Anatomy of a normal half inch tap | UK Plumbers Forums | Plumbers Forums

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Forgive my ignorance, with this basic question, but I seem to be struggling to both understand, search for, and source, the appropriate washer, o-ring or gland, for this type of tap.

Maybe, no one ever replaces this type of washer/component?

Background: I discovered a leak in the cupboard from the main stop tap for the house, coming from the shaft seal. It's an old, basic type of tap, 1/2 inch and I simply tightened the gland at the top of the tap, which was not that tight, and it now seems to have stopped. I will of course keep checking. I did note that it did not stop leaking when turned off, which I suppose means the tap is mounted such that the feed side is also on the shaft side? Is this a mistake?

Anyway, wondering what I might have to replace, should the need arise, if the leak persisted, I decided to take a look at a tap I had lying about in the workshop, which was equally old, and had a very similar design. I've replaced the normal on/off washer several times, and have some of those available, but the other one is unclear to me.

On taking it apart, with no little difficulty I might add, because it was so old, I could see some sort of seal for the shaft, at the top of the tap, under the shaft gland, but I could not work out what that was made of. I decided to see if I could flirt it out, or dig it out, not overly worrying if this tap was ruined. I hoped to get it out with some sort of shape remaining, to get an idea of what I was looking for, but it was either from a material that just disintegrates, or, if rubber, or similar, it had lost all its original elasticity, so I was unable to get any idea of its original shape, once I'd eventually got it all out.

From the picture below, can you guys tell me what is it that you buy, to replace the top shaft seal for what is a, more or less, bog standard half inch tap, and what is it called? I ask also, because I have a load of outdoor taps, of similar age and design, and many seem to weep from this area, unless off. Tightening the top gland, so they don't weep whilst on, ends up with it being so tight on the shaft, they become hard to turn on or off. Not much of an issue for taps that remain off, but I have one, for the greenhouse auto watering, that I leave on in the growing season, and that's had to be made very tight to turn, to stop the top weeping.

Basically, what goes underneath the nut you see below, now that I've dug all the old stuff out. Not to worry if I've ruined it, I was more curious, than anything, as a result of the stop tap, and other taps around the house.

Thanks guys.

Tap.jpg
 
I'm not a professional plumber, but this is my take on the stop tap stuffing gland situation!
I think these days traditional style taps start off with an O-ring or nylon gland, but older taps in service seem to get packed with a variety of things depending on what's at hand and the preferences of the repairer! Eg: candle waxed string, wool and silicone grease, vaseline'd string, hemp (which I think is not supposed to be used now), a nylon 'washer', neoprene washer or O-ring of the appropriate size, PTFE string, rolled up PTFE tape, loctite 55 (string), but I gather the old school way was graphite rope.
The finish of the tap spindle in the area where the stuffing gland seals needs a really smooth undamaged surface. The surface generally picks up a dark 'patina' at the seal but if there are any scratches or damage it's worth refinishing it if the repair is to last.
 
Thanks, from those descriptions, my money is on graphite string, from my observation of the material I scraped out. I had no idea that's how the top of an old tap would be sealed, or how I can replace it on either. I was sure there must be just another type of washer, o-ring, shall we call it, that could just be removed and replaced. Getting a suitable replacement material, that would actually work, after some effort by me, seems unlikely. As I mentioned, I'm not too worried about the tap I may now have ruined, it's more about the other taps, in use around the outside of the house, and in particular, the incoming main stop tap, which I was expecting to be able to simply repair, should it prove not to be totally dry now, having tightened that top gland down a little more.

On the bright side, it does seem bone dry now, so it's perhaps moot, but at least I'm now much better informed.

What an odd way of doing it, and thanks again for the info.
 
An old school approach to the packing gland material is to use hemp string coated in jointing paste around the spindle then tighten up the packing gland nut just enough to prevent a leak. A more modern way is to use ptfe tape but personally I use string and have done for 50 years in the trade.
 
Thanks for your additional confirmation that this is how it's done. I still find it odd that some sort of shaped compression washer wasn't used, right from the early days. These methods seem really 'Heath Robinson', but hey, if they work they work, and if they have for your 50 years in the trade, then who can argue. These taps have been around the property for most of your 50 years in the trade, so it's not like any of them are failing prematurely, so to speak, which is quite something.

I have jointing paste, but no hemp string, although I do have a whole heap of ptfe tape, if that's the 'modern' way, so I could try that, just to fix the one I broke, whilst investigating. The main stop tap is not leaking, after a day or so of observation, so I needn't worry about trying to fix that one now. Is there any particular way to go about it? It's extremely thin, seems like you would need an awful lot to build up a tight fit into that top section?

I suppose polish it up, add a little Vaseline on the shaft, to stop it sticking, and then wrap away, for one widths worth, until it's built up nice and thick, then let the gland do its thing, on tightening down?
 
There is a packing gland kit one can buy from a stockist if you want to do a 'professional' repair. It consists of a small tube shape made from a graphite material and it's supposed to fit over the spindle and into the body of the stop tap. It's very brittle and crumbles easily. I generally break some off and put it into the body of the stop tap until there's enough in, tamp it down, then the packing gland nut is screwed down onto it and compressing the material to seal it up.

Now, I've tried this in the past and to be honest I still prefer string and paste because these kits can be a bit hit and miss if you're doing the repair in a tight space under a sink or in a cupboard.

If you're using ptfe then roll it onto a pencil (if in an awkward place) then from the pencil and onto the spindle, loosely but not too loose, until there is sufficient on then push it into place using the packing gland nut. Also you could put some ptfe around the threads of the packing gland nut before you screw it down. You may have to add more if it leaks trial and error style until you get it right. Hope this helps.
 
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The house stop tap certainly would be in an awkward spot. It's hard enough just to get onto the nut to tighten the gland down, but I did manage in the end. With that said, nothing needs to be done there now, seeing as it appears to be sealed. The one I have on the workbench, was more to satisfy my own curiosity, as to how this was/is done, and in order to learn, in case I need to carry out a repair on a tap that's in service, at some point in the future.

For any of those, I would just turn off the water, and remove the tap, and work on it in my workshop. Most are on the outside of the garage, and that can be shut off without affecting the house, so I could work on any such tap at my leisure. Sounds like hemp string is the charm, so I'll get some, seeing as it's not as though I'm in a rush.

I'll check on my jointing paste, to make sure it hasn't gone off, and order some more if necessary, and get some hemp string, so I'm armed for the future, and to repair the tap that's on the workbench.

I suppose replacement taps are probably quite cheap, but that's not the way I do things. Always, if it can be repaired, I will try to do so, whatever it is.

Thanks both for the guidance.
 

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