Recent Posts

Pages: [1] 2 3 ... 10
1
Restoration of Model Engines / Re: An unknown Twin Marine Oscillator
« Last post by Chipswitheverything on Today at 08:25:33 am »
Well, no doubt at all that this ancient little engine is able to run quite well after all the many years!   Wonder when anyone last saw it spinning?
  The clean up that you got on and did quickly has made quite a transformation to the model's appearance, without , I'd say, removing too much "patination", which was mainly old dirt and some rust!  As the whole construction and design reflects the thinking of an earlier age of model engineering, and has its charm, I think I'd be inclined to just leave the model as you now have it.  Dave
2
Engine Ancillaries / Re: Lucas Mechanical PI System Model
« Last post by Roger B on Today at 07:48:07 am »
Thank you  :)  :wine1:

The gears as supplied have a 3.2mm bore (for 1/8” motor shafts?) so in needed to open them out to 4mm to suit my bearings and oil seals. They were held in a 14mm ER collet with a second gear at the other end of the collet to keep it balanced and concentric. The hole was bored out to ~3.8 mm using a Proxxon 3mm end mill as a boring tool (I made a holder for these when I made the CD carburettor) and then reamed 4mm. In days gone by I would probably just used a 4mm drill but now I am chasing every micron.  The bosses were then parted off. The finish is not very good but the gears will be skimmed again later in the build.

To test the new purchased pump I needed to build a simple test rig to hold a fuel tank, the pump and a support for the pressure gauge. A chance to drill big holes and not worry about the microns, +/- half a mm will do  :)
3
Restoration of Model Engines / Re: An unknown Twin Marine Oscillator
« Last post by Sanjay F on Today at 07:16:00 am »
Quote from: PaulR on Today at 06:47:08 am
Having the flywheel so far away won't help as any tiny error in the shaft will be magnified the further you get from the bearing. Can you move it closer?

Agreed, and I tried to do that, but the shaft has some dints & gouges in it nearer the bearing; when I moved the flywheel closer the wobble becomes amplified   :(
4
Restoration of Model Engines / Re: An unknown Twin Marine Oscillator
« Last post by PaulR on Today at 06:47:08 am »
Having the flywheel so far away won't help as any tiny error in the shaft will be magnified the further you get from the bearing. Can you move it closer?
5
From Kits/Castings / Re: The Bolton -Bertinat -Bailey Triple expansion engine
« Last post by steam guy willy on Today at 02:30:30 am »
Ni "C"  thanks and I first saw one of these from an old Model Engineer magazine...I do have quite a lot including Vol 1 No 1 !!!!!!
The weigh shaft bronze bearings have been  filed  drilled and reamed  7/32nd.....
Cheers
Willy
6
Restoration of Model Engines / Re: An unknown Twin Marine Oscillator
« Last post by Michael S. on June 05, 2026, 09:44:41 pm »
I can't really say for sure why the flywheel is wobbling. However, one possibility would be to drill a larger hole in the flywheel and then fabricate a suitable bushing for the crankshaft thread.
The engine refurbishment turned out well.
7
Your Own Design / Re: Chris's Diesbar Engine Build
« Last post by Sanjay F on June 05, 2026, 09:16:13 pm »
Quote from: Michael S. on June 05, 2026, 07:04:42 pm
Chris, I’m on vacation for two weeks starting today, and I’ve booked a river cruise on the steamer *Diesbar* for June 13th. I hope I’ll be able to take a closer look at the engine. I actually took a trip on that steamer once before, over 25 years ago.

Best regards, Michael  :cheers:

2 weeks vacation, I'm jealous, I could do with that!  :D Enjoy the time off and the trip and I'm sure there'll be some workshop activity too?
8
From Kits/Castings / Re: B.Hick & Son oscillating engine
« Last post by Sanjay F on June 05, 2026, 09:14:35 pm »
Second pedestal completed with its brass bearing and I think I'll move onto the trunnion bearings next ....
9
Machines, Tools and Fixtures / Re: Bending Eccentric Rod
« Last post by Sanjay F on June 05, 2026, 09:11:41 pm »
It's still worked out well, I had to do the same operation for the first time on the flame gulper I made a last year
10
Restoration of Model Engines / Re: An unknown Twin Marine Oscillator
« Last post by Sanjay F on June 05, 2026, 09:01:56 pm »
The engine was stripped cleaned and reassembled. I discovered the trunnion pivots are very sensitive and it took a while to get the correct pressure so the port faces engaged without excessive friction or too loose whereby there wasn't a good seal. I see why they put locking bolts on these now, although I assumed they were oil cups when I first saw them  ::)

So the flywheel, yes it still has a wobble, the reason being is not the actual flywheel itself which has been perfectly machined and runs true. The end of the crankshaft is threaded to a diameter which is not close to the diameter of the flywheel centre, it is also very worn and slightly bent  :(

I could try and fix this by some clever means which I haven't quite worked out or make a new crankshaft or I could just live with it which is sometimes what I feel is needed on these old engines.

I'm quite interested in a solution which does not afford the possibility of further damage as I'm sure I'll come across the same thing at some point in the future:

Anyway, here she is ....................

<a href="https://www.youtube.com/watch?v=1xPptUElFNg" target="_blank">http://www.youtube.com/watch?v=1xPptUElFNg</a>
Pages: [1] 2 3 ... 10
SimplePortal 2.3.5 © 2008-2012, SimplePortal