Bibcock for 11/2″ Allchin traction engine.

[Bryan CedarParticipant @bryancedar96259]

I have an 11/2″ Alllchin tracton engine that is missing its second tiny bibcock on the water tank.The photo attached, is on 1 centemeter graph paper. These cocks do not appear on the Allchin drawings, in fact neither do the cylinder drain cocks.

Can any forum member please tell me whether these cocks or the castings are available off the shelf.

[Bryan CedarParticipant @bryancedar96259]

Source of Allchin bibcocks.

[JasonBModerator @jasonb]

Seem to remember someone asking before and we drew a blank, looks like its a case of make it yourself. Was it a 5BA thread from memory?

 

J

[Bryan CedarParticipant @bryancedar96259]

Hi Jason

 

Thanks for your input. The cylinder drain cocks are 5BA and the thread for the bibcocks are 5/32″. The vacant tapped hole is strangely 5BA and the existing bibcock is 5/32″

 

It is odd indeed that neither the above cocks show on the drawings, so I wondered if at some time they were available off the shelf.

 

Regards

 

Bryan

[JasonBModerator @jasonb]

5/32 drain cocks are readily available, are there any signs that the spout was silver soldered onto a standard cylinder cock?

 

J

[Bryan CedarParticipant @bryancedar96259]

Hi Jason

 

No the cock body is one piece. Where are the 5/32″ cocks available?

 

Bryan

[JasonBModerator @jasonb]

Reeves, Stuarts, Polly (Bruce engineering) etc

 

J

[Bernard Laycock 1Participant @bernardlaycock1]

I’ve been following this post with interest as I am building the Allchin and have been looking for a bibcock for quite a while. Incidentally, Bryan gives me the impression that his engine has two bibcocks, whereas mine only has one. Is the one in the photo the one already on your engine Bryan? If I’m right, that’s all you need, if not, I’d like to know where the other one is.

 

I’ve followed up JasonB’s suggestion re suppliers and eventually several others, absolutely without success and I thought it would be good idea to list them to save anyone else wasting their time. They are: Reeves, Stuart Models, Polly (Bruce Engineering), MJ Engineering, Blackgates, EKP Supplies (They actually had a range of three in their 2010 catalogue, but the smallest, 1/4″ x 40 was too big for us, but even those have now disappeared), CES and Live Steam Models.

 

It seems that I will be contemplating making my own and it would be lovely if any builder who has undertaken this task and would be willing to reveal how it was done.

 

Bernard

[JasonBModerator @jasonb]

Bernard, I’m sure the making of the straight cylinder drain cocks has been covered many times over the years both in ME and various books.

 

You would make the bibcocks just the same but from a longer bit of metal so the spout can be formed and then bent. The spindle is cut to a shallow taper and while the topslide is set a matching reamer is made to finish the hole in the body.

 

These are the cylinder drains on my 2″ Fowler, although the body is a bit larger than yours the thread at each end is 5BA

 

J

[Bernard Laycock 1Participant @bernardlaycock1]

Thanks for the info, Jason. I have a supplementary question based on looking through the 29 photos accompanying your post and the particular one that raised my interest was that of the Allchin handwheel. I have been scratching my head for a very long time trying to come up with a way of making it. I’m not quite sure in what context you showed the drawing (There doesn’t seem to be any text associated with it). I’m just hoping you might be able to clarify the details as to how it might be made?

 

Bernard

[JasonBModerator @jasonb]

There was somewone else asking about making them, I’ll see if I can find the post but the search function on this forum is pants.

 

J

[JasonBModerator @jasonb]

Bernard, it was you who was asking back in february and thats why I added the photo, two of us suggested turning the wheel with a flat ring on the outside and then mill/file most of it away to leave the 4 tabs.

 

This is the post

 

J

[Bryan CedarParticipant @bryancedar96259]

Posted by Bernard Laycock 1 on 25/01/2012 16:18:31:

I’ve been following this post with interest as I am building the Allchin and have been looking for a bibcock for quite a while. Incidentally, Bryan gives me the impression that his engine has two bibcocks, whereas mine only has one. Is the one in the photo the one already on your engine Bryan? If I’m right, that’s all you need, if not, I’d like to know where the other one is.

 

I’ve followed up JasonB’s suggestion re suppliers and eventually several others, absolutely without success and I thought it would be good idea to list them to save anyone else wasting their time. They are: Reeves, Stuart Models, Polly (Bruce Engineering), MJ Engineering, Blackgates, EKP Supplies (They actually had a range of three in their 2010 catalogue, but the smallest, 1/4″ x 40 was too big for us, but even those have now disappeared), CES and Live Steam Models.

 

It seems that I will be contemplating making my own and it would be lovely if any builder who has undertaken this task and would be willing to reveal how it was done.

 

Bernard

REPLY :-

 

Hi Bernard

 

Yes the bibcock in the photo is from my Allchin and does require two as shown. The missing one should be level with the bottom of the water fillicng pocket, at the forward end. The drawings show 5/32″ tapped holes to receive them. For some unaccountable reason my Allchin has the vacant hole tapped 5 BA which is a little smaller.

I am unable to make such a small component, but I know a man who can !. Perhaps he would be prepared to make a batch as I know he sometimes makes components for sale on Ebay. This is a very fiddly component, being so small. Needless to say I did not make my Allchin but bought it 99.99% complete.

Bryan

[Bernard Laycock 1Participant @bernardlaycock1]

Hi Bryan,

 

The bibcock on the side of the tender is the one I know about, but I can’t locate the other one. Can you help me find it?

Also I’m becoming reconciled to having to make my own, but will defer this decison until I know whether your ‘man who can’ could be persuaded to. If this fails and I have to fall back on my own resources, I’ll keep it in mind to make one for you if we stay in touch or I have a way of contacting you.

 

Bernard

[Bryan CedarParticipant @bryancedar96259]

Posted by Bernard Laycock 1 on 27/01/2012 16:50:53:

Hi Bryan,

 

The bibcock on the side of the tender is the one I know about, but I can’t locate the other one. Can you help me find it?

Also I’m becoming reconciled to having to make my own, but will defer this decison until I know whether your ‘man who can’ could be persuaded to. If this fails and I have to fall back on my own resources, I’ll keep it in mind to make one for you if we stay in touch or I have a way of contacting you.

 

Bernard

Hi Bernard

 

I guess that you have the book Building the Allchin. The 1979 issue shows the two bibcocks on page 25, one on the inspection plate and one to the forward end of the water filler.

Your offer is very kind and we will keep in touch.

I have sent a resin casting to my friend to look at to see if he can make one of these bibcocks. Both tappings are shown on the drawings as 5/32″

The archives on Station Road Steam for 11/2″ Allchins show some models with these bibcock and some without also some with just one. I guess many people could not bother to make these fiddly things, or at some time they were available off the shelf.

 

Bryan

Bryan

[Stewart HartParticipant @stewarthart90345]

Her’s one I’ve made

 

Stew

[Bernard Laycock 1Participant @bernardlaycock1]

And what a lovely job!

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