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axkiker
07-13-2006, 05:08 AM
Hey I keep hearing that a complete re gel coat is very difficult to do on your own. Can someone fill me in why. I am a custom car painter and have recently done a few spot jobs on my boat with gel coat. Seems like really easy stuff to work with. I just sand , clean, spray then wet sand and buff. The stuff is 10 times easier to buff than clearcoat. I can see where the dry time makes things a little more difficult. Now I have not tried any big areas or hulls. So before I get into regelcoating the entire top half of my boat can someone fill me in on the specifics
thanks

EXTREMEBOATS
07-13-2006, 07:34 PM
Sounds like you can perform the operation... Its just more work then may want to do.Picture this....You block sand the whole boat and do repairs. Now you spray many coats of gel. And it looks like a "coble stone" street, now the work... You start blocking it down to a 1200 or even1500 grit, get your buffer out and polish it.... Here's a common prob, if you sand thru anywhere you start over or you will have a "Halo" arond the spot. I have only done a few in 20 years and "I" wont do another. Now I do regel the bottoms when I restore a boat. Then paint it the rest of the way up. Feel free to call if you want more "encouragement"
Mike

SmokinLowriderSS
07-14-2006, 02:38 AM
I just redid the gel on the bottom half of my Taylor SS
Purchased here:http://www.fibreglast.com/
Sand everything down (I went about 50 grit orbital), repair any damage/holes, whatever.
The layering goes as follows:
Color layer (or layers)
I sprayed red glitterflake so red glitter went in the clear layer over the top of the red layer.
Giltter sprayed in first clear layer.
spray 4 to 6 layers of clear.
Each layer needs to be .010 to .020" thick (a LOT thicker than paint).
Last layer needs to be sprayed with Styrene wax additive in the gel to fully harden it. From Fibreglast, the earlier layers (well, all the layers) are mixed 1:1 with a clear gloss additive which both thins the gell and allows it to partly harden in air.
Begin wet-sanding. I worked 220, 320, 400, 600, 800, 1000, 1500, 2000 grits before rubbing compound, then polishing compound. I used a B&D 1/3 sheet finish sander and a LOT of water in an old windex bottle.
I used a standard, ordinary suction gun, 1.8mm tip, and had zero trouble. Have LOTS of acetone handy, and DO NOT let the gell set up on you in tehe gun!

EXTREMEBOATS
07-14-2006, 11:45 PM
Man that makes me hurt.... reading your directions that is...LOL brought out the joyful memory of the last one I did. Not being a smart ass, I am only stressing the amount of work involved. When your done you'll understand. Its a good feeling!!! being done that is... Good luck man.... post pics as you go...
Mike

axkiker
08-04-2006, 05:39 AM
well heck looks like I may just paint the entire top half. I really didnt wanna be putting paint on top of gel but if thats the amount of work needed heck with all that.
thanks again

SmokinLowriderSS
08-04-2006, 03:54 PM
Just don't expect paint to take ANY kind of abrasive wear. IMRON might be slightly more UV stable to not yellow a bit, but it scratches EASY. Any sand in a shoe, on a foot, on a towel wiping water off the boat, etc. Anything bumps it, scrathes or marks it where gel has much more hard-surface resilience.

V1800J
08-24-2006, 06:26 AM
Smokin'
What size flake did you use on your hull. I'm trying to decide on whether to do it like you did it or put the flake on with the "flake buster" which is a device that blows dry flake onto wet clear and then you clear coat over that. Also, was you satisfied with your results.

SmokinLowriderSS
08-25-2006, 03:36 PM
.015” polyester flakes compatible with our #173 Gel Coat - From Fibreglast.
I had zero clog trouble with Fibreglast's stuff and a 1.8mm gun tip.
I set red flakes in clear, ovger a layer of red pigmented. Looks just like new.

victorfb
08-26-2006, 08:23 AM
i am in the process of re gel coating my 20' cruiser. it had the metal flake in all the graphics like the hockey sticks, on top the bubble, ect. i laminated 10 mil wood veneer in place of all the metal flake and glassed it all in. then i sprayed three differant colors of red 1/2" stipes surrounding all the wood inlay. a cool trick i found for getting nice thick and very clean lines to eachother was to use 20 mil plumbers tape. it has a thick striaght edge to build the gel real thick and clean so when you pull the tape and spray the next color, the two colors have a very clean parting line. just make sure to spray over the first color about a 1/16 or 1/8" then sand it down. youll be amazed on how clean the parting lines come out. i was. the rest is a white and instead of all the sanding and buffing, there is a very clear gel made by duratech. you sand the colors smooth with 400 and spray the clear. its self leveling and like paint, it dries shiney. in this clear will be a very fine mist of glass flake for that little sparkle look. i used the duratech in the bildge and sprayed it right over the sprayed white gel with red spakles with no sanding and it looks real nice. just some info for those that dont want to do all the sanding and polishing of traditional gel coating.
oh and with the plumbers tape deal, i cut the 2" wide rolls of tape in half with a band saw so i get twice as much. at 6 bucks a roll its a good idea. plus the tape is like electrical tape and extremely easy to make bends and such. just remember to use the factory edge if you try that trick.

flat broke
08-28-2006, 09:46 AM
Vic,
If you don't mind me askin, why didn't you try and mix the Duratec in with the gel instead of going base/clear? They make the additive which supposedly does the same thing. I'll be getting ready to shoot on mine in a couple weeks and I'd like to get some more info on this subject before I buy my gel.
I believe Wallygator used the Duratec mixed with gel, but I haven't seen him on the boards in a long time, and the last time I got a PM from him, he was finishing up re-doing the gel on his rig and would post pics when he was done.
Chris

victorfb
08-28-2006, 10:28 AM
chris, mixing the duratec in with the pigmented gel may give you a better shine than just straight gel, i dont know. havent tried that. basically though the clear duratech would just delute the pigmented gel a bit. by mixing the two you will still need to sand and buff. gel goes on with a rough texture. (orange peel effect). the duratec by itself is self leveling and dries to a very clear shine. spraying it over a smoothed out surface would give you a paint like clear coat effect with no sanding or buffing. also with the added clear coat i am able to give that very small sparkle effect by adding an extremely fine flake. (not metal flake) its a glass flake that is basically transperant untill the sun hits it just right. hense the sparkle. this can only be done with clear coats, adding it in the pigmented gel would not allow the flake to shine. too opaque. there are agents you can add to gel to thin it out a bit which will be easier to spray with a smoother outcome, but i havnt heard of an agent that allows the duratec to surface through the gel if mixed together. duratec is basically a very highley refined clear gel coat, so it would be a waste to mix it with your pigmented gel (IMHO). the professionals ive talked with seem very knowledgeable and i would think they would have told me about it if they had such a product. there is an agent that must be used for the final coat which is basically a wax to seal the gel so it can dry completely. gel will not harden completely if exposed to the air. (O2) by the way, i use the term "duratec" somewhat loosely. duratec is a company name and may in fact make a product that by adding to pigmented gel allows it to dry to a smooth shiney surface. i just havnt heard of it yet. if you have that info i would be very much interested in getting it from you if you dont mind. thanks. good luck with your project, id sure like to see it.

245 LIMITED
08-28-2006, 11:28 AM
i have been reading alot of the post reguarding re-paint useing gel. i have approx 12 years in auto car painting , so i have a slight idea. all of you seem very knowledgeable on this and its good to hear your " what works what dont"
my question is: i have a 25 ft chris craft 245 limited. very clean boat. i want to re-paint the sides and re gel the white top. over years you can see fading. i have tried to buff the sides but gave me a blotchy cloudy look , to a painters eye.. what products and brand names is best to use: ive seen lots but most are for large boats and appear to roll on like underside paint. where do you get the good stuff ? im in cal near lodi. any thing you gan give me hear tips on what grit to prep and final buff? thanks dudes

flat broke
08-28-2006, 12:04 PM
Vic, this is what I have from Duratec's site:
Duratec Polyester Clear Hi-Gloss Additive Product No.
904-001
Gelcoat Repair
Use Duratec Polyester Hi-Gloss Additive to repair clear or pigmented gelcoated FRP parts. The end result is a low porosity, smooth, high-gloss, hard surface that is similar in appearance to the original gelcoat surface. Duratec Polyester Clear Hi-Gloss Additive will reduce subsurface porosity and orange peel, increase impact resistance, improve gloss retention and heat distortion temperatures.
Application Conditions
The surface should be clean, dry and free from oil, grease, wax or other contaminants. Ambient temperature should be in excess of 60F 16°C to ensure a rapid and complete cure. Time calculations are based on temperatures of 77°F, 25°C.
Surface and Product Preparation
Thoroughly sand the area to be repaired to a 80-180 grit finish.
Blend and mix completely equal parts of Duratec Polyester Clear Hi-Gloss Additive and the gelcoat required for the repair or overspray. Catalyze at 2 percent with mekP catalyst (20 cc per quart). Thin 5-10 percent if necessary to a desired spray viscosity with Duratec Lacquer Thinner 39LAC-1.
Application Procedure
Note: Spray pressures should be 35-50 psi. If a pressure pot is used, provide 10-15 psi pot pressure.
Spray the entire surface to be repaired with a fine mist coat and wait 2 minutes for the solvents to flash off. Follow with wet coats, overlapping the surrounding area to ensure complete coverage.
Note: Do not inhibit the cure by adding wax surfacing agents. The combined gelcoat and Duratec polyester Clear Hi-Gloss Additive will air cure to a hard, glossy finish in approximately 1-2 hours. (Apply forced-air heat for a 30-minute cure time.)
Lightly sand the repaired area with 320-800 grit sandpaper, either wet or dry, and buff to the desired finish, ensuring that the newly gelcoated area is blended with the surrounding gelcoat surface. Use Aqua-Buff 1000-W Fast Cut Compound and Aqua-Buff 2000 Compound/Polish to achieve swirl mark-free finish.
SAFETY PRECAUTIONS: Duratec Polyester Clear Hi-Gloss Additive is extremely flammable. Do not apply near sparks, open flame or heat. Keep area ventilated. Do not smoke. Avoid continuous breathing of vapor. Do not take internally.
http://www.duratec1.com/ag07.html
Mexrunner here on the boards used something similar and mentioned that you didnt need to use PVA to seal te job. I've been asking questions on this stuff for a while, but have yet to see a boat done w/the additive
BTW Duratec makes a top coat and the additive version and has the spec on their page. Either way I don't think it would have worked for you, since you needed a clear coat to suspend the glass flake in.
Chris

victorfb
08-29-2006, 08:44 AM
Lightly sand the repaired area with 320-800 grit sandpaper, either wet or dry, and buff to the desired finish, ensuring that the newly gelcoated area is blended with the surrounding gelcoat surface. Use Aqua-Buff 1000-W Fast Cut Compound and Aqua-Buff 2000 Compound/Polish to achieve swirl mark-free finish.
Chris
thanks chris, thats probably a good product for what you are doing on your project. i am useing the 904-045. as you mentioned i need a clear finish coat to suspend the flake. the 904-001 seems to be more of an addative to help keep the sanding process to a minimum, but from what i understand you still need to sand and buff. i would definatly talk with wallygator to see if he thought the addative is a big plus. that stuff isnt cheap, but im betting its worth the high price tag. in my case i needed a clear coat to cover the wood inlay aswell, so i went the top coat route. the colors have been sprayed on the bottom and im hoping to spray the clear this afternoon, so ill let you know how it works out. it definatly looked real good in the motor well when i sprayed it right over the unsanded white gel. keeping my fingers crossed. thanks again for the info on the duratec addative though. i may try that on the next project that doesnt require the clear finish coat.

V1800J
08-29-2006, 11:04 AM
Smokin'
Was your red base coat, white gel coat that was tinted? In other words, how did you color match the red base coat to match the top half? Also, how much material was needed for your hull?

victorfb
08-29-2006, 02:40 PM
i know you werent asking me but i thought id just add this. you need to start with either a clear or regular base coat gel to add pigment. dont use white (unless thats the color your looking for). adding red pigment to white will give you pink. and you dont want to add much pigment either, pigments are not a product that actually hardens, it just colors, so the more pigment you add the weaker the gel. hope you dont mind me butting in.

SmokinLowriderSS
08-29-2006, 06:42 PM
Like victor said, if you tint white with the pigments, you get pastells. I made red per the instructions by tinting red in clear gel, atop which I sprayed the red flakes in untinted clear gel. If I recall correctly, a gallon of gel covers something like 110 sq ft to .010", which is pretty damn close to the surface area of the hull of an 18' v-hull boat. Between all the layers, I blew 4 gallons of gel along with 4 gallons of clear gloss additive, and about a 1/4 cup of styrene way (last layer), all a 1qt siphon gun load at a time. 8 gal of material.

victorfb
08-29-2006, 07:09 PM
if your fast enough i hear you can use a pressure pot, but i wouldnt try it. i am slower than shiat. i also seem to be wasting a bit of material as the project goes on, but thats normal im sure. one life saver for me was to use a devilbis gravity feed gun with the bag inserts. ALOT less cleanup between coats. pull the bag, clean the gun and tip, and move on. im still going through quite a bit of acetone though. i cant think to wonder if the local home depot thinks ive got a meth lab going.

flat broke
08-30-2006, 06:33 AM
Vic,
FourQ was using the clear coat like you are and had great results on the small stuff he was doing. It looked like he'd just need to block it with 1000 or so then buff. If you can, shoot some before/after pictures of the clear process. Some pics of the the last coat of gel before sanding, after sanding, after the top coat, and then after the top coat sanded or buffed.
Actually, I'd be okay with the thought of doing the topcoat on the top of my boat where I want to do a color change. I'll probably do the additive on the bottom where I'm not gunning for max shine anyhow. The only thing that scares me away from the topcoat a little would be longevity. I keep hearing of clears failing after a couple of years. I know there are exceptions, but I have to store my boat outside for the time being, so I don't want to be looking at this type of project again in a couple of years.
Talk to you later,
Chris

V1800J
08-31-2006, 06:37 AM
Smokin'
How did you figure the amount of metal flake? Is it trial and error. On bass boats for example it looks really dense, whereas on my 1975 baja it looks slightly more spread out where the base coat is a little more visable.

SmokinLowriderSS
08-31-2006, 04:49 PM
Trial and error, or more precisely, guess and hope.LOL. It came out really nice IMO, looks just like the top (orriginal). If memory serves right, I used about 2 oz in a 2-qt mix of gel/clear gloss additive. There are mix ammount advice on fibreglast's website.
Here, from fibreglast:
The glitterflake coat should be applied directly behind the cover coat. Normally,
glitterflake is added at 10% by weight , but this may be increased to up to 20%. In excess of 20% can cause curing problems including a distortion or ripple in the surface. Also, mixing the glitterflake with the gel coat should not be done more than one hour before it is to be applied.
Catalylze the glitterflake gel coat at the recommended level and apply a wet layer of up to 10-20 mils.
The glitterflake layer will not provide a total hide and some visible changes in the orientation of the flakes will be present. We recommend using a pigmented layer directly behind the glitterflake layer which will hide the reinforcement and offer an improved final appearance. Typically, a contrasting pigment

martan
10-07-2006, 11:55 PM
I've done a lot of it and it is definitely not as easy as paint. I'm wondering what kind of clear you are using? I would much rather buff clear than gel. That being said I plan to gel the hull on my own boat in the next year or so. Gel coat has come a long way in the last 5 years.
I've seen several people mention they have re gelled entire bottoms, and I wonder do any of these boats get left in the water all season? I've seen a lot of boats that can sit in the water all season and never blister. Patch gel on the bottom doesn't usually do so good.
Some pictures of a brand new Mastercraft on there that I had to re gel this last month. www.bowkersfiberglass.com/class_war.htm

SmokinLowriderSS
10-08-2006, 06:36 AM
The clear gel I used was the same clear gel, all the way through, color and glitterflake layers, from Fibreglast, part number 173 mixed 1:1 volume with p/n 1040 clear gloss additive. #71 styrene wax was mixed into final top layer to fully harden the entire stack.
http://www.fibreglast.com/showproducts-category-Gel%20Coats%20&%20Hardener-10.html
#173 is our highest quality gel coat. It is fully UV resistant so it may be used as a protective clear coat over other colors or glitterflake. Very true color reproduction can be achieved when mixing with all our color pigments. Blend with Hi-Gloss Additive when top coating. Requires 2% MEKP. (which comes with it)
#1040 can be mixed 1:1 with regular gel coat to reduce viscosity, porosity, and permit a complete open air cure. The reduction in viscosity allows gel coat to be sprayed controllably through siphon and HVLP equipment, reducing sanding and polishing time. Below the waterline repairs still need the addition of #71 Styrene Wax for maximum hardness.
Requires 2% MEKP.

axkiker
10-25-2006, 05:08 AM
OMG im dizzy now. I thought auto paint was a pain. Jesus this is crazy. I have spent years trying to keep wax and oil out/off of my painted surfaces now they are saying you have to add in parifin wax to make it cure. WTF.
I just wanna cover up my ugly pink stripe. LOL

Nucking futs
10-25-2006, 07:09 AM
Just make sure the gell coat is tacked before you add the pva or the gell will start to cure with the pva and you will see a fine haze or a inlaid orange peel that will not sand out and you will sand through and have to do a patch job. Ask me how I know.. lol.
Im getting ready to do my floor and the top side again, but im going sintech in place of the duratec. The sintech thins out better and is a way better gloss look with alot less work after your done spraying.

martan
10-26-2006, 06:09 AM
Has anyone left a boat in the water for a season after spraying the bottom with gel coat?
www.bowkersfiberglass.com

DaveA
11-04-2006, 08:57 AM
Has anyone left a boat in the water for a season after spraying the bottom with gel coat?
Neighbor did. Not a pretty sight, all the blistering that occurred. Boat shop told him to keep it on the trailer whenever possible, but his kids didn't listen.
Looks like you guys do nice work. I was interested in the Elite- was that the entire core that came out of that bottom in one piece?? Quite a job!
Question- how difficult is it to match 1970's era gelcoat (yellow, fer instance) that was formulated using cadmium and other components that are not allowed today? The original manufacturer of the gel said that once they weren't allowed to use those components, they chucked the formula and mixed up something else (that's similar but no match) to sell to the boat shops. Besides, they're a division of Valspar now, and all those old formulas were lost anyway. What do you think?
DaveA

DUCKY
11-05-2006, 10:01 PM
It's a bitch to say the least. Utilizing neutral base and raw pigments I am able to do a quite reasonable job on the old boats, but it's time consuming. And yellow, is one of the toughest colors to blend to begin with. Just like automotive paint, there is no such thing as pouring gel out of the can and spraying it without tinting the color. Anyone that says they do is either a fool, or does poor quality work.

DUCKY
11-05-2006, 10:06 PM
The clear gel I used was the same clear gel, all the way through, color and glitterflake layers, #71 styrene wax was mixed into final top layer to fully harden the entire stack.
Wow, you put wax in your clear? Good thing it's on the bottom, because if it were exposed to the sun your red metal flake would be little more than a milky haze in no time....

SmokinLowriderSS
11-06-2006, 05:34 AM
Wow, you put wax in your clear? Good thing it's on the bottom, because if it were exposed to the sun your red metal flake would be little more than a milky haze in no time....
You're misunderstanding the substance DUCKY.
The styrene wax has to be in gel on an exterior repair. It separates from the gel, and surfaces, where it films, sealing air off of the gel surface, which promotes the final hard cure of the gel, otherwise, even catalyzed gel does not cure properly exposed to air.
It's not an issue in a mold, as the mold is the surface sealer, and the following layers of gel seal the previous ones, then the glass resin seals it all.
The final sanding takes the styrene off the surface. You can buy, pre-waxed gel, if the outside job in large enough. You can even wax each layer, to harden each one fully, BUT, the next layer wil not stick and the wax must be sanded off, this time between layers.
It was mixed on the sides too, and looks just fine, after a lot of sun-time last summer, it's not car wax.
From Fibreglast's website:
# 71 Styrene Wax is a 5% solution of paraffin dissolved in styrene that may be added to non waxed polyester resins and gel coats to prevent the prolonged tackiness associated with thin sections of polyesters. If the resin contains paraffins, the wax will rise to the surface and protect the curing resin from the inhibiting action of the air. However, if the resin is allowed to fully cure, the paraffins on the surface will prevent adhesion of further coats of resin and must be sanded off prior to additional applications. We recommend adding #71 at 5% for thin coatings. Use with #1040 Hi-Gloss Additive when performing repairs below the water line.

SmokinLowriderSS
11-06-2006, 05:35 AM
Has anyone left a boat in the water for a season after spraying the bottom with gel coat?
www.bowkersfiberglass.com
Not all season, as I don't live at or store Lowrider at the lake. 4 or 5 days has been done, on repeat occasions, with no harm.

DUCKY
11-06-2006, 08:41 AM
You're misunderstanding the substance DUCKY.
I can assure you that I didn't misunderstand. I know what "styrene/wax" is and I know it's applications and limitations. I use it on a daily basis about 9mos out of the year on solid color repairs. In the winter and on cleared repairs I use PVA. I would use it year round, but the surfacing agent is damn near hardened in the can when the temp drops below 60 degrees. Regardless of what "fiberglast's" website says, it is nearly a cardinal sin to add surfacing agent to clear gelcoat in a repair situation. Most of the paraffin wax does float to the top and seal out the air for a better cure, but rest assured that you did not sand it all off. You probably got lucky due to the fact you did the whole bottom and whole sides, but if you simply did a repair on an otherwise perfect boat and mixed in surfacing agent, you would have a cloudy spot that you cannot get rid of without re-spraying. It is not logical to actually beleive that something you mixed in your material will completely disappear.

SmokinLowriderSS
11-06-2006, 04:58 PM
Duly noted, and understood. I'll keep the PVA in mind in a number of years when I do eventually redo the top. Thx DUCKY.