My MacGregor 26D has a ferro-cement ballast. Please Help.

[finding41]

So I have found out what the patch was for in my V berth. It was hiding the cement that someone (PO) put in the ballast tank! Then glassed over...:cussing:
Here is the question. What do I do now? I know that the 26D can use a bit of extra weight in the front but this is kind of nuts. I would love suggestions.

You can see a few short videos on my YouTube channel "finding41" and in another thread " What is in my V berth?"
1 st pic. Patch I found under a loose fiberglass patch. And the 3 bolts holding the chunk O ferro-cement.... from sliding further back into the ballast tank. (I think)
2 nd pic. gravely bits between the top of the ballast tank and the hump O ferro-cement and fiberglass in the front of he tank.
3 rd pic. The spot where the hump O ferro.... terminates in the ballast and the loose resin on the bottom. About 3" back form the rear edge of the hole. (The rear edge of the is approx. 6-7" from the hull liner.)

 

[Ross]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

Got a jack hammer and a shop vac? open things up and break up the concrete and vacuum it all out.

 

[Sumner]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

If you can still get the water ballast in and out and it doesn't leak and the concrete is stable I'd try it. Our boat probably isn't as fast as others in light air if you have to do frequent tacks, but we like the feel of the boat when we have it loaded with a month's provisions. Not necessarily with respect to heeling, but is feels better pounding through waves.

Give it a try,

Sum

[FONT=Arial, sans-serif]============================[/FONT]

Our Endeavour 37

Our MacGregor 26-S Pages

Our Trips to Utah, Idaho, Canada, Florida

Mac-Venture Links[FONT=Arial, sans-serif][/FONT]

 

[finding41]

I was thinking of trying it this year. Then remove it if I thinks its going to be a problem. I'll hold off painting in there this season. The tank will still hold about 95% of the water that was intended. It looks to be about 2 bags of ready mix in the way of amount of cement. I think, judging by the area that's filled.
Here is a picture looking back in the ballast. It looks clean. I removed the chunk of the patch in the picture.

 

[kenn]

I was thinking of trying it this year.

yeah, just sail it and see. I don't think it's worth the effort to remove unless it has seriously compromised the boat's safety or sailing characteristics.

 

[mitiempo]

I would just sail the boat and see how it does. Probably just cement as ferro-cement would mean there is steel in it. Makes for a bit heavier boat when trailering though. The cement is in the location where the water ballast goes - correct? Cement without steel in it weighs about 94 lbs a cubic foot vs water at 60 - 64 depending on salt content. It shouldn't add much weight over the water that would normally be there. How much do you think is there?

Profile of your boat showing ballast tank location

 

[Sail123]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

That is a mod the folks at macgregor sailors could be helpful about That is a mod happy bunch. I remember reading about that there, when I owned a Mac 25.

 

[RobertLangdirect]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

Finding 41 -- related to the cement and another post about the trailer weight, how does it ride on the trailer? My son has a Macgregory 17 and without any weight on the nose, it has almost negative weight on the trailer tongue. I wonder if the PO of yours found this true of the 26 and decided to fix that, permanently?

Do you know the PO? Can you ask the PO what's up?

 

[RobertLangdirect]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

Two 60 pound bags would be how much?

 

[MrBill_FLL]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

this is a racers cheat, mod.

they want more righting movement than plain water, cement is the cheapest way to do that. I know of at least one boat that was cut like your's and 50# of lead was added, and reglassed.

its an outright cheat, or fracture of the rules if you don't notify the race committee and get your ratings adjusted.

-but unless you are racing, no big deal.

-as long as the cement stays put. if it breaks up, it could clog the drain holes, so keep an eye on that.

seal it up and go sailing!

 

[MrBill_FLL]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

in the nose (bow) would be where I would put it... since you have plenty of crew in the back when racing.

 

[MrBill_FLL]

Two 60 pound bags would be how much?

is that a trick question? 120 pounds

 

[MrBill_FLL]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

^ this is what you meant... right?


http://www.eng-tips.com/viewthread.cfm?qid=187874

The 700 pounds of concrete will have about 4.2 cubic feet volume. Thus, a displacement of 301 pounds of water and a net downward weight of 399 pounds.


(so in your example, about 60# net more) * depending on the mix!

 

[MrBill_FLL]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

http://wiki.answers.com/Q/How_much_does_concrete_weigh_per_yard_underwater

http://lmgtfy.com/?q=how+much+does+concrete+weigh+underwater

 

[Squidd]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

A 60# bag of redi mix is about 1 cu/ft...

 

[finding41]

I put the cemented area into the line drawing. Its the red spot.

 

[mitiempo]

It should be fine - it can't be adding that much weight over water as the area is fairly small.

 

[MrBill_FLL]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

that's where I would put it!

What this means, is you can carry more sail in higher winds longer... since you have more ballast than the 26D next to you... so you are faster because he's heeling too much.

in light wind, it means you are just heavier, but not enough to really notice unless racing.


-are you planning on racing the boat? I'd just have a coat hanger in the tow vehicle incase one day the cement starts to break up, and clogs the drain hole. then poke the holes in the drain. till water comes out.

-is it one nice solid piece still? (can tell from the pic)

 

[Scott T-Bird]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

Wow! The numbers flying around are really screwed up (even including that blog thread). The weight of unreinforced concrete (which includes Portland Cement, sand and gravel) is 144-145 pcf (Portland Cement - the bonding agent in concrete - weighs just 94 pcf). The weight of water is 62.4 pcf. These facts are easily looked up and ingrained in most engineer's minds. Concrete with steel reinforcing is always figured at 150 pcf.

A 60-pound bag of concrete mix is figured at 0.45 cubic feet (obviously water is added to bring up the total weight just a bit - that's why the concrete when cured will weigh about 65 pounds for a bag mix) based on suppliers information. This can also be looked-up.

You probably have about 130 pounds for 0.9 cubic feet of concrete if they used 2 bags (just less than 1 cf). The water it displaces weighs 56 pounds based on the assumed volume so you have about 75 pounds of extra weight in the nose of the boat.

This slightly affects your carrying capacity (960 pounds minus 75 pounds) which is published information from MacGregor. Also, according to Practical Sailor, boats with water ballast have a tendancy to hobbyhorse a little due to the displacement being spread across the length of the boat as opposed to centralized in the middle so you may find the added weight near the bow affecting this characteristic.

Then again, you may not notice it at all. It's just 75 pounds more and is no different than stashing a bunch of stuff in the forward berth.

 

[finding41]

Re: My MacGregor 26D has a ferro-cement ballast. Please Help

So it may be an advantage to keep it there. I'll glass it up when I get time.
Mr Bill, mums the word when it comes to racing.
It kind of hobbyhorses with the trailer now when I climb on the back and with the tongue of the trailer extended about 4' it feels like about 200Lb when I have to lift it.