Removing silicone residue from gellcoat

[Spindrift NH]

I removed a leaking acrylic dead light on my '88 Catalina 30. Before I attempt to install a new piece of acrylic I need to remove all of the existing residue. I have used a painters 5 in one putty knife to get most of the adhesive off but there is still a thin film. I have tried an abundance of acetone but it won't even touch it. Does anyone know what'll work?

 

[centerline]

I removed a leaking acrylic dead light on my '88 Catalina 30. Before I attempt to install a new piece of acrylic I need to remove all of the existing residue. I have used a painters 5 in one putty knife to get most of the adhesive off but there is still a thin film. I have tried an abundance of acetone but it won't even touch it. Does anyone know what'll work?

Use ether, or what is known as starting fluid.... spray it on, keep it wet by spraying it when it starts to dry. It evaporates quickly, but in a few minutes the silicone will be softened, all wrinkled up and easily removed.

 

[Charlie Jones s/v Tehani]

Dynamite??

But a residue will STILL be there. I detest Silicone. Won't allow the stuff on the boat

 

[centerline]

Dynamite??

But a residue will STILL be there. I detest Silicone. Won't allow the stuff on the boat

First step is to cause the silicone to lose its grip on the surface of what ever it's attached to.... then it is just a matter of cleaning and prepping the surface for the new adhesive to stick to.

Clean the surface as you would for any surface that has had automotive wax or polish on it, that you want to repaint or reseal.....

As for silicone use on the boat, I will agree the automotive brands of silicone has very little use on a boat, unfortunately most people don't know this so they use the wrong stuff with terrible results.... a good structural adhesive silicone is an excellent product when used in the right application.

I have worked successfully with silicone for many years in many different applications, and as much as some people have had bad luck with it early on and then never have taken the time to learn how to ovecome its quarks, in some cases it is still the best product to use.....

I am a proponent of using silicone when it's used properly in the correct application, but I also use many other adhesive sealers as well....
Any sealer, adhesive or not, if its used carelessly with out the proper prep work, it will fail prematurly.

 

[agprice22]

Is the gelcoat smooth? Use a razor blade. You should be able to remove it all, and then clean with acetone.

 

[Spindrift NH]

Use ether, or what is known as starting fluid.... spray it on, keep it wet by spraying it when it starts to dry. It evaporates quickly, but in a few minutes the silicone will be softened, all wrinkled up and easily removed.

Thanks for the reply. I'll give ether a try.
To be fair to silicone, I'm not sure what type of adhesive this is but it feels and acts like silicone. From what I understand the proper adhesive for this application is Dow 795. I've never used it nor have I seen it cured so it's possible that that's what I'm dealing with.

 

[Spindrift NH]

Is the gelcoat smooth? Use a razor blade. You should be able to remove it all, and then clean with acetone.

The gelcoat is fairly smooth but not glass and the acetone won't lift the rest.

 

[agprice22]

The gelcoat is fairly smooth but not glass and the acetone won't lift the rest.

So the silicone is in the pores. Sand with 600 grit. That is how I removed adhesive residue from the hull after removing a vinyl name sticker. Acetone would not remove that either. Nothing I tried removed it.... Except sand paper.

Thanks,

Andrew

 

[agprice22]

Thanks for the reply. I'll give ether a try. To be fair to silicone, I'm not sure what type of adhesive this is but it feels and acts like silicone. From what I understand the proper adhesive for this application is Dow 795. I've never used it nor have I seen it cured so it's possible that that's what I'm dealing with.

Dow 795 is black and remains very soft. It looks like tar. It is easy to use, and it cleans up with acetone, but... It could leave a shadow.

Thanks,

Andrew

 

[Bill Roosa]

denatured alcohol will lift silicon completely. you can get a pint used for stove fuel for $10 or go over to the boat chemical isle and get a gallon for $15. Pretty handy stuff, right up there with acetone.

 

[Charlie Jones s/v Tehani]

Well, after running a furniture repair and refinishiing shop for 25 years, and constantly battling silicone residue, from furniture polishes, I come by my dislike quite honestly. That residue will persist even after a piece is stripped, AND acetone washed. Causes "fish eyes" in the finish.

And it is a bear to get rid off. Best solution is Smoothie, which is known in the trade as "fisheye killer' which goes into the lacquer or polyurethane in the gun. Basically adds silicone to the finish while you are spraying, so it all flows out. Sometimes even THAT doesn't work first try.

So say what you will- I detest the stuff

 

[Spindrift NH]

Dow 795 is black and remains very soft. It looks like tar. It is easy to use, and it cleans up with acetone, but... It could leave a shadow.

Thanks,

Andrew

Thanks for the description, I must be dealing with a black silicone.

I'll put denatured alcohol on my must try list!

Thanks

 

[Joe2954]

Cleaning silicone from an Rv, I ordered a silicone remover but haven't used it yet. What has been working is soaking the silicone in mineral spirits, scrape, repeat. I put a paper towel over the area and wet it with the spirits.
Surprisingly a simple flour water paste left to dry will lift some of the residue.

 

[Apex]

IPA (not beer) but Isopropyl alcohol. Then finish with a fine IPA in a cold glass.

 

[Bill Roosa]

There is also a product called Goof-Off. Comes in moist towelettes dispenser and takes off silicone and byutel rubber.

 

[njlarry]

When we replaced the fixed portlights we used a razor blade first followed by acetone. The new Dow 795 adhered to both the gelcoat and the silicone high temp coating on the acrylic portlight and has worked out perfectly since.

 

[njlarry]

When we replaced the fixed portlights we used a razor blade first followed by acetone. The new Dow 795 adhered to both the gelcoat and the silicone high temp coating on the acrylic portlight and has worked out perfectly since.
(should have finished with an IPA when got home)

 

[arf145]

I hate silicone too! But alas it seems Beneteau harbored the opposite emotion--silicone was used for all bedding I've encountered so far. After you've removed all the obvious silicone, the heavy duty version of Goo Gone, a citrus type remover, seems to help. I finish up with denatured alcohol. And then, as agprice22 said, super fine sandpaper if needed. Try to stop short of explosives.

And I always found that more than one beer was required afterward!

 

[mtwolf13]

Sticker Remover.

So the silicone is in the pores. Sand with 600 grit. That is how I removed adhesive residue from the hull after removing a vinyl name sticker. Acetone would not remove that either. Nothing I tried removed it.... Except sand paper.

Thanks,

Andrew

Andrew,

West Marine has a product named Sticker Off or Sticker Ease, whatever. It's in the section with the vinyl letters. I tried everything to get adhesive residue off like you. Finally went to West Marine and found the stuff. Put the stuff on, wait a minute or two and the residue rubbed right off with a rag. Couldn't believe it.

John

 

[agprice22]

Andrew, West Marine has a product named Sticker Off or Sticker Ease, whatever. It's in the section with the vinyl letters. I tried everything to get adhesive residue off like you. Finally went to West Marine and found the stuff. Put the stuff on, wait a minute or two and the residue rubbed right off with a rag. Couldn't believe it. John

Aha! How about that. I will try that if I get the opportunity. Luckily, the entire hull needed sanding and refinishing, so no loss of effort there.

Thanks,

Andrew