Replacing Cabin Sole

RoyS

.
Jun 3, 2012
1,739
Hunter 33 Steamboat Wharf, Hull, MA
The cabin sole in my forty year old boat needs to be replaced. Spent yesterday tearing the old Teak and Holly plywood out. What I found underneath was silicone caulking that was spread out in a haphazard fashion to hold the plywood to the fiberglass liner. I intend to install PlasDECK flooring in place of the old plywood. PlasDECK is installed with a glue supplied by the manufacturer. My question is how do I completely remove the old silicone? It can be peeled up with a putty knife or similar tool but my fear is that it is still embedded in the fiberglass. Nothing will stick to silicone and I am worried that my new floor will lift. Any suggestions on how to completely remove the silicone?
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Last edited:
Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
Roy.
I used


Goo Gone Pro Power – For Multiple Surfaces
Goo Gone Pro Power - For Multiple Surfaces

To help remove the silicone caulk in places around my windows. It worked mostly. Still there is/was scraping and a little praying.

I think after the big windstorm and rain I have a little more work to do. I had water intrusion. Not a lot, but enough to warrant further inspection and work. Bummer.
 
Jun 21, 2004
2,532
Beneteau 343 Slidell, LA
Roy,
Have you considered a composite material that is the approximate thickness of the old plywood sole. You could screw the new decking to the liner, so there would be no issues with any adhesive bonding because of silicone residue. Also, if you ever need to run new plumbing or wiring, it would be much easier to unscrew the flooring rather than ripping it up. The flooring on my Beneteau is screwed in place and it is easy to remove for accessing & cleaning the bilge areas. Amazing how much crud & critters build up in those areas and I have a dry bilge mostly.
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
I like @BigEasy 's idea of a composite replacement which is the same thickness as the old T&H plywood. And that composite would be plywood sections covered with PlasDECK and then screwed to the liner. Screws look fine if they are strategically placed and then covered with wooden plugs inserted (if the composite is thick enough).
 
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Likes: LloydB
Apr 8, 2010
1,942
Ericson Yachts Olson 34 28400 Portland OR
I like @BigEasy 's idea of a composite replacement which is the same thickness as the old T&H plywood. And that composite would be plywood sections covered with PlasDECK and then screwed to the liner. Screws look fine if they are strategically placed and then covered with wooden plugs inserted (if the composite is thick enough).
I have always found it better to countersink each screw so that the head is flush or gnat's eyelash below the surrounding surface. Use bronze square drive screws and they will hardly be noticeable against the teak-color surface. This way you can easily take up the sole sections for servicing pumps, hoses, or wiring in the future.
 
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Likes: ggrizzard
May 7, 2012
1,338
Hunter e33 Maple Bay, BC
My question is how do I completely remove the old silicone?
My question is do you really need or is it even possible to remove "all" of the old silicone including the residual or embedded silicone in the fiberglass? Ideally yes but absolutely necessary???? This is a quote from a webpage discussing this issue (link here). I would definitely touch base with PlasDECK support to see what their advice is.

"At least chemically speaking, it is theoretically possible that silicone adheres to silicone, but the basic prerequisite is that the silicone sealant on the same chemical basis. This means that the old silicone joint must be on the same type of crosslinking as the new silicone.
Acetate silicone on acetate silicone
Oxime silicone
on oxime silicone
Alkoxysilicone
on alkoxysilicone
Nevertheless, this is no guarantee that new silicone adheres to the old silicone joint."
 
Jul 26, 2009
291
. . .
I worked through the same situation a few years ago. Looked almost identical to what you've posted above, including what appears to be a myriad of different adhesives. After trying a few different approaches, a rubber mallet and very sharp 2" chisel held at a shallow angle made short order of what you're looking at. It left behind a smooth surface with just a residual tackiness in a few spots. For the most part, that cleaned up with acetone (at least to the touch). It's inevitable that chemical traces of the previous adhesives will be left behind (even if you can't feel it). As already mentioned, you could try sanding the liner after removing/cleaning the existing adhesive, but there will always be something left behind.

I'm with @Hello Below. If silicone was used you won't get it all off, but I'd be surprised if the residual traces result in bonding failure of the new flooring. If you look closely, you'll see a lot of naked surface area in between the existing beads of adhesive. That's the original liner and hasn't come in contact with other adhesives yet. If applied thoughtfully, the new adhesive will bond to at least those surfaces provided they are clean and dry (and the temperature is warm enough). I would lay up one of the smaller sections of new sole first and evaluate over the Winter/early Spring before going all out with the rest of the new installation.

Good luck. It's a fun project and the results are something you'll enjoy every time you go below decks.
 
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Likes: Leeward Rail
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
"At least chemically speaking, it is theoretically possible that silicone adheres to silicone, but the basic prerequisite is that the silicone sealant on the same chemical basis.

@Hello Below , I wasn't going to go there, but yes, you're absolutely right. The only thing that sticks to silicone is silicone.

I didn't want to mention it as I could just hear the armchair chemists lining up to shoot this all to hell. Nothing sticks to silicone and nobody should stick no silicone on their boat :angry:. If you own a 1990+ production boat, the frameless window installations are 100% silicone. And what's DC 795 :laugh: ?

Back in 2007, I was looking at frameless window repair and thought I'd go right to the horse's mouth. In return, I got this e-mail from Dow Corning regarding applying new DC795 over old DC795 :
________________________________________________________________________________

Dear Ralph,

This is a follow-up message from Dow Corning to your recent inquiry. Yes, 795 will adhere to old 795 as long as the old cured 795 is clean, dry, and frost free. Below I have provided information that discusses the removal and replacement of cured silicone sealant and our recommendations.

Removal and Replacement of Cured Silicone Sealant

A properly designed and installed silicone joint will typically last 20 years without need of replacement. In instances where the joint has experienced mechanical or other damage and replacement is required, follow the procedures below. Assess the problem with the joint.

1. If the sealant is cured properly and performing application but its appearance is poor (i.e., due to improper tooling), then cleaning the sealant surface with a solvent and recapping the joint should be sufficient.

a) Clean sealant with a solvent (i.e., xylene, toluene) to remove dirt. Allow solvent to evaporate.

b) Remask the joint.

c) Apply a thin bead of fresh sealant over the cured sealant.

d) Dry tool the sealant.

e) Remove the masking material.

2. If the sealant is mechanically damaged and a recapping will not improve the joint appearance, then remove the section of old sealant and replace it.

a) Cut away the old sealant. If excellent adhesion to the substrate is still maintained, then leave some sealant at the edges of the joint (up to 0.08"/2 mm thick).

b) If adhesion to the substrate is poor, then remove sealant down to the substrate and clean the substrate and recondition if necessary (i.e., clean with xylene and prime with appropriate primer).

c) Mask the joint.

d) Reapply the sealant. (If resealing does not occur on the same day, the joint will have to be recleaned using a solvent such as xylene or toluene before applying the fresh sealant.)

e) Dry tool the joint.

f) Remove the masking material.

g) Check adhesion after the sealant has cured for 7 days.


Thank you for contacting Dow Corning. If I can be of further assistance, feel free to contact me.

Best Regards,

Mary
DOWCORNING.COM | CONTACT AN EXPERT | FIND A DISTRIBUTOR | CUSTOMER SUPPORT | SUBSCRIBE
Mary Altenburg
Technical Information Center
Dow Corning Corporation
We help you invent the future ™
Phone: (989) 496-6000 Fax: (989) 794-5900
Email: tech.info@dowcorning.com

NOTICE: (Please Read Carefully):
Dow Corning believes that any product use recommendation or product information presented is an accurate description of the typical characteristics or uses of the product, but it is your responsibility to thoroughly test the product in your specific application to determine its performance, efficacy, and safety under your conditions of use. Suggestions of uses should not be taken as inducements to infringe any patent. Unless Dow Corning provides you with a specific written warranty of fitness for a particular use, Dow Corning's sole warranty is that the product as supplied will meet Dow Corning's then current sales specifications. DOW CORNING SPECIFICALLY DISCLAIMS ANY OTHER EXPRESS OR IMPLIED WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND OF FITNESS FOR PARTICULAR PURPOSE. Your exclusive remedy and Dow Corning's sole liability for breach of warranty is limited to refund of the purchase price or replacement of any product shown to be other than as warranted, and Dow Corning expressly disclaims any liability for incidental and consequential damages.

Good News!! Many Dow Corning technical data sheets as well as Material Safety Data Sheets (MSDS) are now available online! Just visit our site: www.dowcorning.com

You may search under the product name or number, product family or industry. Some of this information is also available in several languages - just choose which country and language you want.


_____________________________________________________

Being from Missouri, I had to try it to satisfy myself and yes, the joint is just as strong as the parent material. As you have stated, I would agree that only like silicone to like silicone would be a good idea.

There's still the matter of building up the PlasDECK to the thickness of the old plywood which takes us back to where we started.

So many options, so little time :facepalm:.
 
  • Helpful
Likes: Hello Below
Jun 21, 2004
2,532
Beneteau 343 Slidell, LA
The screws holding my composite panels to fiberglass grid are countersunk with no bungs to conceal the head. Appearance is acceptable. I certainly understand production builders using adhesives to attach the sole for reduced cost; however, it is a major ordeal to remove and impossible to do so without destroying the panels.
 
Aug 2, 2009
637
Catalina 315 Muskegon
I really like the sole in my Catalina 315, which is marine ply covered with some rugged vinyl that looks just like teak and holly. It's screwed to the underlying glass with dark bronze colored screws. Sure, it looks a little "production-boaty", but overall...looks great and is easy to live with.
That's how I'd do it.
 
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Likes: LloydB
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
@Hello Below , I wasn't going to go there, but yes, you're absolutely right. The only thing that sticks to silicone is silicone.

I didn't want to mention it as I could just hear the armchair chemists lining up to shoot this all to hell. Nothing sticks to silicone and nobody should stick no silicone on their boat :angry:. If you own a 1990+ production boat, the frameless window installations are 100% silicone. And what's DC 795 :laugh: ?

Back in 2007, I was looking at frameless window repair and thought I'd go right to the horse's mouth. In return, I got this e-mail from Dow Corning regarding applying new DC795 over old DC795 :
________________________________________________________________________________

Dear Ralph,

This is a follow-up message from Dow Corning to your recent inquiry. Yes, 795 will adhere to old 795 as long as the old cured 795 is clean, dry, and frost free. Below I have provided information that discusses the removal and replacement of cured silicone sealant and our recommendations.

Removal and Replacement of Cured Silicone Sealant

A properly designed and installed silicone joint will typically last 20 years without need of replacement. In instances where the joint has experienced mechanical or other damage and replacement is required, follow the procedures below. Assess the problem with the joint.

1. If the sealant is cured properly and performing application but its appearance is poor (i.e., due to improper tooling), then cleaning the sealant surface with a solvent and recapping the joint should be sufficient.

a) Clean sealant with a solvent (i.e., xylene, toluene) to remove dirt. Allow solvent to evaporate.

b) Remask the joint.

c) Apply a thin bead of fresh sealant over the cured sealant.

d) Dry tool the sealant.

e) Remove the masking material.

2. If the sealant is mechanically damaged and a recapping will not improve the joint appearance, then remove the section of old sealant and replace it.

a) Cut away the old sealant. If excellent adhesion to the substrate is still maintained, then leave some sealant at the edges of the joint (up to 0.08"/2 mm thick).

b) If adhesion to the substrate is poor, then remove sealant down to the substrate and clean the substrate and recondition if necessary (i.e., clean with xylene and prime with appropriate primer).

c) Mask the joint.

d) Reapply the sealant. (If resealing does not occur on the same day, the joint will have to be recleaned using a solvent such as xylene or toluene before applying the fresh sealant.)

e) Dry tool the joint.

f) Remove the masking material.

g) Check adhesion after the sealant has cured for 7 days.


Thank you for contacting Dow Corning. If I can be of further assistance, feel free to contact me.

Best Regards,

Mary
DOWCORNING.COM | CONTACT AN EXPERT | FIND A DISTRIBUTOR | CUSTOMER SUPPORT | SUBSCRIBE
Mary Altenburg
Technical Information Center
Dow Corning Corporation
We help you invent the future ™
Phone: (989) 496-6000 Fax: (989) 794-5900
Email: tech.info@dowcorning.com

NOTICE: (Please Read Carefully):
Dow Corning believes that any product use recommendation or product information presented is an accurate description of the typical characteristics or uses of the product, but it is your responsibility to thoroughly test the product in your specific application to determine its performance, efficacy, and safety under your conditions of use. Suggestions of uses should not be taken as inducements to infringe any patent. Unless Dow Corning provides you with a specific written warranty of fitness for a particular use, Dow Corning's sole warranty is that the product as supplied will meet Dow Corning's then current sales specifications. DOW CORNING SPECIFICALLY DISCLAIMS ANY OTHER EXPRESS OR IMPLIED WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND OF FITNESS FOR PARTICULAR PURPOSE. Your exclusive remedy and Dow Corning's sole liability for breach of warranty is limited to refund of the purchase price or replacement of any product shown to be other than as warranted, and Dow Corning expressly disclaims any liability for incidental and consequential damages.

Good News!! Many Dow Corning technical data sheets as well as Material Safety Data Sheets (MSDS) are now available online! Just visit our site: www.dowcorning.com

You may search under the product name or number, product family or industry. Some of this information is also available in several languages - just choose which country and language you want.


_____________________________________________________

Being from Missouri, I had to try it to satisfy myself and yes, the joint is just as strong as the parent material. As you have stated, I would agree that only like silicone to like silicone would be a good idea.

There's still the matter of building up the PlasDECK to the thickness of the old plywood which takes us back to where we started.

So many options, so little time :facepalm:.
As noted not all silicone caulks are the same. Caulks like DOW 795 and GE Silpruf have a different chemistry and properties than the cheap stuff bought in a hardware store. 795 and Silpruf are archectural glazing compounds Formulated to hold plate glass windows in place. They have both good adhesive and sealant characteristics. Ordinary silicone does not have these characteristics. If the silicone caulk has a vinegar odor, it is the cheap stuff and will cause issues later on. Silpruf does not and it’s physical characteristics are different, It is a nice caulk to work with. ( I’ve never used 795, so can’t speak to its characteristics).
 
Jun 21, 2004
2,532
Beneteau 343 Slidell, LA
As noted not all silicone caulks are the same. Caulks like DOW 795 and GE Silpruf have a different chemistry and properties than the cheap stuff bought in a hardware store. Silpruf does not and it’s physical characteristics are different, It is a nice caulk to work with. ( I’ve never used 795, so can’t speak to its characteristics).
I have used both; they are used as architectural glazing compounds for securing and sealing glass panels to buildings. Both are great products. Not sure about silpruf; however, 795UV offers some protection to uv exposure. Would think that if is suitable for attaching glass panels to a sky scraper, that it would firmly secure flooring. Probably an overkill!
 

RoyS

.
Jun 3, 2012
1,739
Hunter 33 Steamboat Wharf, Hull, MA
Thank you everyone for your comments. First of all, the PlasDECK material is not the same as the original plywood. PlasDECK is a flexible PVC about 3/16" thick. It is made to look like Teak planking and is normally installed outside on a boat deck. I am installing it inside my cabin. The manufacturer supplies an adhesive which is uniformly applied with a notched trowel; so there is no matching Silicone chemistries here. Also, although there were spaces where no silicone was applied, this new flexible material appears to require a uniform bond to the fiberglass. The company suggested using a grinder with a paint removal disk to remove the Silicone and expose a fresh surface. I think I will try using a wallpaper scraper (razor blade) to remove the majority of the old Silicone. I will then follow that with the grinder and paint removing disk. There is only about forty square feet of area to deal with. I will reassess after these operations.
 
Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
Sounds interesting Roy. I looked at the product. Sounded like they will do the install. Is the DIY option there? Does it affect their warranty?

Are you considering their "Glow in the Dark Lines" option? Seems it might help with those night time needs. Also with Halloween coming glowing in the dark would be right in style.
 
Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
I'll be odd guy out and suggest possibly just removing the old, sanding the liner, and calling it done. Our C&C just has a non slip fiberglass sole. Not as pretty but it is low maintenance.

Painting it may not be durable compared to plasteek though, unlike factory gelcoat non slip.

Then again, my idea of a dream sailboat is one that looks like a ship below, with watertight bulkheads and doors, and no wood in sight. Hehe.


A newbie sailor, marina neighbour actually put parquet flooring in his boat... Looks horrible like parquet does and he made it slippery too. But I digress.
 
  • Ha
Likes: jssailem

19thol

.
May 2, 2014
111
Hunter 30 St.Petersburg, Fl
Since the new flooring is thiner than the old, could you put an underlayment down and attach the new flooring to that?
 
Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
Any suggestions on how to completely remove the silicone?
Google search "Silicone Digestant"
Dow (DOWSIL DS-2025), Prosoco, Swantek, and other makes them.
Obviously, make sure it won't eat the gelcoat.
I would contact the professionals at DOW and ask them.

Edit:

Reportedly you can use vinegar and isopropyl alcohol to soften silicone for easier removal, then use a soft scrub pad... but YMMV
 
Last edited:
Dec 28, 2015
1,837
Laser, Hunter H30 Cherubini Tacoma
Consider a 3m decal removing wheel. Might work. Don’t sand it down until you have it all up or the surface will be contaminated with silicone
 

RoyS

.
Jun 3, 2012
1,739
Hunter 33 Steamboat Wharf, Hull, MA
Yesterday I finished prying all the old plywood up. After that I invented a simple test for the presence of silicone. I placed a piece of masking tape onto an area with obvious silicone residue. The tape had absolutely no adhesion. I took a razor blade and carefully peeled off the residue down to the bare fiberglass and placed the tape down. Only slight adhesion compared to uncontaminated fiberglass. I took the paint stripper grinder disk by hand and sanded the peeled area until the fiberglass felt clean. The tape adhered much better. Not a very scientific test, however it does prove that cured Silicone will certainly prevent anything from sticking to a contaminated surface. As for a contaminated surface remaining after grinding, due to the disk transferring the silicone, we will find out soon. After I scraped up all the Silicone residue with the razor blade, I had reams of the stuff in the form of shavings. I put a few ounces of the Silicone shavings in a container with denatured alcohol and another sample in a container with acetone. After soaking overnight there was no change to the Silicone in either solvent. Regarding Dow's DS 2025; I watched a video on that chemical and they recommended soaking the contaminated part overnight. This is obviously not practical with a boat sole. It is doubtful there is any chemical that could be wiped on and then wiped off and have any effect against the amazingly indestructible Silicone. Grinding today. Thanks again for the suggestions.