It is commonly thought a plane flying is good, but a plane flying with a huge smoke bloom trailing it is better. In our hobby, diverse methods of inserting some liquid into the engine’s exhaust flow have resulted in a widespread variety of success. Glow engines seem to have the most difficulty in producing the wishful results demonstrated by the Blue Angels or Thunderbirds. Our hobby is moving away from the glow engine and towards gasoline engines. This trend has increased the desire to produce great quantifies of white billowing smoke engulfing the aircraft as it reaches the summit of the spiraling climb, and followed by the secular spin – all the time engulfed by smoke.
Wishful thinking? Not anymore! Some of the larger planes (in the 150-200cc) have two mufflers and can produce so much smoke during a 3D hover, the plane will disappear in the smoke! But are we satisfied? In a simple response: No! And the modelers said: “We want more.”
Most smoke generating mufflers consist of a ‘pressure’ fitting – the same fitting we use on a glow engine muffler to add some pressure to the fuel tank. (https://www.dubro.com/products/bolt-on-pressure-fitting SKU: 241)The fitting is simply a hole surrounded by some metal that can be secured to the muffler. Attached to this brass fitting is a tube that comes from a pump of some kind which in turn to connected to a bladder containing smoke oil. When the pump is turned on, the smoke oil is injected directly into the muffler, which in turn heats up and produces smoke. The inserting of oil is in the form of a stream and not all of the oil can be heated enough to be turned into smoke and sadly expelled out the muffler and all over the bottom of the plane. If there only was a way to “burn” MORE of the oil. And the modelers said: “We want more.”
Some modelers have used brass tubing that is pinched or crimped at the very end to spread out the stream of smoke oil, but with varying degrees of success.
Another method is to pre-heat the oil before it gets injected into the muffler. Some modelers have wrapped soft copper tubing around the cylinder head or the muffler itself before being injected. That helps for sure, but still the modelers said: “We want MORE.”
Well maybe the shouting can be turned into smiles as a relatively new product has entered the arena in the form of an Atomizing smoke oil injection nozzle! This product is the brainchild of Harlan Reiner who resides in Isanti, MN, and yes this product is part of a ‘cottage’ industry (meaning he works out of his garage or basement).
Harland must be some sort of engineer because he HAS come up with a solution and it is not a special muffler, smoke oil or other pre-heating method to produce more smoke! His idea was to produce smoke by sending a MIST of oil to reach the heated exhaust thereby permitting more oxygen to ‘smolder’ the oil and producing more smoke. He called his invention “Atomizing smoke oil injection nozzle”.
Just dumping a stream of oil into the exhaust chamber only permits some of the oil to be turned into smoke while the rest is wasted (and coats the bottom of the airplane). He not only designed (using CAD) and machines these nozzles but has now made them available to those modelers who keep saying “We want MORE.”
Harland’s nozzles are precision machined from one solid piece in either stainless steel or grade 2 titanium and use 10-32 thread patterns and DO NOT require welding, soldering or any other method to be mounted to any muffler or canister! He also has nozzles specifically for turbines! According to him, he even uses a microscope to check each and every nozzle! And yes, they are made right here is the good ole USA.
He also has another product called a “no-weld kit” for adapting smoke nozzles onto various header pipe sizes for use with canister style exhaust systems simply by drilling a hole and bolting them on. He even makes turbine smoke tubes for our turbine powered flyers using the same style Atomizing nozzle tips. Harland can be contacted via email at email@example.com or on Flyinggiants.com where his user name is “crankcase”. Harland does not have a website yet, but indicates he is working on one. He is registered on rcuniverse.com under username “doublestroken”.
A little research found that he has been producing these nozzles since the middle of 2016 and has sold these world-wide. NOTE: I have no obligation or alternative motive to do this review, just a happy customer!
I wrote to him a while back as I had some questions and here was his reply:
The Nozzle kits include 1 nozzle, locknut, safety wire, logo sticker and installation instructions cost $20 each and I personally feel well worth the money.
A Test: I did a little test to compare the amount of smoke produced with two products: 1) a smoke muffler commercially sold and, 2) Harlan’s Atomizing Smoke Oil Injection Nozzle. The test bed was my Hangar 9 RV-4 using a DLE 35RA engine. The stock DLE35 muffler was fitted with Harland’s nozzle and I added a short run of copper inside the muffler to ‘preheat’ the oil because the smoke muffler that was purchased had that feature also. Pictures were taken when we felt the smoke was the best. I will let you decide which produced more smoke!
Yes, Harlan Reiner has made a better mousetrap with his “Atomizing Smoke Oil Injection Nozzle”. It is simple to install and produces more smoke than the standard pressure nipple more commonly used. Some may question how much MORE smoke is produced with his nozzle and for that I don’t know of any guidelines or standards to compare one product to another but one fact remains and that is the amount of oil used is much less than any product on the current market that I’m aware of.
These nozzles cost $20 each and $5 shipping in the CUSA. Harland’s email is: firstname.lastname@example.org
Very little oil residue left on plane.
Low smoke oil consumption per minute.
I averaged 2.5oz./minute of oil vs. 8.8 oz/minute with smoke muffler.
If you do a tail slide, you will get a misting of oil all over your plane