Soft Deck (small area) Repair

This forum is for comments and the exchange of information relating to Trojan Boats and boating. Please do not post used parts or boats For Sale in this area. For general, non-boating topics please use our "General Discussions" section.

Note: Negative or inflammatory postings will not be tolerated.

Moderators: BeaconMarineBob, Moderator, BeaconMarineDon

User avatar
Paul
Active User
Posts: 1141
Joined: Fri Jun 10, 2005 1:02 pm
Location: Windsor Ont.

Soft Deck (small area) Repair

Post by Paul » Sun Jan 10, 2016 10:27 pm

It was such a nice day Saturday, I decided to head down to the boat to get a start on a spring project. The deck has one soft spot directly below the rear of the port cabin window, which was due to a leak behind the window frame. I repaired the leak a few years ago however it took until 2015 for the core to get soft in this area. Not wanting to damage the factory deck in order to repair such a small area, I chose to repair it from underneath inside the cabin. I did a similar repair to the deck around the haws tube when the original restoration on this boat was done and it worked out really well. This time I thought I'd post the way I that I'm doing this thinking that it may benefit other members. Keep in mind that this repair is for small, accessible areas. Large or multiple areas may require a complete deck repair from the top side.

To get the job started, I removed the lower trim panel below the window and exposed the staples that hold the headliner in place in this area. Next I removed the staples and flipped down the headliner exposing underside of the deck. To find exactly where to start the repair, I tapped on the underside of the deck with a plastic hammer and worked my way along until I heard a dull thud. To keep things simple and not create allot of fiberglass dust inside the cabin, I chose to use a hole saw to cut the access to the rotted core. After cutting the 2 access holes, I was able to reach into the core area and scrape out the rotted wood and did so until I hit solid wood both fore and aft of the access holes. This also required making a custom scraper out of sheet metal to reach in between the upper and lower fiberglass.

The next step will be to coat with thickened West System Epoxy, several 2 x 2 square blocks of marine plywood and slip them into the void one after another until the area if filled. This will be followed by a fiberglass roving patch to close the area backup. I can't however continue with this repair until we get another run of warm weather, but when I do I'll be sure to post more on the topic.

Below is a picture of where the job stands as of now.

Image
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB

User avatar
prowlersfish
2019 Gold Support
2019 Gold Support
Posts: 11598
Joined: Sat Nov 05, 2005 6:56 pm
Location: Lower Chesapeake Bay ,Va

Re: Soft Deck (small area) Repair

Post by prowlersfish » Mon Jan 11, 2016 6:48 am

I will be watching , I have a small area to do also .
TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat :D
2009 TROJAN RENDEZVOUS
Port Kinsale 2010 & 2011. Solomons get together 2011.

User avatar
Away
Sporadic User
Posts: 114
Joined: Sat May 09, 2015 5:53 pm
Location: Ontario

Re: Soft Deck (small area) Repair

Post by Away » Mon Jan 11, 2016 11:18 am

Great post. I to shall be watching.

User avatar
MattSC
2019 Gold Support
2019 Gold Support
Posts: 489
Joined: Wed Jan 02, 2008 6:07 pm

Re: Soft Deck (small area) Repair

Post by MattSC » Mon Jan 11, 2016 9:15 pm

I'll be watching too. Just out of curiosity, was your original coring material plywood? Mine was cored with balsa until it reached the end of the non-skid near the fuel fill, then it switched over to a plywood core.

User avatar
Paul
Active User
Posts: 1141
Joined: Fri Jun 10, 2005 1:02 pm
Location: Windsor Ont.

Re: Soft Deck (small area) Repair

Post by Paul » Tue Jan 12, 2016 6:57 am

MattSC wrote:I'll be watching too. Just out of curiosity, was your original coring material plywood? Mine was cored with balsa until it reached the end of the non-skid near the fuel fill, then it switched over to a plywood core.
Hi Matt,

Like yours, mine has a balsa core. I do however have a piece of marine plywood left over from another project that should do the job nicely for this repair.
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB

User avatar
ready123
Ultimate User
Posts: 1841
Joined: Sat Nov 08, 2008 5:53 pm
Location: Mactier, Ontario Canada
Contact:

Re: Soft Deck (small area) Repair

Post by ready123 » Thu Jan 14, 2016 1:41 pm

Only thing I worry about when repairing from below is possibility of getting an air space between underside of deck skin and the core being replacemed.
How are you going to ensure that the pressure from below and wetting will ensure this does not happen?
Are you cutting the plywood into small squares?

I have walked on decks where this air space (read delamination) is present and eventually there is an audible noise and the possibility the deck skin might crack.

Your repairs do look small so likely not a problem... fingers crossed.

Oh... how did you deal with the fact that the upper part of the core will tend to be a larger wet area than the bottom as it is closest to the source and gravity effect?
Michael
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL

User avatar
Bob Giaier
Sporadic User
Posts: 196
Joined: Thu Sep 17, 2009 12:42 pm
Location: Clarkston, Michigan

Re: Soft Deck (small area) Repair

Post by Bob Giaier » Sat Jan 16, 2016 9:00 am

Paul, I'm just finishing up doing the work from below on my deck. Look for my post about a month ago. I also had an area like yours where I drilled a hole a couple inches in diameter and found it dry but a little soft from a leak eons ago. The guy before me mounted some things and then patched the mounting holes. The area did have separation between the existing balsa and the top deck. I always noticed the noise when I walked on it during the summer. I repaired it with bi axle cloth and used a back up block of wood with packing tape on it and big rubber bands to help push up (look at my posting for some pics that are similar). You may not need to do the rubber band block thing if your cloth stays up there. I also drilled a 1/4 inch hole on the top side and put packing tape over it while the repair was being done from below in the areas where I saw the separation. Then I removed the packing tape on the deck and using a cheap syringe, I injected epoxy from above to take care of the gaps between the deck and balsa. There were only a few top holes required. I talked to the a West Systems Application guys about epoxying from top. They told me to finish it off with a gel coat repair kit that you can get from West Marine for about $30bucks. Leave a depression when you apply the epoxy so ere's room for the gel coat. have the repair kit and am waiting for a warm day to use it. The syringes I got from a wood crafter store I my area $6 bucks for 6 syringes. But like I said I saw the separation between the top deck and balsa when I was doing the repair. That's why I added the holes on the top deck.

User avatar
Paul
Active User
Posts: 1141
Joined: Fri Jun 10, 2005 1:02 pm
Location: Windsor Ont.

Re: Soft Deck (small area) Repair

Post by Paul » Sat Jan 16, 2016 7:11 pm

ready123 wrote:Only thing I worry about when repairing from below is possibility of getting an air space between underside of deck skin and the core.....Are you cutting the plywood into small squares?
Hi Michael,

The wood will be cut into 2 inch squares which will fit nicely thru the holes. As for the gaps in the core area, the wood will slip in snuggly but not tightly. The pieces are coated with 105 resin and the leading edges (direction of insertion) will have a generous amount of thickened epoxy resin (406 silica)on them. As the subsequent pieces are inserted the thickened resin gets squeezed into any voids between, above and below them. This will effectively bond the underside of the deck, the core and the bottom layer of glass together.

Also, inserting the square blocks thru round holes then sliding them fore or aft into position makes it easy to hold them in position while the resin hardens. The only one that is a little tricky is the one that will sit center in the open hole. It the last piece to go in and usually has to be cut into a custom shape. When this one goes in, it will be coated with a very thick 406 mixture to prevent gravity from letting it fall out.
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB

User avatar
Paul
Active User
Posts: 1141
Joined: Fri Jun 10, 2005 1:02 pm
Location: Windsor Ont.

Re: Soft Deck (small area) Repair

Post by Paul » Sat Jan 16, 2016 7:28 pm

Bob Giaier wrote:....used a back up block of wood with packing tape on it and big rubber bands to help push up (look at my posting for some pics that are similar). You may not need to do the rubber band block thing if your cloth stays up there.
Hi Bob,

For this type of repair, I like to use roving as opposed to bi-axial matting because it's a little easier to roll into place. In order to hold it in place without gravity removing it for me, I cheat a little and add a little 406 silica to the resin to thicken it so that it has less of a tendency to sag or drip which holds the patch firmly in place. When doing this however, it's important not to make the resin too thick or it won't properly saturate the roving.
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB

User avatar
P-Dogg
2019 Forum Supporter
2019 Forum Supporter
Posts: 820
Joined: Wed Jun 22, 2011 7:15 pm
Location: Near Baltimorgue, where Maryland proves to the nation every day that gun control doesn't work.

Re: Soft Deck (small area) Repair

Post by P-Dogg » Sun Jan 17, 2016 8:06 am

won't properly saturate the roving
This can be handled by saturating the roving with unthickened resin first, then applying the thickened mixture. Wax paper is your friend, as you can place some on a flat surface, work the resin into the cloth, then pick-up wax paper and cloth together. It is less messy, and if you leave the wrap in place while it cures, you'll get a smooth surface. It seems like for such a small area, I would dispense with the core and just fill the void with thickened epoxy. Cores are used in manufacturing mostly to save weight and expense, especially where the free span is large. There appears to be not a lot of weight savings, expense, or expanse involved here. And with epoxy forced in under pressure, you can avoid the void issue. The stuff from Six10 is reasonable to work with, although Jamestown Distributors carries a similar, less expensive, product. Good luck, and do keep us posted.
I needed a less expensive hobby, so I bought a boat!

User avatar
lawyerdave71
Moderate User
Posts: 422
Joined: Sat Dec 03, 2011 8:24 pm
Location: Chicago, Illinois

Re: Soft Deck (small area) Repair

Post by lawyerdave71 » Sun Jan 17, 2016 9:41 am

I'm watching too!! :shock:
Captain Dave -

1978 F30 Flybridge Express

User avatar
Paul
Active User
Posts: 1141
Joined: Fri Jun 10, 2005 1:02 pm
Location: Windsor Ont.

Re: Soft Deck (small area) Repair

Post by Paul » Sun Jan 17, 2016 11:33 am

P-Dogg wrote:
won't properly saturate the roving
This can be handled by saturating the roving with unthickened resin first, then applying the thickened mixture. Wax paper is your friend, as you can place some on a flat surface, work the resin into the cloth, then pick-up wax paper and cloth together. It is less messy, and if you leave the wrap in place while it cures, you'll get a smooth surface.
P-Dogg,

Great idea on the non-thickened resin, this is now part of the plan. As for the core, I prefer the use of wood to replace it. My thinking here is if this boat ever required a complete core job, it would be easier to remove this area repaired with wood as opposed an epoxy filled area. My hope is that this would never happen however if it did, the person doing the work would be glad the repair was don this way.
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB

User avatar
ready123
Ultimate User
Posts: 1841
Joined: Sat Nov 08, 2008 5:53 pm
Location: Mactier, Ontario Canada
Contact:

Re: Soft Deck (small area) Repair

Post by ready123 » Sun Jan 17, 2016 10:08 pm

Paul wrote:
ready123 wrote:Only thing I worry about when repairing from below is possibility of getting an air space between underside of deck skin and the core.....Are you cutting the plywood into small squares?
Hi Michael,

The wood will be cut into 2 inch squares which will fit nicely thru the holes. As for the gaps in the core area, the wood will slip in snuggly but not tightly. The pieces are coated with 105 resin and the leading edges (direction of insertion) will have a generous amount of thickened epoxy resin (406 silica)on them. As the subsequent pieces are inserted the thickened resin gets squeezed into any voids between, above and below them. This will effectively bond the underside of the deck, the core and the bottom layer of glass together.

Also, inserting the square blocks thru round holes then sliding them fore or aft into position makes it easy to hold them in position while the resin hardens. The only one that is a little tricky is the one that will sit center in the open hole. It the last piece to go in and usually has to be cut into a custom shape. When this one goes in, it will be coated with a very thick 406 mixture to prevent gravity from letting it fall out.
Paul,

My question is when you slide your block into the visible circle and push it into the unopened area (how far do they go) how do you ensure that the top epoxy coated piece of wood is touching the underside of the top deck?
I did what you are doing on my bridge floor but did it from the top so that as I pushed the pieces in their coating of epoxy was rubbing on the underside of the deck, I had to push them in firmly..... there were some spots that I felt the pieces slid in too easily but nothing I could do as they were two feet away from the opening. Guess what those spots when walked on flexed and made some noise!
Were I to do it again I would do it like I did the main decks by cutting the top skin off thus ensuring no air spaces and lack of contact with top skin/deck on core replacement.
Michael
Rum is the reason Pirate's have never ruled the world
Done Dreamin'
1987 President 43' Twin Lehman 225SP Turbo
Highfield 310 Ally 15 HP Yamaha 2cycle
1978 F32 Sedan twin 318 Chry SOLD
Safe Cove Marina, Port Charlotte, FL

User avatar
Paul
Active User
Posts: 1141
Joined: Fri Jun 10, 2005 1:02 pm
Location: Windsor Ont.

Re: Soft Deck (small area) Repair

Post by Paul » Tue Jan 19, 2016 7:38 pm

ready123 wrote: My question is when you slide your block into the visible circle and push it into the unopened area (how far do they go) how do you ensure that the top epoxy coated piece of wood is touching the underside of the top deck?
I did what you are doing on my bridge floor but did it from the top so that as I pushed the pieces in their coating of epoxy was rubbing on the underside of the deck, I had to push them in firmly..... there were some spots that I felt the pieces slid in too easily but nothing I could do as they were two feet away from the opening. Guess what those spots when walked on flexed and made some noise!
Were I to do it again I would do it like I did the main decks by cutting the top skin off thus ensuring no air spaces and lack of contact with top skin/deck on core replacement.
Hi Michael,

I know what you're saying about sliding them in, doing this basically wipes the epoxy off of the top and bottom of the block. As I stated in an earlier post, " The pieces are coated with 105 resin and the leading edges (direction of insertion) will have a generous amount of thickened epoxy resin (406 silica)on them. As the subsequent pieces are inserted the thickened resin gets squeezed into any voids between, above and below them. This will effectively bond the underside of the deck, the core and the bottom layer of glass together." Basically I'm pushing a generous amount of epoxy in like a snow plow on the front of each block and as they come up against the previous block, the epoxy gets squeezed into any existing voids. It's a path of least resistance thing. Also, the furthest that I'm sliding these pieces in is approximately 6-8 inches. If I had to go further than that, I'd make some more holes. If it was a large area, I agree that I would cut the top deck out to get to it however as stated in the subject line it's a "small area" and I just couldn't bare ruining my pristine factory deck to repair it.

A for the results that I'm expecting, I' did a similar repair on the deck between the haws tube and windlass during the original restoration of this boat and it's solid. No flexing and no noise. I'm hoping for a repeat performance.

Unfortunately, I now have to wait for a little warmer weather before continuing with this repair.
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB

User avatar
Paul
Active User
Posts: 1141
Joined: Fri Jun 10, 2005 1:02 pm
Location: Windsor Ont.

Re: Soft Deck (small area) Repair

Post by Paul » Sun Feb 07, 2016 10:33 pm

Below are a few more pictures from the beginning of this job. First is the coring tool made of a strip of light gauge sheet metal with a twist and bend at one end for digging at the core wood, then a handle bent at the other end.(not pictured) The next picture is the rotted core that was dug out from between the layers of glass. Then once I hit this wet but solid wood in the last picture, I stopped digging. It will have plenty of time to dry before I epoxy in the new wood.

Image

Image

Image
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB

Post Reply