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I really like the the old Cox .049 engines.
I still have two old line control airplanes from that era.

I also have an .049 that I found in the mud at a scrap yard one day.
It was seized up, the prop was broken off and the glow head burnt out.
I picked up the parts at a local hobby shop for a total cost of $10
No one was more surprised than me when it started up.
Cox049.jpg

See those reddish speckles on that board that it is mounted on?
Even if you don't really think it will start, it's always a good idea to get
your finger back out of the way when the snap starter spring is released.
:-\

I never thought about using the Cox parts in a build.
Interesting thought!

Rick
 
Speedy,
You can have a lot of fun with the Cox engine parts. I have 4 engines that I made using the piston & cylinder from them. Roger Schroeder had a construction series called the Simple Single that was published in Strictly IC magazine that used the piston, cylinder and glowplug from them. It was quite popular and easy to build. There were a few mistakes in the article, most notable was the wrong thread specification for the glowplug and cylinder to crankcase threads. He called out 44 TPI instead of the correct 40 TPI on the threads. Since the threads did not engage much, if you made the threads loose enough they would work.

E-bay still has lots of parts for Cox engines. Piston-cylinders typically go for about $4 to $5 for the pair if you buy 4 or more. A few years ago I was able to buy complete Cox "Sure Start" engines for about $5 on E-bay so I bought a small stock. Used most of them up, but think I still have 3 or 4.

A V4 would be a little of a challenge to do in 2 stroke because the separation of the crankcase areas to get fuel transfer, but an inline 4 would not be terrible. I have thought about an inline twin to use the Cox cylinders and doing it in the same manner that I am using on the Lobo Twin that I am currently building. But, I have other things that I think I would rather work on for the next project after the Lobo.

Gail in NM
 
There was an article in MEB a while a go on an in-line 4. Go to MEB site and look at the covers in was on the cover

Tony
 
Thanks Tony.
I had forgotten about Jerry James Hex-2 and Hex-4 engines.
tn_hexy.jpg

hex4_1.jpg


And for a bit of inspiration as to what can be done:
http://modelenginenews.org/cardfile/tarantula.html

And finally a couple of mine loosely based on Schroeders Simple Single.
Gail in NM




SimpleSingles.jpg
 
No Problem Gail,
I was looking into a 5 cyl radial I saw "somewhere"

Tony
 
wow lots of responses :D
the little engines sure are cool. my dad has 2 or 3 of them from back in the day.
I know one is a sure start.

what got me going on the idea of using them as a building platform or for inspiration is that they would fit the taig and sherline (eww still need to figure that situation out).

Gail
is the second picture still glow? or is it spark?
looks like a odd glow plug to me.

I want to build a small rc car with a small water cooled jacket.
have tubing that would be about the right size for a cage frame.

is the inline hard to build? the inline 2 hex looks manageable.
then again I say that to allot of things and never even built anything ???
 
Speedy,
Years ago they sold a regular glow plug conversion kit. This way you just replaced the plug and not the whole head.

Tony
 
thank you Tony :D
I did a search after you saying that and found someone selling them.
also thier is a diesel head for them also!! coool.

cox vtwin
[ame]http://www.youtube.com/watch?v=QQx9MouMODc[/ame]
 
I made my own plug conversion by the simple expedient of drilling out an expired glow head,and tapping a 1/4 glow plug thread.Never tried it on an engine though.
I did run two engines on a pusher A-frame type aircraft.They ran in opposing directions to minimize torque roll.You simply started one engine in reverse,using a normal tractor prop!
 
Speedy,
All the engines in the photos that I showed are glow plug. They are all standard Cox glow heads except the right hand engine in the Simple Singles photo. It is a standard 1/4-32 short reach glow plug in a home made head adapter. As Bentprop also said, you can rework a standard Cox head to accept 1/4-32 plugs also.

I also made a compression ignition head for one of mine.

The Hex series engines are supposed to be very easy to build. I have not built one of them so cannot speak with experience on them. The plans for the Hex-2 were in Model Engine Builder magazine issue #9 and the Hex-4 in issue #14. Back issues are available from the publisher. Jerry also sells the plans on his web site:
http://www.jamesengine.com/index.htm
I would go with the back issues of MEB if purchasing them.
Jerry's website has cut away drawings of the engines. Only tricky part in building the is cutting the 17/32-40 threads. Jerry did have taps for that (still may) but they are expensive ($44). Of course that is a problem if you build any engine with the Cox cylinder.

Gail in NM

 
Steve!
those are crazy nice. the radial is WICKED.
is that of your own design?

also, where did you get your tap for the cox cylinder?
possibly are you done with yours? :big: a machinist done with a tool? is that possible.

I have the plans for the hex 2 ;D
talking with James the creator of the hex, Mike Rehmus aswell as Ron Chernich (I am sure you are all familiar with these names)
and the consensus is that I can build it.

what a great bunch of guys, lots of knowledge.
aswel as everone on HMEM :bow:
 
Speedy said:
is that of your own design?

where did you get your tap for the cox cylinder?

and the consensus is that I can build it.



Yes the radial is my design.

I bought the tap from Jerry. It is expensive but very good quality. There is no way I will ever part with it.

If you think you can build the Hex2 then you are probibly right.

I started to build the Hex2 from one of Jerry's castings but ruined it.

Let me know if you decide to build it and i can send you the modifications for the prop hub and other fancy pieces. I also have Jerry's glow drivers pre-made for $30 a pop.



DSCN1530s.JPG
 
hi Steve.
do you have plans for the radial? do you have video of it running?
I am talking with the new owner of COX he is in canada. hopefully I can get everything I need.
I want to build this :D

I contacted Jerry about the tap. he recently sold his last but might have a used one.
 
Speedy said:
hi Steve.
do you have plans for the radial? do you have video of it running?

Yes I have plans for the radial.

I have never even tried to start it. The glow plugs require about 2.2 amps of 1.5 volt power. That would be 20 amps to glow all the plugs. It is a very impractical engine. I did talk to a guy who uses a similar 5 cylinder version on a RC plane.

If you intend to run this thing i have plans for a 5 cylinder version that just might run!! I have not built it so . . . . . .

DSCN0843.JPG


DSCN0878.JPG


untitled.JPG
 
will see about that one after the hex 2.
still waiting to hear about the tap, since my lathe cant do threading.

 
Hello all, this willl be my first post. Im relatively new to machining but not to glow power ,and already have a number of cox engines. I'd very interested in building a hex2 (a pair in fact). If anyone could direct me to a set of blueprints that would be great! Im afraid Jerry James site wont display for me.

Thanks
Ed
 
Welcome to the forum Ed.
There's a Welcome thread where you can tell us a little more about yourself.
I'm sure there are several people who would be interested in your build.
Sorry I can't help with blueprints.
 

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