Water outlet

Hi all

I need to fit two 14 mm brass bushes to a cold water brass tank. These are to take the outlet fitting and a drain cock. Soldering is not an option as I think the bottom of the tank is soft soldered and trying to heat such a large tank would lead to disaster. Options at the moment are making a tight fit and using lock tight or G B weld. My largest thread tap is 12 mm so to small for this. Any better ideas.

Mike

Threaded pipe with a nut and suitable washers on each side? Does the drain need to drain all of the contents?

How big is this tank? Localised heating is possible with water around a dam?

Thread the bushes and pass the bush through hole in tank and use a 14mm half nut to secure the bush.

How can he thread them, he says he "My largest thread tap is 12 mm so to small for this"

JBWeld should be fine I've seen bushed retained with that tested to 400+psi

You need something like this, designed for the job:
https://www.google.com/search?client=firefox-b-d&q=tank+fittings+brass#imgrc=XrvZ0LLtVbdhMM
Different designs are available.

Tank is 12 inches high by 3 inches round and 1.6 mm thick. I do need to fit bushes about 1 inch from base. No pressure involved so sounds like J. B. Weld is the way to go.

Cheers Mike

If the joint is well away from others and go steady with local heating, a low-melting-point soft solder should be all right. I carried out a similar task not long ago, with a larger fitting with that, without problems.

If the tank wall is thin you won't be able to thread that anyway.. Even ISO-Metric Fine has a pitch of 1.5mm at 14mm diameter.

You need flanged threaded bushes and nuts, with sealant. If it's for cold water any plumbing sealant will work, but will probably need use fibre washers too. The bush and nut alone might not grip a very thin wall..

Is there a special reason for this being 14mm diameter? It does not look like a standard pipe-fittings size and is not a common diameter for metric fasteners.

[Edited because I have just looked back at the thread chart. The ISO-M Fine 14mm threads have 3 pitches, 1mm, 1.25 and 1.5mm, but all are still too coarse for thin plate.]

Edited By Nigel Graham 2 on 10/08/2022 17:45:10

"JB Weld"

FWIW - I purchased the white paste to seal a simple joint. All went well until 24h later I immersed the job in some warm, soapy water to clean prior to painting, Most of the JB Weld fell away.
Adverse comments on Amazon will be read in future !

FF. Depends on what JB Weld product you use.. It's generally taken as granted that the "original formula" is the one to use for strength, heat and fuel proof jobs. This is a dark grey when the white & black components are mixed and is the one packaged in red and black labeld tubes. They do a lot of other products which are OK for specific tasks but should not be confused.

Nigel, most bushes for models have plain OD and are stepped so I suspect 14mm smaller dia and 16mm OD with a standard thread in the central hole. Not sure backnut would be good anyway as its going onto a round tank so will distort the tank and leave gaps, JBWeld would fill the gaps and not damage the tank

Edited By JasonB on 10/08/2022 18:27:37

Link to Ramon's test of some JBWelded joints for those that doubt it's strength. both cold and boiling.

Yes that,s correct. I am using 16 mm brass round bar partly turned down to 14 mm that goes through the tank wall.

This will be threaded M10 to accept my fitting for m10 one end 5/16 x 32 tpi the other. I only use the original J.B.Weld so should be ok.

Mike

Jason

Just looked at that pressure test, put my mind at rest .

Mike

I had to add an outlet to a stainless steel water tank and made my own fitting, similar to the link above by Keith. It just fits in a drilled hole, seals with a rubber washer and held in place with a nut. Much stronger than trying to glue in a fitting.

Paul, how well would that seal on a 3" dia tube?

Make a a rubber washer that has one flat side and the other curved to suit the tube radius. 1 male and the other female on either side of the tube and clamp together with the nut. My tank is 350mm dia and I just used thick rubber and allowed it to squash to fit the curve,

Edited By Paul Lousick on 11/08/2022 08:07:22

Perfectly, if it was fitted to the base.🙂

Think about it. An up-stand within the tank could easily accommodate leaving an inch or so of liquid in the tank. Not exactly ideal as a ‘drain cock. That is posters adding more changes as the thread continues which leads to some of us missing the details added later. Poster will be telling us, next, that this tank must be easily moved or standing on a base of 25mm steel plate.

Unfortunately many don’t fully think through the requirements before posting. And are likely not amenable to altering their initial plans.