JR SATAN Build

I can Stunt and do Combat with this Tank?? Its a weird set-up that this kit has with the Tank...It goes over the cylinder head down underneath!!

One thing to keep in mind is the positioning of the tank. In other words, the pickup should be exiting at the centerline of the leading edge. The problem with using the wedge they're telling you to use is that it has been modified. This was common practice back in the day and they also show similar plumbing changes to the Veco tank Goldberg tells you to use in the Voodoo. Keep in mind the Perfect tanks were far from perfect. When burying a tank inside the plane like the plans call far means you can never access it unless you cut it out later.

When you do finally settle on a tank I highly recommend using a 5 oz. syringe and inflate as if your trying to pop it. This is to be done underwater. Here are the problems your going to be faced with. Perfect used brass tubes in all their tanks. Copper is the only tubing that should ever be used. It doesn't work harden itself like brass does nor does it corrode like brass does. Ever see all that green goo on a Cox fuel nipple? The tubing is not seamless and is prone to splitting. This can even split if the tank is new but unused old stock. The other problem with the tanks is the fact they didn't internally solder the pickup to the outboard corner of the tank. This will act like a tuning fork inside and will eventually fail. May not do it right away but it will. These tanks were soldered on a hot plate using low heat and poor quality solder. Vibrations is the death of solder. Checking all tanks is a good practice. I go as far to resolder the Pittsburgh seam which is the seam on the back of the tank the one that runs horizontally.

In the build drawings, they remove the overflow pipe out the bottom of the tank. Reason for this is that you have no gear and you would inherently snap it off the bottom of the tank in one landing. It should be removed and also filled with solder. The pickup on the stock tank is exiting centerline of tank. This means it will need to exit your leading edge on the centerline which means you would have to drill a hole through the leading edge. I don't recommend this and would reroute the pickup by exiting through the top or bottom of the tank rather than out the front. In the pic of the drawing your seeing the fuel line going up and over the cylinder. This typically isn't a problem due to the actual pickup where it is picking up fuel is the same level as the engine centerline. This could have a rearward siphoning effect back into the tank initially but shouldn't be a problem once running. You would fill through the fuel pickup and the fuel will run out the overflow on the top. The top vent goes to the bottom of the tank so this would need to be unsoldered and raised to the top. This is quite simple and gives you lots of experience with tanks once you do these mods. It's quite easier to do this initially with a new tank rather than a old one. Either or the metal has to be absolutely clean and rosin core solder used and good quality soldering iron followed by a acetone or laquer thinner wash. This is a must as the flux will cause corrosion.

I never EVER assume a tank is good. The Brodak tank of the same size would require some slight mods as well as in the venting that I discussed above. To answer your question, the tank will work but it will require some modification. In hard maneuvers though there may be a possibility that your fuel will run away from your pickup. This will cause a leaning out condition that will either kill the engine immediately or make it run inconsistent until the fuel returns once again submerging the pickup. This is why combat is flown with bladders rather than hard tanks. Reasons for me not liking the wedge tanks is due to these problems. I use them in stunt all the time. They work great for stunt but remember, the speeds and g loads on the fuel are not like a 7-8 oz wing going 80-90 mph and snapping into a wingover. Sometimes you can compensate this by setting the engine off richer than normal. Although, speed is going to be greatly sacrificed.

Another thing to keep in mind is that it doesn't hurt to try and cant the rear of the tank inside the plane slightly to the outboard side. As the plane is flying in a circle, it's not always flying tangent to the circle. The plane if yawed out slightly to the right due to engine offset or leadout position will not correctly place your fuel load on your pickup. It doesn't require much of a cant outboard but placing it square to your leading edge could cause some problems especially towards the end of the flight. Steering the tank out say 1/8"-1/4" would certainly help. Ken

Shawn,

Great bit of info, it will help me a great deal. Thanks for taking the time to write that.

Ron

I just clicked on the link to the Brodak tank above. The Perfect version in fact does have the pickup exiting out the front of the end cap. I have one here that is older than dirt. The Brodak version has it exiting on the side. This is what I was trying to explain above about rerouting the pickup. Both vents would still need to be addressed. Ken

Great info... Thank -You!!But I still do not understand the modifications your doing to this tank. A diagram is needed for me to understand constructive alterations on material items. It's like trying to talk a guy down, landing a Jet from 27,000 feet, he might get it rite..chances are he wont. Maybe a bad analogy but the information looks to be important and I just don't get it.

I have to say, you cracked me up with your statement. I will try and get some pictures. My son Shawn is much better at the computer than myself. I will try and show you some of the problems I've been faced with and how I resolved some of them. I believe I do have some examples. I do have a picture of the plans from the Voodoo that does indeed show the mods right on the drawing. Whether it's big or small it all works the same. I'm very interested in your build and would love to see pictures as well. You don't see these flying. I've been into control line for a lot of years and this plane in particular for some reason just didn't gain the popularity it deserves. I guess the .15 size ships were kinda of caught in the middle. It was probably not much more to go buy the Voodoo. Most flyers at the time more than likely progressed from the 1/2A scene right into the Fox.35 stage. No one engine had more plans drawn around it than the Fox.35 in my honest opinion. What makes it frustrating is that when you copy the plans to the letter and it doesn't work very well. I've been there. There is a lot to learn and what makes it all the better is that we can share our thoughts and opinions. Ken

There is also a Super Satan that was a Golberg/ Scarinzi plan that never hit the market to the kit stage.


Here is the Plans to the Super Satan!!

If you go to this link ...you will obtain much more options to address your modifications Shawn..There are set-ups with chicken hoppers and tanks that need soldering...the plans on the Jr.Satan do specify the 2oz #9 Perfect tank so deviating away from that tank suggestion too far will not be in the plans for my build....we can solder up different tubes and pickups in that particular tank but a lager tank will not fit in the specified place. Very interested in your modifications to these tanks and a little trip down memory lane. I will be posting step to step procedures in the build as I go... open to you guys to criticize and ridicule...I have my Flame suit coming back from the dry-cleaners!! http://brodak.com/fuel.html?p=14

My Lil' Satan has the tank supply tube exiting through the centre of the leading edge, this hasnt caused any problems so far, and I've whanged it in to the deck several times.
I glued a piece of 1/16" ply to the inside of the L/E before I drilled it for the tank outlet.
The Lil' Satan was never supposed to have a separate tank, you were supposed to use the engine's own tank, but I don't really like Cox integral tanks for C/L so I modded it a little.



Back in the day, most .15 combat wings used a fuel pipe through the L/E without any detrimental effects, it doesn't weaken the L/E to any great extent, and usually the front of the tank was epoxied to the L/E anyway, so it was probably the strongest part of the model!

Not to burst your bubble or disagree with your building knowledge in any way, shape or form, but the building plans on the the Jr.Satan specifically state not to route the fuel line through the Leading Edge. There has to be some pupose to this!!....Shawn Cook, a previous responder to this thread aswell as the building plans, (Carl Goldberg), both state that the L/E is a NO-NO for fuel line routing. Further investigation to this matter is under way.

Well the inside bit of the Wing is the weakest so I suppose they just don't want it to be made any weaker.

Heres a cool mod without the use of solder or a level of difficulty!!
http://www.aeromaniacs.com/busholator.htm

For starters, the wedge and it's design is proven and it does work. I never said it wouldn't I just said that it has it's limitations. The Lil Satan above is a great example. Yes it works, but in the event you were to put this through hard maneuvers the fuel can run away from the pickup. Reason for this is the fuel and the pickup is all the way on the far right. The fuel not only has to travel a longer distance to get to the pickup, centrifugal force is acting on the fuel as well. The solution to this is to move your tank inboard. That would mean burying the tank inside of the nacelle area directly behind the firewall. This may work for the Sure Start but I can assure you when it comes to a Tee Dee somewhere in the flight the plane is going to suffer. I have a perfect example in a picture I'm going to provide. This is the reason to run crankcase pressure. Crankcase pressure doesn't give the engine any more power than what it already has. What it does do is allow a constant fuel supply to the engine in these hard maneuvers and can also allow for a larger venturi which can overall give you higher performance over the stock setup. You can open the venturi hole in a Sure Start to such a point and then the engine won't effectively run correctly. Why, the engine can longer draw fuel due to having not enough vacuum pressure to draw it. Tee Dee's are also very critical to tank height. My experience with the leading edge is not to penetrate it. Yes it is the best place for the pickup, but it will weaken it and it also becomes prone to fuel seeping into it. My advice is that if you can avoid it try and do so. I know this isn't always an option. The closer you can get the tank to the engine and the shortest direct route to the needle is the best. In fact, a good trick in a standard vent tank is to just cap one off and leave one open. The other problem with a standard vent tank is the fact it leans out during the whole flight. When the tank is full and the head pressure is there the engine runs slightly rich, as the level drops not only does the engine speed up so does the plane. This is the point that the engine is now starving for fuel. My goal is to avoid these problems. Ken

The Super Satan was designed by Larry Scarinzi. I know Larry personally and he thoroughly enjoys watching my son Shawn fly. I've gained a lot of knowledge from the senior flyers. Larry is legendary and he's had a lot of input for high powered combat engines through the years. I'm not here to attack anyone I just like sharing what works and what is problematic. I'm having problems currently. This is why I'm asking questions myself in other posts concerning crankcase pressure on Cox's. I'm going to try and post some of the planes and tank designs and will take it from there. Currently like I said my club member has a Jr Satan which is undergoing repairs but will have a Medallion in the nose. Ken

Thats exactly what I'm putting in for power aswell.Medallion .15. You are correct about Larry Scarinzi/CarlGoldgerg..they designed it and it's there for the making. Thanks for the responses Ken and glad to hear your not going " Charles Manson" on the boy's in the Cox Forum...worried there for a minute. Lokk forward to your pictures and advise.There's a post started about the Meadallion side nipple in here....guys have alot of input on this issue...one is that it does not work and when it does, not very well..a real PITA .

Shawn provided some pictures. The cream colored plane is a Dumas baby Tomahawk which is my most cherised 1/2A. If you look, right where the pickup exits the leading edge, the Monokote is split over the top of it. This broke right there several times. My solution was to remove the tank which is siliconed in and splice a piece of 1/64th ply to the back of the leading edge with a hole in it for the pickup to pass through. So far it hasn't broke. I've done it several times and my goal is to avoid these mistakes. The other plane in the pics has it going through as well. Difference on the clear silkspanned plane is that I put the 1/64th ply on the back first. The picture of the tank shows the plug and patch where the fuel pickup used to come out the front of the plane. The pickup is now on the bottom of the tank after I re did the plumbing. Had I done this first, the leading edge never would've broke and this is my solution from now on. The smal bibplane is a Larry Scarinzi Queen Bee powered by .020. I was going to have Larry sign it last year. The plane is covered in Jap tissue and clear dope. It's becoming a bit oil soaked actually. This plane is highly maneuverable and if the tank was large enough will do the entire stunt pattern. Great flying plane and faster than you would think. The picture of the Tee Dee with the steel rule on it is a Top Flite Combat kitten. I placed the rule on the wing to demonstrate to you when I'm talking about the relationship of pickup to the needle valve. From the edge of the rule to the needle valve there's about 5/8" that the fuel has to travel to the left to get into the engine. Believe it or not this engine will not run due to this problem. It will run and fly fairly slow but forget leaning it up and maneuvering. This goes totally against what the fellow above states about his Sure Start and Lil Satan. The problem is the tempermental Tee Dee and it's difficulty with fuel draw. If the tank was moved another 5/8 to 3/4 to the leadout side of the plane I feel the engine would work. Obviously this is difficult to do now. I did try crankcase pressure and it failed miserably. I should've made a compartment inside for a pressure bladder. I may just do this as I run bladder all the time and it just works and is also lighter. Ken

I certainly would like to know the fellow by name who's been running the Cox's under pressure. I'm not trying to sway from the original topic. All this above was required to explain the relationship from tank to engine within the build. I posted some pics earlier this month about the Tee Dee on a pipe. The engine in the plane I posted is a .051. I can't get this plane to work and it's driving me crazy. It will start but since it's so cowled in it overheats immediately. The Combat Kitten above has the side nipple drilled for crank pressure. The engine surges up and down in rpm and is completely radical. There's no airleaks in the system I checked a billion times. I also have a 128 tpi needle in it. I believe the engine has my Tee Dee carb body fix on it as well. You can see the brass piece directly under the needle valve assembly It's a piece of K&S 3/8" brass tubing cut and filed to the shape of the body and epoxied on. This is how I fixed all my carb bodies prior to the new ones being made and the ones that Mike Parkin provides on Ebay. I want this Combat Kitten to work. I will say this, the best engine I ever used on a Kitten was my best running Black Widow. The poor engine ingest the snap ring. I switched to the white reed I believe this is a Teflon reed. I received it from Davis Diesel. Well in the package, two were stacked right on each other perfectly and I didn't see it. The snap ring never engaged properly into the groove and it just destroyed the engine. I will have to take a picture of what it did to the case. The snap ring almost came totally through the case. Unbelievable actually. Anyone that has any advice to give concerning my Tee Dee setup above I'm all ears. I will try and keep it short and to the point so I'm sorry for the rambling. Ken

The guy running the Coxes on crank case pressure is named Bob. That's me. I have a Sig Hummer with a Tee Dee running on crank case pressure that I will try to post some pictures of this weekend. It is really a very simple and dependable set up. The only difficult part is getting the needle set the first time.

Also, if I get a chance (it is my daughter's birthday this weekend) I will post a pic or so showing a typical set up out of the plane.

Bob

fit90 wrote:The guy running the Coxes on crank case pressure is named Bob. That's me. I have a Sig Hummer with a Tee Dee running on crank case pressure that I will try to post some pictures of this weekend. It is really a very simple and dependable set up. The only difficult part is getting the needle set the first time.

Also, if I get a chance (it is my daughter's birthday this weekend) I will post a pic or so showing a typical set up out of the plane.

Bob

Hey Bob,

I too have a hummer, I run pressure of the supplied tap on the TD. Is this what you are refering to?

Would love to see some pics.

Ron

This leads me to another gas tank question gentle men... Can I put a gas tank of my choice into the Build? I know that i am restricted by space...but other then that ..why not use a 3oz tank?...would a rectangular tank be better then a wedge tank?? Thanks!

ZACATTACK wrote: This leads me to another gas tank question gentle men... Can I put a gas tank of my choice into the Build? I know that i am restricted by space...but other then that ..why not use a 3oz tank?...would a rectangular tank be better then a wedge tank?? Thanks!

Don't see why not. The clunk should compensate. 3oz may make you a little dizzy......

Ron,

I will post in the "starting a pressurized cox thread" so as to not hjack this thread any more.

Bob

My Templates and other items are coming this week..I will be building %80-%90 of this Combat Trainer by scratch according to the old plans..some modifications may be done for structural integrity...most balsa is already purchased and the leading and trailing edge are complete. This build will have Pictures accompanying the steps and the members are welcome to put in there views as long as your nice about it...Going to try to produce a build thread so a member will be able reproduce this Combat Classic at home...The Jr.Satan Lives & Breaths in 2012