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Correcting fore and aft trim

Discussion in 'Ask All Sailors' started by smokey73, Jan 9, 2017. Add this thread to a FAQ

  1. smokey73

    smokey73

    Joined Oct 26, 2010
    436 posts, 51 likes
    Hunter 40.5
    US Beaufort, SC
    Last year I installed a 5.5 KW generator in my starboard lazarette and moved my batteries to the port side. Needed to keep the Admiral happy by being able to run the AC when away from the dock at least long enough to cool the cabin down after a long hot day in SC. "If Momma ain't happy, ain't nobody happy."

    With that extra 275 lbs or so my stern now "squats" considerably and is even more pronounced when running under power. I have stored a spare CQR anchor (about 40 lbs) forward under the V-birth. Even with the forward water tank full (also under the V-birth) and the aft water tank empty, it does not sit on its lines. The boat displaces about 20,000 lbs or a little more.

    I need to get her back on her lines. I know that most people, myself included, don't like to just add dead weight, especially to the bow or stern but that seems to be the only solution. I am planning on first getting sand bags and figuring how much will be needed to get the trim right by trial and error. Once that is determined I'll either leave the sand bags in place or switch to something denser like lead shot in bags. I guess I could add some batteries in the bow but then its 40+ feet to the other batteries and I would think that might cause uneven loading/charging problems and I'm not sure I want the possibility of Hydrogen generation up there (I know I could get AGMs but I prefer to stick with lead acid for the time being). I could put a water bladder up there but we never use all our water anyway so I don't see the advantage of that right now.

    I can't think of anything else dense enough to store there to do much good except beer, but then its not a good place to keep that much beer and I'd have to replace beer as I take it out. Too much work!

    Any thoughts or suggestions would be appreciated.
     


  2. Justin_NSA

    Justin_NSA

    Joined Jul 7, 2004
    3,910 posts, 366 likes
    Hunter 30T
    US Wichita, KS
    I think you are on the right track. More batteries, preferably AGM or what else out there that doesn't outgas would be best. From what I (think) I know, they don't like to be mixed with other types though.
    If you use the right gauge cable, I don't think your system will see the extra length. The hard part is running it thru the boat.
    In the old days you could shift your powder and cannonballs forward to trim out
     


  3. smokey73

    smokey73

    Joined Oct 26, 2010
    436 posts, 51 likes
    Hunter 40.5
    US Beaufort, SC
    Another thought after figuring out how much weight I will need from the sandbags.

    I have a third spare anchor with easy access (a Danforth) for emergency deployment with about 10 feet of anchor chain and then a nylon three stand rode. It can be deployed fairly quickly. I already have about 80 feet of chain on the primary anchor with the remaining 100 foot or so of three strand rode.

    Options:

    1. Buy anchor chain for the spare anchor and store it under the V-birth. Amount of chain would be determined by the sand bag weight I determine brings her back on her lines. At least it would be useful weight.

    2. . I could go with an all chain rode for the primary and store the current 80 feet of chain and nylon rode under the V-birth. In fact, an all chain rode may be enough depending on how much the sandbags say I need.

    Thought?
     


  4. dlochner

    dlochner

    Joined Jan 11, 2014
    1,089 posts, 242 likes
    Sabre 362
    US Fair Haven, NY
    If you don't already have an all chain rode, change to all chain, that will add considerable weight in a useable item.

    Also is there anything on the aft end that can be removed?
     


  5. smokey73

    smokey73

    Joined Oct 26, 2010
    436 posts, 51 likes
    Hunter 40.5
    US Beaufort, SC

    I have already shifted all the cannonballs I have but my wife made me deep six the cannon since it makes people nervous when they cross our bow too close!!:cuss: Besides, Homeland Security and the Coast Guard seemed to take an additional interest in the boat with the cannon on board. :liar:
     


  6. Justin_NSA

    Justin_NSA

    Joined Jul 7, 2004
    3,910 posts, 366 likes
    Hunter 30T
    US Wichita, KS
    Don't you hate all this government intervention !!
     


  7. smokey73

    smokey73

    Joined Oct 26, 2010
    436 posts, 51 likes
    Hunter 40.5
    US Beaufort, SC
    Nothing on the aft to remove. In fact I"d like to put a dingy there but I know it would only make things worse. I already keep the aft water tank just below the generator empty to reduce weight aft. I would only fill it on an extended cruise and then use the water from it first.
     


  8. Gunni

    Gunni

    Joined Mar 16, 2010
    4,350 posts, 565 likes
    Beneteau 411 Oceanis
    US Annapolis
    The most compact ballast would be a lead casting to fit some particular space forward. But your interim solution of lead shot or bars would be workable - just make sure you secure your ballast. A roll or knock down with loose lead is going to make almost as much a mess of you and your boat as if it came out the end of a barrel. Long term plan on moving all your batteries to someplace forward (and lash them down well). I found that simply relocating and installing AGM in the saloon to port was enough to get the boat back on her lines and evenly balanced on both tacks. Also have a 5.5 kW genset to starboard and was not interesting in giving a bunch of lead ballast a ride. The good news is having your batteries low and centered makes your boat sail better - so you have an incentive.
     


  9. Rich Stidger

    Rich Stidger

    Joined Feb 10, 2004
    2,571 posts, 128 likes
    Hunter 40.5
    US 1997 h40.5 Bristol, RI
    Dan,

    I have a 5 kw genset plus 4 golf cart batteries in the stern. The batteries are about 68# each and I think the genset is about 375#. I use all 170' 5/16" G4 chain rode (about 2#/ft I think) and a 45# Manson Supreme anchor. I do see a little stern squat but I don't judge it to be a problem. I also have a 100# dinghy hanging off the stern on davits. However, years ago I did adjust my water line to raise the top edge of the bottom paint so that it was always above the true water line. In doing so I may have raised it more in the stern than elsewhere. If I did that it, it would mask the apparent amount of squat.
    I would avoid adding weight to the bow. My understanding is that weight at the bow is detrimental to sailing performance.
     


  10. JRacer

    JRacer

    Joined Aug 9, 2011
    490 posts, 70 likes
    Beneteau 310
    US Wichita, Kansas Cheney KS (Wichita)
    Depleted uranium or Gold, take your pick! ;-)
    Depleted Uranium (DU) is for all effects and purposes the same as naturally occuring uranium, U238. The density of uranium or DU is about 19 gm/cm3, which is much denser than titanium (4.5 gm/cm3), diamond (3.5 gm/cm3), or quartz (2.7 gm/cm3). By contrast, lead (at 11.3 gm/cm3) is only just over half as dense as DU and even mercury (at 13.5 gm/cm3) is not quite 2/3 the density of DU -- uranium is amazingly dense, being very near that of gold (19.3 gm/cm3).
     


  11. Jackdaw

    Jackdaw

    Joined Nov 8, 2010
    7,160 posts, 1,122 likes
    Beneteau First 36.7 & 260
    US Minneapolis MN & Bayfield WI
    Ugh. I get what you are trying to do, but adding additional big weight to the bow of your boat to counter big weight you added to the transom is the worst thing you could do to your boat performance wise.
     


  12. Kermit

    Kermit

    Joined Jul 31, 2010
    3,603 posts, 816 likes
    Hunter 260
    US Sumter, SC Lake Murray Sailing Club, SC
    If you're by chance married to my ex-wife, just get rid of her. That would eliminate dead weight that shifts meaninglessly and eliminate the need for the heavy generator and all other additional ballast whether it's useful or not.
     


  13. markwbird

    markwbird

    Joined Nov 26, 2012
    674 posts, 99 likes
    Hunter 34
    US Berkeley
    Put another generator on the bow. Double the power, double the happiness. But seriously, folks. Weight at the ends of the boat is bad news performance wise. I would consider relocating the generator.
     


  14. Ron20324

    Ron20324

    Joined Jan 22, 2008
    5,556 posts, 352 likes
    Beneteau 323
    US Annapolis MD
    I'm surprised no one has suggested a couple of Bow Babes. Twins preferred, one on each side... for balance, you know.
     


    Kermit likes this.
  15. Kermit

    Kermit

    Joined Jul 31, 2010
    3,603 posts, 816 likes
    Hunter 260
    US Sumter, SC Lake Murray Sailing Club, SC
    I imagine that would be subject to his wife's approval. But I'm sure all of his homies on the forum would readily approve. Especially if he sends pictures regularly.
     


  16. Johnb

    Johnb

    Joined Jan 22, 2008
    998 posts, 62 likes
    Hunter 37-cutter
    US Richmond CA
    On my boat it seems that the slight squat at the stern increases when motoring (always with any boat) and disappears when sailing. This is intuitively logical as the net result of all the forces in the direction of motion is above the boat and tends to push the bow down. So I just ignore it.
     


  17. markwbird

    markwbird

    Joined Nov 26, 2012
    674 posts, 99 likes
    Hunter 34
    US Berkeley
    How much to the batteries weigh? I moved mine to the port side under the salon settee right about mid-ship specifically to improve balance. Easier to access as well.
     


  18. Justin_NSA

    Justin_NSA

    Joined Jul 7, 2004
    3,910 posts, 366 likes
    Hunter 30T
    US Wichita, KS
    If bow babes are not acceptable, perhaps a nice figurehead
    [​IMG]

    or

    [​IMG]
     


    Kermit likes this.
  19. Kermit

    Kermit

    Joined Jul 31, 2010
    3,603 posts, 816 likes
    Hunter 260
    US Sumter, SC Lake Murray Sailing Club, SC
    Decisions, decisions.
     


  20. Jackdaw

    Jackdaw

    Joined Nov 8, 2010
    7,160 posts, 1,122 likes
    Beneteau First 36.7 & 260
    US Minneapolis MN & Bayfield WI
    I've been working with Jo on the value of mass centralization. Down low and centered. You know, a racing thing. Seems to be working.

    FullSizeRender (3).jpg
     



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