Side deck recore from below

[Jason K]

Before I painted the decks, I had the ubiquitous few soft spots. Instead of doing the job right and recoring, I elected to utilize the drill and fill method. That is, as I've pointed out before, more of a band aid than a repair.

Last week when we went on a little evening cruise, one of the guests jumped onto the side deck pretty hard. I was below and I heard a crack. I think it may have been some of the filler epoxy that cracked under the stress. Anyway, the deck was, I thought, weaker and I found a void by tapping on the deck. I drilled a hole and found wet core. Rats. Some Band Aid, right?

Anyway, I am going to recore the sidedeck. I've recently painted the top, so I am going to go at it from underneath. Test drilling done today seems to suggest wet core from the aft end of the cabin top to just about the middle of the forward deadlight on the port side. Here's the preliminary gameplan - any suggestions?:

1. Cut away the bottom skin and try to keep it in one piece.

2. Remove old core and grind away the epoxy mess from the drilling and filling.

3. Cover the end-grain balsa with unthickened epoxy to seal.

4. Set balsa in place with epoxy thickened with colloidal silica. Use jacks and a 2X4 to hold core while it sets to upper skin.

5. Fill what void remains on the edges with thicked epoxy.

6. Repair/reinforce bottom skin with biax.

7. Reattach bottom skin with epoxy thickened with colloidal silica.

8. Apply a layer or two of new cloth to smooth out repair.

9. Fair and paint.


Advice anyone?

[Tim]

Everything you suggest will work fine. Everything is complicated by working over your head, of course, but otherwise the job is straightforward.

You will probably find the bottom skin is extremely thin, and probably resin-starved. You may not have good luck saving it, but see what you can do. It'd be just as easy to use new material instead of the old bottom skin, unless you find that yours is thicker and more substantial than the typical Triton bottom skin.

Mine was about 2 layers of light cloth--that's it. I stuck a putty knife right through it while cleaning off old core from above.

[Jason K]

That was a quick answer - thanks, Tim.

My reasoning for trying to save the lower skin was to utilize it for creating a reinforced bottom skin by wrapping it in biax. Once the new skin had cured I was simply going to press it into place and bond it with thickened epoxy in the same way I plan to attach the core. My thinking is that will be easier than laying cloth overhead. Sound reasonable?

What tool would be the best for removing the bottom skin? There's not much room over the shelf above the settee, as you all know, and I need something that will cut just through the bottom skin with precision.

Also, and I know I'm shooting myself in the foot here, but this job doesn't sound all that bad. Am I missing something or is it really this straightforward?

[dasein668]

but this job doesn't sound all that bad. Am I missing something or is it really this straightforward?

I'll be interested to know how you feel about this after you start glassing over your head! Other than that... no, I think it should be pretty straightforward. Wear something to cover your hair, though!

[Rachel]

I recored the foredeck, parts of both sidedecks, and a bit of the cockpit floor from below on my Montgomery 17, because the decks were prisitine and original - had never even been painted.

It was a pain, to be sure, but sometimes it's the way to go. I didn't re-use the skins because I pretty much destroyed them in the removal process; instead I just put new cloth on and faired the area. On that boat, the underside of the sidedecks was low enough that you weren't really prone to staring at it, but it came out quite nice nonetheless; so, if you have any trouble at all getting your inner skins off in one piece (and I'm thinking they are going to break because of being attached to those repair plugs), I would just give in and make them of new glass.

I cut the inner skins off with a Fein Multimaster that a friend loaned me. Dust-in-the-face was an issue (although I did wear a respirator and goggles), so I taped a length of 1 x 1 scrap to the end of the vacuum hose, which made it easy to hold up next to the tool (I suppose these days you might have a vacuum hose attached right to whatever tool you end up using).

I held the wet glass (thin layers) up with blue tape while it was curing.

One other trick I found handy was when I was filling deck hardware holes with thickened epoxy prior to re-drilling as I finished up the job. Instead of masking tape, I used clear packing tape to cover the underside of the holes. It worked great and enabled me to visually check that I was getting the hole completely filled. Some were a bit stubborn about filling up because of trapped air, so on those I just injected the thickened epoxy from the underside. I used some syringes I got from my vet (with needle), filled them with the epoxy mixture, and poked them right through the tape. When the hole was full (of course I taped off the deck around the hole with blue tape) I withdrew the syringe and then quickly slapped another piece of clear tape over the first one. Kind of like how you fill the lower unit of an outboard with oil from the lower hole :-)

I know Charlie J (and his wife Laura) recored parts of Tehani's sidedecks from below, so he may chime in as well.

[Rachel]

Oh, I should say a bit more about the MultiMaster. I didn't try anything else, so I can't really compare, but I can say the MM was very precise and easy to control, not too heavy to hold overhead, didn't make all that much dust (considering), and has the added advantage that it won't cut skin if you slip (it's apparently related to those cast-cutting saws that won't cut skin because of the way they oscillate).

--- Rachel

[bhartley]

Jason,

I had a spare sheet of 12" x 12" HDPE purchased for another repair which has come in extremely handy while recoring my Typhoon. Epoxy won't stick to HDPE and it is rigid enough to make a firm, flat surface. It comes in various thicknesses. (My piece is 1/8" thick and was <$3.00 from McMaster-Carr). I put a piece of luan plywood on top of it for bracing when needed.

I'm forever mixing up just a bit more resin than I need and mixing it in quart milk jugs makes it easy to pop out the hardened resin and reuse the container too.

Cheers,

Bly

[Figment]

I'll second the suggestion for the multimaster. A cutting wheel on a dremel could work as well, but this really is just the thing the multimaster is made for.

[Tim]

One of those Roto-Zip tools might work too, depending on the clearance. The bits tend to break quickly, though.

Recoring isn't rocket science. It's messy, but the actual process isn't difficult. The worst part for most people is making those initial cuts into their boat; I think getting psyched out about this is one reason so many people dread the recore.

Recoring from below, you also save the need to laboriously fair the decks. This is another one of the less fun parts of the general recore process, and also one of the more difficult (to do well).

Laying cloth overhead isn't that hard if the pieces are small enough. Large pieces are impossible, but sidedeck-sized pieces a couple feet long are totally do-able. Yes, it will drape all over your arms and hands and it will be messy, but once you get it started with the roller it sticks at once, and the worst is over.

If you can save the bottom skin, then your plan sounds good. I just wanted to warn you as to the potential for the lower skin to be a total throwaway.

Good luck! We expect a full report with pictures please!

[CharlieJ]

I'm betting that old under deck won't be salvagable. Like Tim said, mine on my Meridian was a single layer, in my case of roving.

I cut the skin using a dremel fitted with the attachment that makes it sorta like a rotozip. Used a carbide blade and set it to JUST cut through the skin. Broke one blade, then figured out how to use it and did the rest with a single blade.

I recored mine with long strips of 12 mm Okume set in epoxy. I held it in place using thin sticks from the settee tops up to the underdeck, long enough to slightly bend the sticks. Then filled the remaining gaps with thickened epoxy and laid on three layers of glass, with extra at both edges cut into about 4 or 5 inch wide strips.

If you pre cut the glass and roll it up it's not hard (once you get the hang of it :)) wet out the surface, thenstart the glass at one end and roll it in place unrolling the bundle as you go. It's a lot easier with two people, but it can be done singlehand once you figure it out

It was a WHOLE lot easier than glassing the underwings of the 35 foot tri I built, using 48 inch wide cloth, 22 feet long *grin* THAT job took three people to do.

I have pictures if you'd like to see them

[Jason K]

Thanks all! I'm going to give it a go this weekend, if the weather is remotely accomodating. I've already ordered the balsa and I have more epoxy than you say grace over. I just need to order the fiberglass.

Good luck! We expect a full report with pictures please!

No problem with the photos. My new digital camera already has paint on it, this will be a great opportunity to add some epoxy.

The worst part for most people is making those initial cuts into their boat

I got over that a long time ago. I always enjoy the bewildered looks of the dock walkers as I'm cheerily drilling a hole into my deck or doing some such seemingly destructive activity. (One time a lady on a Bayliner type powerboat in the guest slip next to me said, "I've seen some fixer-uppers before, but that.... This was when I was fairing the decks and they, admittedly, looked pretty bad. I was pleased when they crashed into the dock at about 5 knots when they returned)

I'm betting that old under deck won't be salvagable.

I'm afraid you're right, but I'll give it a shot. From your and Tim's description, it doesn't sound like that's the end of the world. I'm also not too concerned about making a mess as I was planning on repainting the interior this weekend and will be doing so in the near future anyway.

I would love to see those photos, if you don't mind. My email is [email protected].

[Rachel]

Thanks all! I'm going to give it a go this weekend, if the weather is remotely accomodating.... ... I'm also not too concerned about making a mess as I was planning on repainting the interior this weekend...

Gee, maybe I'm making too much of this project boat thing -- now I see it's just a matter of a couple of free weekends ;-)

All kidding aside, Jason, it's cool that you're just jumping in and getting it done, AND going out sailing besides!

... I was pleased when they crashed into the dock at about 5 knots when they returned

Har har! (Oops, did I say that?) I'm sure you were running to help them with the docklines and *just* didn't make it, by mere seconds....

[Jason K]

Gee, maybe I'm making too much of this project boat thing -- now I see it's just a matter of a couple of free weekends ;-)

Yeah, what's the big deal? :)

Believe me, I still have a long way to go.

Har har! (Oops, did I say that?) I'm sure you were running to help them with the docklines and *just* didn't make it, by mere seconds....

Uh, yeah, oops. The guy was pretty embarassed so, trying to be polite, I said that those boats could be hard to dock when they only have one engine. He replied, "Oh, it has twin engines."

[Ric in Richmond]

This may give you the reason you always wanted to shave your head....

Definitely invest in total body coverage. You will get it everywhere.

I want pictures!!! I need to do the same thing around the gate on my Alberg 35.

Have fun, good luck.

Ric

[Curmudgeon]

so I am going to go at it from underneath

Ahhhh, so I'm not alone in recoring from the inside., and how glad I am to have YOU try it first. My plan is similar except that I decided to vacuum-bag everything. There's an extra expense involved but I'll be recovering all my bulkheads and floors with 1/12" teak veneer and couldn't see getting a satisfactory result any other way. For the size of repair you have though, vacuum-bagging probably isn't worth it.

[Jason K]

Well, I'll certainly keep you in the loop. It's so much nicer learning from other people's mistakes, rather than your own.

As it stands, I'm just waiting for parts. I've ordered the core and more fiberglass (biax and 10 oz cloth) than I'll need. I have 2 gallons of epoxy on board already with plenty of silica and fairing compounds. I'm really eager to get the project underway.

With luck, I'll be able to start on Saturday. The weather calls for showers but I might get lucky. Worst scase scenario is I'll start cutting holes in the boat on Sunday. Fortunately, Mardi Gras is this week. Nobody goes to the office during Mardi Gras, so I'll have the days for the boat and the evening for...well, let's just say I'll live up to my avatar.

[Dan H]

No doubt this is totally wrong, but the few times I did fiberglass overhead, I layed the glass on 5 mil plastic and wet it out there. Then I carried the plastic and glass into the boat and put it on the overhead. I rolled the air out working from the center with my little fiberglass roller and then slowly pulled the plastic off. I rolled the plastic into a little tube and kept rolling the fiberglass as I went. Worked for me.

[kendall]

No doubt this is totally wrong, but the few times I did fiberglass overhead, I layed the glass on 5 mil plastic and wet it out there. Then I carried the plastic and glass into the boat and put it on the overhead. I rolled the air out working from the center with my little fiberglass roller and then slowly pulled the plastic off. I rolled the plastic into a little tube and kept rolling the fiberglass as I went. Worked for me.

I've done it with dry cloth, but used some of those 'T' headed straight pins (snagged from my grandmother's sewing box) to hold it in place, they hold well and are easy enough to get a grip on for adjustments and removal when finished.
also used steel strips to spring in on some areas, the narrow stainless steel rulers and yard sticks work good.

ken.

[Jason K]

Uhhh...How do you get thickened epoxy out of your hair?

Actually the project is coming along pretty well. The combination of a big boat project and Mardi Gras may do me in though.

A couple of preliminary observations:

1. This has to be harder than doing it from the top.
2. Do not underestimate your epoxy or sundry consumption. This isn't the type of job that accomodates a mandatory break.
3. Keep the fiberglass manageable - too large a sheet will pull itself down with its own weight - even if the surface is tacky.
4. Precut everything for every step you plan to do for the day.
5. Think out your braces. The core material need to be pressed firmly into place. This is particularly the case if you are using end-grain balsa cut into kerfs. Even with the scrim, it will want to pull away in spots.

The braces are the one major step I didn't properly plan out. I thought the braces I fabricated would be adequate. They weren't and I was frantically cutting apart storm debris with a circular saw to make more. Other than that, no problems so far. Will update this in a few days with photos when the project wraps up.

[Jason K]

___

[dasein668]

Uhhh...How do you get thickened epoxy out of your hair?

Scissors.

I think this falls under "I told you so!" hehe.

I had this problem when glassing my icebox... head down inside an enclosed space full of wet-out glass... ugh. It gives me the willies just thinking about it!

[Figment]

aaah, memories of the bulkhead replacement job! I was still picking out epoxy bits two haircuts later.

[Figment]

How's it going?

[Jason K]

Sorry, I should have updated this thread by now, but I epoxied myself to the cabin top.

The side deck is hard as a rock, so the operation has certainly been a structural success. I have two layers of biax and two layers of 6 oz cloth as the bottom skin right now. I am still finishing the area out and the next step is to fair the existing glass work. I may end up laying another layer or two of 6 oz cloth for added strength, then final fairing and paint.

Left the camera on the boat, but I have photos and will post them ASAP.

[Jason K]

I thought I'd update this.

The project is taking considerably longer due to non-boat stuff.

However, there is slow progress and only final glass work remains. The photos below are from earlier in the project. I still need to update the photos of the glass work.


There was enough moisture in the core that I could wring it out like a sponge.


This is some of the glass that was attached to the old core. Looks a wee bit resin starved.


From early in the core removal process. You can see a number of the epoxy plugs from the failed "drill and fill" repair attempt.


The damaged core extended farther than I originally thought. (Doesn't it always?)


I went well into good core to be sure of eliminating all of that area's rot


This is the area cleaned and ready to accept fresh core. The gap between the skins was filled with very thick epoxy.


The core for the project was cut and dry-fit.


The core was pressed and braced into place. It took much more bracing than I had planned for. I placed fresh glass under the upper skin to add a little bit of strength and ensure a good bond. I covered the top of the core with thickened epoxy and braced it into place.

The small gaps were filled with thickened epoxy before the bottom skin reconstruction began.

[grampianman]

Jason,
I'm quite impressed with your under-deck recore. I took the coward's way out and did it from on top. The deck layer was already a mess from the P.O.'s neglect and the stanchions had been allowed to punch through the rotten balsa and so it wasn't a major decision to go from the top.

I did find I still needed to brace the underside as I needed a lot of weight to make the plywood conform to the shape of the deck/cabin-top.

Again, great job. My fore-arms are itching at the thought of all the grinding you did to get the area smooth enough to re-epoxy!

Cheers,
Ian