Anyone re-gel coat their car?

[Jeff's First FFR]

Hello all,
I thought, perhaps, I could red gel coat the sanded parting line areas and keep it that way for awhile. I found FFR's source: Merton's.
Just wondering...
Jeff

[ggunter]

You absolutely can regel coat the car. It's no different than a boat. Just be prepared for a lot of sanding and buffing. You can do it any color you want.

[ggunter]

This boat was yellow and blue when I got it I sanded and made all the repairs and reshot the gelcoat in the colors seen. Sorry about the poor quality pics, they are from a magazine article from the 90's142485142486

[Jeff Kleiner]

I did the body and paint on one 2 or 3 years ago that the owner had knocked down the parting line flash then applied gelcoat to those areas and buffed. He did a good job of it and it looked pretty decent from a few feet away. He drove it like that for a couple of years.

Here's after he did the gelcoat work:

https://thefactoryfiveforum.com/attachment.php?attachmentid=119193&d=1576775068

And the obligatory after paint photo ;) :

https://thefactoryfiveforum.com/attachment.php?attachmentid=117813&d=1574268430

I don't know whether he ever wrote up the process on the forum and I haven't seen him around here for a while but you might turn up a post with info by searching his username "gluisi"

Cheers,
Jeff

[ggunter]

Those are my colors, spectacular Jeff!!!!

[ggunter]

Looks like a piece of jewelry

[Jeff Kleiner]

Those are my colors, spectacular Jeff!!!!

Chrysler code PRV which has been known by a number of different names.

Jeff

[ggunter]

Shooting gelcoat is much like paint. I sanded the entire boat with 320. Wipe everything down with acetone. Tape off your largest color, thin according to the manufacturer add hardner, shoot three coats, flash between each coat, tape your next color, same process. Only about a two hour pot life so make sure you clean your gun. The only thing is sanding your stripes smooth because there is a tape line you have to sand and buff. Of course use fine line tape. And pull your tape before the gel sets or just as its starting to. Wet sand the whole thing and buff that baby shiny. I had that boat 20 years and the gelcoat stayed nice.

[Jeff's First FFR]

I did the body and paint on one 2 or 3 years ago that the owner had knocked down the parting line flash then applied gelcoat to those areas and buffed. He did a good job of it and it looked pretty decent from a few feet away. He drove it like that for a couple of years.

Here's after he did the gelcoat work:

https://thefactoryfiveforum.com/attachment.php?attachmentid=119193&d=1576775068

And the obligatory after paint photo ;) :

https://thefactoryfiveforum.com/attachment.php?attachmentid=117813&d=1574268430

I don't know whether he ever wrote up the process on the forum and I haven't seen him around here for a while but you might turn up a post with info by searching his username "gluisi"

Cheers,
Jeff

I got thie from Merton's:

142510

It is supposed to be the gel coat FFR uses. The can says "Polyester", I hope it is Vinyl Ester. I will confirm with Merton's.
I am planning on spraying the sanded down parting line areas. Wish me luck. It will be a lot of sanding and buffing, I know.
Sometime later I will paint the car the color of my (my wife's) choice.
Thanks for your help.

Jeff

[ggunter]

If it is a factory color that FFR uses I'm sure the manufacturer make it in 500-1000 gallon batches and if you blend it you won't be able to tell the difference as long as the color is exact. If not, like any paint you will see the variation. Here are the differences between the two resins.
The Differences
Polyester resins are formed by the reaction between polyols such as glycol or ethylene glycol with dibasic acids such as phthalic acid or maleic acid. These unsaturated resins are combined with other chemicals sometimes called hardeners or catalysts. This changes the molecular structure and the resulting compound cures, generating heat in the process. Methyl ethyl ketone peroxide ('MEKP') is one such 'hardening' agent.

Vinyl ester resins are produced by the reaction ('esterification') between an epoxy resin and an unsaturated monocarboxylic acid. Essentially they comprise a base of polyester resin strengthened with epoxy molecules in the backbone of the molecular chain. Vinyl esters also use peroxides (e.g. MEKP) for hardening. Both resins can be 'thinned' by reaction with chemicals such as styrene.

Advantages and Disadvantages
On a broad scale of viscosity, vinyl esters are midway between polyesters and epoxy resins, before adding styrene. Thinning effects workability and strength - 'thinning' reduced strength but makes it easier to brush or spray.

Vinyl esters are more tolerant of stretching than polyesters. This makes them more able to absorb impact without damage. They are also less likely to show stress cracking.


Vinyl ester has fewer open sites in its molecular chain. This makes it much more resistant to water penetration ('hydrolysis') which can cause osmotic blistering. Vinyl esters shrink less on curing, which means that 'pre-release' of a laminate from a mold is less significant. Vinyl esters are more tolerant of stretching than polyesters. This makes them more able to absorb impact without damage. They are also less likely to show stress cracking.

The cross bonding of vinyl esters is superior to that of polyesters. This means that vinyl esters bond to core materials much more effectively than polyesters and delamination is less of an issue. Vinyl esters are less sensitive to ambient conditions (temperature and humidity) than are polyesters.

Vinyl esters are more expensive than polyesters through careful calculations are required to assess the cost impact of a significant build project such as a luxury yacht. This is because the relative strengths need to be factored in - you can use less vinyl ester to achieve a given strength.

Both resins are susceptible to 'chalking' - UV breakdown at the surface - unless an additive is incorporated into the mix.

Which to use?

[Jeff Kleiner]

The fiberglass bodies use vinylester resin. I can’t answer for the gelcoat—I generally just turn it into red dust and don’t put it on :p

142511

Jeff

[Jeff's First FFR]

If it is a factory color that FFR uses I'm sure the manufacturer make it in 500-1000 gallon batches and if you blend it you won't be able to tell the difference as long as the color is exact. If not, like any paint you will see the variation. Here are the differences between the two resins.
The Differences
Polyester resins are formed by the reaction between polyols such as glycol or ethylene glycol with dibasic acids such as phthalic acid or maleic acid. These unsaturated resins are combined with other chemicals sometimes called hardeners or catalysts. This changes the molecular structure and the resulting compound cures, generating heat in the process. Methyl ethyl ketone peroxide ('MEKP') is one such 'hardening' agent.

Vinyl ester resins are produced by the reaction ('esterification') between an epoxy resin and an unsaturated monocarboxylic acid. Essentially they comprise a base of polyester resin strengthened with epoxy molecules in the backbone of the molecular chain. Vinyl esters also use peroxides (e.g. MEKP) for hardening. Both resins can be 'thinned' by reaction with chemicals such as styrene.

Advantages and Disadvantages
On a broad scale of viscosity, vinyl esters are midway between polyesters and epoxy resins, before adding styrene. Thinning effects workability and strength - 'thinning' reduced strength but makes it easier to brush or spray.

Vinyl esters are more tolerant of stretching than polyesters. This makes them more able to absorb impact without damage. They are also less likely to show stress cracking.


Vinyl ester has fewer open sites in its molecular chain. This makes it much more resistant to water penetration ('hydrolysis') which can cause osmotic blistering. Vinyl esters shrink less on curing, which means that 'pre-release' of a laminate from a mold is less significant. Vinyl esters are more tolerant of stretching than polyesters. This makes them more able to absorb impact without damage. They are also less likely to show stress cracking.

The cross bonding of vinyl esters is superior to that of polyesters. This means that vinyl esters bond to core materials much more effectively than polyesters and delamination is less of an issue. Vinyl esters are less sensitive to ambient conditions (temperature and humidity) than are polyesters.

Vinyl esters are more expensive than polyesters through careful calculations are required to assess the cost impact of a significant build project such as a luxury yacht. This is because the relative strengths need to be factored in - you can use less vinyl ester to achieve a given strength.

Both resins are susceptible to 'chalking' - UV breakdown at the surface - unless an additive is incorporated into the mix.

Which to use?

Thank you for the very complete analysis.

Jeff

[ggunter]

I forgot to add that you need to add paraffin wax in your spray mix to make the gel coat glossy.

[chmhasy]

142525

I sanded down the seams and applied Merton's red gelcoat, I also followed https://www.youtube.com/user/boatworkstoday gelcoat repair videos for sanding and buffing

[Jeff's First FFR]

I forgot to add that you need to add paraffin wax in your spray mix to make the gel coat glossy.

Thankfully, I read a little before I ordered and got it with wax so it will harden. However, that means I can spray only one coat unless i completely remove the wax before spraying more.
BTW issues with RUNS? How about vertical surfaces or round contours going into vertical?
Proceeding with test sprays.
Thanks again,'
Jeff

[Jeff's First FFR]

142525

I sanded down the seams and applied Merton's red gelcoat, I also followed https://www.youtube.com/user/boatworkstoday gelcoat repair videos for sanding and buffing

Your car is beautiful! That's what I want. Any photos of the process? Any issues with runs?
Appreciate all the help I can get,
Jeff

[chmhasy]

I ground down the seams, brushed on the gel coat just over the seams, applied PVA to let it cure, sanded and repeated, wet sanded with 800, 1000, 1500, buffed with TotalBoat totalbuff rubbing compound

I basically followed https://www.youtube.com/watch?v=v962wu8Euoo his videos for gelcoat repair and buffing

The red from Merton is a shade lighter on my car.

The stuff I got from Merton's is
Red gelcoat no wax
methyl ethyl ketone peroxide hardner to be mixed with the gelcoat
PVA to cover the gelcoat to keep air out after i brushed on the gelcoat

142604142605142603

[chmhasy]

When you get up close you can see imperfections. lots as I am new to gelcoat and fiberglass

[rich grsc]

Like I suggest on the other forum, roll it on