Hull Peelers Vs. Sanding

[shamrock]

Here are some photos with all the gelcoat off.

I've washed the boat several times and hope she is drying out. Will use a dehumidifier if need be.

I'm wondering what the white filler stuff is around the prop and the leading edge of the keel. It's also around depth transducer. Should I just leave it and barrier coat over it?

I'm also wondering what the best way to fair it out would be. It's pretty smooth, but I would like to get it as good as possible. What is the process for using a long board on this?

Many thanks

[minaret]

Lookin good, nice work. Are you sure the "filler" isn't gelcoat? As I said earlier, those are exactly the areas I'd expect to see a heavy gelcoat buildup, because they are very difficult to spray in the mold. This means the booth operator has to shoot way too much gel in the mold to get coverage on the hard to get spots, and in some cases they will just brush these spots or even pour gel into the mold and glass over it. Very common. In any case, I would remove it, as its clearly cracked.


Have you checked out my "Nauticat 52 Refit" thread? I posted pics of how we do a bottom there. I wouldn't suggest boarding it out unless you are a racer, although I did it on my bottom just for general principle. Prepare yourself for some grueling labor if you go there.

[shamrock]

Originally Posted by minaret

Lookin good, nice work. Are you sure the "filler" isn't gelcoat? As I said earlier, those are exactly the areas I'd expect to see a heavy gelcoat buildup, because they are very difficult to spray in the mold. This means the booth operator has to shoot way too much gel in the mold to get coverage on the hard to get spots, and in some cases they will just brush these spots or even pour gel into the mold and glass over it. Very common. In any case, I would remove it, as its clearly cracked.

Have you checked out my "Nauticat 52 Refit" thread? I posted pics of how we do a bottom there. I wouldn't suggest boarding it out unless you are a racer, although I did it on my bottom just for general principle. Prepare yourself for some grueling labor if you go there.

Thanks, Minaret.

I have read your refit thread a couple of times and went back last night and went through the bottom job again. That thread is priceless by the way. Thank you of behalf of the entire sailing community!

I agree with your thoughts on not boarding it for practical purposes, but part of me feels like this is (hopefully) the one and only time I'll have this boat down to bare fiberglass and why pass up an opportunity to get is as good as possible. I also want a boat that is as competitive as possible if and when I do the occasional race.

My question is:

Is there any benefit to trying to fair out the boat before applying neat west systems and without doing the 407 slick you referenced, or is that just a fool's errand?

My thought is to maybe use some lacquer or pigment of some kind and run a long board against the hull to identify any high areas and then try to smooth them out as is using some power equipment with heavy grit. I know this might not be the way to get a perfect surface, but could I achieve an incremental improvement without 100+ man hours more into it (as far as I'm concerned, the grueling labor started once I picked up that sander!!)

I'm also concerned that once I start troweling on that 407, I might be doing more harm than good and regret it.

finally, If I grind off the extra thick gel, won't that distort the shape of the hull in those places, how do I build that back up or should I not worry about that. It is the leading and trailing edge of the keel, around the prop aperture, and all over the rudder.

Thanks!

[minaret]

Originally Posted by shamrock

Thanks, Minaret.

I have read your refit thread a couple of times and went back last night and went through the bottom job again. That thread is priceless by the way. Thank you of behalf of the entire sailing community!




You're welcome. Happy to share!




I agree with your thoughts on not boarding it for practical purposes, but part of me feels like this is (hopefully) the one and only time I'll have this boat down to bare fiberglass and why pass up an opportunity to get is as good as possible. I also want a boat that is as competitive as possible if and when I do the occasional race.



I get it. This was precisely my reasoning. I'm not sad I did it. If you got your hull nice and dry, this will certainly be the last time it's bare. Be aware of what you are signing on for though, boarding a bottom is not for normal humans.





My question is:

Is there any benefit to trying to fair out the boat before applying neat west systems and without doing the 407 slick you referenced, or is that just a fool's errand?


Yes, that's a fools errand. That's what the 407 is for.

My thought is to maybe use some lacquer or pigment of some kind and run a long board against the hull to identify any high areas and then try to smooth them out as is using some power equipment with heavy grit. I know this might not be the way to get a perfect surface, but could I achieve an incremental improvement without 100+ man hours more into it (as far as I'm concerned, the grueling labor started once I picked up that sander!!)


If you must go that route, get a rattle can of blaze orange guide coat, cheap marker paint will work. Spritz a guide coat on the bottom and then have at it. It will be immediately obvious where the flaws are. There are numerous reasons for not doing it this way. Your bottom does not need this.

I'm also concerned that once I start troweling on that 407, I might be doing more harm than good and regret it.



Why the concern? Apply the neat coats with pigment. When you start to blow through the 407 you'll see the pigment and know to stop. The double slick of 407 is to give you enough material to get the bottom fair without blowing through. It will be plenty on yours, you did a fine job from looking at the pics.

finally, If I grind off the extra thick gel, won't that distort the shape of the hull in those places, how do I build that back up or should I not worry about that. It is the leading and trailing edge of the keel, around the prop aperture, and all over the rudder.



Yes, once you grind off the gel you will lose the shape and have to fair it back out. And these are of course the hardest areas to fair. The extreme shape is what caused the problem in the first place, and now you must reproduce it from nothing. This is normal.

The beauty of the 407 stage is that lows like this are fairly easy to fair out, just board out the bottom, mark the lows and prep them, then float on some more 407. It usually takes a few extra passes on problem areas like this. Make sure to prep and fill them all at once so you need to mix fewer batches.

Thanks!

Your welcome!

[minaret]

Is your concern your troweling skills? Practice by doing the rudder. Your boat is small enough to do efficiently with three guys in two days. One side per day, one mixer, two trowel men, one goes high the other low. The mixer better know what he's doing and hustle. They will be long days. The rudder will be good practice for one man.

[rocksculpter]

Wow, that was a lot of work. Kind of late now but I wanted to mention when I did my Norsea, with it's imitation lapstrake and not condusive to grinding or pealing, I used a pressure washer sandblaster. Still a lot of time and effort and about a ton of silica sand.

The fairing job was more daunting and tedious. I never want to do that again. To finish, 5 coats of epoxy with barrier coat and 2 coats of epoxy primer (interlux 2000). I find the bottom paint won't stick without the primer.

Looking good, Barry

[shamrock]

Originally Posted by minaret

Is your concern your troweling skills? Practice by doing the rudder. Your boat is small enough to do efficiently with three guys in two days. One side per day, one mixer, two trowel men, one goes high the other low. The mixer better know what he's doing and hustle. They will be long days. The rudder will be good practice for one man.

Thanks, Minaret. That's a great idea and my rudder needs a lot of work due to hurricane damage.

Take a look at the attached photo. I picked a spot that I saw some waves and drew a checkerboard pattern with a permanent marker, then went over it with a board a few times. I was thinking of doing this to identify high areas and just sand a little more carefully or use a board over it.

Either way, I'm sure I will have some time to think this through as I let the hull dry out.

Thanks

[shamrock]

Originally Posted by rocksculpter

Wow, that was a lot of work. Kind of late now but I wanted to mention when I did my Norsea, with it's imitation lapstrake and not condusive to grinding or pealing, I used a pressure washer sandblaster. Still a lot of time and effort and about a ton of silica sand.

The fairing job was more daunting and tedious. I never want to do that again. To finish, 5 coats of epoxy with barrier coat and 2 coats of epoxy primer (interlux 2000). I find the bottom paint won't stick without the primer.

Looking good, Barry

Thanks, Barry. Is that lapstrake the whole bottom?? It's certainly a ton of work...

[minaret]

Originally Posted by shamrock

Thanks, Minaret. That's a great idea and my rudder needs a lot of work due to hurricane damage.

Take a look at the attached photo. I picked a spot that I saw some waves and drew a checkerboard pattern with a permanent marker, then went over it with a board a few times. I was thinking of doing this to identify high areas and just sand a little more carefully or use a board over it.

Either way, I'm sure I will have some time to think this through as I let the hull dry out.

Thanks

Yeah, that looks pretty normal for a boat that was stripped by sanding. As I said before, this is exactly what a peeler is supposed to prevent. This will fair out MUCH faster in the 407 phase. If you have some egregious highs you want to knock down before fairing, go for it. Remember you can dry guide coat. Chalk works too. But really, think about it. Sand fair in solid glass, or fairing compound? This job will be enough of a nightmare without making it harder on yourself.


Have you got some meter readings? How wet is it? What methods are you using to accelerate dry time?

[shamrock]

Originally Posted by minaret

Yeah, that looks pretty normal for a boat that was stripped by sanding. As I said before, this is exactly what a peeler is supposed to prevent. This will fair out MUCH faster in the 407 phase. If you have some egregious highs you want to knock down before fairing, go for it. Remember you can dry guide coat. Chalk works too. But really, think about it. Sand fair in solid glass, or fairing compound? This job will be enough of a nightmare without making it harder on yourself.

Have you got some meter readings? How wet is it? What methods are you using to accelerate dry time?

I just got some moisture readings. It took me a while to get my hands on a good meter.

I used a pinless meter and got readings that were consistently 0-2 percentage points higher that above the water line and deck. My hull is not cored above the water line, The deck and topsides were reading about 8-10% and the bottom was reading between 9.5% and 10.5% pretty consistently.

The rudder was getting 25-30% which I expected. and where my water tanks were were reading slightly higher as well.

I was getting in the mid teens to low twenties with the gelcoat on. I have scrubbed with TSP and powerwashed several times since then over about 5-6 weeks.

My plan was to use a dehumidifier if I was getting high readings but as it is, I think I will just let it sit for a few more weeks and wash it every week or so.

Any thoughts?

When I coat with 105, how many gallons do you think I need for a 35 foot? Also, should I use the fast or slow hardener?

Thank You!

[minaret]

Originally Posted by shamrock

I just got some moisture readings. It took me a while to get my hands on a good meter.

I used a pinless meter and got readings that were consistently 0-2 percentage points higher that above the water line and deck. My hull is not cored above the water line, The deck and topsides were reading about 8-10% and the bottom was reading between 9.5% and 10.5% pretty consistently.

The rudder was getting 25-30% which I expected. and where my water tanks were were reading slightly higher as well.

I was getting in the mid teens to low twenties with the gelcoat on. I have scrubbed with TSP and powerwashed several times since then over about 5-6 weeks.

My plan was to use a dehumidifier if I was getting high readings but as it is, I think I will just let it sit for a few more weeks and wash it every week or so.

Any thoughts?

When I coat with 105, how many gallons do you think I need for a 35 foot? Also, should I use the fast or slow hardener?

Thank You!

Nice, that's pretty low readings. Sounds like you had a classic case of the gelcoat pox, with most of the moisture trapped between the gel and laminate. I don't know which meter you used, and they are all different, but anything below 10% relative on my scale is ready to coat. Many hulls never get that low without application of the Hotvac. You will have no problems down the road. The TSP washes really help.


Have you considered opening that rudder? Do you know how the armature is built? Sounds like its pretty wet. They almost always are.



I use Fast hardener. If you think about the method if application as I've described it, it makes sense because it allows you to stack on all the coats in one long day. I have used other hardeners in the past with short crew, often the thinking being that you can roll the coats of neat epoxy and then still catch the bond window for troweling filler coats the next morning. This doesn't usually work, as slow hardeners cure process tends to lead to much more blush, and by the time you've washed off the blush and dried it for coating you've lost the bond window, totally screwing yourself in the process.


Here's how it goes-


1. You come in early and 202 wipe the bare hull using the two rag technique. Then let it dry.

2. Apply the first coat of neat epoxy. This should take less than an hour.

3. Wait for it to tack off. In most conditions this will take about an hour. You want to be able to touch it gently with none coming off on your finger, but still leave a fingerprint.

4. Apply the second coat of neat epoxy with pigment of your choice to aid in coverage and fairing. Black works best.


5. It should now be close to noon. Go to lunch. Drink beer, eat food, etc. but don't miss your bond window! You will know approximately how long you have from the first wait.

6. Come back, set up, and apply the first slick of 407. Sometimes we do a mix of mostly 407 with a bit of 410 (25%?). This makes it sand easier. Don't use too much 410 or you'll have lots of pinholes. Mix like mayo, not peanut butter. This makes it easy to trowel nice and it will flow like paint. Also makes it much more water resistant.


7. Wait for bond window again.


8. Apply second slick and clean up.



If your crew is small, you can do this with two dedicated people. One mixer, one troweler. Just do one side of the boat each day. On day one stagger your neat epoxy layers onto the other side a few inches. On the morning of day two sand the overlap area along the centerline with a 60 grit DA real quick to prep it. Alcohol wipe first to remove blush, two ragging it.



Worst case scenario, if your slick comes out looking heinous, you soft pad it out without blowing through the neat layers and trowel it again. This has never happened to me, you'll be surprised how easy it is to slick well if you mix right. It's really all in the mix. Measure proportions for consistency. Pause to clean tools regularly. Don't try to do this if its really hot. Do the shady side in the morning, then the other side will be shady in afternoon. A single five gallon kit will do your bottom no problem, probably a bit less than a gallon per neat coat, similar amount for fill coats. You'll have plenty left to mix filler batches for more fills to build up the lows where you had to grind off the thick cracked gel.


This is not rocket science, you can do it. The rudder will be a real confidence booster. This method will give you the best bottom possible with today's materials. We have never had a warranty failure with this method. Feel free to ask any more questions. Think ahead and work smart!

[shamrock]

Hi Minaret,

So I have fixed the damage on my bottom and rudder and are getting ready to epoxy and barrier coat. I am down to bare fiberglass if you recall.

I don't know if I have it in me to trowel 407 and fair and I'm really happy with how fair the bottom is now anyway. I'm just not you!!!

My plan is to roll on two coats of fast 105 and then spray several coats of interprotect 2000e

Does it help to tip off the 105 to get it to level or smooth or should I not worry about that?

Also, with the Interprotect, should I apply it hot over the 105 to get a chemical bond or should I let the 105 cure and wash and sand then apply the barrier coat. I am also using coppoercoat antifouling and was wondering if it's possible to do it all in one day, 2 coats 105, 4-5 coats interprotect, then roll on 2 coats of coppercoat all chemical bonded. Will that work?

Thanks!!

Jay

[Chasing Summer]

http://www.yachtpaint.com/Literature...tb-usa-eng.pdf

You may find a lot of answers by reading this. The Interlux rep told me that since both 105 and Interlux 2000e are both epoxies I was basically wasteing both time and money. Multiple coats of 2000 will accomplish a propoer barrier coat.

This is where I am on my hull painting except I didn't do a peel. I will have to sand through much of the gelcoat to get rid of tiny blisters. I'm going to 2000e, then Awlfair LW, then many more coats of 2000e

Keep posting ... let us know how it's all going.

[shamrock]

Originally Posted by Chasing Summer

http://www.yachtpaint.com/Literature...tb-usa-eng.pdf

You may find a lot of answers by reading this. The Interlux rep told me that since both 105 and Interlux 2000e are both epoxies I was basically wasteing both time and money. Multiple coats of 2000 will accomplish a propoer barrier coat.

This is where I am on my hull painting except I didn't do a peel. I will have to sand through much of the gelcoat to get rid of tiny blisters. I'm going to 2000e, then Awlfair LW, then many more coats of 2000e

Keep posting ... let us know how it's all going.

Interlux recommends their own neat epoxy over bare fiberglass. I spoke to the rep today and actually just read that guide.

The 2000e is only designed to go over gelcoat not bare laminate. For blister repair, or total gelcoat removal, you must coat with epoxy. That's crazy we were told two different thing by the reps there. The manual reflects that as well, start with plain epoxy.

[Chasing Summer]

Shamrock ... Hmmmm ... huh ???? ... well, now I'm throughly confused ... some one with "know" needs to get the stories straight. We're just trying to get our boats painted so it doesn't all slide off a week after we put it back in the water.
Personally, (not and expert by any sence of the word here) epoxy is epoxy is epoxy ... at least I'm still above the waterline. I'm going to have to do more research.