Sticking Engine M2

[hammer]

 I do have a problem, can't run it in using the lathe or drill.    Geoff

[zeeprogrammer]

Thanks for the pic and explanation. I'm not that familiar with wobblers but now I remember there's usually something holding the cylinder against the port.

I do have a problem, can't run it in using the lathe or drill.

Do you need to? It was running on air earlier. Just keep running it?

[Bearcar1]

Looks like you will need to make up a quick, down and dirty fixture to hold a small pinion gear to mesh up to that driven gear between the cylinders Geoff. That is if you still want/need to break the engine in using external power. Neat looking little beastie.


BC1
Jim

[hammer]

Yes I need to run, bed or break it in as it needs 40psi to run at the momment. Top pressure in the boat will be 25psi. So about 5lb on air with no load is the aim. The boss won't like me running the compressor for an hour or more, it makes so much noise I would end up  crazey. A gear shaft I think the best option. Geoff  Photo of Mk1 in boat

[arnoldb]

Good going Geoff.

  I thought the port holes would require a bit of opening up... 

Going back to the photo where you show the engine's spring mechanism, that looks to be a fairly substantial spring.  Woblers are very sensitive to their spring settings - too much pressure from the spring will cause them to run very stiffly, requiring high pressure.
Could you perhaps try and find a spring made of thinner wire and add a couple more windings on it ? - that should give you a pretty significant reduction on the pressure needed to drive the engine, unless you have a lot of friction left on the crank shaft bearings, crank pins, connecting rod packing glands and piston fit.  In theory, the spring pressure applied to the cylinders to keep them on the port faces should be just enough to prevent the steam/air pressure from blowing them off the port faces.

I'm not too keen on running in engines by external means; the reverse driving through the drive train wears in the different joints and bearings on opposite sides of where wear would occur during the engine's normal operation - but that is just my own view and not necessarily correct.

Kind regards, Arnold

[hammer]

Thank you Arnold, I know you know what your are taking about. Good advice again. Yes it is sensative to the possition of the nuts. By the way those springs have been streched, in an atempt to make them softer. But I will have another look in the spring box. Geoff

[Don1966]

Looking good Geoff, now I can understand what you are doing with the wobbler. Nice looking paddle boat too. Still following along here with interest.

Don

[hammer]

Thank you Don, always good to know others are interested. As I said at the start a low centre of gravity is most important in a model paddler, especially if using steam the boiler having a high c of g.
Arnold, the pressure on the cylinder clamp is adjustable by screwing in or out the nuts. But with the stiff springs in is hard to fined the sweet spot. The friction is mainly from the conrod glands. Geoff

[hammer]

 I have done the running in. Funny how some engines run better one way, lucky for me it is the right way. Here is a better video and a better run.
<a href="https://www.youtube.com/watch?v=7PsbzyY5hjQ" target="_blank">http://www.youtube.com/watch?v=7PsbzyY5hjQ</a>

[Bezalel]

Looking good Geoff


 


Thanks for the Videos - its always good to see another goer


Bez

[Don1966]

I like that video better, looks like you have found all of your problems, nice runner too. Thanks for the video.

Don

[steamer]

Well done Hammer!

Dave

[hammer]

I know this is an engine site but I will show the boiler made for the paddler. In an attempt to keep the CofG low and still retain capasity. No1 ready for soldering. No2 Burners as finished. No3 The control end with regulator on gas & seperator on exaust. No4 Fill pipe & blow down pipe (goes over board) No5 The trap door is there to make sure the flame dosen't burn in the manifold. Geoff