Tabernacle / bulkhead failures & fixes . .

Welcome to PocketShip.net! This bulletin board is for builders of the Chesapeake Light Craft-John C. Harris "PocketShip" design, a 15-foot micro cruiser sailboat built from a kit or plans.

For more information on PocketShip, click here: http://www.clcboats.com/pocketship

This site gathers PocketShip builders in one place. Here you can share photos, tips, questions, and---eventually---your sailing adventures in PocketShip! CLC will also post design updates and tips here as they come up.

We'll try to knock down spam as quickly as possible.

Moderator: John C. Harris

Forum rules
Spam or commercial posts will be deleted.
This is a civil forum: no flames or drunken tirades.
Please stay on-topic.
PocketShip's Web Page: http://www.clcboats.com/pocketship
If you need CLC customer service: http://www.clcboats.com/forms/contact_us.html
We'll try to delete spam as soon as it appears.

Re: Tabernacle / bulkhead failures & fixes . .

Postby craig on Tue Jul 30, 2019 3:43 pm

John,

My plans (purchased in 2014) still indicated 3/4" material for the tabernacle. You may have already changed them in future revisions, but just in case, wanted to give feedback.

My tabernacle is made of 3/4" hard southern yellow pine and it's never budged.

- Craig
Titania, launched January 2015
craig
 
Posts: 253
Joined: Fri Feb 21, 2014 1:04 pm
Location: Chapel Hill, NC

Re: Tabernacle / bulkhead failures & fixes . .

Postby mark48 on Sun Aug 18, 2019 7:28 pm

Hi all,

I'm following up on my July 29 post which contained a photograph of a split in my tabernacle (on page 3 of this thread). This entry details my ultimate fix.

First, my thanks to the PF Forum participants who weighed in with advice and thoughts, and particular thanks to John Harris. (I could only dream of an enhanced rig with spinnaker....)

My repair: I removed my tabernacle (thankfully I could do so). The split or crack in the wood tracked down and angled such that the inner end seemed to terminate where the side was glued (and screwed) to the tabernacle back. On the outer face of the tabernacle's side however, the split seemed to extend further down. Identifying the terminus of the crack was very difficult however, even when prying it open a bit.

Ultimately, I drilled 1/8" holes at the tabernacle side's top, down along the crack, and at the junction of the tabernacle side and the tabernacle back. (You can see this hole in the second photo just below the surface of the mast, tucked into interior starboard upper corner of the tabernacle's sleeve. I also drilled a 1/8" hole where I thought the terminus of the crack was on the outboard side of the tabernacle. (Woodworking people tell me that drilling a "stopper" hole to arrest crack propagation works in plastic but not in wood, but there seems a difference of opinion on the 'net so I drilled one there.)

I then pushed in un-thickened epoxy using a syringe and 18ga needle (very tough pushing), a syringe without a needle, a length of small dowel to "plunge" liquid epoxy down the holes, all assisted with a vacuum hose sucking on more distal crack openings. When I seemed unable to get more un-thickened epoxy in, I added thickened epoxy to fill the drilled holes and clamped along the entire crack length overnight.

Then, because I don't have complete faith in my glue job given the length of the crack and the difficulty getting epoxy into its entire length, I contracted with a local custom metal-working shop to fashion a bracket of 1/8" aluminum which surrounds the upper ~12" (or so) of the tabernacle as shown in the accompanying photos. I realize this is significantly more bracket than JH installed on PS#1.

The front of my bracket wraps around the forward faces of the tabernacle's sides; it is also one piece (wrapping entirely around the aft face of the tabernacle) so that once the bracket is slid down over the wooden structure (like a sleeve) and the mast pivot bolt is threaded through, no screws are required to fasten the bracket to the tabernacle. This avoids the issue of putting more screws into the wooden tabernacle, possibly weakening the wood (and providing portals for water entry). I realize this is almost certainly more bracket than necessary, but now I'll worry less. It is also more weight up high and to counter this I will add 10# more lead ballast under the mast.

In the future, I'll be especially careful to keep the mast aligned strictly fore-and-aft when raising and lowering it. But I think my tabernacle is now repaired. All that's left is to re-rig the boat and make sure my shrouds are TIGHT.

All the best to all CLC staff and builders, and particularly PS Forum users,
Mark
Attachments
Tabernacle.d.jpg
Tabernacle.d.jpg (114.81 KiB) Viewed 158 times
Tabernacle.b.jpg
Tabernacle.b.jpg (84.41 KiB) Viewed 157 times
Taberacle.a.jpg
Taberacle.a.jpg (75.65 KiB) Viewed 157 times
mark48
 
Posts: 123
Joined: Fri Jun 28, 2013 9:55 pm

Re: Tabernacle / bulkhead failures & fixes . .

Postby Shudoman on Mon Aug 19, 2019 9:55 am

Wow Mark,
That's a nice job that they did for you.

When I built my tabernacle I was also worried about it cracking (I made mine out of 1" white oak). After I cut the tabernacle I epoxy laminated the outboard sides with some scrap 1/4" marine plywood. It's probably not nearly as split resistant as yours but it allows me to sleep at night.

Regards,
Bill
Shudoman
 
Posts: 139
Joined: Sun Feb 15, 2009 10:31 pm

Re: Tabernacle / bulkhead failures & fixes . .

Postby mark48 on Mon Aug 19, 2019 10:54 am

Thanks Bill,

Sleeping well at night cannot be over-rated.

:-)
Mark
mark48
 
Posts: 123
Joined: Fri Jun 28, 2013 9:55 pm

Re: Tabernacle / bulkhead failures & fixes . .

Postby riverron on Mon Aug 19, 2019 7:21 pm

Very nicely done Mark!
riverron
 
Posts: 208
Joined: Fri Aug 07, 2015 10:29 am
Location: Richmond Virginia

Re: Tabernacle / bulkhead failures & fixes . .

Postby John C. Harris on Thu Aug 22, 2019 8:31 am

That looks really shipshape, Mark.
John C. Harris
 
Posts: 182
Joined: Thu Feb 05, 2009 12:39 pm

Previous

Return to PocketShip Forum

Who is online

Users browsing this forum: No registered users and 4 guests

cron