Attempting Gordon Nano

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Despite still being a non-runner, I decided to anodise the cylinder and spinner anyway.
Its surprising just how small this engine is when compared to the Clanford Clan.
 

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Despite still being a non-runner, I decided to anodise the cylinder and spinner anyway.
Its surprising just how small this engine is when compared to the Clanford Clan.
what a lovely deep red. nothing wrong with a plain aluminium finish - but the colour certainly lifts it. does it get stored in an oily rag, or on a purpose made mounting?
 
If you make the Nano carb exactly to the drawings, the carb bore of 2.4mm diameter has an area of 4.524 sq mm. But the 2.2mm dia jet projects into the bore some 0.4mm beyond the centre and this reduces the choke area to 1.356 sq mm. [This neglects the reduction in area caused by the needle itsself]. If the jet does not project this much into the carb bore, the choke area will be far too big to allow the engine to draw fuel. By contrast your Clanford Clan has a carb area, [neglecting the reduction caused by the needle], of 1.53mm for an engine almost 2.5 times the displacement. Even if built to drawing, unless the Nano is capable of much higher rpm than the Clan, the carb area is much too large.
Ken
 
If you make the Nano carb exactly to the drawings, the carb bore of 2.4mm diameter has an area of 4.524 sq mm. But the 2.2mm dia jet projects into the bore some 0.4mm beyond the centre and this reduces the choke area to 1.356 sq mm. [This neglects the reduction in area caused by the needle itsself]. If the jet does not project this much into the carb bore, the choke area will be far too big to allow the engine to draw fuel. By contrast your Clanford Clan has a carb area, [neglecting the reduction caused by the needle], of 1.53mm for an engine almost 2.5 times the displacement. Even if built to drawing, unless the Nano is capable of much higher rpm than the Clan, the carb area is much too large.
Ken
Hi again Ken,
Thanks for the info.
With the revised spraybar which passes through the venturi I have 0.9 sq mm area so much better than the standard setup.
The engine draws fuel readily when choking the carb and I am still looking to find better fuel.
I have put this model aside awhile and am going to build a simplified rig to test out various combinations for very small capacity designs.
Re-making parts with turned threads is so time consuming and frustrating when the result doesn't work so I plan to make a simpler version with the cylinder clamped via the head with three screws and the case cover in a similar fashion. The crankcase and head will be pretty much simple blocks as weight is not an issue and for short run trials heat dissipation can be managed.
This will also allow me to explore reed valve and rear rotary intakes too.
I guess I am a bu**er for punishment.
Rich
 
Please need the complete project!
I didn't get it on Nexus!
 
Been a while since I visited. Just want to say don't give up yet. I've made 7 of these now and most of them have been a real chore to find the running settings and get them started. I actually put 3 of them aside because I got so fed up with not getting any response at all. Pulled them out a month later and got them all started and running. Don't know what the difference was.
Yesterday I made some spring starters for them as per the Nano drawings. What a difference - they are now so easy to start - it's a real joy instead of a depressing chore. Also makes it a lot quicker and easier to find the correct comp and mixture settings.
Quick video here:

Fuel is just equal parts ether, kero and castor.
Well worth giving the spring a try, I think it's the speed that it turns the engine over that does it.
Dave
 
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Been a while since I visited. Just want to say don't give up yet. I've made 7 of these now and most of them have been a real chore to find the running settings and get them started. I actually put 3 of them aside because I got so fed up with not getting any response at all. Pulled them out a month later and got them all started and running. Don't know what the difference was.
Yesterday I made some spring starters for them as per the Nano drawings. What a difference - they are now so easy to start - it's a real

Hi Dave
You made 7???!!!! Wow!
I must say the video shows a sweet motor! Well done!
I am also encouraged by the fact you are using equal mix of fuel too.
After a break since my last post I did make yet another piston and refined the fit but still no luck even using my'safe' electric starter.
I will revisit it but it is doing my head in. Not sure if its my build quality or what but hey ho.
Thanks for posting
Rich
 
Its funny how often a project ends up being more than just making the parts. Its all the things you have to make to achieve it!
So, I made my cutter, 4 blade as opposed to the authors 3 blade, from En24T and hardened and tempered it. It would be nice if it was a 2o tooth or so but there are limits to my abilities!!
Also I realised I would need to make some fixtures to hold the cylinder for the machining as I wasn't intending in following the author method of milling in the lathe.
So, a threaded bush to hold the cylinder in a rotary table and an angle jig for the drilling of the transfer ports.

You could show how you used this jig on the rotary table.
 
Today I drilled the transfer ports using a jig at 45 deg. I confess I eyeballed the position although the offset distance was dialled in using a pointer from the datum edge.
Next is lapping which I normally do with a short split lap but I didn't have a suitable one this small so decided to make a different design.
Basically, two cylindrical rods milled to half diameter, soft soldered back and turned to the finished diameter for the job.
Centres and ferrules also made for keeping it together when separated by de-soldering and cleaning off the solder from the faces.
In use, one end is held in the chuck and the other in a dead centre, the ferrules keeping it together.
Paper shims are added to increase the diameter and being a long lap gives better control of diameter. Or the theory says!
What you have made is commercially available and is known as a " needle eye" lap and in the real world they are the usual way to lap small bores. The halves are normally just forced apart with special pliers.
Ken
 
What you have made is commercially available and is known as a " needle eye" lap and in the real world they are the usual way to lap small bores. The halves are normally just forced apart with special pliers.
Ken
Thanks Ken,
I have learnt something new.
Rich
 
"I am gobsmacked by the quality and intricacy of design produced by such a young enthusiast at the time."

I meet him and enjoyed a 3-hour car trip on business (he worked for Ricardo's by then and had setup their Tokyo office) the guy is plain clever !!
 

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