Sizing through hull fittings

Sailfree

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So that I can order them in advance with boat in the water.

I assume the dia is the internal diameter of the pipe?? I assume I will have to make allowance for thickness and measure o/s diam.

Anyone know of any tables that give both i/s and o/s dims of these fittings please?
 
The BSP sizes were originally the inner diameter of the Victorian malleable-iron gas pipe on which the thread would be cut in situ - on the outside. So the inside of modern fittings will be similar to the size number, but not the same because their wall thickness is different to 150 year old gas pipe.

Officially, the standard is now metric with a defined set of dimensions in mm, and the size is simply an identity number rather than a dimension in any unit.

Pete
 
Can I be clear about the fittings

Looking at the ASAP website they have Bronze through hull skin fittings and I connect these to a DZR stopcock?

Bronze threaded skin fitting

Threaded-Skin-Fittings-ASAP-Supplies-2.jpg


DZR ball valve

DZR%20Ball%20Valve%20ASAP.jpg


Both the same BSP thread size

(Useful also to have a lock nut so that the valve can be positievely locked on to the skin fittingin the required orientation.)

Lock-Nuts-ASAP-Supplies.jpg


Then a bronze hosetail, straight or angled as you require, male thread the same BSP size as the valve but also to match your hose bore

Straight-Hose-Tails-ASAP-Supplies.jpg


90-Degree-Hose-Tails-ASAP-Supplies.jpg
 
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Most will be 3/4 but toilet outlet will be 1 1/2. Holding tank may also be 1 1/2 and engine intake may be 1”. No need to worry about hull thickness for thruhulls as there is plenty of length on the threads. If you are replacing the whole lot, don't bother trying to take them apart, but just grind off the external flange and remove the complete assembly.
 
Most will be 3/4 but toilet outlet will be 1 1/2. Holding tank may also be 1 1/2 and engine intake may be 1”.

Maybe you're speaking with specific knowledge about Jeanneaux, but I wouldn't rely on those assumptions generally. Our boat doesn't have any 3/4" skin fittings - the heads outlet is 1-1/2", the cockpit drains are 1-1/4", both sinks (galley and heads) are 1", and the heads inlet is 1/2".

Pete
 
Does 1" drain OK? My galley sinks are 3/4" and drain like an old man.

Heh :)

Well, obviously 1" is going to drain better than 3/4". I've not really noticed the speed of draining, which I guess means it isn't a problem. The only issue I have is that the two sinks are interconnected immediately below the plugholes, so when I pull the plug on a full sink it "burps" up into the empty one as well as draining. If one sink is full of dirty washing up water and the other is full of clean plates draining then it's a bit annoying.

Pete
 
Are you sure you need to replace them ?
I have just replaced mine unneccesarily and wasted about £300 because I had bought bronze in advance
In hindsight I should have removed the first one (careful use of angle grinder from the outside to remove the flange and then pull the lot into the boat is easiest), and then looked how much of the section had de zincification ( the metal goes pink ) and then decided whether to simply replace that one or all the lot.
As someone said on this forum - "the safest job is the one you dont do"
Martin
 
On ASAP's advice, I used DZR for the skin fitting, valve, and tail. No need for bronze. Personally I thought it was better to use the same grade of metal throughout, as well as being cheaper.
 
On ASAP's advice, I used DZR for the skin fitting, valve, and tail. No need for bronze. Personally I thought it was better to use the same grade of metal throughout, as well as being cheaper.

There is another, recent thread about the new ASAP DZR fittings. They look excellent to me and could be considered better than the bronze valve option, which has a plated brass ball and possibly a brass stem. The DZR valves have a stainless steel handle, addressing one of the common objections about lesser types that have a rusty steel one.
 
Are you sure you need to replace them ?
I have just replaced mine unneccesarily and wasted about £300 because I had bought bronze in advance
In hindsight I should have removed the first one (careful use of angle grinder from the outside to remove the flange and then pull the lot into the boat is easiest), and then looked how much of the section had de zincification ( the metal goes pink ) and then decided whether to simply replace that one or all the lot.
As someone said on this forum - "the safest job is the one you dont do"
Martin

I am renovating my Jeanneau 43 DS after 10 seasons of South Coast charter work. In the water 50 wks per year and 99%marina based. Mast is coming down and standing rigging replaced (may not be necessary but I think prudent). Consensus on here is that Jeanneau have used cheaper brass fitting for years and while they seem to last many report an amount of dezincfication. While the boat has been properly maintained and all the valves work OK (greased at every lift out) I think it sensible to replace them now.

I am likely to retire and spend more time sailing so a budgeted expense now is better that an emergency spend in 5 yrs time.

I can re-veneer the floor at my lesuire and it is just cosmetic but to me failure of a skin fitting or standing rigging could be catastrophic and sensible preventative maintenance even if not essential right now is not money wasted!

I might feel different if others had reported Jeanneau skin fittings not showing some signs of dezincification and certain that DZR fitting had been used in the first place.
 
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Most will be 3/4 but toilet outlet will be 1 1/2. Holding tank may also be 1 1/2 and engine intake may be 1”. No need to worry about hull thickness for thruhulls as there is plenty of length on the threads. If you are replacing the whole lot, don't bother trying to take them apart, but just grind off the external flange and remove the complete assembly.
The last sentence offends my innate sense of frugality - at least try to remove them by unscrewing before you resort to the angle grinder! They often come off without trouble and you don't risk damaging your hull.
 
The last sentence offends my innate sense of frugality - at least try to remove them by unscrewing before you resort to the angle grinder! They often come off without trouble and you don't risk damaging your hull.

Sailfree intends replacing all the yellow metal fittings. Why struggle to get them out in pieces when 2 minutes of careful use of an angle grinder or a hole saw will do the job? He will be an expert by the time he finishes!
 
Arn't jeanneau ones sikaflexed in from new.

Can anyone advise?

There will be a sealant, but the skin fittings are held in with a locking nut as shown in Vics post earlier. To dismantle them you need to remove the hose, unscrew the valve and unscrew the backing nut then bash the fitting out. If you do one this way you will understand why external flange removal method is advised.

BTW makes sense to replace all the hoses at the same time, particularly the loo/holding tank outlets as you are part way there with what is usually a horrible job.
 
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