Captive Valve Spindles

[gwrfan]

Gentlemen,

I'm just about to make some boiler fittings, and I can't find a sketch of captive valve spindles anywhere. There was one shown in the Southern Fed Newsletter 3 or 4 years ago.

Anyone got a picture/sketch they could post here?

thanks in advance.

Geoff

[stantheman]

Same article/drawing appears on Southern Federation web site under the section 'Notices' highlited at bottom of this block. See www.southernfed.co.uk/notices.htm

[gwrfan]

Hi All,

I have that sketch, but what I'm after is the sketch that shows a complete valve to the new requirements, not an alteration to existing spindle.

Thanks for your help so far.

Geoff

[houstonceng]

Try this one, sent to me by a fellow club member.

Attachments:

[gwrfan]

Thanks Andy,

That looks like the detail I was after

Geoff

[maunsell]

I have to say that I am not impressed by the sketch showing a modified a valve spindle machined down and threaded to take the handwheel which is then held in place by a locknut. For me this is just a "bodge job" offering almost no security against the handwheel unscrewing off its spindle, possibly with the valve open. My practice has long been to fit the handwheel on a 1/8" square with a 10BA nut to secure the handwheel in place.
While this is very practicable in 1 1/16" scale and above, I question the practicalities, desirability, or risk factor in say 3/4" or 1/2" scale.

[houstonceng]

Since the handwheel and spindle are both have RH Threads, attempting to close the valve would tighten the knob onto the spindle. There is, therefore, no need to fear the handwheel unscrewing with the valve open.

Nevertheless, I prefer to see a prper square end on the spindle and a suitable square hole inthe knob, the latter held on by a domed nut.

[maunsell]

Regretfully I have seen handwheels unscrew from the spindle, particularly when drivers use a little device with two prongs to engage in the handwheel spokes/holes or even a fine nose pair of pliers to open a valve that is tight!