• Announcements

    • Zapata

      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

Archived

This topic is now archived and is closed to further replies.

PNWsailorGuy

Another lifting an FT10 idea

Recommended Posts

Is it possible to use the engine mount where the engines slides into the water as the aft triangulated lifting point? This seems like a strong part of the boat. New hinges would have to be installed that would allow the engine hatch cover to be easily removed so that the webbing from the lifting point would be able to angle toward the hook of the crane.

 

So the questions are:

  1. Will the engine mount support the triangulated weight?
  2. Is there a hinge that can be installed so that when the hatch cover is lifted it can easily be removed from over the engine to expose the lifting points on the engine mounts?

 

Can it be done?

 

If this line of lifting has been explored please let me know.

 

PNWSG

Share this post


Link to post
Share on other sites

Why not just add a lifting eye to the transom - I remember the previous builder of the boat being very proud that you could hang the Tiger by the tail

Share this post


Link to post
Share on other sites

going to a transom lifting point the angle of the bridle would be too shallow, allowing rotation, if the keel lifting point is used. A steep angle would be better for control. If the hull is going to be supported by the keel bulb, then the amount of weight should be minimal ( enough to keep the boat from rotating / transom dropping ) as the boat is lifted. ( some are using a few water filled 5 gal jugs on the bow for balance ) I'm thinking the the fairleads moved aft on the jib track should be strong enough and allow for a good angle to the keel lift point to keep the transom from rotating down. ( The fairleads and jib track are rated for a few thousand pounds of load while the load to balance would less than a couple hundred pounds )

Share this post


Link to post
Share on other sites

going to a transom lifting point the angle of the bridle would be too shallow, allowing rotation, if the keel lifting point is used. A steep angle would be better for control. If the hull is going to be supported by the keel bulb, then the amount of weight should be minimal ( enough to keep the boat from rotating / transom dropping ) as the boat is lifted. ( some are using a few water filled 5 gal jugs on the bow for balance ) I'm thinking the the fairleads moved aft on the jib track should be strong enough and allow for a good angle to the keel lift point to keep the transom from rotating down. ( The fairleads and jib track are rated for a few thousand pounds of load while the load to balance would less than a couple hundred pounds )

 

 

Surely the object of pulling the lifting sling/cable aft relative to the hull is to ensure that the lifting point is above or aft of the CoG of the boat so that the transom is higher than the bow to ensure that the lifting cable doesn't foul the mast head. The "aft pulling" string should be secured as far aft as possible as this reduces the load on the string.

 

Alternatively if you can't actually pull the lifting cable aft, then fixing the "aft lifting" string as high up the lifting cable as possible and as far aft as possible reduces the load on it.

Share this post


Link to post
Share on other sites

going to a transom lifting point the angle of the bridle would be too shallow, allowing rotation, if the keel lifting point is used. A steep angle would be better for control. If the hull is going to be supported by the keel bulb, then the amount of weight should be minimal ( enough to keep the boat from rotating / transom dropping ) as the boat is lifted. ( some are using a few water filled 5 gal jugs on the bow for balance ) I'm thinking the the fairleads moved aft on the jib track should be strong enough and allow for a good angle to the keel lift point to keep the transom from rotating down. ( The fairleads and jib track are rated for a few thousand pounds of load while the load to balance would less than a couple hundred pounds )

 

I think your math may be off on this - though I am no expert. I amount of weight people are loading on the bow is at least 200 lbs which is 15 ft forward of the center of gravity, so the force closer to the cg is much higher.

 

It seems to me that if you have 200 lbs on the bow (which is about/at least 15 feet forward of the center of gravity) the torque force you are creating is 3,000 ft-lbs of torque. (Force x lever arm = torque) If you were to lift just 3 ft behind the cg then the lifting force would be 1,000 lbs. (3000 ft-lbs/3 ft = 1000 lbs.) The further back the lifting point, the less vertical force required.

Share this post


Link to post
Share on other sites

going to a transom lifting point the angle of the bridle would be too shallow, allowing rotation, if the keel lifting point is used. A steep angle would be better for control. If the hull is going to be supported by the keel bulb, then the amount of weight should be minimal ( enough to keep the boat from rotating / transom dropping ) as the boat is lifted. ( some are using a few water filled 5 gal jugs on the bow for balance ) I'm thinking the the fairleads moved aft on the jib track should be strong enough and allow for a good angle to the keel lift point to keep the transom from rotating down. ( The fairleads and jib track are rated for a few thousand pounds of load while the load to balance would less than a couple hundred pounds )

 

 

Damn you are a little slow - it was a joke..................

 

 

TigerByTail1.jpg

Share this post


Link to post
Share on other sites