ChattanoogaJSB

Thank you Russ, I will definitely look into it for when that time comes.

DUB

What amazes me is how some people can write that polyester gelcoat does NOT have any strength qualities of its own...and with that comment I can understand why it is not being used with that mentality...obviously some people have not used it and understood how it works and what you a have to do to make it be successful...which is NOT rocket since.....but to some people..it may just seem that way....and some people choose the 'easier way out'...which is 'their way' ....and if it works for THEM...GREAT!!!

MY WAY of doing things is just that...it is MY WAY. For those who may not know....Understand that I do this for a living and I do not have the time to re-work jobs due to material/procedure failure ...or failures that occur after the Corvette has been delivered. AND I am NOT writing that MY situation is any better than any DIY'ers situation. Re-working failed issues SUCKS...and costs money and time....BUT I do a lot of Corvettes...and not just one every once and a while. Any failure SUCKS...regardless...which is why I try to help those who ask for help and relay real world experiences. AND I have honed my procedures and the materials I use so that potential issues that arise is almost ZERO. I can not write ZERO...because...if I do... that is opening up a door for 'Murphy's Law' to get into. And I understand that many people have their strong beliefs in this and many subjects...and they are entitled to have them....and even share any experiences....BUT I am here to squash them so people who read this post understand that gelcoat is NOT a product that ALWAYS fails....because if it did...then why is it still being used with great success.

And as for gelcoat being brittle. Polyester fiberglass resin manufactured parts CRACK...and that is a fact. PAINT CRACKS....so what is the point. This comment is pointless. Like this is supposed to reinforce that gelcoat is not worthy of using....but some of these same people will buy an aftermarket parts that is hand-laid with gelcoat on it....and that is just fine....YEAH----RIGHT! ONLY until GM started using SMC did I see that the body material could take a little bit more flexing before any serious cracks developed...and when SMC cracks...it does not crack like the press-molded fiberglass panels.

The benefit of what the gelcoat is providing can not be EQUALLY compared to any other product. The only one that even comes close to gelcoat is a polyester primer....and that is it.

If a person chooses to use any product of their choice and get it to work and they are happy with it...I am TRULY fine with that. I cannot endorse some of it ...only beacsue if I have used it CORRECTLY and it failed...and I often times do tests on scrap panels and see what happens. So these comments are not just because it happen ONCE.

AND lastly...I can not grasp the concept in washing a bare fiberglass Corvette that has filler on it with DAWN with WATER. I know it has been done with success...but I do not have days on end to allow the body to dry out....and possibly leaving residue of a foreign material that can inhibit adhesion. BUT...to each his/her own. I go a different route that does not stop my process...and that begins with the environment I do my body work in is not having someone beside it spraying WD-40.

For the record. 'porchdog' here on the Forum, I would say is an expert in the SPI products. He probably has more 'tricks of his sleeve' when using these products than anyone I can think of. I would have to advise anyone who wants to know the 'in's and outs' of the products they offer...contact him. I KNOW I WOULD if I were to begin using SPI products.

AND YES...PPG epoxy primer is NOT designed to be sanded. I only use it on steel parts that do not require sanding....or in areas that will never see the sun.

DUB

MrPbody

Calm down Dub. you're gona have a stroke if you keep it up.

Russ

DUB

Russ..

and thanks for the concern....something SERIOUSLY to consider.... but being is normal for me working on these Corvettes all the time. If I calmed down...I think the pressure would build up and I would explode.


DUB

67vetteal

I am grateful to each and every person who takes the time to share his wisdom with everyone else on this Board. I've been working on these cars from way before the Terms C-1, C-2 etc. ever were. I'm able to go out to the garage and perform any task that is present. BUT, don't ask me to write it down clearly for someone less experienced to understand the proper way to do something. So Thanks so much to all the "Pro" guys around here who take the time to let us know their opinions and experiences. Al W.

TCracingCA

PS I haven't grabbed any of the PPG brands myself, but just because the two local paint supply outfits I use are connected up with other manufacturers. I know the Auto Industry is big on PPG!

Also it sounds like your prep is given extra effort, with hand blocking and such. Over 2k with heavy blocking, I find I can thinner wipe and tack cloth and still come away with sanding residue, so I just lay down an extra careful last coating and to check the smoothness and to ensure I have no issues lingering from the sanding. I have been a fan of the epoxy primers under and over body fillers and such, because it will prevent bleed thru to the car bodies or paint.

I will keep reading the rest of the post now! And PS on my metal body cars, I am more onboard with the epoxy primers and body fillers and 2K products, but on the Corvettes or surfboards, I will still be using Gelcoats.

TCracingCA

I have learned from you on some things. Thank you!

64Corvette

DUB has said everything better that I could say it, but I would liked to add couple of thoughts. I would like to reiterate longevity. This car was painted in 2002 and believe me when I tell you this car was not virgin fiberglass! It was gel coated in 2000. In 2000 I could buy a gallon of gel coat from the boat repair shops for 20.00, cheaper than primer surfacer. You would never know what was below the color of this car if I had not told you. I put on 4 coats of gel coat and blocked it till I could start seeing the repaired areas. I re- gel coated and blocked it again, then I used automotive prime surfacer for final sanding. It was then sealed and top coated. If painting a mid year I would not paint it if I could not use gel coat over the bare fiberglass and repaired areas to lock it all down. For those that have not used gel coat it sands just like like you are working with dry wall fillers. It fills, sands easily, and makes a lot of dust. I think it sands easier than automotive primer surfacers.
For those that say do not gel coat because it is not a boat. Think of the abuse a boat takes bouncing over the waves!
This is what has worked for me I am not forcing my way on to you. I only chimed in because some have made up their minds without ever using gelcoat.

DUB

THANK YOU, '67vetteal', 'TCracingCA' and last but not least '64Corvette'

When I write the 'stuff' I write I am NOT trying to 'force feed' people into doing it MY WAY. AND BY NO MEANS am I EVER NOT wanting ANYONE to express their views or experiences.

I also have been doing these Corvette before this new way of grouping them into 'C' categories. How ridiculous...because there is a mile of difference between a 1968 and a 1982. I just do not get it. I think that this world is getting LAZY and or someone with NOTHING better to do came up with it and is seemed 'CUTE' to use it so a person can sound like they know something....BUT...actually do not know jack squat about Corvettes. WHY do I write this??? Because I get people who call me and say: "I have a C3 and..." And that is when I have to stop them and ask them:"WHAT YEAR do you have?"

TCracingCA, I agree. WAY back when the PPG epoxy primer just came out...and I was still shooting lacquer...and red hardener was still a common place when using fillers. I found that applying the green epoxy over the body work made it so the pigments in the fillers would not bleed into paint jobs. It saved my backside MAY TIMES.

When I do steel body car...for what it is worth and I know it is not available in some areas. I use a primer from NEXA that I can apply onto the bare steel that will allow me to apply a body filler and protect the bare steel from possible rust building up from the filler curing and producing imposture...or moisture getting trapped between the filler and the bare steel when applied. I stopped using the PPG epoxy primer because it has bit be before and I just can not get past eh fact that the PPG epoxy primer is somewhat soft and if I apply a layer of hard body filler on it and then re-apply the PPG epoxy primer to exposed bare steel that showed up due to sanding...AND this layer is also soft...and I cover it with a hard filler...it is like...in an extreme way of thinking...like slapping peanut butter between sheets of thin wood. It will be able to 'move' around when curing.

YES...I KNOW...for years and years bodymen have applied filler on sanded bare steel and it lasted. I am not disputing that...BUT...I have also ground down body filler applied on BARE STEEL and have seen RUST that was developing...and YES....I can tell the difference in rust that was not ground out due to heavy pitting and rust beginning to gain strength.

64Corvette,
I am GLAD you commented and give a personal experience to it so people can see that it can be done and you do not have to go into a spa to heal when done due to ALL of the hard work.

Especially when you mention boats in your comment. And THAT is what many people do not seem to consider or understand. A boat can be in water for a very long time and depending on hull design NO WATER will get past the gelcoat. AND it is IN WATER all the time. SO if water can not go through it...then NO major containment will pass through it from the UNDERSIDE of a panel and cause bubbles...ESPECIALLY if the gelcoat was APPLIED correctly and enough mil's of gelcoat were applied. NOW..if a Corvette is covered in a small steel garage that has very poor air circulation and has water on the floor all the time or gets water in it from time to time and the garage gets HOT like a sweat box....I can pretty much write with confidence that a gelcoated Corvette would hold up longer before moisture contamination would begin to cause the gelcoat to begin to fail. And it really would not matter if the car was covered.

In my opinion...in regards to protection, gelcoat is like a turtle shell.

DUB

DansYellow66

If I ever paint another Corvette I want to use the gel coat you found. That Ecklers Gel Coat is tough sanding - especially until you get through the waxy surface. Good post.

MrPbody

What is it about painters who "do this for a living" that makes them so uptight and hostile about anyone who does things differently than they do? Oh, they're all very careful to (yell) their short little disclaimers. for example: ["When I write the 'stuff' I write I am NOT trying to 'force feed' people into doing it MY WAY. AND BY NO MEANS am I EVER NOT wanting ANYONE to express their views or experiences."] like that really makes the long drawn out string of mis-quotes and false accusations that always follow all ok. well it doesn't. I'm always happy to hear how other people do things. we should all be able to learn from each others successes and failures. I have, in fact, used gel coat in the past, and stated that in a previous post. I was shown a way that works better for me, and that way is by using SPI, or other high quality epoxy primer. If you prefer gel coat that's fine by me, and I've NEVER said it was "a product that always fails". in fact I know it works just fine. I just don't care to hassle with it when there is a vastly easier product to use that provides a 100% equal end result.
To everyone else reading this I apologize for feeding the trolls. I'm just really sick of being mis-quoted and otherwise mis-represented by these goofs.

Russ

ohiovet

Last year I had a 57 Corvette painted which sat for 40 years after being body worked and sprayed with red oxide primer.
The primer sanded off easily, then the car was sprayed with a high build primer and block sanded. This was repeated 3 times until the desired straightness was accomplished. The car was then sealed with a diluted primer and painted.
The paint and body look great after 1 year.
My other 57 was stripped to the glass with 80 grit paper then primed and blocked a few times then painted with a BC-CC . After 4 years and 5000 miles it has no flaws due to the painting process.
So do what you feel is best for your situation.

Dave Tracy

I can't resist stirring things up a bit. PPG's DPLF is a thin epoxy primer. Due to living in California, DPLF is no longer available so PPG has DPLV(low VOC) This material is much like the high build primer, K36, and can be sanded.

TCracingCA

Dawn? Putting a soap down under finishes! A big no no! If someone has the proper budget, then they should use the same thinning products that will be mixed with the sprayed materials to wipe or even alcohol would be a better choice! You especially don't want water moisture on your high build primers (such as 2k) or applying those over a water washed surface. Also on metal cars an etching primer is wise, prior to the epoxy, unless your bare metal has perfect prep- free of handling etc. but i would still etch! PS Does it have to be specifically Dawn brand? i hate to hear what would be said if we used another manufacturers dish soap! Would probably solicit a PPG type slam!

"Any other way comment is inferior" quoting you , was the first shot to insulting everyone else! Best way comment???? By you--- Wow!

Gelcoat ignorance, no further comments needed.

Most paint manufacturers/suppliers have painting systems of married materials. If you start with a brand, I would recommend sticking to the same brand for the rest of the project, unless you have done a lot of trial and error testing of compatabilities from differing brands! The thinners and catalysts are more of a compatible concern because of how they might react or flash to differing Companies products, than the materials themself thou! This troll forgot, that you look for products based on your perspective on how they sand!!!!!!!!! Maybe they, the manufacturers should add that to the product spec sheets!!!!!!

TCracingCA

Sanding on epoxy primer, body work must have been poor to do that! Sounds like you use an epoxy coat more as a guide coat. I bet you kept reapplying more and more in your epoxy sanding technique suggested!

Seal coats are probably the most important coat to a high quality job, especially for show cars where you want a consistent base to apply your base coat. Spraying over the sanded surface directly, can leave inconsistency as the layer directly under the paint layer (thin base color) that one applies (especially in more translucent colors), thus the color coat can be compromised, or the fix that the novice will take--- is to apply more paint than wise! Let's see, you damnned a whole brand- ""PPG"" as if PPG was some individual product, because of one bad experience? Sounds pretty suspect! Sanding on epoxy, especially on a metal car, will put scratches in that coat, that will compromise the benefit of an epoxy, under those circumstances, you should just use any other primer! Since the bases are so thin, any sanding particles will readily show, but you have your guaranteed Dawn technique- I forgot! The little grains will show under your clear coating, that you can't sand out!

Trolls!

John McGraw

My $.02


I have been using gelcoat for many years, and I think that it is very valuable, especially on a body that is in bad shape. I used the Eclklers stuff years ago, but now use a PVA cured gelcoat, as it is not as much a pain to sand as the paraffin wax cured gelcoat. The PVA gelcoat is shot, and then a thin layer of PVA is shot on top to cure it. The PVA washes off with some warm water, leaving an easy-to-sand surface that does not clog paper like the wax cured stuff.

For anybody that says the only to treat ANY crack, is to grind it out an glass it up, has never restored a rough body. Aside from the normal cracks, many bodies will have hundreds of small spiderweb cracks. In my opinion, there is no better material than gelcoat to consolidate these cracks and prevent them from telegraphing through in the future.

There are many polyester resin based surfacers out there such as featherfill, that do a very good job as a high build surfacer, but they are not as good for consolidation of small cracks and repairs simply because they have such a high percentage of inert filler material to allow easy sanding and high fill. They are simply not as strong as gelcoat, and in my opinion, nothing else is. Gelcoat is nothing but polyester resin, nothing else. It is the same material that was used to saturate the glass mat on your car when it was made. Thin layers of gelcoat will not cure in the air, so a curing membrane must be used to seal off the freshly sprayed gelcoat from the air.

To those that say gelcoat is not structural. I say BS! They built your body using it.


I will be the first to admit that there are many other ways of restoring a really rough body, but this is what I have done for many years, and it works.

To those complaining about PPG DP-90 not sanding well. you are right. However, DP-90 is not intended as a sanding primer! I only use it on metal components under the finish coat. I have never used it on fiberglass, and can see no value in doing so. I do use it on metal car bodies an top of the freshly prepped bare metal, under the high-build primer/sufracer.

I do not use sealer on most of my paint jobs, but I also seldom shoot BC/CC, so the need for is is not as great. Sealer makes the surface all consistent and absorbs base coat all at the same rate, minimizing material. It is also very valuable in preventing reactions with older finishes that may lie underneath. Most of my paint jobs are single stage urethane, and I usually shoot at least 4 coats to allow for color sanding,and ALL my paint jobs are completely stripped bare fiberglass bodies, so a sealer just is not necessary. I use PPG NCP 271 as my final primer/surfacer, and PPG recommends it for use directly under finish coats. AS a matter of fact, PPG recommends it as a sealer when used reduced!
Before any of you jump out and say that a NCP primer/surfacer is not necessary, I will agree. I like however, keeping minimum material on my shelf, and I do a lot of metal bodies as well, so while NCP 271 is little more expensive than K38, is is a good universal primer/surfacer that can be used on fiberglass or bare metal.


There is more than one method for repairing and painting Corvettes, and this works for me. If you have a different process that is fine, but don't spout off about stuff that you know nothing about, just because you do not like it, or have heard someone else say something about it.
I am by no means an expert, but I have shot a lot of bodies in my 60+ years, and have figured out a few things that work.


Regards, John McGraw

MrPbody

That's good information to know Dave. it's been quite a few years since I've used DPLF , but it left a bad taste for PPG that's hard to get rid of

Russ

MrPbody

WOW. ok, pile on. the more the merrier. the first couple were good painters that just had a differing opinion than me, and I can respect that. a bit harsh in the rebuttal perhaps , but that's ok. TC….. you really should stay out of this as it's very obvious that you can't help anyone. [taking a deep breath]

Perhaps I wasn't clear, or maybe my dry sense of humor got in the way, but for whatever reason I'll try and clear up my position ONCE. but then I'm done. in fact I'm most likely gona be off the forum entirely for a wile, as I'm getting really tired of the intensity lately.

(1) I begin ALL paint projects with an initial scrubbing with Dawn dishwashing detergent (sometimes with a scuff pad). this is not something I invented myself, as many knowledgeable painters also do the exact same thing to rid the body of any heavy layers of wax, oils, and other contaminants that might come back to haunt you later on. most use Dawn simply because it seems to cuts the wax the best.
Automotive wax and grease removers (many of which are also water based these day BTW) are mild by comparison, but I do use them for all subsequent cleaning.

(2) Although I see a lot of painters wash panels that already have sanded body fillers on them, I DO NOT (as I was previously accused of). when I previously said I wash after "heavy body work", what I meant was that I wash after any fiberglass cloth and resin repairs, NOT body fillers.

(3) when the washed body is dry, it gets an overall course sanding and is cleaned off with wax and grease remover, and then sprayed with two coats of epoxy primer.
ALL my body filler work goes on top of the epoxy, which I feel has a much better grip on the glass than any filler would.

(4) As to my opinion that gel coat is too brittle for this use, as well as replying to the comments about boats and replacement parts having gel coat and being very durable:
Boats and replacement parts are made by spraying the gelcoat into a mold just prior to placing the subsequent layers of cloth and resin on top of the uncured gelcoat. the gelcoat essentially becomes one with the rest of the layup. but when gelcoat is sprayed on top of a fully cured glass part, the bond will never be nearly as strong as the part that was layed up together to begin with. it just can't be.
Strength issues aside (hopefully most Corvettes don't get hammered on like a boat anyway) since the advent of quality epoxy primers, I just haven't seen the need for gel coat anymore. but this seems to be the big issue people have with me here. and you are misunderstanding my position. I DO NOT FEEL SPRAYING GELCOAT ON A CORVETTE BODY IS DOOMED TO FAILURE, OR PEOPLE ARE WRONG FOR USING IT. it's just something that I don't feel a need to do anymore myself.

(5) Dub wrote: "The benefit of what the gelcoat is providing can not be EQUALLY compared to any other product. The only one that even comes close to gelcoat is a polyester primer....and that is it."
I understand that when a product has been used successfully for many years, it's hard to even try something new. any maybe there is a very valid point to be made with your successes, but I'd really like for you to at least do a few test panels with the SPI epoxy for yourself,….. or heck, just talk with porchdog a little more about it's use on the glass bodies. I don't know anything about him myself, but you mentioned that you do know him already. Heck I'll buy you a quart myself if you're willing to give it a try. -in the meantime, DUB, do try and calm down a bit. life is short, and these things are just metal and glass not worth getting all riled up over. I'll still try and learn from you, even if you are a grumpy old fart . life goes on.



Russ

TCracingCA

Being counted as one of your trolls (plural)!



You should go see a Doctor about your phobia!

PS been talking base coat jobs, because base was mentioned, but a single stage is more to the tradition of how it used to be done, and the right paint can be color sanded. yes more layers are sprayed down, etc. and I won't put a seal coat down for single stage! Single stage is done just a little bit different than two stage! And I don't like to get water especially in the body fillers! The contaminent should of been wiped down at the very start and not at the point where the heavy repairs were just done! Yes added this to everything else i typed knowing it has zero contribution value!!!!!!!!!! Yes Mr. Pbody, I know you are trying to help me with all of your expertise!!!!

64Corvette

For me it all boils down to you need to be familiar with the substrate that is being painted and what is the best system out there that will adhere to it and make it last the longest. Mid year and older Corvettes were made of fiberglass! The refinisher is going to have to be knowledgeable enough with all the systems out there to make a choice on which system or materials to choose that will give his customer the longest lasting refinish.
When I was learning to paint we had two choices, lacquer or enamel. Today, because of all the technology that has been poured into automotive paint repair the choices are nearly unlimited. We have primers, primer surfacers, sealers, and topcoats that require an activator to be added into the top coat being applied before it will cure. To be a successful painter today you have to be skilled and be a chemist also. You need to keep in mind that all of this technology that has been developed has been developed with the repair and refinishing of metal bodies, not fiberglass bodies. The fiberglass repair and refinish market was too small to put much thought towards it.
As we are seeing in this thread, repairs of Corvette bodies have/are being adapted from the technology that was developed for the repair of metal bodies. Some repairs have been successful and some have not.
With this in mind we need a repair system that is geared towards fiberglass. I would like to insert this taken from another thread.
“Boats and replacement parts are made by spraying the gelcoat into a mold just prior to placing the subsequent layers of cloth and resin on top of the uncured gel coat. The gelcoat essentially becomes one with the rest of the layup. but when gelcoat is sprayed on top of a fully cured glass part, the bond will never be nearly as strong as the part that was layed up together to begin with.”
Older boats were made of the same material as the materials used in Corvettes. I am old, but if my memory is still with me I think boat builders were hired to build the first fiberglass bodies of Corvettes because of their knowledge and skills of fiberglass.
All paint repairs in the body shops whether it is repairs to a metal body or to a fiberglass body is done by a human using a spray gun to apply material to the surface. With this thought in mind, all systems applied by humans are going to be “weak”. But, using the materials most compatible to the substrate that is being repair will make the best and longest repair. Gel coat over repaired fiberglass gives that “shell” that provides a greater compatibility to fiberglass than those developed for the metal bodies.
Once this Gel coat "shell" has cured and sanded it provides a superior base coat to apply the activated primer sufacers, primers and topcoats that are being used in the auto refinishing industry today.
I won't say anymore and by no means am I picking on anyone