Re coring a foredeck questions

Badlatitude

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I looked at a single inboard boat today for VERY short money. Solid glass hull but a cored topside. the fore deck is solid as a rock but from inside the cabin the end of the core is visible and rotten. I propose to cut the glass on the ceiling of the cabin and remove the nasty balsa. Leaving the outer glass foredeck in place.

Would a product like divinycell be correct to use in the re coring or the foredeck from inside the cabin?
 

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Sure, you could use balsa core too - either way is going to be sloppy and messy (don't wear your good clothes, just saying)

Gravity will be against you for this application. I would suggest using a bedding compound like probond or the like (probond mixes with MEKP like normal resin, a product like corebond uses a bpo paste). Trowel on your product for the area, wet out your core material, position and put into place with a heavy roller or thick bubble buster to remove voids and adhere the core in nice and solid. Work in small batches and keep your area manageable. Any product that makes its way up through seams can quickly and easily be knocked down with your wet roller that you've been using to wet out your core material. Hot coat your core when you're done and it wont drag the resin out of your fiberglass when you cover the core up.

Until they perfect a gravity switch you will most likely encounter a few drips now and then.
 

Badlatitude

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It can be done ....but not easy..working upside down..MESSY


Yeah id imagine so lol but it would be the easiest way to resolve the issue ( mind you you can jump on the foredeck and its not soft) but from inside you can tell its F'd. Almost 100% it was caused by whom ever put the tower on her. It appears the bases are directly bolted to the deck and gunnels with no sign of 5200, caulk or any form of sealant.... Let alone a backing plate. We are talking about a 5k 25 Dusky single gas inboard that runs like a top and will be a beater fish boat. The "cuddy cabin" will be used for storage at best.

Love the beater, love the price.... hate the rotten core on the foredeck. Its the only place it shows any sign of an issue. The stringers, tanks and everything else is super solid ( aside from the cheap ass plastic inspection hatches) The foredecks core is the only glaring issue.
 

Badlatitude

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First team would mixing up a batch of resin with something like west systems 404 accomplish the task of "glueing" the core to the underside of the deck?
 

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Ehhhh...

I wouldn't do that, or advise doing that

I'd build up solid glass before I did that. Heck I'd cut strips out of quarter inch plywood and put them in place with liquid nail before I did that.

Probond is made for this type of work, while your "adhesive" idea might suffice - where safety is concerned I would err on the side of not having any issues down the road. It may be a beater fishing boat to you, but it might be the next guys dream boat.

Safety is no accident.
 

steveinak

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might be talking thru my arse here but how about drying the core, if thats possible, and injecting something like gitrot or a thinned resin to soak up into the core??? might save a lot of upside down cussing.
 

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Hard to do. Removing the moisture from the core and then trying to re-impregnate those open cells, which have most likely already ruptured, would be an ordeal beyond that which mortal men could do. If it was a small area with open channels, sure, it could be done (with some awesome equipment to draw a vacuum through the piece and displace the voids with resin) but an entire top?

Much easier to take a cut off wheel, nob out the interior skin, remove the core, prep the area, bed new core in and seal it up.

One might considering applying baby oil to their arms so that any stray resin that decided to leap could just be left alone to kick and then pop off.
 

steveinak

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Travis,
could a cored panel be layed up first and then somehow be "glued" up to the foredeck?? that would avoid a lot of the resin raining down on ya ?? I would think it would be hard to get any resin into the core hanging upsidedown?? am i making any sense or am i kinda dreaming here? We've had 3 beautiful days in a row here so maybe i'm a bit balmy from too much sun!!
 

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Not really, you would need backing plates and stands to do it. Aside from the git-rot idea, this one is by far the most difficult.

I think you're over-thinking the situation some, this really isn't a big deal.

All you need to do is remove the affected area, just a little cut off wheel would do the trick so nice it's almost sad.

images


Surface prep the bottom side of the laminate, trowel on some product, have your core strips ready, I would suggest nothing really wider than 8 inches (6 would be ideal). Now you could do this one of two ways, if you think you are up to it, strip the core sheets lengthwise, now you have a four foot strip that's ready to play. Toss a rubbermaid (or some other brand) plastic trashcan down where you will be working - making sure it is on its side, prop up some shims so it doesn't roll around on you, and now you have the perfect table to wet out your core material. Scrim side down the core will open up all of its kerfs so that you can coat everything with resin (probably the reason the condition of the old core is so bad, proper resin penetration didn't occur). Now that you have a nice soggy mess, pick it up with your double (or triple) gloved hands and starting at the end with your non-dominant hand holding the core, slide your dominant one along the length to bed the strip into the compound on the top, having your hand nice and flat and don't be afraid to push (if you want to do that breathing your wife learned how to do, go ahead. no judging here). It might take you a little bit to learn how much resin is too much resin (damned gravity) and how much is just right, it's easy to reclaim excess resin from your strip just by putting down a plastic paint tray (or one with a liner, or even both - just watch out for exotherming - know enough when to step away from the project and let it kick. Better to do a little grinding than get into a serious problem.)

Once your strip is in place, go over it with a stout bubble buster or some other instrument.

BBNEW.jpg


a laminate roller might work for this job as well, you can really put some pressure behind it if need be.

820909520153lg.jpg


But remember, you're only displacing the bedding material and making it one with the resin infused core, you want to get the bedding material up into the kerfs as much as possible without destroying that connection. A nice even pressure does the best job, you don't have to try to kill it.

Now that you have your first strip in place grab another and repeat the process. It will take a little bit to get the pace down but it's really simple once things are going. Trowel an area for two and a half strips, put them in place all the way across, do another area with the trowel, more strips, trowel, strip, etc etc. Mix up small batches, that way you can walk away whenever you feel like it (your back will let you know when that is, trust me). No doubt you will get some bedding compound to peek up between your strips or even the kerfs themselves - this is easy to fix. You could say "fahgettaboutit" and just touch them up with a grinder when you prep the area for the interior fiberglass. You could swipe your finger along the seams (using the back of your finger like a squeegee). Or you could just take your roller and roll them over and hot coat the back side of your core at the same time (that's what I would do).

Be sure to stagger your joints on the strips, easy enough to do, just cut the skrim and make your strips shorter/longer. Don't worry about little voids on the corners of your curved radius on the trunk top, cabin, wherever you're coring. A little bedding compound as a filler after you are all done is the simple easy way to solve this, pound it right in there. Pretend it owes you money and you're here to collect.

This is a big daunting project that is hella easy if you just take a step back and consider things for a few moments. Having a pair of helping hands would be fantastic, be that a small child, an understanding wife, or even a parent figure who is willing to help out. They can mix product and apply resin to your strips as you're fighting the gravity of the situation.

Remember:

  • Small batches are your friend
  • Always have a backup set of tools (gloves, roller covers, anger management classes, etc)
  • Know when to walk away, take a step back, remember to breathe (hee hee hee - hooooo)
  • Wear your safety gear (glasses - most important, probably a hat, some old clothes that you don't care about, gloves - glorious gloves and multiple layers won't hurt you one bit, you can shuck them off and keep going to slap a new pair on much easier than you would with sweaty fingers)
  • Proper ventilation (those big 20" square fans work wonders, pump that stuff outta there)
  • Have fun. If you can't have fun doing this project then you are doing it wrong.
Easy Peasy
 

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And what to do about the deck you're working from and other areas that are in the drip zone? Forget about drop cloths and plastic sheeting (seriously? are we trying to get hurt? plastic sheeting is slippery on a GOOD day when you're not working overhead with basically lubricant until it starts to cure).

Save yourself a lot of grief and get a (few) bag(s) of floor dry

CLAYGRANULAR.jpg


A little cleanup later on will be much better than falling and breaking something (like your elbow). Just toss down a nice thick layer and even the biggest globs of slop flying off your roller will be subdued before they find anything else to attach to. Kitty litter would work too, but I don't think you would get as much product for the price as you would with the oil absorbant. I would advise against the fine powder type and go with the coarse type, better grip for your feet.

I use Oil-Dri in the shop, it's fantastic.
 

Badlatitude

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Yeah the core is definatly past maybe it will dry out.

WOW that is some how to article First Team! Luckily I have no shortage of tools and such. I still havent decided if im going to pull the trigger on the dusky yet. If I do Ill try and remember to take pics etc. Unlike my skiff project that I took about 4 pics in a month lol
 

Badlatitude

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Im really glad you came into the thread. Ive built some skiffs and fixed, glassed, repowered, wired etc. But never tried to do a core from underneath. You have definatly enlightened me to several things I had not thought about. Like bonding the core to the underside of the deck with a bonding adhesive. I would have tried to do that with resin and most likely make a hell of a mess!

I will most likely pick this old gal up as I hate to see things in disrepair and it would make a good western sound beater for a while untill Laura and I decide how big we want to go. Comming from a 35ft commercial boat. She wants max comfort and I want blood and guts. Plus we have to factor in accessability for family with medical issues. So the battle continues!

F/V What is your opinion on a hull side door. Like a transom door but wide enough to fit a travel wheel chair through? A 25 Dusky is a streched 23 with solid glass hull and gunnel caps.The only core is in the decks
 

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F/V What is your opinion on a hull side door. Like a transom door but wide enough to fit a travel wheel chair through? A 25 Dusky is a streched 23 with solid glass hull and gunnel caps.The only core is in the decks

those are easy, been thinking up some stuff on this in my spare time, probably toss up a photo of what im thinking of later tonight when i get home.

you just might get a kick out of it :)
 

Badlatitude

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Very cool. I look foward to it!

How do you feel about foam or scored divinicell for core? I figured it might be easier to do slightly larger areas with it than multiple strips. As far as helpers I have a goy almost full time plus lots of friends that can lend a hand. I personally prefer to mix my resin myself so I can only blame myself lol
 
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F/V First Team

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Very cool. I look foward to it!

How do you feel about foam or scored divinicell for core? I figured it might be easier to do slightly larger areas with it than multiple strips. As far as helpers I have a goy almost full time plus lots of friends that can lend a hand. I personally prefer to mix my resin myself so I can only blame myself lol

it is still square area that you are doing overhead. a long narrow strip can be manipulated and supported better than a short and wide one.

you can only get so many elbows in one space at a given time, i would still suggest strips
 

Dfrenzy

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Im not sure if this will help or not im sure i dont have the experience working with glass that many on here do. Last spring i did some overhead glass work in the cabin of my boat. I used a board slightly larger than the piece i was putting up. I covered the board with foam and then covered the foam with plastic. I then put my glass work ontop of my board covered in plastic and foam and sandwiched it into place using those truck bed cargo bars to press it into position. The plastic will just peal from the glass when dried. The purpose of the foam was to distribute pressure throughout the entire board. This worked out great for myself.
 
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