.098 V twin using 2 Cox .049 Cylinder assemblies.

[argat1]

I am absolutely new to this community! I came here in search for info regarding the construction of an engine using a V twin configuration. I have several Cox .049 engines. Recently, I saw a home made simple of what I want to build.

Is there somewhere a set of plans and info regarding this subject?

I, of course, will appreciate all the posible help anyone can provide me with.


Ar.

 

[Tin Falcon]

interesting question.

a v twin recently sold on e-bay and there is currently a radial 3 for sale out of italy so $22 ww shipping.

3 cylinder cox engine
Tin

 

[cidrontmg]

There's also http://www.jamesengine.com ,especially the HEX-2, HEX-4 and Cox V-4. Drawings are included (free!), and there's also HEX-2 plans, published in Model Engine Builder Issue #9, HEX-4 plans were published in Model Engine Builder Issue #14.
There are also Italian designs, 3- and 5-cyl. radials, but I don't think there are drawings, or plans, just the fully and ready assembled engines. Nice interesting engines.

 

[stevehuckss396]

I have 2 of the Hex-4 engines. One was bar stock and 1 was built using the casting.

I also built a 9 cylinder but have not started it.

I also designed a 5 cylinder radial but have never built it.

 

[DICKEYBIRD]

I can't tell from the pic Steve; do your radials have individual engines geared together or 1 crankcase with a vane type blower like Ralph Barnette's 5 cyl radials? (R.I.P. Ralph, we miss you.)

Those look awesome! I've got boxes & boxes of Cox stuff squirreled away but never got around to making a multi. One of these days....

ps: That 9 cyl. will take some heavy duty wattage to light up 9 glow heads!

 

[stevehuckss396]

I can't tell from the pic Steve; do your radials have individual engines geared together or 1 crankcase with a vane type blower like Ralph Barnette's 5 cyl radials? (R.I.P. Ralph, we miss you.)

Those look awesome! I've got boxes & boxes of Cox stuff squirreled away but never got around to making a multi. One of these days....

ps: That 9 cyl. will take some heavy duty wattage to light up 9 glow heads!

It is a single crankcase with a blower. I traded emails with him many times during the design phase of the project. I had no idea he had passed.

The wattage is the biggest reason I have not run the engine.

 

[DICKEYBIRD]

It is a single crankcase with a blower.

Wow, that's fantastic! Do you have any pics of the crankshaft & master rod setup? I'd love to see how you did that!

As far as the plug driver, I'll bet there many on the forum that could draw up a simple circuit to supply 20-25 amps @ 1.5V. You'd need a couple good ebay buys to keep it reasonably priced though. I guess the easiest way would be to strap together 9, 5ah NiCds with individual leads. Years ago, a friend gave me a box of old Anton Bauer 12V videocam packs and I was able to cut them open and pick out the cells that were still good. Those things were great for starting Cox engines.

Yes, I miss Ralph; he was a unique & talented fellow. He passed in early 2011 if memory serves. I used to run into him every year at the S.M.A.L.L. event in Little Rock and we talked at length about our projects. He showed up one year with a tri-motor with 3 of his 5-cyl. radials on it. What a sound that thing made!

He lived only 40 miles from my me but I never got around to visiting his shop. I was heavy into Cox powered r/c model aircraft design/building/flying at the time and and didn't do much machining. By the time I got heavy into machining & learned enough to be able to ask intelligent questions, he was already having health problems.

 

[argat1]

interesting question.

a v twin recently sold on e-bay and there is currently a radial 3 for sale out of italy so $22 ww shipping.

3 cylinder cox engine
Tin

Hi Tin,

Yes, in fact that engine on which I was bidding got off my reach because my cell pone died on me and I just couldn't enter a higher bid. I was away of my computer too. :wall:So, I decided to make miself one like that to start my way in this amazing world of building an engine that Works.

Ar.

 

[argat1]

There's also http://www.jamesengine.com ,especially the HEX-2, HEX-4 and Cox V-4. Drawings are included (free!), and there's also HEX-2 plans, published in Model Engine Builder Issue #9, HEX-4 plans were published in Model Engine Builder Issue #14.
There are also Italian designs, 3- and 5-cyl. radials, but I don't think there are drawings, or plans, just the fully and ready assembled engines. Nice interesting engines.

In deed they are nice! The Hex 2 looks very apealling. The thing that always makes me wonder is the heat treatment for the crank cases. I have no way or means to do that.

The other design that uses the engine's own case look nice and more... "flashy" but I wonder if the wight-power ratio is worth the pain.



Ar.

 

[argat1]

I have 2 of the Hex-4 engines. One was bar stock and 1 was built using the casting.

I also built a 9 cylinder but have not started it.

I also designed a 5 cylinder radial but have never built it.

Steve,

I love the 9 radial!

Have you ever mounted the Hex 4 on a plane?


Ar.

 

[John Rus]

I have 2 of the Hex-4 engines. One was bar stock and 1 was built using the casting.

I also built a 9 cylinder but have not started it.

I also designed a 5 cylinder radial but have never built it.

PM sent.

Cheers,
John.

 

[stevehuckss396]

Wow, that's fantastic! Do you have any pics of the crankshaft & master rod setup? I'd love to see how you did that!

The master rod is a Cox rod silver soldered to a machined part.

The crankshaft

Drive shaft for the blower

 

[DICKEYBIRD]

That's incredible Steve, thanks very much for the amazing pictures. Too bad my best ol' flyin' buddy Brian Pate's gone on to a better place. He'd be havin' a fit after seeing those. He loved Cox engines more than anybody I've ever met.

 

[deverett]

There appear to be 2 types of Cox 049 cylinder: one type with single wide exhaust ports and the other with twin narrow slot exhaust ports. Does it make any difference which type of cylinder is used on these types of engine?

Dave
The Emerald Isle

 

[DICKEYBIRD]

No difference in performance from the different exhaust ports*. The single opening style cyls. were the earlier version before reports from customers of fires occurring when priming/starting them caused Cox to first add screens across the exhaust ports then change to the twin slot port system. (In the 80's if memory serves)

*Unless you want to talk about the effect that sub-piston induction/free porting has.

 

[deverett]

Thanks for that explanation dickeybird.

Dave
The Emerald Isle

 

[petertha]

As far as the plug driver, I'll bet there many on the forum that could draw up a simple circuit to supply 20-25 amps @ 1.5V. .... I guess the easiest way would be to strap together 9, 5ah NiCds with individual leads. .

Ive often wondered why that low tech, dedicated 1.5v Ni* battery 'per glowplug' wouldnt be a good cheap solution. Are NiCds even sold anymore? Even NimH are getting harder to find these days.

I thought a programmable RC BEC-type regulator might work, but I think their min output voltage is ~ 4 - 5V.

From a battery standpoint, Lithium (polymer or LiFe) are dirt cheap & can handle the amps with ease. The challenge is matching plug voltage vs nominal cell voltage. My knowledge of step down regulators is zilch.

Could a 1S Lipo battery like this (3.7-4.0v nominal) be dedicated to a bank of 3 plugs in series? (3.9v/3 plugs = 1.3A/plug). Its good for 88Amps.
http://www.hobbyking.com/hobbyking/store/__18559__Turnigy_2200mAh_1S_40C_Lipoly_Single_Cell_.html

Sorry for the tangent. These Cox engine assmeblies are awesome. I love that 9 cyl radial! Yes, this plug driver problem must be licked so we hear can that baby run!

 

[deverett]

I fancy building the Hex-4 from barstock.

Does anyone know of a source of the cylinder/crankcase tap? Size is 17/32" - 40. Googling doesn't bring any results. I've contacted Cox concessionaires but they don't sell them. I've contacted James Engines and he doesn't have any. Specially made taps work out at $200 each from his original supplier unless he has a batch of at least 20 made.

Being somewhat lazy, I just don't want to try and cut 4 very fine threads.

Dave
The Emerald Isle

 

[DICKEYBIRD]

Could a 1S Lipo battery like this (3.7-4.0v nominal) be dedicated to a bank of 3 plugs in series? (3.9v/3 plugs = 1.3A/plug).

Sorry, just noticed your post. I'm no electrical expert but wouldn't you have to somehow insulate the glow plugs from the cylinders to connect them in series?

Dave you could make a tap from 4140 prehard without heat treatment & I think it would do 4 holes OK in aluminum.

Or strap it in your CNC mill & threadmill it.:hDe:

 

[mu38&Bg#]

James Engines was probably the last source that stocked those taps. Might as well to a couple practice pieces on the lathe for that price. Internal threading isn't that complex. Buy a carbide internal threading bar and it will be fine.

I have many NOS NiCds from being in the RC business years ago. They are definitely getting hard to find now. Even good NiMH are not easy to find. Two plugs connected to a single cell should be fine so you just need a few cells. I wouldn't invest much in the glow circuit unless you plan on running it often.

Greg