Removal of Compression Post....?

[mayrel]

Greetings, I'm a new member and we are toying with obtaining either a Compac 19 or 23.  With that said, I read there was some issues with the compression post on the 19's; specifically the mounting bolts were bent and the post is not mounted through to the keel.  No one seemed to be concerned, so I suppose this isn't a real issue?  With that said, I'm curious if it would be possble to eliminate the compression post, and replace it with a fabricated SS support that would be fitted to the cabin ceiling, follow the cabin top to the hull, and be secured with through bolts to the gunwales?  Or possibly under the side decks with an appropriate SS backing plate?  This would seemingly provide the same support that is provided by the existing compression post(considering it isn't mounted solid to the keel, it needs to flex a bit anyway?).  It would also provide for more useable space in the cabin.  I would appreciate any and all comments/suggestions on this issue; you can email me directly at mayrel@hughes.net  early thanks....John

[Paul]

Hi John.  Welcome to the forum.  Very interesting question.

I posted some info a while back about my 16 and her issues with a rotten bulkhead where the compression post attaches.  As far as I know, both the 16 and the 19 have a short bulkhead that reaches across the boat beam-wise.  It is tabbed in place with fiberglass.  But, some plywood may be exposed.  The compression post is bolted to the bulkhead and does not rest directly upon the keel.  It is also attached to the cabin top with a large wood screw mounted from the outside of the cabin roof down through the compression post.  On my 16, it is sealed with silicone caulk and hidden by the tabernakle.  On my 16, water found its way to the bulkhead, where it did it's damage.  The compression from sailing did elongate the bolt holes a little.  I don't think I was ever in danger of loosing the rig, though.  The deck is not cored and therefore is pretty rigid.  I chose to replace the bulkhead and re-attach the post.

You've probably seen some photos of the 23 set up.  It has a much more substantial bulkhead with "posts" on either side of a doorway.  I like that set up, too.

As I re-read your post, it sounds like you are considering replacing the compression post with a metal "bulkhead" that is essentially hung from the ceiling and attaches to the hull sides.  If so, then I'd be concerned about the downward forces pushing outward on the hull sides.  This may not be the best for the integrity of the hull.  However, if you extended it down to the bottom of the hull and keel, it may work.  But, I am guessing you are trying to come up with ideas to prevent you from having to do that much to the boat.   I am not sure you'd come away with any more space, just a different configuration.  Do you have the opportunity and the funds for the 23?  Or, are you like me and have money trees that have withered in the drought?   I have had fun and learned a lot working on our little 16.  For me, that's all part of it!  Of course, sailing is the ultimate goal, now isn't it?

Having said all that, if you pursue this, please keep us informed with your progress.

[Lost Lake]

Even with the post out you won't have room for that pool table...

[tsaiapex]

I was the one posted CP19 compression post bent bolt.  I exchanged email with Jerry Hutchin as to why doesn't the post sat on the keel.  His said it was easier during the production because the compression post may not be exactly the same length from one boat to another.

I replaced the bent bolt with larger one and I am sure it will be fine for another 20 years.

Your modification idea sounds like major work.  You should email Hutchins to see what they say.

[mayrel]

Thanks all for the candid and honest responses; this is what makes these websites so important.  I'm not an engineer, so I wanted to pose this question to owners'.  My question was partially driven by wanting to eliminate the inconvenience of the compression post; at 6'1" I need all the "elbow room" I can get.  I was also driven by the idea that it might be possible to strengthen the function of the compression post by replacing it with an appropriate SS compression brace of some sort.  Based on your responses, I think it possible if this brace would transfer the weight/stress from the rigging to the keel of the boat.  From what I can understand, my idea wouldn't work effectively, and there wouldn't be an appreciable gain in "elbow room".  But it never hurts to explore these crazy ideas; sometimes you hit on something that might work.  So, I think we'll concentrate on the Compac 23.  We're anxious to locate one near us and hopefully get a chance to go aboard to see for ourselves if the 23 will suit our needs.  Again thanks for the responses....

[Craig Weis]

Looking at this proposal...don't do it.

A arch fabricated to replace the compression post would need to be rather high, vertically speaking, maybe as much as 4" in the truss height. And to carry the load to the hull's port and starboard side moves the moment of bend and moment of torque not vertically but horizontally. The deck/hull joint would carry the load and she was never intended to do that. Additionally the arch would need to be installed 'bare hull' without the deck and cabin installed. Let me think about this some more.

I thought about doing something like this for the sole of the cockpit by removing that foam block from under neath, opening up some storage space. When I ran this idea past Rich Hutchins at the All Sail Boat Show in Chicago he said that I would need to carry [read spread the weight out] the whole load of a couple of people standing on the fiberglass sole of the cockpit. That is what the foam block does. It ain't for flotation. That's my two cents. skip.