Water tank install? Inside water ballast tank

[March]

Nah, you can get a military unit on flea-bay for 200 bucks. That's what we paid for ours--150, in fact, if memory serves.It was supposed to be "expired," but it worked just fine. And the ten gallons at hand were in bladders--we never managed to run them dry, even though we had a solar shower, too. By the time we returned to Florida, one still had the original water--funny smell and all.

[Divecoz]

Ixneigh: Are you saying you pulled the cushions out of the rear berth? Then you removed those white panels that cover the " bilge / storage" area and when you kneeled on the bottom of the boat it flexed?? Humm the bottom of the M is about? 5/8 = 3/4" thick Fiberglass.... Dude just how much do you weigh?? Now I am going to make a guess.. You were not kneeling on the hull but on the top of the water ballast tank..
I have drilled numerous holes below the boot stripe on this boat and, I was amazed how thick it is.... I still have the holesaw sluggs..

[Ixneigh]

Divecoz: yes that is what I did, the first night I had the boat, drying up all the water in the bilge compartments. And I weigh 150.
Then on the trailor i saw the bottom is in fact much thicker, fine even by my standards. What is the "bottom" of the back berths is actually the top of the rear water ballast tank. That's why drilling holes near the stock battery box location is a bad idea. The battery seems to be just at the forward end of the tank.

March: oh that's very interesting to know. I've seen those on eBay before. I might have to try one. I'd take a chance for a couple hundred bucks if someone else has tried it.
I would still want to execute this mod if possible. I would like to have a cockpit wash down for my two dogs. Even a 10 gallon tank means no more Jerry jugs everywhere and more under sink storage without the camping tank the boat comes with.

[Seapup]

While I like the idea, replacing water with water, something for nothing, its is a lot of work for a problem that has so many viable easier proven solutions.

[Divecoz]

I am getting VERY Confused ...Help me out.. The dog wanted out so ...out she went. I was looking at my boat on her trailer in the Driveway.. 4000lbs is supported on the trailer by less than 10' of carpeted 2x4's and there is No Hull Deflection.. I got some time left as the dog wont bark to come in for a few more minutes , so I grab my mechanics crawler and I scoot from one end to another , under the boat. I POUND on the bottom of The Hull , stim to stern.. She is rock solid!
Now allow me to ask because I am still confused? Are you removing some of the volume of the ballast tank with this Mod? We need every Ounce that's there.. These boats are tender as they come from the factory? I for one don't see any advantage for all the work.. If you don't want more weight in the transom area put it amid-ships.. don't like that ? Put it in the V Berth.. ?

[Russ]

I POUND on the bottom of The Hull , stim to stern.. She is rock solid!
Now allow me to ask because I am still confused? Are you removing some of the volume of the ballast tank with this Mod? We need every Ounce that's there.. These boats are tender as they come from the factory?

He is saying that in the aft berth area, above the bottom hull is a another layer of glass that makes the top of the ballast tank. That the tank under the aft berth is made of 2 layers of glass. The bottom hull being solid as you described, and inside the boat is another thinner layer that is the top of the tank.

He doesn't want to remove any water, just replace raw sea water with fresh potable water.

___________________________________
xx <bladder> xxxxsea waterxxxxxxxxxx /
_________________________________/




--Russ

[Divecoz]

Thank You Russ I am just getting OLD I guess.. OK replacing polluted water with potable water? These boats must have , either Full or Empty " Ballast" how does that work ? In my bladder there is really no side to side weight changes / transfers.. because its collapsible and finds its own level..and its mounted on the Centerline of the boat..

He is saying that in the aft berth area, above the bottom hull is a another layer of glass that makes the top of the ballast tank. That the tank under the aft berth is made of 2 layers of glass. The bottom hull being solid as you described, and inside the boat is another thinner layer that is the top of the tank.

He doesn't want to remove any water, just replace raw sea water with fresh potable water.

___________________________________
xx <bladder> xxxxsea waterxxxxxxxxxx /
_________________________________/




--Russ

[K9Kampers]

Or fill ballast tank with beer... sail to Bahamas for the winter... return when beer is gone, but with seawater ballast!!

[Russ]

Thank You Russ I am just getting OLD I guess.. OK replacing polluted water with potable water? These boats must have , either Full or Empty " Ballast" how does that work ? In my bladder there is really no side to side weight changes / transfers.. because its collapsible and finds its own level..and its mounted on the Centerline of the boat..

Well, as I understood his opening post; he wishes to cut a section out of the top of the ballast tank (under the aft berth area). Insert a bladder water tank in that space, connect fill/drain tubes, then seal the ballast tank cutout back up.
To use the fresh tank: Fill the bladder with fresh potable water. Then fill the ballast tank with sea water. Full ballast as the space has no air or voids.
When you draw fresh water from the bladder, replace the space it occupied with sea water, thereby maintaining the full weight of water ballast.
A beer bladder might work well at keeping the beer cold, but how do you keep the carbonation?



top of ballast tank
_______________________________
....sea water...........................
<FRESH WATER BLADDER>----------------fill hose
....sea water...........................
_______________________________
bottom of hull

[Divecoz]

Thanks Russ.. I get it now.. Old Dogs learn slowwwwwwwwwwwwwwww
OK Now That I understand.. forgetaboutit..too much work.. too much expense.. little to Nothing is gained.. " IMHO" which BTW ain't worth much lately.. As some are aware..
We have been sorting reducing saving and eliminating "stuff" for several days here.. We are moving from a 3500+ sq ft House and a 640 sq ft Garage to .. 1800 sq ft house and a 435 sq ft garage... This time.... so I am told!! That garage WILL ... allow for Her Car to fit in it, for the first time in 24 years.. Hummmm Seems My Humble Opinions? Carry Very Little Weight ..

[Sumner]

.... Having 30 gallons of fresh water without adding a single extra pound of weight is very cool.

First this is a mod I wouldn't attempt, but if he can pull it off it sounds like some of the rest of you might try it. I'll be interested in seeing pictures of it. I'd for sure want to be able to get the bladder out if needed, but sounds like that is planned for.

I realize that one of the projected pluses of this mod is that fresh water won't add weight to the boat but we really like the extra weight down low in our boat. 40+ gallons of water, 19 of fuel and lots of can goods and such down low has made our boat much more comfortable in heavier seas. It punches through the waves better vs. hitting them and then riding up and slowing.

I'm sure the extra weight probably hurts in light air or when having to do short tacks and accelerating off of each one, but for long runs it might even help since the boat has a little more length at the waterline and you might be able to carry more sail with more righting moment down low. Ruth and I will never know as we aren't aggressive sailors, but we can tell that the boat is more stable now sitting a couple inches lower in the water,

Sum

===================================
Our MacGregor 26-S

Our Endeavour 37

Our Trips to Utah, Idaho, Canada, Florida

Mac-Venture Links

[Divecoz]

Though Maybe .. My 20=30 gallons of potable water would help me sail better, if it was amid ships? Or Maybe further forward? But I like Sumner, have never sailed edgy enough to realize a difference.. Good or Bad... Mine is ONLY a very few inches above the proposed location and those 240 lbs can only hurt when motoring. Ahhhh That is only if I don't dump my ballast..
OK if I am understanding this project? You are going to cut out the top of the water ballast tank open. You will then fiberglass a collar in place to provide for a place to secure your potable water bladder to sit.. You will then replace the missing top , for the remaining water ballast? What Have You Gained? If we both dump our ballast and retain our potable water ? Our weight remains too close to measure.. With both our ballast full and our bladders full I will weigh about 240 lbs more than you do.. I may or may not sail faster? However I "should" and I feel I do, ride better due to my extra weight below the water line.. What am I missing??
As Sumner says:

I realize that one of the projected pluses of this mod is that fresh water won't add weight to the boat but we really like the extra weight down low in our boat. 40+ gallons of water Sum

[Divecoz]

@#$%^&* I went back and read this all again.. If understand Russ .. The bladder is now part of the ballast tank?? No way to easily repair anything involved with the potable water tank..
as per the explanation... "" When you draw fresh water from the bladder, replace the space it occupied with sea water, thereby maintaining the full weight of water ballast. "" this sounds even more prone to failure and issues.. Issues now with potential / Inevitable contaminated potable Water??
OK I will step away from this prtoject as I see No advantage anywhere in this project.. So I guess thhis will be just another to each his own..

[raycarlson]

this whole thread tells me we have way to much spare time on our hands to be pondering these far-fetched idea's. My 25cents says this mod will never see the light of day. way over involved just to add a little water capacity.

[Russ]

This is a mod that I would never attempt. Actually, there are many mods beyond my skill set. But I salute those with the free time to do them and make some amazing changes to their boats. From Highlander's bowprits (and then some) to Currie's cabin and cockpit extension.

Since many of us use our boats for more than day sailing and the Mac is not really configured for cruising many of us are forced to be creative. Several areas seem to be of great challenge: Refrigeration, electric power, sanitation and potable water seem to be the most common. Next up seems to be air conditioning. One of the best benefits of this forum is learning how others have overcome these challenges and devising your own solutions from theirs.

Erik's electric anchor
http://www.macgregorsailors.com/forum/v ... =8&t=12983&

Currie's cockpit extension
http://www.macgregorsailors.com/forum/v ... =8&t=13570

All ideas that I would never do, but I'm in awe of their abilities to make them work. So, this is one I really would love to see happen.