[modeleng] Re: Valve Gear Modifications
- From: Allen Messer <al_messer@xxxxxxxxx>
- To: modeleng@xxxxxxxxxxxxx
- Date: Mon, 6 Dec 2004 14:01:48 -0800 (PST)
Ian, I'm sort of curious meself! Please let us know
the results.
Al Messer
--- Pendragon <idpriest@xxxxxxxxxxxxxxxx> wrote:
> Barrie,
>
> I am going to test the loco tonight at my mates
> house, I have set the
> valves and timing using the air and tube on
> draincock method and
> conclude that there is a fundamental flaw in the
> design....the eccentric
> rod is I believe too long. I am anticipating that
> the loco will run but
> as you say with irregular beats....will let you know
> how I get
> on......stand by for a full report.
>
> Regards,
>
> Ip
>
>
>
> Priest & Sons Model Engineers
> http://www.kinvermes.pwp.blueyonder.co.uk/p1.htm
>
>
> -----Original Message-----
> From: modeleng-bounce@xxxxxxxxxxxxx
> [mailto:modeleng-bounce@xxxxxxxxxxxxx] On Behalf Of
> BarriePurslow
> Sent: 05 December 2004 23:58
> To: modeleng@xxxxxxxxxxxxx
> Subject: [modeleng] Re: Valve Gear Modifications
>
>
> Ian,
>
> I have seen several of these engines run using the
> original Winson bits
> - O.K. they don't have four square beats but they do
> run. Therefore I
> suggest that your engine has been incorrectly
> assembled somewhere along
> the line. The following runs the risk of teaching
> granny to suck eggs
> but it's the best I can think of:-
>
> I suggest that first of all you check that the
> return cranks are
> correctly set i.e. the big end of the eccentric rod
> is 90 degrees behind
> the crankpin when running forward.
>
> I then suggest that, working on one side of the
> engine at a time, you
> connect rubber tubes to the draincocks and place
> their open ends in
> water. Using the reverser set the radius rod in mid
> gear then rotate the
> wheels until the combination lever and radius rod
> are at right angles.
> The piston valve should now be in the middle of it's
> travel and you can
> check this by applying a few psi of air to the
> engine and observing the
> submerged tubes. A small leakage flow should come
> from each tube.
> Rocking the engine slightly back and forwards equal
> amounts should crack
> the piston valve first one way then the other. If
> this is not the case
> adjust the position of the bobbin on the piston
> valve rod until it is.
>
> The engine should now run. If it doesn't the problem
> is almost certainly
> leakage between the piston valve liners and the
> cylinder bodies.
>
> If you wish to check the dimensions of the relevant
> bits of valve gear I
> can probably scan the relevant parts of the Perrier
> drawings and email
> them to you off list - just ask.
>
> Cheers,
>
> Barrie Purslow
> Warrington UK
>
>
> ----- Original Message -----
> From: "Pendragon" <idpriest@xxxxxxxxxxxxxxxx>
> To: <modeleng@xxxxxxxxxxxxx>
> Sent: Sunday, December 05, 2004 4:17 PM
> Subject: [modeleng] Re: Valve Gear Modifications
>
>
> > Barrie,
> >
> > By any chance re the replacement parts were there
> any changes to the
> > eccentric rod and or the valve bobbin or I suppose
> thinking about it
> > the width of the valves on the bobbin....I fear
> that the eccentric rod
>
> > I have is too long and and the valve bobbin too
> short.
> >
> > My understaning of walsharts is that providing the
> parts are made
> > correctly then the system should work well, and
> that a pooly designed
> > system will not work well and or a pooly made
> correctly designed
> > system will not work. Now then as I regard that
> my workmanship is
> > good and better than most amateur engineers and
> that I have bushed the
>
> > original Winsons bits and bobs out so that there I
> little or no play
> > then the only thing to deduce as to why it will
> not run correctly is
> > that the design was poor to start with.
> >
> > If you can be of any assistance I'd be gratful, I
> am reluctant to
> > remove the liners from the cylinders [I didn't fit
> them] and I believe
>
> > they have been glued in place, this makes
> measuring the internal
> > orifices / distance between ports and port
> dimensions difficult to say
>
> > the least.........if I hade these measurements I
> might be able to
> > redesign to at least make an acceptable running
> engine............ah
> > well might be something to do on Christmas
> morning!!!!!!!!
> >
> > I have never seen the Perrier drawings I take it
> there is considerable
>
> > difference to the Winsons version.
> >
> > Regards,
> >
> > IP
> >
> > Priest & Sons Model Engineers
> > http://www.kinvermes.pwp.blueyonder.co.uk/p1.htm
> >
> >
> > -----Original Message-----
> > From: modeleng-bounce@xxxxxxxxxxxxx
> > [mailto:modeleng-bounce@xxxxxxxxxxxxx] On Behalf
> Of BarriePurslow
> > Sent: 05 December 2004 13:28
> > To: modeleng@xxxxxxxxxxxxx
> > Subject: [modeleng] Re: Valve Gear Modifications
> >
> >
> > Hello Ian,
> >
> > I received the Winson valve gear mods for my Brit.
> I tried them on the
>
> > engine but could not notice any difference. The
> basic problem I had
> > was the abyssmal design of piston valves allowing
> leakage between the
> > bobbins and the liners also leakages between the
> liners and cylinder
> > body.
> >
> > I am at a loss to understand why you need the
> reverser in full reverse
>
> > gear to get it to go forward. Although I do recall
> that the thread on
> > the worm drive was R.H. and I changed it to
> L.H.....but you're not
> > that daft?
> >
> > The best advice I can offer is to build it to the
> Perrier drawings.
> > The Winson Brit was based on these - they
> bastardised, sorry,
> > productionised it!
> >
> > Regards,
> >
> > Barrie Purslow
> > Warrington UK
> >
> >
> > ----- Original Message -----
> > From: "Pendragon" <idpriest@xxxxxxxxxxxxxxxx>
> > To: <modeleng@xxxxxxxxxxxxx>
>
=== message truncated ===
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