curious about cox engines

pkrankow wrote:The socket is drilled with a collar, the collar is then swaged onto the ball of the connecting rod. It isn't a one piece affair, and it really isn't super high tech in the design.

The materials however, that was cutting edge for the time and is still pretty darn good stuff now!

Phil

what exactly does that mean? the collar is then swaged onto the ball?

Here is a cut-through (by "altidsulten") that shows the attachment;

Surfer_kris wrote:Here is a cut-through (by "altidsulten") that shows the attachment;

wow thanks, that actually explains alot. some time last sommer i thought it would be cool if i could make one of these nitro engines from a few pieces of aluminum but i dont have a lathe, so i have been just using a drill and my hands. i made a few piston and sleeve sets but they werent quite right. i couldnt ever figure out how to make the piston pin but maby i can make that ball joint. i was trying to make a tiny replica of my traxxas 3.3 engine but cox might be easier to make.

Without the proper equipment and the knowledge to use it you'll pretty much SOL.

alass we all have dreams

i to dream of a 049 twin...an then a opposed 4 cly cox to run in my lil cub j 3

<<( drifts off to wonder land).....

I think it can be done. My brother made a crude operating steam engine without a lathe when he was 14.

If you research making small engines with the correct tools, inspiration may strike for making them lacking the most important of the tools (the lathe). Steam and air engines are a common machinist student advanced project. There is a lot of information available if you look for it.

So called "popcorn engines" are just awesome!

Phil

SuperDave wrote:Without the proper equipment and the knowledge to use it you'll pretty much SOL.

i know how to use a lathe and all that equipment, and i think im a pretty good welder i just dont have $400 for one and i tried making a tiny oscilating steam engine and its mostly done except i need more metal for the connecting rod.

As many times as I have seen that photo, I never noticed the funnel shape of the venturi.

This begs the question: When we enlarge the inlet of the back plate and then the inlet of the Tank venturi should we have a conical reamer to slightly increase the diameter and volume of the entire manifold and not just the inlet

I see a set of tapered Diamond reamers in my kit from MicroMark

http://www.micromark.com/diamond-reamers-set-of-10,9378.html

ekitten2 wrote:alass we all have dreams

i to dream of a 049 twin...an then a opposed 4 cly cox to run in my lil cub j 3

<<( drifts off to wonder land).....

I dream of being called Loretta and having babies.

ooooooopps wrong forum

fredvon4 wrote:As many times as I have seen that photo, I never noticed the funnel shape of the venturi.

This begs the question: When we enlarge the inlet of the back plate and then the inlet of the Tank venturi should we have a conical reamer to slightly increase the diameter and volume of the entire manifold and not just the inlet

You'd have to be very careful to not chinger up the crank end throat where the reed seat is. Bad reed seat and all work opening up intake goes down the porcelain. Probably enough to just smooth the transition where the intake is enlarged.

<< giggel snorts at Goddard...im a memb or that forum as well

fredvon4 wrote:As many times as I have seen that photo, I never noticed the funnel shape of the venturi.

This begs the question: When we enlarge the inlet of the back plate and then the inlet of the Tank venturi should we have a conical reamer to slightly increase the diameter and volume of the entire manifold and not just the inlet

I see a set of tapered Diamond reamers in my kit from MicroMark

http://www.micromark.com/diamond-reamers-set-of-10,9378.html

If you went much bigger there wouldn't be enough vacuum to draw fuel. Just opening the small end of the venturi can make it fall on its face. Some people have opened the outlet behind the reed, but like Ahrma said, don't foul the reed seat.
That engine in the picture is not a reed valve engine, by the way, it has a rear rotary valve.

I never noticed the rotor........

Anyway so when doing the .082 mouse mod you do not drill all the way through? I must have read it wrong.

Ron

"I dream of being called Loretta and having babies." - Johnny Boy

Visualize the image of JB in "drag" and on prowl for a mate.

cribbs74 wrote:...so when doing the .082 mouse mod you do not drill all the way through? I must have read it wrong.

Ron

Just turn the .082" bit through the venturi tube opening, that's all. You're only drilling air past that.

RknRusty wrote:That engine in the picture is not a reed valve engine, by the way, it has a rear rotary valve.

WHAT???? Are RR1's so common in Denmark they can afford to chop them in half???

(Think the 'rotor' is the reed clip...)

Tis not an RR1 but has a rear disc.

Yeah, thats a reed circlip on a plain Babe Bee...

14TYLBOW

Two things:

I lived in Anoka MN briefly for sixth and seventh grades at springlake park while my dad commanded Twin Cities Army Ammunition plant in the sixties.....small world

In one of your posts you said something like making one of "these nitro engines"

Some of us old pharts always cringe whenever these engines are referred to as "NITRO" engines. It is true that some internal combustion 2 stroke engines do benefit from nitro methane added to the "glow" fuel....most will run just fine without ANY NITRO. In this case the fuel is primarily Methanol (one of the alcohols) and the ignition is sustained by a catalytic reaction of this alcohol with platinum in the "glow" plug.

Gasoline engines usually use a 10,000 to 60,000 volt spark jumped across and air gap in a "spark plug".

You are welcome to use the terms you learned and seem to be prevalent in the hobby

....I am just letting you know that this "NITRO" term, is really a marketing bunch of stuff started by the RC car guys to make it sound like all of them had some 3500 HP fire breather under the hood....grin

yep, i think you're right on that gas car thing, we always called 'em 'gas powered' models, even though there was no gas in the fuel, probably a carry over from the 'olden days' but it was always 'glo fuel'