Stuart 6 A lubrication and Stephenson lever

[Midship]

Hello,

I need some help to modify the lubrication of my 6A, my concern is the lubrication of the connecting rod crankshaft side, I will make a lubricator with small pumps, like this one





and I am looking for pictures of a similar installation on this engine with the lubrication of the head of connecting rods


The other point is to modify the lever of the Stephenson slide to get an handle on that kind



At that time it like this



thank for your help

Kind regards

[mcandrew1894]

Hi Midship,

I used a model locomotive ratchet style dual pump to feed the connecting rod "big ends". Though my engine is not a 6A, it is a compound.

The connection is via flexible teflon tubing. One end is fixed at the base of the rear standard to which I have hard plumbed the pumps. The other end is a fitting bolted to the side of the connection rod a the cross head. There is a "U" shaped loop of tubing in between these two points that flexes as the cross goes up and down.

From the cross head I have rigid tubing affixed to the connecting rod down to the big end brass.

1 click per revolution is more than enough to lubricate the rods in a very positive way at 600 rpm.

Thanks to Steamboat Jack for the inspiration!

Dave

[steamboatjack]

The details of parts for these systems are available from www.interlubesystems.co.uk they have many suppliers.

For engines of this size the best route is to use a tank with two pumping units, one for cylinder oil and one to supply all the bearings via manifolds and single line metering flow units, neither are cheap but the system is very good.

make your own tank, use roller clutch units instead of rachets (you need two) the pump units are available as spares for the AX range of industrial greasing units (work fine with oil) I would suggest an orange unit (0.025cc per stroke for bearings and a red (0.010c for cylinder) speed of the unit can be gauged in service and adjusted by the length of the connection lever.

On the manifold fit a single line metering unit for each bearing, there are various flow rates for these each proportional to the others. Use 4mm flexible tube to the bearings or copper for main bearings etc.

Downloads for these items are available at interlube, look in products,industrial, oil metering valves for the flow units and
products,industrial, AX range for the pump units.

email me if you need any help, with a common tank you use cylinder oil for both systems, grade 460 would be best.
regards Jack

[Midship]

Hello

Thanks to you two, I have bought yet the pumps they are from Interlube, green, do you have some pictures of your realisations?
I don't know if it is necessary to get a different oil or not for the cylinder lubrication, as I am condensing

best regards

[mcandrew1894]

I know Jack has published pictures before... I'll take some pictures of mine this weekend.

Dave

[Midship]

many thanks

any idea about my other problem, the design of the Stephenson lever

have a nice WE

Thierry

PS: We have our annual association meeting this WE, some pictures on the blog monday

[steamboatjack]

The photos show (hopefully) a system I fitted to a friends engine some time ago, rather than build a tank this is a new tank from a model engineer dealer modified to suit, the pumps have screw connections to the pipes but the new type are push fit, other wise the same. The two brass diameters either end of the pump shaft contain the roller clutches but they would be better situated inside the tank as the shafts do tend to wear in way of the rollers.
Regarding the oil, if you are condensing then a straight oil (non compounded) is best, compounded oil is difficult to separate from the condensate. It is important to get NO oil in a boiler despite what some otherwise quite sensible steamboaters may state. I find non compound 460 cylinder oil ideal for the pressures you will use, in fact the "straight" cylinder oil is the same stuff as "straight" bearing oil, just a higher viscosity.

Regarding the stephenson valve gear, I have spend many hours on this subject as I am afraid to say most engine designs are just "plain wrong" I am not sure about the 6A as I only have a G.A. drawing, If you e-mail me I would be happy to have a look.
Regards
Jack

[Midship]

Many thanks Jack

Wonderfull realisation, do you have some pictures of the connecting rod détails?

I will send you details of the Stephenson lever soon

nice WE

Thierry

[Midship]

Hello, I am still looking for some details and picture of the lubrification of the bearing of the connecting rod on the crankshaft, I plan to use a flexible pipe, but where do I have to connect it and how

many thanks for your ideas



kind regards

Midship

[steamboatjack]

If you refer to my pictures above, the middle picture shows the left hand connecting rod set up with two flexible tubes, the upper one feeds the crosshead bearing the lower one just below feeds into the connecting rod direct, the rod is drilled through its length and hence to the bearing, Its best to drill from both ends then the upper end can be tapped to take a blanking screw.
By having the flexible connection as near as possible to the crosshead you limit the lateral movement and so hopefully extend the life of the pipes, I have had the same setup on Grayling for twelve years without problems.

Regards
Jack