE GOING DOWN****
    
    We ended up over paying (as it took the treasurer some time to get the
    check sent) and they are sending a refund check!
    
    The cost came out to be:
    
    		12% ~ $10.75 (the club will charge $11 to make accounting
    				easier)
    		15% ~ $11.90 (the club will charge $12)
    
    Sorry, this particular order is only available to our club.  But if
    your club is going through a lot of fuel, it can be a great service to
    buy at club prices and sell it to the members..
    
    cheers,
    jeff