AMB

we guys a box is on the way with 4or 5 drone 29s to me from my bud in NC lots of pcs dusty, gummy guess it all goes in a can of kero for a few days, he thinks the needles missing
but should be able to find a needle valve assemby that will fit suggestions welcome , rods fix a must egged out martin

he thinks he has a Cox 09 in there also that would make an interesting conversion to diesel

[email protected]

Martin, my strongest running Drone BB has an egged out rod. The other tthree do not. Different serial numbers have different exhaust duration. At least the four I have. Two with 11XXX serial numbers most exhaust duration and highest RPM. Two with 13XXX less exhaust duration and less RPM. I use Aerodyne variable compression heads. Are your's the first or the later BB version or a mix? Jack

AMB

Jack I will not know till I get them and let you and the others know the serial numbers . Would be nice to get an areodyne head

earlwb

There are quite a few needle valve assemblies that should fit the engines just fine if you are wanting to run them.
I have forgotten the name of the brand of aftermarket needle valve assemblies they used to sell way back then. They fit quite nicely when you find one.
But a Fox control line needle valve assembly doesn't work bad at all either. One could make their own needle valve assembly too. it isn't really all that difficult, if you have a lathe.

The engines tend to clean up easily enough, nothing really fancy inside. The second model with the ball bearing in it uses a standard size ball bearing that is easy to get. There may still be some rods around that one could get, but it isn't terribly difficult to make a new rod though.  Nowadays we use normal model engine diesel fuel which is ether, kerosene and oil. In the early days they ran straight ether and mineral oil. The mineral oil helped to moderate the harsher combustion of all that ether, which of course is why the rods or bushing on the crankcase wore out some. But with our modern diesel fuels, this isn't a problem of course.

For control line the engines used a 11x9 or 11x10 prop. The engines don't turn high RPMS so you need to use a higher pitched prop to get the speed up. Since the compression is fixed, you choose a prop that works well with the engine. My engines tend to run well with a 12x8 or 13x6 prop. The 13x6 results in a good engine run and the 12x8 results in the engine being just a touch under-propped.

AMB

Well group the drone stuff should be here tomorrow the one good one is still lurking a way up there, he is still looking been 65 years since last run martin

AMB

OK guys the stuff s here the drones will require some parts needle valve , only have back plates no tank no screws , rod seems ok crankcase#1339 AND 2951, ONE SHAFT MISSING

THE McCoy 35 red glow in very good condition no slop and good compression alos not in pix a McCoy 19 appears ok shape (glow) nad a cox 049 basket case and remnents of an OR 19 ?? martin


note both drones have screw in venturi

earlwb

Ok they are the early model engines circa 1947. Bushed crankshaft, no ball bearing to support the crankshaft. In 1948 the second version came out and it used a single ball bearing to support the crankshaft.  The 1947 version also had the screw on venturi whereas the 1948 version had it cast into the crankcase front.  Both types of engines are fairly easy to refurbish into running engines. With the screw on venturi one can make an adapter for a RC carb if they so choose too.

Of course they only rev up to around 6,000 RPMs or so, so there isn't much of a throttle range to them.

earlwb

Here is a pic of one of mine with the fuel tank on it







Here is another one







and here is a Ball Bearing 1948 version

AMB

Earl the pix are great, both of mine have the screw in venturi carb, missing needles on both and screw on venturi on other the cup shaped back that goes under the backplate screw missing on both only one diesel head and no rear drive washers martin

earlwb

One thing to double check is the screw in venturi.
When I made my RC carb  adapter, I used the venturi off of one of the engines to measure for the thread size. Much to my surprise it was the wrong thread size. So I measured the threads in the crankcase and used it to make the adapter. I had not noticed the screw in venturi was only going in a little before the threads started binding up.  Anyway the RC adapter worked good once I made it with the correct threads on it.

The OEM venturi is  on the left and the incorrectly threaded venturi is on the right. Fortunately the person who made it didn't mess up the threads in the crankcase.

AMB

Both mine early plain bush no BB serial numbers 1399 and2951 shy a crank too martin

and only one diesel head other is glow

earlwb

Yeah the drive washer can be a bit time consuming to make. The last time I made a D hole shaped drive washer, I first drilled a hole undersized in a long chunk of aluminum rod then I used some hand files and filed it out to fit OK. Then I put the rod in on my lathe and shaved off the outside to make it to size and make it not wobble. The other method just uses the lathe to do it and move the cutting tool in and out back and forth and just use your hand to rotate the chuck on the lathe as needed.  The factory likely used a broach to make the holes with in the drive washers. But a custom made broach is very expensive. A punch would have deformed the aluminum too much. Modern technology would have likely used a CNC controlled water cutter tool.

The crankshaft is fairly simple too. One could make one if they want to. The Drone engine doesn't have anything fancy to the crankshaft. It just uses a good piece of steel for it. I don't even think they hardened it either.  The connecting rods look like they were hand finished using hand files too. So even those aren't all that difficult to make.

I do have a Drone engine casting set I got from Davis Diesel Development. I plan on making my own Earl-Drone one of these days. The thing that held me up is drilling the three through holes in the crankcase for the screws to bolt the front on with. The metal isn't all that thick around the holes and the holes have to be straight. So I need to study and practice the techniques for drilling little holes deeply and straight first.

ffkiwi

Martin there are some Drone parts on Ebay at the moment that may be useful to you-including a crankshaft, needles ,gaskets and screws in a job lot. See listing #321056868693. Current bid is reasonable. Vendor is in Canada.

ChrisM
'ffkiwi'

AMB

THX will check it out martin

AMB

just checked E bay no back cover does have needle screws drive washer have to think on this one martin

earlwb

I took a look at the parts on that ebay auction and the crankshaft looks like a ball bearing 1948 version. The needle valves are nice. The gaskets are pretty neat but I would likely make new gaskets instead of using the original ones in their packages.  That does have the glow plug head in the pics too. It does have the drive washer though.

AMB

Earl will have to check around for the "cup" ( backplate), the screws I would guess are US not metric, making gaskets no big deal, so will pass on what is offered

best regads martin thx for your great input on the drone

earlwb

I thought it was a odd design like that with the clamp on backplate arrangement as used in the earlier Drone engines. But quite a few other engine designs did the same thing too. Maybe it was cheaper to do it that way at the time. I think they used to just stamp them out of metal at the time, so maybe it was cheaper, as there would be little to no machine work needed if they were stamping them out. But you could machine a backplate for it using a lathe if you have access to one. The backplate itself is fairly simple in that regard.

But vintage O&R engines and some other brands like it, used to dispense with screws, as well as drilling and tapping holes altogether. They used to spot weld the cylinders onto the crankcase, plus they even went so far as to swage on the heads onto the cylinders too. It did help reduce weight a lot, but it made it very difficult if one ever wanted to repair a engine though.

AMB

Well my bud in NC found the missing drone intact, complete with prop still on it he had sent me some engines bits and pieces OR McCoy, and drone parts, should have in a couple of days
it went missing in his stuff for 50 years+ , think will try the 1/3rd /1/3rd 1/3rd mix as a start when it shows in a day or two martin

earlwb

I suggest getting a can of commericlally made model diesel fuel for your first experiences with diesel engines. Then you have a reference point to use for mixing your own fuel. That way you can be reasonably sure the fuel is good if you have problems.
Davis Diesel Development and Dr Diesel both sell the fuel.

The problem we have is in obtaining ether. Since the illegal drugs people got involved, ether is now quite difficult to obtain.  The best substitute is to get John Deere branded starter fluid, as it is mostly ether in the can. Other brands of starter fuild may contain little to no ether in them.
Anyway trying to figure out the mix ratios with the starter fluid can be a problem if they say it contains between 5% to 50% ether for its ingredients.
Thus the John Deere brand is easier as it is typically 80% ether.

AMB

Earl I do have a good supply of DAVIS ABC blend guess we can try that first I was thinking the Drone would require a higher ether %
then " do not count your chickens till they are hatched" do not have engine yet so do not know condition martin

fiery

My Feedback: (2)

Martin

As an iron + steel, non-ball raced diesel engine, this early Drone would probably do better on Davis Diesel 1/2A spec. diesel fuel.

I am sure the manufacturer specified a fuel having an oil content of 25% of something like SAE 70 weight monograde motor oil, with the balance of the fuel mix being ether.

They do run on more usual mixes with kerosene/K-1/Jet A-1 as the power base.

Some really useful information on running Drones may be found here:

http://controlline.org.uk/phpBB2/vie...ighlight=drone

Regards

earlwb

Mine ran Ok using regular Davis Diesel fuel with some extra castor oil added just to be safe. But if the engine has been run in good, I don't feel that one needs to add extra castor oil to the fuel. They maybe would have run better using the original Drone fuel mix of 75% ether to 25% mineral oil though. But I felt the original mix is a bit harsh on the engines.  You have to use mineral oil, no synthetic and no castor oil. The mineral oil moderates the extreme combustion effects from using straight ether. The other oils don't.  But using a mix with more ether, along with kerosene and oil isn't a bad way to go either.

AMB

will add some caster 4 -5% to the ABC fuel and give ir a try martin

earlwb

Here is a video clip when I went to see how much noise it outputted. Since it turns a little over 6,000 RPMs I figured it would be fairly quiet. The DB meter was reading around 85 DB or so. It seems a little bit under compressed with a APC Scimitar 12x8 prop, and a 13x6 prop is just about right.
I was using Davis Diesel Development fuel. Actually I was thinking at the time that the slight miss with the 12x8 prop gives it some character like it was an old time sparkie gas engine.

[youtube]http://www.youtube.com/watch?v=nTbJcE61aLU[/youtube]