Com Pac 19 Bulkhead support for Compression Post Cracked.

[skip1930]

       Com Pac 19 Bulkhead Support for Compression Post Cracked.

So I took a look~see the other day into the vee birth area at this bulkhead from the backside. [I was noising around for some things in storage]
I saw where the compression post was bolted onto the 1/2" [?] plywood bulkhead.

We have the bottom of the post about 5" above the hull.
Two bolts about 4" apart with nuts and washers poking through the bulkhead and post about 10" above the bottom of the hull.
About 3" below the bottom bolt is a crack running with the grain, port and starboard, for maybe 24 to 28 inches.
The crack is just a crack, it is not pulled open or apart.
When I'm sailing I hear things creaking, I feel the 'creek' in the post when sailing with the tiller lock engaged giving me time to go below to investigate.

-->I'm thinking maybe I should bolt in a second pair of bolts, like the top pair of bolts, below the crack to stabilize this bulkhead using the post to do this [so the crack will be sandwitched 'tween the two pair of bolts] and of course prize open the crack a little bit to squirt in some two part epoxy with a large diameter hypodermic needle.<--

I'm soliciting your un solicited opinions sailors....what say you?

Thanx skip. I added this 16" x 16" hatch for storage.

[MacGyver]

Skip,

When I was in school for West System Epoxy we had a test (to show how awesome the epoxy is) and it involved taking a regular piece of 2x4 pine and seeing how much it took to pull it apart under load.

The grain took around 250 to 300 lbs of force before she split.

Our objective was to take West System and use it in a fashion to make the blocks stronger. Our block survived 5,200 lbs of load.

Why did I say that to you......... well, wood in its aging will dry, and possibly that is why it is doing it, or maybe sailing in your conditions, but either way, use some west system to repair that post. You wont need to add anymore holes, etc.

I will write back in here a process I would do after work today since I am on my way out the door now.

One note, No epoxy is like West System, I have used a ton of different epoxies, and there is only 1 other I would recommend for this job.

I will post again later with the repair details.

Mac

[wes]

Skip - I have had concerns about the same spot. I think it's a (rare) design flaw of the 19 that the compression post bears on such a thin piece of plywood. I had no cracks, but I could see that those bolts were being forced downward; one was bent.

My solution was to cut a short hardwood post and slip it under the bottom of the compression post. I slacked the rigging, then drove in a couple of wedges between the posts to lift the bolt holes back up to their original alignment. Then replaced the bolts with Grade 8, glued the wedges in place and tightened the rigging. The effect is to transfer the downward force of the mast all the way to the hull/keel rather than to the plywood bulkhead.

So far, so good - seems to be a solid fix.

Wes

[Keith]

Something else to look out for...

When I first sailed my boat in '98, I noticed cracks on the deck at the forward corners where the cabin meets the deck, both port and starboard.  Turns out the compression post had split at the bolt holes and dropped, putting the weight of the rig and crew directly on the now unsupported cabin roof.  I replaced the compression post and, to prevent the possibility of it splitting again, added a single 1/4 inch bolt through the post perpendicular to the mounting bolts.  Was also fun repairing the fiberglass damage from below (to minimize damage to the non-skid pattern on deck).

Cheers,

Keith 

[skip1930]

Thanks guys.

Kieth: The post itself and bolts a perfect. Everything is square.

Macgyver: The wood may have dried out and opened up a bit. I'll buy that. Roilling on a layer of West System sounds swell. That will soak into the crack and sourrounding wood. Spreading out the weight over a larger surface...we used West System in our boat building class.

Wes: Setting the post on a doubler glued to the plywood is a good idea as well. It's all about transferring the weight/force. Spreading out the weight over a larger surface...

Keep talking. Who thinks we have a structural failure of the bulkhead? Any ideas on why this happened? What was stressed? Did some thing unmovable move? Any off the wall ideas are better than none. Raise your mouse. The hull did not pull apart.

May be a picture or two might help. That means I have to crawl back down there again...oh well.

p.s. the hatch fits perfect. Nothing moved on the vee birth deck.

Thanks again. skip.

[skip1930]

OK here is what happened. It was me who caused this crack in that 1/4" [not 1/2"] bulkhead. Yep with brute force I slammed a Coleman Cooler, that was just a bit squeaky tight because of the molded handles on the cooler, into that space between the two quarter births and once in that cooler wedged nice and tight. I was a little too aggressive getting the darn thing out. Rest assured sailors your Com-Pac 19 is not prone to horizontal cracks, not unless I'm on board. Don't I feel stupid. I ground the handles off the cooler handles by a 1/4" each side and all is well.

skip.

[Tim Gardner]

Skip,

I like your added flotation under the bow.

TG

[skip1930]

Like that added 'flotation' under the bow wow wow is going to help if she fills with water...but it sure cleans up the inside of zzzz boat!
And I got it if I need it for added guests. Like a dock box on board.

skip.

[Koinonia]

That crack is way below where the post even bolts to the wood, Ive actually wondered about a crossbar to take the mast compression that matches the contour of the cabin.  Ive seen this on a boat with thin laminated teak, worked great and looked great but since I dont have a 19 around to look at I cant really say if id deffinatly do that or not.  Just an idea to get the post out of the v berth area.