cylinder oiling drillings and Tangye mods

[Tony MartyrParticipant @tonymartyr14488]

[Tony MartyrParticipant @tonymartyr14488]

I have just finished my first build and run on air and steam of a Double Tangye engine.

I have now stripped it in order to make some modifications and cure some leaks.

The drawing shows a undimensioned tapping on the top centre-line of each cylinder labled "tap for oiler".

What sort of 'oiler' would function against full steam pressure? Would that be an oil cup with a screw-cap for use before and after running?

The two modifications will be to improve the function, probably at the expense of form and style.
1. The valve excentrics can only be adjusted by removing the sheaves which is more than a little inconvenient – redesign required.
2. The governors looks pretty but doesn't work well so both the inlet valve and the governors drive need replacing to include ball bearings.

Rather amazed that a design would put 4 close coupled bearings in line on a rigid shaft – my apprentice test piece was scraping 3 in line and that was bad enough – these are worse because the caps of two of them are at 45 degrees making disassembly unnecessarily difficult. A bit of a challenge!

[JasonBModerator @jasonb]

It would be an oiler with a lid that can be screwed on so no loss of pressure and a cock type valve below to open it, the valve can be used to adjust oil flow or you can make one with a needle valve. On a small engine like this unless you are going to be running for a long time a dummy oiler can be used as a "plug" that can be removed to allow a drop of oil to be added at the start of a run before being screwed back in place.

Easiest fix for the eccentrics is to drill a small hole in the strap so you can poke an Allen key through to get to the grubscrew, do it through the

[Rik ShawParticipant @rikshaw]

Hello Tony – I am part way through the DT build. I will probably ignore EW's requirement for cylinder oilers and have either a displacement or mechanical lubricator on the steam input. Will have to look carefully at the unstarted valve eccentrics – the same with the governors or do as Jo does on another forum and replace them with a Pickering.

I agree with you on the convoluted crankshaft design setup, I think EW was an engineering sado masochist. I bet he cackled insanely as he draughted up THAT nightmare.

Rik

[JasonBModerator @jasonb]

I knew I had the photos, top shows a similar one to what I describe above and the lower being fed from a mechanical lubricator.

We have had similar discussions about the Clarkson twin/compound and it's 4 bearings on here before, I have redesigned that to reduce the distance between the two "halves of the engine and therefore shorten the crankshaft and up the size of the outer bearings but probably more than you want to do at this stage.

[norman royds 2Participant @normanroyds2]

wanted helping to find drawings for 3 inch RANSOMES COMPOUND 6.N.H.P.TRACTION ENGINE thankyou for any help i will pay any cost incurred

[Tony MartyrParticipant @tonymartyr14488]

Thanks Jason – I do like the photos. I would like to know how the cross-head slides within the main frame were set up for machining, perhaps on a horizontal borer but its a horribly 'bouncy' intermittant cut demanding a very ridgid set-up..

As for the hole in the excentric sheave as the answer to the adjustment of the valve timing – of course!
Why of earth didn't I see that as the answer – I'm trying to think of an excuse other than senility.

Thanks for your help

Rik: I don't know how far you've got but to get the 4 bearing alignment sorted out in the horizontal plane I machined the two inner bearing pedestals and then made a plain shaft jig to check the height of the two frames having already machined the bearing seatings – it meant having to take the castings out of the milling machine a couple of times but resetting with a precision level worked OK.

Tony

[JasonBModerator @jasonb]

Tony the only downside to the hole is it can disturb the oil film but unlikely to be an issue on a model unless it is going to be put to work.

Not sure about the machining but some form of shaper with a tool that could slowly be rotated may have been another option with a guide in the piston rod hole

The photos came from here, you can right click and copy the image URL to view but they don't seem to be showing up on the page for me. Lots of other interesting old engines on that site, this page is a good start.

Norman I can't think of a published design for a 3" but you could double up Hughes's 1.5" drawing but that is still only a GA. Available from Blackgates or Sarik drawing No TE10

[JasonBModerator @jasonb]

Coming back to the 4 bearing arrangement I just looked at 4278 which had part of David Piddingtons series on Tangye products and there are several twin or compound engines there and from what I can make out all are just the two bearings at the ends of the main frame.

Like the Clarkson I wonder if it was originally designed as a single and then cobbled together as the twin or Bertinat's compound. Anyone fancy a conversion?

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