Gelcoat! Wax or no wax?

[chriscraft254]

I have rebuilt a houseboat upper deck. It is glassed in and ready to gelcoat.I will be rolling this on, not spraying.

Question is, do I use waxed gel coat for all three coats or just for the last coat? I'm thinking wax in all three coats. After cure time,between coats, what do I remove the wax with? Acetone?

Do I need to sand between coats and what roller would you recommend?

Reason for gelcoat instead of paint, is durability, this will be walked on all the time.

Also, what non skid additive should I be using in this? And should that be added just to the last coat of gel?

Just checking my thought processing here, thanks.

 

[Yacht Dr.]

Re: Gelcoat! Wax or no wax?

Lots of questions here ..

I have rebuilt a houseboat upper deck. It is glassed in and ready to gelcoat.I will be rolling this on, not spraying.

Question is, do I use waxed gel coat for all three coats or just for the last coat? I'm thinking wax in all three coats. After cure time,between coats, what do I remove the wax with? Acetone?

Do I need to sand between coats and what roller would you recommend?

Reason for gelcoat instead of paint, is durability, this will be walked on all the time.

Also, what non skid additive should I be using in this? And should that be added just to the last coat of gel?

Just checking my thought processing here, thanks.

Pics Please.

Just nonskid your laying down ? or are you basecoating gel before you skid...

Typically you add the wax to the whole batch of gel. But depending on your cure/work times that may not be possible without reprep ( wax or not ).

Griptex is your best bet for then nonskid.

YD.

 

[chriscraft254]

Re: Gelcoat! Wax or no wax?

Working time will be minimal because it will be done outdoors, the boat is slipped. But it is just one very large flat surface, about 9'x12' area. This is a total rebuild. I will be putting atleast one base coat down. But probably 3 coats total just for thickness and durability. Aren't some gel coats already mixed with the wax?

If I'm not thinking correctly, please tell me. Been a long time since I messed with this large a project.

Lots of questions here ..



Pics Please.

Just nonskid your laying down ? or are you basecoating gel before you skid...

Typically you add the wax to the whole batch of gel. But depending on your cure/work times that may not be possible without reprep ( wax or not ).

Griptex is your best bet for then nonskid.

YD.

 

[Yacht Dr.]

Re: Gelcoat! Wax or no wax?

Really need them pics ..

YD.

 

[chriscraft254]

Re: Gelcoat! Wax or no wax?

Ok, here are some pics, all I could find right now. Basically the upper deck was overlayed with 3/8 inch ply in one direction and then overlayed again in the opposite direction. It was screwed with exterior deck screws made for composite material. These type of screws are coated really well and hold better because of the thread design. Each layer was screwed approximately every 8 inches. The edges every 4 inches.

The main reason for the overlay, was who ever did the repairs in the past did not do very good glass work and it was leaking. Instead of trying to patch it, I felt it was better just to overlay and make it stronger. The boats upper deck use to flex quite a bit, not you could park a truck on it! The extra weight was really a non-issue because we are talking about a 35 ft houseboat with plenty off power.

Like I said, these are the only pics I have on this computer right now. Don't mind my buddy!

 

[ondarvr]

Re: Gelcoat! Wax or no wax?

You only need wax in the last coat.

Many things will work as a non skid additive, sand is good, but if you ever need to re-do anything it's a nightmare to grind it. There are other softer products sold for this purpose that work well too, check your local big hardware store, they should have a couple options.

Do not put the final coat on in direct sunlight, if you do there is a very good chance the surface will stay tacky even with wax.

 

[chriscraft254]

Re: Gelcoat! Wax or no wax?

I know what additive I'm going to use, just was asking in which coat should I be adding it to? If the first two coats of gel do not have wax, will I be able to walk on the area with out sticking to apply the next coat?

You only need wax in the last coat.

Many things will work as a non skid additive, sand is good, but if you ever need to re-do anything it's a nightmare to grind it. There are other softer products sold for this purpose that work well too, check your local big hardware store, they should have a couple options.

 

[ondarvr]

Re: Gelcoat! Wax or no wax?

Yes you will be able walk on the first two coats of gel coat, that won't be a problem.

I normally add the non skid to the first coat, but it depends on how aggressive you want the non skid surface to be.

 

[chriscraft254]

Re: Gelcoat! Wax or no wax?

Ok, well, I decided to go with the waxed gel coating for all three coats. I just have to wash it between coats with a good detergent to get the wax off. then I rotary sanded to get a good bond with the following coat. This went really smooth. Knock on wood!!! I will be putting another coat on with the non-skid added to it tmrw. This is how she looks now. Think its looking pretty good. The rest of the lower decks and upper will get sanded down next year,soft spots fixed and then gelcoated to match this.

 

[oops!]

Re: Gelcoat! Wax or no wax?

i dont know how i missed this...... sorry chris.

ondarvr has it right...

the reason for wax in gellcoat.....is because air inhibits gellcoat/resin from curing....so.....if wax is in the mix....it will come to the surface of the gell when its going thru cure.

now......that means......becasue wax is a RELEASE AGENT (gellcoat wont stick to wax) there might be bonding issues......(i see you sanded it....thats good)
for the coats next year.......just use wax in the final coat......

because the gell wont be completly cured when you hit it with the second coat.......your feet will kinda stick to it.....not much....but lets say ....tacky.....the gell wont come up and stick to your shoes...so you are good......just make sure your shoes are clean.....so you are not bonding gellcoat to dirt.

.........having said all that..........just look at those pics......wow......hard as nails.. and no problems for 40 years......what a product.

 

[chriscraft254]

Re: Gelcoat! Wax or no wax?

I appreciate all the advice. I know there are different ways of doing things. I went with the gelcoat with wax because I did not want things sticking to this being I'm doing it outdoors, figure it might dry/cure quiker with the wax in it. Also wasn't sure I could get back to it the next day. Also didn't want to walk on it with it being tacky.

I was told that using a strong detergent like wisk would get the wax off for recoating, I sanded inbetween coats to make sure I got a bond. I guess this is pretty normal application around here for these houseboats.

I hated to go against the advise here, but I really thought that each layer being hard by morning would be a good thing. When I coated the second coat it seemed to bond really well with no problems of the gel slipping around or expelling like when over a grease spot or something. I guess time will tell and I do still have a final coat to put on. I'm kinda knocking on wood, because this went alot smoother than I thought it was going to.

I used one of those tiny rollers, it worked perfect, layed down nice.

 

[ondarvr]

Re: Gelcoat! Wax or no wax?

It may bond well enough to survive, but adding wax to each coat and letting it get hard is absolutely the wrong way to do it, the tackiness of the surface is what you want, not something you should try to eliminate. Washing it with soap and water may remove most of the wax, but it doesn't change the fact that the surface has sealed itself off chemically (cured) and bonding to this surface can be more difficult. Sanding the surface does create a mechanical bond, which will work well enough, but you need to sand 100% of the surface, this means even the low areas of the texture left by the roller, doing this sands off almost 100% of what you put down.

Also, adding the nonskid to the first coat is better, but it can depend on which product you used. This gives you more gel coat over the grit, which can prevent it from showing through and allows you to adjust how aggressive the surface is.

This job can easily be done in one day.

 

[ondarvr]

Re: Gelcoat! Wax or no wax?

By the way, did you use wax in the final layer of resin when you were glassing the surface, also how long did it sit between finishing the glass work and the first application of gel coat, and how did you prep the surface before applying the gel coat?