compression post and storage

[slowshoes]

  I am still in the middle of refurbing my new to me 1981 16 and have a couple quick questions.
I need to temporarily remove the compression post. I removed the two through bolts near the base - I figured this would allow the post to drop down and be removed. Even with the bolts out, the post seems just as secure. Is there something holding it at the top as well - maybe a lag bolt under the mast step? I figured before I get in a wrestling match with it, It'd be best to post for answers here.

  My other question is in regard to the area just forward of the compression post. It seems like it would be a good spot to add a bit of storage. The previous owner must have wanted to see what was there as well, as there is a 3/4 inch hole drilled in that forward area. I stuck a screwdriver down the hole and it didn't go very far before hitting what seems to be the same foam that is under the cockpit sole. Any idea what the foam is there for? Doesn't seem to be near enough to serve as flotation. Anyone converted this area to stowage?

  Thanks for any help.

    Fair winds,
     Bill

[wes]

Bill - although I have a 19, I believe the boats are similar in this area. On my 19 there is a single wood screw through the deck into the top of the compression post. It's too small to serve any structural purpose, so I assume it's there to keep the top of the compression post from sliding around when the mast is removed (believe me, when the mast is in place and the rigging is tensioned, that compression post isn't moving anywhere except possibly straight downward). To get to this screw you will probably have to temporarily remove your mast tabernacle. If your boat is a 1981, it's probably a good idea to remove and re-bed the tabernacle hardware anyway.

You are right about the foam - it is not intended to provide positive flotation. It's my understanding that the factory put it there for sound deadening reasons primarily - to reduce water/hull noise. On my boat, some previous owner cut a relatively big opening in the plywood just forward of the compression post (about 12" x 12" square) and then cut out a section of foam in order to reach the hull and drill a hole for a through-hull depth transducer. It's a good spot for that - maybe 12" forward of the keel and 12" off to the port side.

Wes

[skip1930]

Bill asks, " Any idea what the foam is there for? "

Only to keep the hull quiet when pounding into the waves. And a bit of stiffening for slings.
I don't think on a CP-16 that there is enough space once the foam is removed to make it a viable storage area.

It's worth it on a CP-19 though. Can't help you on the 'other' end of the compression post. As the two lag bolt screws are out try a rubber hammer at the cabin top and see what happens...

skip.

[slowshoes]

  Thanks for the replies wes and skip. Wes your probably right about my mast tabernacle being due (probably overdue) for a rebedding. I have to worry about rain today, but we have a good forecast for the next couple of days, so I'll give it a go then.

  I remember reading on another thread that the tabernacle shouldn't be through bolted (although I have to tell you, it seems like it should be) - so I shouldn't be surprised to find it just screwed down?

  Thanks for any further advice.

  Fair winds,
  Bill

[buckaroo]

I can confirm that on a 16 there is a long bolt underneath the tabernacle, through the mast step into the compression post.  I had to rebuild my step area after significant water penetration into the small plywood core of the step, so I know the anatomy there a little better than I'd like. 

[wes]

Bill - if you attach your tabernacle to the deck with screws and (God forbid) you get dismasted someday, you will probably have four holes to fill with epoxy and re-drill. If your tabernacle is through-bolted nice and strong and you get dismasted, you will probably have a honking big hunk of your deck ripped out, which is a serious repair job. That's why the factory uses screws.

There is really no advantage to through-bolting, since there's very little stress on the attachment point when the mast is up. The rigging would probably hold it in place almost as well if you used double-sided sticky tape

Sometimes stronger is too strong.

Wes

[slowshoes]

  Thanks again for the replies guys - a big help. Buckaroo - hopefully I won't need advice on rebuilding the step area after removing the tabernacle!

         Fair winds,
          Bill     

[Rob]

I sure do wish that some people would keep there fingers off the key board when they relay don't know what there talking about.The foam is there to keep you afloat should you ever take on water. I wonder if my 1979 com pac 16 will have enough to keep me up if needed?The compression post is bolted on the bottom and has 4   1 1/2 inch screws coming from the top thur the tabernacle and cabin top into the top of the post,be very carefull when separating the post from the cabin top because some old boats are balsa cored and its not easy to repair and old sealant and glue gets between the post and cabin top sometimes is hard to remove . something to think about adding when the tabernacle is up is a deck plate under it before putting it all back together,its a nice way to run lines down and then aft. Just some to think about. Rob

[Craig]

See post "Foam in the boat" by MacGyver. Probably applies in this instance also.

[Pamelina]

I remember reading on another thread that the tabernacle shouldn't be through bolted (although I have to tell you, it seems like it should be) - so I shouldn't be surprised to find it just screwed down?

Hi Bill, well that made me shudder. Check out my post about what can happen:
http://cpyoa.geekworkshosting.com/forum/index.php?topic=5758.0

We just replaced our compression post and there is a screw under the tabernacle as well as a bolt at the base. I talked to Hutchins about the replacement and he said the new one could touch the keel, even though they were not built that way.

Hope this helps. Good luck with your repairs.
Pam

[slowshoes]

  Pam, Thanks for the info. So sorry about your dismasting and subsequent damage to your boat.   At least no one was hurt - things certainly could have been much worse. Your pics of the damage to your boat certainly puts an exclamation point on screwing down as opposed to through bolting the tabernacle.

  I'm not sure if I should get involved with removing the tabernacle now or wait until spring. We're supposed to have highs in the 40's this weekend - not the best temps for most bedding compounds. At any rate, thanks again for the info and good luck with your repairs as well.

   
              Fair winds,
               Bill

[Smier]

Bill - if you attach your tabernacle to the deck with screws and (God forbid) you get dismasted someday, you will probably have four holes to fill with epoxy and re-drill. If your tabernacle is through-bolted nice and strong and you get dismasted, you will probably have a honking big hunk of your deck ripped out, which is a serious repair job. That's why the factory uses screws.

There is really no advantage to through-bolting, since there's very little stress on the attachment point when the mast is up. The rigging would probably hold it in place almost as well if you used double-sided sticky tape

Sometimes stronger is too strong.

Wes

My 16 was dismasted during a bad wind storm while docked at its seasonal slip by the previous owner, and after seeing and repairing the damage firsthand, I see no reason not to thru bolt it!  The weak point on my 16 was the flimsy tabernacle, which simply bent one of the ears over when the mast flopped to the side when the standing rigging failed.  It did not pull out of the top of the cabin, the previous owner actually had to unscrew it to remove the tabernacle from its mount.  I could see it ripping the fiberglass and block apart if the area was already rotten, but not if it is in good shape.  Mine is now thru bolted with two long stainless bolts with giant washers and nuts in the cabin and two long stainless screws that actually go directly into the compression post.  The mount is much stronger than the stainless sheet metal tabernacle Hutchins originally equipped our boats with.  I have also seen it first hand while practicing raising and lowering the mast single handed, I lost control of the mast and it simply bent the tabernacle over, didn't even budge at the base.  The original tabernacle on my 1980 is so flimsy you can bend it by hand, not sure if later models were different or received beefier tabernacles?

[Smier]

I "borrowed" Pamelina photo to try and show what I mean.  When theirs was dismasted, by not being thru bolted into the compression post, it allowed the top of the cabin to flex until the point that the fiberglass couldn't give anymore and it tore... I will argue that if the tabernacle was thru bolted into the compression post, the tabernacle would have bent, but not tore off because it is now one with the compression post.  On my CP16 only two of the 4 bolts are drilled thru and bolted with washers and nuts, the other two are thru bolted with long stainless lag screws into the compression post.  My compression post also appears to be much larger than the one in hers pics, hers looks to be nothing more than a 2x4 that someone had replaced the original compression post with, I would use at least a 4x4 post if I were replacing mine.

[Pacman]

The Tabernacle can do some serious damage if a shroud lets go and the mast comes down as the above photo shows.

If it is simply screwed in place it will just pull out the screws and bend the Tabernacle.

I removed the Tabernacle and replaced it with a rotating mast base like the ones on my catamarans and my Butterfly sailboat.

With my set up, if a shroud lets go it won't do any damage to my boat.

I can't seem to post photos but I could email some if another member could post them for me.

[Pacman]

The foam is there to keep you afloat should you ever take on water. I wonder if my 1979 com pac 16 will have enough to keep me up if needed?

A liter of foam will displace 2.2 pounds of water.

My boat weighs about 1,000 pounds.

I don't have any where close to 450 liters of foam in my C 16.

It would sink if full of water.