6 oz "Flywheels"
 

This is my first post to rcu so bear with me. I have experimented with flywheels for over a year and have found some very interesting results. Using the Ryobi as my test engine I have come up with 3 different "Flywheels" that work like the original. They are modular and use epoxy as a bedding material for the individual pieces and are held together with machine screws. These engines run from 1500 rpm to over 8000rpm on an APC 16/8 but seem to like a Classic 16/10 at about 7700 rpm. I have attached pictures of these "Flywheels" and have sequential pictures of the assembly process if there is anyone interested. I am not interested in manufacturing them but I believe that they are easy and SAFE enough that most guys can make them. THEY WORK! I have also made intake manifolds that locate carbs in front and behind the cylinders of 25 cc Weedeaters if someone is interested, they work also.

RE: 6 oz "Flywheels"
 

There was a guy a year or so ago who was making lite flywheels for resale.
He made his out of aluminum stock.

Unfortunatly they developed cracks after a while.

I do see that you are using a completely different approach.

Good Luck

RE: 6 oz "Flywheels"
 

profgigawatt: I like your data and photos. If you could PM me, I would like to get your phone number so I could call you. I am sure the people in China are at this moment working on a very lightweight mag that could be used on many of our small engines. That would eliminate on- board batteries and the expense of a electronic ignition. Good for us modelers. Capt,n:D

RE: 6 oz "Flywheels"
 

Lightweight mag?, china is probably mixing 1/3 glow fuel to 2/3 gas and selling a glowplug adapter to get rid of all the onboard stuff and using " NO INTERFERENCE " as a promo tag, but we know better.

RE: 6 oz "Flywheels"
 

These flywheels are aluminum. The flat disc on the "round cylinder" engine is cut from .500 x 2.0 aluminum stock. The two holes next to the magnet are from previous experiments, they will be gone with the next one. The balance material is set in a slot milled in the back side. It's pretty solid. The "conventional" flywheel is made of .250 x 3.0 aluminum angle and can be made as wide as one wants if strength is a concern. The only flywheel that "grew" on my when running was made of thinner aluminum. The "round" engine also has a considerable amount of potting material and iron cut away from the coil making the coil more than an ounce lighter. That complete system on the round engine is under 9 oz.

RE: 6 oz "Flywheels"
 

I am in China and we doing know work on fly wheels.

RE: 6 oz "Flywheels"
 

:Dbox car: Do they have any good Chinese Restaurants near to. :D

RE: 6 oz "Flywheels"
 

Hey yall, kinda on the subject, I carefully weighed one of my 30cc Homeys before and after conversion to electronic, and when you factor in the battery and the ignition box the savings was a mere 4oz. Looks like you might be able to match the EIs weight with with this type of flywheel--COOL!

RE: 6 oz "Flywheels"
 

You guys are keeping me honest. The flat disc system is about 9 oz because I have cut down the coil also. The only lighter ignition that I have used is the SAM (Society of Antique guys)Tim 's with hall ic and 3 nicads. The lipo was good only for a short time because the hall effect requires 3.8 volts and the lipo needed to be heavier than the nicads or hydrides. The 25cc weedeater (2 bolt case) has a TIM at 4.8 oz. w/ battery. The total weight of the engine ,muffler and ignition is 39 oz ready to mount including the aluminum intake. The 4 bolt case engine just came out of my KAOS spinning a 13/7/3 blade all torque and plenty of speed. Note the lack of a plug adapter on the 4 bolter. I drilled the head and put in a 3/8" npt aluminum plug (tapered pipe thread) tapped it 1/4-32 and used the micro plug. The engine doesn't know what plug it has and doesn't care. The 25cc"s have been in a Tiger Moth, PT-19, Kaos and GEE BEE. Sense I started building engines the planes are just a necessary evil so ARF's fill that bill.

RE: 6 oz "Flywheels"
 

With the GAS/GLOW setup and saving the most possible weight, is it really necessary to run a flywheel or EI, instead of mixing oil with your gas just add 1/3 glow fuel, it's easy, engine runs great and is very lightweight, is there some kind of advantage to run a flywheel, coil and spark plug that i'm missing.

RE: 6 oz "Flywheels"
 

I have an engine ready to try on Gas/Glow. I have drilled out the plug hole and installed a brass plug as I did with the weedeater in the previous post. The combustion chamber has thus been changed, it is flatter (i did not modify the plug, it is flat) and the compression has been increased.I believe that it is a homelite. I did run an engine on G/G after I found RCU and this forum and was semi successful and impressed but time is just now available to try it out. Too many things pulling in too many directions, all in good time.

RE: 6 oz "Flywheels"
 

How did you make those intake manifolds? Nice work.

AV8TOR

RE: 6 oz "Flywheels"
 

I like how you made that intake. Better than my Idea! Looks like you started with round stock (still round at carb) and then milled and drilled the rest. Sure looks nice! Capt,n

RE: 6 oz "Flywheels"
 

I think the flywheel absorbs part of the vibes from the power stroke or when engine fires. But a real heavy one is not needed. Only puts on more weight. Capt,n

RE: 6 oz "Flywheels"
 

Intakes; The intake that is to the rear of the cylinder is made intwo pieces, you should be able to see the gasket between the parts. The carb mount ring is drilled to the diameter of the carb as is the manifold. The manifold is bar stock and the machining is to lighten the unit. I drill the bar stock down the length of the manifold but not all the way. When I cut the opening for the cylinder end I radius the inside with a Dremel ball end cutter. The pump line is up to the builder, external is very easy. I have touched the manifold while the engine was running and not get burned, it was almost cool.
The unmounted intake is designed to mount the carb in front and across the cylinder. Built in the same way as the rear intake the front differs in that there is a plug in the front or back to create the seal as required, builders choice. The plug can be a press fit and held in be a pin or whatever.
I have encountered NO ill effects using these intakes, heat or otherwise. (You do realize that a prop extension is used on the front carb.) I have an aluminum manifold for a ST 51 carb to cylinder for the 2 bolt W/E. The ST carb worked as well as the Walbro on muffler pressure, here again no heat problem, it makes a very neat instillation. I can supply pictures of any of these items. It only took me two years to get on line!

RE: 6 oz "Flywheels"
 

The Capn' is correct. Your prop is the flywheel. We all have seen an engine throw a prop and scream like it's comming apart. It is a matter or preference as to gas or whatever. For my purposes, using a 16' prop, there is a definite advantage to a little flywheel. When I put the 25cc weedeater in my KAOS it required a spinner and three blade prop to clear the ground by 1/2" and provide enough inertia to idle. It still shook like crazy but It proved that a gasser can be used in a 40 size model "That was my purpose". The 18's idle well but the prop speed of a 6" pitch prop in the 7000+ rpm range doesn't give you the speed required for a heavier wing loading. For me it was a compromise between pitch speed at idle and stall speed at a given loading.
The gas glow sounds great but does it rust up the inside?

RE: 6 oz "Flywheels"
 

Captin, we cover 16 sq miles and not one restaurant.

RE: 6 oz "Flywheels"
 

Gas/Glow doesnt rust the inside of the engine, remember that gasoline has more lubricicity tham methanol, but if you want to be sure about it just perform the same routine as with yur glow engines "run it dry" and squirt if you want to some 3in1 oil or marvell's mistery oil.

RE: 6 oz "Flywheels"
 

I've heard of some problems with "3 in 1" oil so I don't recommend it. Marvel is fine, air tool oil is fine, I just use automatic transmission fluid. I have engines that are 20+ years old that still run perfect and have never been apart. After every session, I run them dry of fuel, and then inject a dose of tranny fluid and turn them over several times with the throttle wide open, and then I close the throttle. I do this with my Gas/Glow engines as well. Works great!

AV8TOR

RE: 6 oz "Flywheels"
 

I like air gun oil the best for my engines...but do it just like AV8TOR says.... turn the engine over several to get the oil ehere it does good. Happy New Year....Capt,n

RE: 6 oz "Flywheels"
 

I'm getting some 10-10 fuel tomorrow and mixen up some XXX. You know what's neat about this? I just ordered a new cylinder and a couple of rings for one of my engines. $38.00 setting on my door step. I can drop that engine into the Delta from 100 ft. and start all over again. This retirement is great!

RE: 6 oz "Flywheels"
 

Another option is to get a glow plug adapter for $9.95 from Horizon, and get a hot glow plug from them at same time. Use a good used cyl or same one on engine now and buy a Piston ring from Frank bowman. You then will only need one piston ring! That would save some bucks and the Bowman ring is the best. Right AV8TOR? Good Luck Capt,n

RE: 6 oz "Flywheels"
 

OK Captn' I have the engine. I'm going to use a 25cc weedeater "old faithful". It runs very well and flew my GP Tiger Moth great. This was my second conversion and it will eventually get the new cylinder. I over did some of the porting when I was tinkering with it, I can't leave things well enough alone. I guess that you break eggs to make an omlet. This one has the 1/4-32 threads for the spark plug without an adapter, it's been drilled plugged and tapped. The top of the cylinder has been cut down a single fins worth, enough to have the plug threads at surfice level inside the cylinder and recessed the top of the plug up to the ceramic. There's a picture of that engine somewhere in this thread showing the head. Four days of storm starting today in No. Ca., it's time to head to the shop.

RE: 6 oz "Flywheels"
 

OK so I go to the local hobby shop! $28 a gallon. Sticker shock, it's been 10 years. "Oil content?" What do you mean by oil content, is there oil in this fuel? "Earth to hobby shop, come in hobby shop" "Oil content, We don't need no stinking oil content!" Need I say more? Where's my glider? Now that I have tried it, the hobby shop experience was just a forcast of the joys to come! I may have to replace the thinner gasket under the cylinder. As measured by the crushed solder method I have about .025 clearence, factory is .050. "Look out, here comes your favorite propeller! Did I mention that my glowplug clip fell apart during this exercise and then the rain? Is someone trying to tell me something? I am not surprised by any of this, it is really kinda funny.

RE: 6 oz "Flywheels"
 

P.gigawatt: Read the data that Av8tor has come up with on the Gas/glow mix. Get some glow fuel for the big Supertiger engines. I think it 10/10 Ten percent nitro and ten percent oil. Then mix it 1 part of the 10/10 mix to 2 parts of pump gas. You then should have the right mix ...no spark ignition needed. Another way is to go to a speed shop and buy a gallon of achohol and some nitro and mix your own. You will need about 2.5-5 percent of Klotz oil for lube also. AV8TOR can fill in the details. I know it works. The only problem I had is not getting a slow Idle and my messed up 25cc Homelite seemed to vibrate bad. I do not know why??? I am about ready to try another type of ignition on it. Capt,n