Tiny I.C. Engine

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I have just finished building the Tiny IC and as yet I have not been able to get it to run. I used aluminium for the head and pressed in stainless steel valve inserts and lapped them to 2mm stem diameter valves. I have the exhaust valve starting to open at 35 degrees before BDC and closed at 5 degrees after TDC, the ignition timing fire at about 5 degrees before TDC but is easily adjustable. As you good people have running engines I would appreciate your comments.
Regards
Errol

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Errol,
Nice looking engines you have made. I too just completed a Tiny and a Powerhouse engine this winter. I am sure you probably verified spark, compression, and fuel draw. My exhaust valve is pretty well closed by tdc but not sure that would make much difference. I did have to adjust my intake valve spring a few times b4 it would run reliably. I am running coleman fuel with a Viton ringed alum. piston. I believe I advanced the timing approx. 20-30 deg btdc and she seems to like that.
Question on the Powerhouse, is that a pmr dynamo? I am thinking to add one to mine.
Good luck and looking forward to your videos.

bob
 
Hi Bob,
Thanks for your kind words and yes it is a PMR Dynamo however instead of using the screws supplied I made 2mm studs and Brass domed nuts to be more authentic. I think this makes the unit look more aesthetically pleasing the only disadvantage is the time taken to make them.
I have made a test jig to test the valve seal on my Tiny IC and have discovered at 150 psi I have a slight leak so I am in the process of making another set of valves and seats. What diameter wire and how many coils did you use for your Tiny IC inlet spring?

Best regards and thanks for the prompt reply

Errol
 
Errol,
Nice work on your engines.

I have built several Tinys and here is what I used for springs.

My intake spring is 8 turns of 0.009 music wire wound on a 0.078 mandrel. Finished OD is 0.115. Free length was set to provide about 0.05 compression with the valve closed.

My exhaust spring is 8 turns of 0.012 music wire wound on 0.078 mandrel. Finished OD 1s about 0.115 also.
I started off with 0.011 wire, same wind, but changed it as I thought I was getting some valve float at high RPM.

Gail in NM
 
This is about all I have at this time. There have been a lot of downloads but I have no idea if anyone is building this engine. If anyone finds errors in the drawings or needs additional information, please feel free to contact me.

I do plan to upload the complete package of notes & prints once they are updated to correct any mistakes or omissions. This will be within the next month.

If you are pleased with post and information provided, a karma would be very much appreciated.

Best of luck & I hope to see some new Tiny I.C. Engines on HMEM.

Arv (putputman)

Hi Arv,

I am impressed by your tiny engine. Just Downloaded plans. Right now building the Nemett-Lynx Engine. After this engine I am tempted to build your engine.
Alas. So little time and so many engines to think of building. My luck with two stroke engines is bad. Two stroke engines look simple to make but very unforgiving. I do OK with 4 stroke.
Thanks for the engine plans.
 
Hi Arv,

I am impressed by your tiny engine. Just Downloaded plans. Right now building the Nemett-Lynx Engine. After this engine I am tempted to build your engine.
Alas. So little time and so many engines to think of building. My luck with two stroke engines is bad. Two stroke engines look simple to make but very unforgiving. I do OK with 4 stroke.
Thanks for the engine plans.

I still have all the discarded Tiny heads for you to use a sinkers Gus, I will bring them to Melbourne for you.

And then you can add your own.

Jim
 
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I still have all the discarded Tiny heads for you to use a sinkers Gus, I will bring them to Melbourne for you.

And then you can add your own.

Jim

Hi Jim,
Please put the sinkers into a small paper box and sign your autograph.
Will use sinkers at the latest extreme spot given by old friend. 8 strikes and all six snagged and only two good size grouper came up.Here is the first fish.

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Gus, thanks for the compliment on Tiny I.C. It was a fun build for me & I still run it now & then.
There have been many people that have built the engine, most of who have added their own modifications and improvements. Each one is sharper than the last. I'll be following your build to see your mods.
Good luck,
Arv
 
Gus, thanks for the compliment on Tiny I.C. It was a fun build for me & I still run it now & then.
There have been many people that have built the engine, most of who have added their own modifications and improvements. Each one is sharper than the last. I'll be following your build to see your mods.
Good luck,
Arv
Hi All,
I am building my putt put at the moment. I have trawled through all the posts (and there are a lot). I have incorporated the ball bearing crank, bushed both ends of the conrod with bronze and used bronze inserts for the valve seats and guides.I have also incorporated the hit and miss mechanism that Gail from NM designed. Gail kindly gave me enough info regarding the disposition of the fulcrum and lever points and I have redrawn all this to suit my own tooling and material availability. They may be of interest to others so I have enclosed them along with images of my trial assembly. The other mod that I did was to use the thick valve stems using the retaining collets but I reduced the diameter of the stem in the port area. I am now ready to do all the final finishing so maybe another month or so will see the project finished.
Cheers,
Kerry from OZ

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View attachment Kerry's Put Put drawings.pdf

View attachment Kerry's Put Put drawings2.pdf
 
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Looks very nice Kerry. I will be watching for the first pops. Your mods all sound good.

I am getting started on a few more "Tiny"s. They are too much fun putting them to work power things.

Gail in NM
 
Good onya Kerry, that's a nice looking engine.

I really must have another go at a Tiny.

Jim
 
Hi together
At the moment I´m building my Tiny and it`s almost at a stage to let it make the first few pops. But i have a question left over. How do you secure the Piston pin and prevent it from making scratches into the cylinder wall? There is no room left inside the piston, cause everything is so "tiny"

Stefan
 
Stefan,
Looking forward to your first "Tiny" pops.

I just make the piston wrist pin about 0.005 inches shorter than the bore and then slightly dome and polish the end of the pin in the lathe. The pin is left to float in the piston.

I use cast iron piston and cylinder and lap them to fit with no ring. The pin is 1095 steel.

I have one Tiny with many hours on it and no visible scratches in the mirror lapped finish of the bore.

Gail in NM
 
Hi Gail

Well i`m glad to hear that leaving the pin floating in the piston is no Problem here. If it works for you, it`s goin`to work for me too. :) In other engines i used to hold the pin in place with a little M1.6 or M2 screw depending on the size of the piston.
Because i converted the Plans from putputman from imperial to metric i just found out that my connecting rod is too short.:eek: My mistake! So i have to make a new one. I´ll keep you updatet...

Stefan
 
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