Re gelcoating my bayliner 2252

[DeepBlue2010]

Hi everyone,
My hull sides (under the rub rail and above the deep V) is in horrible shape and I don?t know what to do. I was trying to fix few digs and scratches with a gelcoat repair kit and the process turned into a nightmare. When I was trying to sand the past, some areas started to thin to the point that I can almost see the raw fiber behind and some areas actually did show it. I used a sand block for wet sanding and I didn?t apply any uneven pressure ? not that I am aware of anyway ? so I don?t know what the real reason for this problem is. However, I need to fix it now. What kind of preparation I need to do before shooting the new gelcoat? Should I sand and fair the whole hull (I mean the sides) or the new gelcoat will take care of the sanding marks and scratches that still showing. Some people said I need to get the hull silky smooth before shooting and even buff with heavy duty 3M compound. Others said NO, just sand the whole thing with 220 wet - just to get t rough for the new GC - and shoot over that. The current status of the hull is sanding scratch marks that 3M heavy duty compound was not able to remove and some oxidization here and there. Given that, what is the right course of action? Your help is greatly appreciated.

 

[ondarvr]

Re: Re gelcoating my bayliner 2252

First off, if you had problems using a gel coat patch kit, multiply that by 1000 and you'll get closer to what the hassle will be in re-gel coating the entire hull. Not that you can't do it, just that its a great deal of work.

Read this first.


http://forums.iboats.com/showthread.php?t=234392

 

[DeepBlue2010]

Re: Re gelcoating my bayliner 2252

You are right, I think I screwed up. Even if the hull was uneven from 15 years of compounding and maintenance, I was supposed to factor this in. Even though I still have strong feeling about doing it myself, I got a quote from a dealer to spray all the thinned out areas only; but some items I just can?t wrap my head around. For example, 10 hours buffing?!? Is this required before or after spraying? Can I do it myself after I get her back? No matter who will do it, I still need to understand the steps involved and the order of them so I don?t feel like I am being taken for a ride and I can also decide what can I do myself to save some $$, I just happen to have some time on my hand these days I would like to use.
I read some pages - relevant to gelcoating - in the post you referred me to. It is very long thread indeed and I will continue reading. My first impression is that it is not the same situation. He was building from scratch not fixing a defect and as a result, most of my questions will not be answered there. My gelcoat is already there and in a good shape in most parts. I have some areas started to thin and only one area ? the worst ? is down to fiberglass. Based in this condition, would you be kind enough to summarize the steps required for the repair in your opinion? I learned from the post you referred me to that you are the subject expert and I am desperate for an expert advice. Is what this dealer suggested to spray only the thin areas is the right solution for this situation? If so, do they really need to buff for 10 hours? If I want to take a stab at it myself, do I use the same method or spray the whole sides. If so, do I need to sand before? I was told that spraying over the good areas of the hull will result in areas that are thick with GC - over 40 mils ? and this will make it subject to spider cracks in the future, and I MUST sand the whole thing down to fiberglass before spraying to get an even coverage, is this true?

Here are some pictures

very thin, scratches
http://forums.iboats.com/attachment.php?attachmentid=66425&d=1283528578

Thin
http://forums.iboats.com/attachment.php?attachmentid=66426&d=1283528609

The worst I have
http://forums.iboats.com/attachment.php?attachmentid=66427&d=1283528646

 

[ondarvr]

Re: Re gelcoating my bayliner 2252

In the first post you implied you were respraying the whole hull,

"What kind of preparation I need to do before shooting the new gelcoat? Should I sand and fair the whole hull (I mean the sides) or the new gelcoat will take care of the sanding marks and scratches that still showing."

That's why I linked that thread, it covers the hassles of respraying the entire hull.

Just respraying the bads spots is a little different.

The problem with working on old gel coat is you never know exactly what you're dealing with, or if the attempts to do minor repairs will end up looking worse than what was there to start with.

Old gel coat will be faded and discolored, so matching what you have on there now will not really be possible, even if they're close at first the repairs will fade to be a different color in a year or so.

Do a search here on gel coat repairs and you'll have a great deal to read, this will give you a better understanding of what needs to be done.

 

[DeepBlue2010]

Re: Re gelcoating my bayliner 2252

How helpful. You took the time to write few lines asking me to do a research but answer none of my questions. You could have spent the same amount of time guide me to the right choice or answering any of my questions. Well, I did do the research and couldn?t find two opinions alike. If you come to me asking for HELP solving a quadratic deferential equation, for instance, how would you feel if I ? helpfully enough ? brushed you off and said, oh well, read the math literature, it is right there, piece of cake. I was told that this forum is helpful and questions are answered faster than they were asked. Not my experience so far. Thanks anyway.

 

[ondarvr]

Re: Re gelcoating my bayliner 2252

Sorry if you took it the wrong way, but if I asked you for help on a "quadratic deferential equation" I would need to know what one was first.

I said to read a few different posts because I could spend all day typing a reply that's been typed fifty times before and it may not be the information you needed because without a little more information on the subject you may not know what to ask about. Or I could ask you to do a little background work on your own for you to better understand what it is you want to do, which may narrow down the line of questions and get you better answers.

 

[DeepBlue2010]

Re: Re gelcoating my bayliner 2252

I did narrow down my question to the few I asked already. My situation is not that common which makes the reading and reading and more reading simply pointless. I need an expert advice tailored to my situation. I posted my questions with pictures to give whoever is willing to help as much info as they possibly may need to give a well informed feedback. Looking at these picture, here are my questions, again..
Is what the dealer suggested ? spray only the thin areas ? can be considered the best course of action in this situation. Can it be done and look flawless at the end or it will still show differences and he will end up telling me ?this is the best we can do for one grand??
If I decide to do it myself and spray the two sides ? not the whole thing just the sides under the rub rail and above the bottom V ? do I need to sand to bare fiberglass to guarantee even coating?
If No, what kind of preparation work I need before spraying. I am no stranger to spraying but never GC.

 

[dlngr]

Re: Re gelcoating my bayliner 2252

Well,Deep,guess I might not be much help either,but my suggestion is to find a body and paint shop that will take you on as an apprentice.After about 18 months,you should be able to do the job yourself,and you won't have to do any more reading.

 

[ondarvr]

Re: Re gelcoating my bayliner 2252

If I was asking about a quadratic deferential equation and stumbling over simple addition and subtraction would you want to start with basic math and then walk me through the entire process of advancing to a complete understanding of the subject and then possibly find out I didn't really need to know anything about it because I was just wanting to figure out the MPG on my mini van.

I answered your first question on how well it will look (and hold up) if they just do spot repairs.

"The problem with working on old gel coat is you never know exactly what you're dealing with, or if the attempts to do minor repairs will end up looking worse than what was there to start with.

Old gel coat will be faded and discolored, so matching what you have on there now will not really be possible, even if they're close at first the repairs will fade to be a different color in a year or so."


The thread I linked goes into great detail on re-gel coating an entire hull. You will see I told him not to grind off all of the gel coat, along with other tips, plus what his experience was like.

You haven't asked about painting it, but if you read some of the threads on the gel coat subject you would get some ideas and opinions on that too.

 

[Yacht Dr.]

Re: Re gelcoating my bayliner 2252

Hello Deep..and Welcome to Iboats...

Gel is not that hard to do.. and I do recommend that for a Full Respray..

Its not that hard at all ..

1. Wash boat.. Clean.. mebbe with Vinigar wash..
2. sand with 80 grit ( gel bites to up to 180 quite well.. 320 if you have blend spots )
3. acetone with rags..again..and again....
4. depending on you location..
5. Gel can be reduced for Topcoat with proper agents.. ( Ive done gel/acetone and gel/"patchaid" for full sprays.)
6. I recommend spray over after gel time with PVA for large areas..
7. guide coat with Dykem or Black marker b4 sanding to help with your sanding.
8. sand up to 1000 and buff ( dont sand all of your guide coat off with 320 or 400 .. just be patient..
9. buff and buff.. you may have to sand here and there..but it will be a mirror..

I have done plenty of 20 footers .. Sand and spray one day..sand and buff the next..

Quality gel is what you want..If not..your going to spend 1 gallon of acetone and 5 LBs of rags to remove the precure gel first.

YD.

PS. IF you use PVA .. the wash with water Before you sand..

 

[DeepBlue2010]

Re: Re gelcoating my bayliner 2252

@ dlngr , It took me 18 month to get my MBA. I refuse to believe that this process takes the same amount of time to master even with an average IQ person. Thanks for your advice but no thanks.

@ ondarvr, Unfortunately I am not getting any help from you and I am not a big fan of arguing for the heck of it. If you were willing to help you would have done it already. I am no stranger to spraying, I am a damn good wood worker, it is a hobby of mine. I didn?t ask about basics of spraying and all of the 101 thinning, waxing, etc. I asked very specific questions related to my specific situation. You want to play Mr. few words, go research, gelcoat hot shot?! Fine, let?s leave it at that then.

@ Yacht Dr , Thanks for the welcome and for your help. Did you mean I need to sand the whole old gelcoat down or just the affected areas?

 

[Yacht Dr.]

Re: Re gelcoating my bayliner 2252

Hello Deep..

Wherever you want to spray your gel MUST be prepped/sanded.

Sand with 80 or 120. No wetsanding involved for gel prep.

You dont need to sand it All Off..just make sure the shine is gone.

Id use a 6" D/A sander with some 80 grit for the bulk of the job..then hand sand your edges etc.

YD.

PS. you can scribble the heck out of your surface with a pencil to kinda help you see were your done sanding ( I use blue Dykem thinned with acetone for my sanding guide ).

 

[DeepBlue2010]

Re: Re gelcoating my bayliner 2252

Thanks. I appreciate your help.

 

[Tail_Gunner]

Re: Re gelcoating my bayliner 2252

Greets Deep Blue....It seems i was in your position 4 yrs ago...What do you do how do you it..

1.Wash the boat with xylene twice maybe three times
2. Take a 200 grit sand paper place it on a sanding sponge and sand off all the oxidated gel...the outer surface not all of it
3. Fill any Irregularitys with a fairing compund...Guess what sand again...to a flat mirror finish
4. Paint the boat with a two part urethane...Make it simple Interlux Perfection..
5. If you do the above and when you done fairing and sanding post back

The above is a bit sharp angled...But gel coating was never meant to applied like paint...Can it be done yes ...but it takes a great deal of experince..the right eqipment...and money..Ohh and a great deal of sanding..

Honestly you will spend 95% of your time fairing and sanding...5% painting The painting will cost you less in both money and time...

As to Ondarvr....place close attention when he has something to say....He is perhaps one of the most knowledgeable persons in the indrusty and his advice and time is for free here @ I-boats..

Just a thought take for what it is..

 

[Yacht Dr.]

Re: Re gelcoating my bayliner 2252

Hello again deep..

I will only say that Whatever patch you want to do ( expert or self ..buying factory gel ) Will eventually show..

So if your worried about your " patch gel/paint " not to ever show again..worry some more.. you WILL have that patch forever. It will fade ( as Ond said ) to a different color..

There is only one option for this " I dont want patches on my boat showing up sometime in the future " .. thats a Full Respray..

Gel or Prime/Paint.. your choice.. there are pros and cons with each.

YD.

PS. Sometimes the help comes across rather distant from your question ( Ive done this many times ). Be gentile please.. these guys have shown in the past that They know "things" .. albiet not your answers Right now..but they still show up while others might just leave you dry. .. If you get what im saying...

 

[DeepBlue2010]

Re: Re gelcoating my bayliner 2252

Gunner, Ondarvr experience is not questionable specially by a beginner like myself. It is the style that got us started on the wrong foot. This dealer was rushing me to make a decision before his GC guy leaves for a long vacation so I needed fast answer not the bible.

YD, It wasn?t my intention to be rough or rude to anyone and I do get your drift about the helpful ? although not what you are looking for ? answers. But asking me to go mine the hidden wisdom out of 162 pages thread with 4050 posts to be able to determine the ROI of investing between $1K and $2K in a patch job is kind of pushing it, don?t you think. And then using my analogy to say I don?t know what gelcoat is!! ? If I were to ask you about ?.. I would have to know what one is first?. I didn?t ask what gelcoat is because I researched the hell out of the subject to understand this specific finish and the difference between it and the type of finishes I am used to spraying. The only missing information was preparation work and expert advice on the potential success of a patch job. I thought I was really specific, maybe not.
Anyway, I have decided to spray the two sides of my hull from the rub rail down to above the bottom. I will be doing this myself. From this forum and others, I collected almost everything I need but I still have some questions..
I read that any build up of gelcoat above 35mils (before sanding, compounding and polishing) will lead to overall thickness greater than 25 mils after sanding and polishing and this will lead to spider cracks in the future. The problem is, the sides are not even. Some areas look good ? even though I can?t quantify this good condition - and some spots are really thin. So, If I am shooting 30 mils (3 coats 10 mils each) and after sanding and compounding, for sure I will end up with thicker areas than 25 mils. By experience, is this true problem or I am over thinking this? And if it is a problem, what is the solution for it, sanding the old gelcoat down?
2) Any recommendation for a good quality GC? I am comparing between Evercoat & USComposites. Any experienced advice?
3) I will build a mockup for practicing before spraying my boat. It is made out of plywood and resembles one hull side, what kind of surface preparation work I need to do before spraying the wood in terms of sanding, priming, etc.
4) At least one area in the hull, see pictures, are down to bare fiberglass; do I need to prime or I can spray over it without any primer. From what I read so far, I think it is ok to just spray without any primer but I want to make sure.

Thanks in advance

 

[Yacht Dr.]

Re: Re gelcoating my bayliner 2252

Hello Deep..

Your overthinking it..

Try using cardboard for your spray tests ..

You just need to prep/sand ( 80 grittish ) then spray gel. No primer is needed.

YD.

 

[Tail_Gunner]

Re: Re gelcoating my bayliner 2252

Ok some very basic stuff...In all types of spray application's controling the amount of product..(flow rate) and uniformly laying down the product on the hull determines the final outcome...And that takes time and experience with the type of gun you are using...Aka airless sprayer...pot type whatever... and then there is the tips you are going to use....One may have a 10 inch fan another is 8 or 6...and its obvious the smaller fan at a given pressure is going to lay down more product...So you have to learn how fast to move the gun using a say a 8 inch fan...now with that in mind gel is much heavier than paint..it lays down thicker... it has a much higher build...Keep that in mind...

Heres the secret...You have to master laying down a fairly straight line say 5' you then reverse back at the same rate of speed laying down a new line..THis must be done with extreme precsion or you will get overlap from one line to another..Overlap said simlpy is you will have lines that have twice as much product going down the boat...and gel does not flow like paint..it wont level the same and when she drys yes you will have to sand of smooth out those line....Hmm sanding

Now again unlike paint you have a pot time...of what 10-15 mins..That is the gel is going to setup..harden...So you have to map out what your going to do in one shot or pot....calmly laying down product uniformly with no or minute overlap and timing yourself all the way thourgh it..then clean out the gun...pot...and lines..or you may ruin your equipment

So you simply make a sprayer selection...tip selection learn how to lay down the product and a given rate of speed all the while keeping a keen eye of overlap or flashing knowing you have about 10 minutes to shoot the boat then you clean the lines and the gun and poof your done....

Theres a product out there called duratec good stuff it does aid in flow.Highly recomended...and lots of sand paper..

http://www.duratec1.com/dp07.html

http://www.fibreglast.com/product/LC_005

I wish you the best of luck....Take your time it can be done

 

[Yacht Dr.]

Re: Re gelcoating my bayliner 2252

Hello Again..

TG...no Disrespect here..but

"So you simply make a sprayer selection...tip selection learn how to lay down the product and a given rate of speed all the while keeping a keen eye of overlap or flashing knowing you have about 10 minutes to shoot the boat then you clean the lines and the gun and poof your done....?

Have you ever full sprayed a geljob boat before ??

The last deck I sprayed took 4 hours..

Yes you have to be careful of pot life and cureing in guns/lines and such..

That is what Reduction is for.. pot life. You have Way more then 10 min to apply gel ( 3-4 coats is recommended ) .. talk to Composits one.

however.. the more you reduce your top/gel is going to make that surface agent evaporate ( have washed down a few boats with acetone and rags after a full spray to get to cured gel ).

PVA is your best bet with any thinned gel.. apply when starting to get tacky..but dont spray with high pressure thereby blowing air into the topcoat/gel.

Ive used 5 gallon pressure pots with 25' hose to apply gel..never got stuck with kicking gel.

You have to know how to do gel..thats why its becoming a lost art..everyone is Afraid of IT. And for no reason lol...Its ez ( large tip gun right from harborF. will do the trick ).

YD.

 

[Tail_Gunner]

Re: Re gelcoating my bayliner 2252

Yes...Once your prepped and taped off how in gods name could you take 4 hours....Well i did not use a binks style sprayer..(used a airless) it was just that simple..I used a tip that gave me about a 6" fan and shot the hull in about 10 minutes..Now a deck with all off its angles would be as simple to map out how i would lay it down..I would think on a 20' boat i would shoot the length of the top rail using a very small tip in one continus shot...immeditaly go back and do the sides what another 10 minute shot..

I will saying my spraying experience does not come automotive nor marine. We shot custom cabinets in residental housing varnishes and laquers..Gel coat is very much like a hot varnish in my experience...As to cleaning the lines in a airless sprayer yes it pot time is critical i was not about to keep any product in the line of pump for more than 10 minutes

http://www.fibreglast.com/product/LC_005



Product PropertiesViscosity - As measured on a Brookfield Viscometer Model RVF, Spindle #2 at 2.0 rpm.110 CPSThixotropic Index 1Gel Time - Sample based on a 100 g mass, catalyzed at 2 percent with MEKP...16-20 min.Weight per Gallon8.0 lbsVolatile Organic Compounds198 g/l