Emma Victoria

Hi, hope someone is able to advise me. Its regarding the leading crank pins and coupling rods.

In part 3,page 14, the drawing shows the 3/8" dia crankpin to be 1/4" long. However in part 5,page 159, the drawing shows the front end of the coupling rod to be 5/16" thick.

The bronze bush is pressed in leaving 1/64" proud on the inside and 1/16" short on the outside. So the bronze bush length will be 17/64".. which is 1/64" longer than the pin ? When the washer is screwed on the rod will jamb up tight ??

I have not built a loco before,but this can't be right (can it). I was thinking of making the pin 1/32" longer which will give 1/64" clearance but think that may interfere with the conn rod ?

Is this a drawing error,or am I missing something.

Thanks for reading.

John, I have looked at the drawings and as you say the leading crank Pin has a pin length of a quarter inch. Now looking at the coupling rod which is 5/16" thick, it has a bronze bush inserted and this leaves a step in the 5/16" wide rod hole because the bronze bush is only a 1/4" long.

The retaining washer is made a loose fit in the Coupling rod hole and is screwed onto the crank pin with a C/S screw. This washer is 7/64ths thick and will in fact be below the surface of the coupling rod.

In normal working tolerances the fit is a very slight end float which will stop any binding of pin and rod.

To my eyes it will all work fine.

Regards, Clive

Clive the way I read the drawing is as John did, the bush is 1/16" below the outer surface of the 5/16" rod but ALSO sticks out the back by 1/64" so the pin is too short as the bush is 17/64" long.

I'd add just over 1/64 to the pin so the washer does not quite pinch on the bush when its all done up.

J

Edited By JasonB on 08/02/2013 14:12:47

Thank you both for your input.

Clive, I've sweated over the drawings and deduced that they will bind if made as per drawing. I have made them this morning 1/32" longer to give 1/64" slack. Can allways shave a bit off later if need be. I've got them pressed into the wheels now so fingers crossed.

I hope this will be of assistance to anyone building one in the future.Perhaps the moderator could place this thread in the 'errors' section.

Does anyone know if the designer Mr Wood is still about or if he's on this forum ?

Thanks again,John

I too am building an EMMA. So far I have the wheels, frame, axle boxes and water pump almost finished.

I have a general ?. I have read that in "normal practice" the leading pin, when quartering, is on the RH side. Is the pin on the LH side, above or below the axle centerline? I guess below, because leading would be in "forward " direction of travel. Is this right?

As far as I understand the trailing pin has to be 90* behind in a forward rotation...

Have a look at the Bantam Cock series which is running now. LBSC explains it well. He also says that on a 2 cylinder engine,it doesn't matter which one leads.

Hope this helps. John

Sorry, I missed the protusion of the bush ! getting old and see things that are not there.

Hope it all works out John and good job JasonB has his tech hat on. In fact the bush will be 17/64ths in length.

Sitting here looking sheepish.

Clive

Edited By Clive Hartland on 08/02/2013 17:03:41

I'm the same.Having now gone metric I find fractions very confusing... Thanks Jason for putting that piece of the drawing up.

Clive,

No need to look sheepish - you were honestly endeavouring to help JK.

Dennis

At least John noticed it before he made it ! Did he?

Clive

The author, Henry Wood, is very much alive and well and is a very pleasant and helpful fellow (a Lancastrian, of course, so he would be!) but he is not on the forum.

If you would like to PM or, preferably, email me with the specific problem I can put it to Henry and aks whether he wants to put a correction in the next text.

Diane

Diane, its obvious now from the drawing of the rod/bushing and the pin that there is a 1/64" discepancy in the pin length.

Now its been noted, anyone making Emma Victoria will be wise. Its not a disaster and easily rectified.

Clive

Diane, pleased to hear Henry is doing ok. If he is not a member then I hope he looks in now and again. At least two being built,hopefully more. Its such a cute engine and can ride on the big boys line without costing an arm and a leg.

Will put some photos in my albumn when I get chance.

Thank you. John

John;

Certainly is a cute litte locomotive.

I'm really glad to see smaller locomotives make a comeback again, as they are really practical in many, many ways; about the only problem with them is pulling rakes of riding cars for passenger hauling - not something I'm interested in, but others (fortunately) are.

I hope you do post pictures of your build; keep at it; try to do *something* in your workshop every day, even if it is sorting rubbish or similar!

Another JohnS.

Thanks for the encouragement John. As long as it pull me and my grandson about I'll be happy.

John; My little Tich will pull me and one fully grown daughter.

As long as the grades are not too steep, Tich will do that, so I'd expect Emma Victoria, at 5" gauge rather than Tich's 3-1/2" gauge will be absolutely fine, so long as you are ok with firing.

(coal firing borders on being an art for small locomotives; I think some people just give up and denigrate these small locomotives unfairly)

Another JohnS

I just uploaded some photos of my progress. I am attempting to keep up with the articles!. I know I will get behind, as I am fabricating/making from barstock. No castings will be used. I work as a programmer for a waterjet company, so parts are "easy" to get.

This is what I was going to do about the shortage.

Edited By HobbyNut on 12/02/2013 00:57:04

Ah yes.I also thought of making a stepped washer. You are a little ahead of me.I've also made my wheels out of solid,I'm about to make the counterbalance weights for them and rivet then on. Is that weld I see on yours?

John,I've never fired a loco in my life but I've joined a very friendly society and I'm sure I'll be a fully paid up Driver and Fireman before Emma Victoria gets some coal in her.