Matching gelcoat with a colorimeter ?

[Leeward Rail]

Matching gelcoat with colorimeter...

Has anyone done this?

Do gelcoat companies has a way to match their colour to Lab, RGB, Hex etc. like you can with paint ?

Did a quick Google search and can't seem to find any info, and figured I would ask the group before I spent half a day making phone calls.

 

[PaulK]

Haven't heard of anything like that. Seems like someone with that ability would be advertising heavily to let people know. AFAIK you have to tint the gelcoat with colorants until you get the right mix for the color you need. Then it invariably shifts colors when it is finally cured. Paint pigments might work with gelcoat, so then you'd have an answer. Might be worth a try to find out, unless someone's already tried and can tell us.

 

[sail sfbay]

To match gelcoat colour recently on a 38 and 18 year-old boats, I went to Spectrum (see catalogue) and was able to match the colour perfectly on both. You can also take a chip to your local automotive body shop who can also match the colour.

 

[jnorten]

Use the advice shared in the previous posts. I will add in to trust your eyes. Electronics are a great tool, but don't overcomplicate this one.

 

[Leeward Rail]

You can also take a chip to your local automotive body shop who can also match the colour.

Electronics are a great tool, but don't overcomplicate this one

Modern autobody shops and autobody paint suppliers use colorimeters ,aka electronics, to more accurately match colors because it can easily compensate for faded paint vs simply mixing to the original non-faded color and adjusting tint as needed and feathering the paint when spraying.

I restore vehicles for fun and they always use a colorimeter now to get the color mix, if you have a sample they can scan.

 

[Leeward Rail]

To match gelcoat colour recently on a 38 and18 year-old boats, I went to Spectrum (see catalogue) and was able to match the colour perfectly on both.

Spectrum will be my first phone call since I have had success with them before. They had the OEM color listed for the other boats I did touchups on.

Unfortunately they don't list the yellow used by C&C but they may know what the formula is. We shall see.

I have tinted gelcoat before, but it is a bit of a PITA to start from scratch.
A closely matching OEM mix would be a good starting point for DIY, on site, tinting.

Unfortunately no pros do on site tinting here.

 

[sail sfbay]

My 1984 boat was an off-white, close to a light and purchased a Spectrum Grady White 1995-2004, off white gelcoat patch kit from the Spectrum catalogue and guess what..........first kit matched perfectly. So you might find the color off their catalogue that match your boat without time-consuming trial and error mixing colors like my gelcoat contractor did.

 

[Justin_NSA]

Isn't a colorimeter a proctologist's instrument?

 

[sail sfbay]

Colorimeter...........any of various instruments designed to determine the color of something, by comparison with standard colors or by spectroscopy What does colorimeter mean - Definition of colorimeter - Word finder (findwords.info).......just saying.

 

[rgranger]

Isn't a colorimeter a proctologist's instrument?

That would be a colonimeter

 

[Leeward Rail]

any of various instruments designed to determine the color of something, by comparison with standard colors or by spectroscopy

Traditionally the devices for paint matching are large and expensive, but like many electronic devices that include optical sensors, there are now, handheld units at very reasonable prices.

https://www.amazon.com/dp/B084Z62KX3/

 

[Justin_NSA]

Traditionally the devices for paint matching are large and expensive, but like many electronic devices that include optical sensors, there are now, handheld units at very reasonable prices.

I agree. I bought a Refractometer for peanuts on Amazon . I use it to test my Antifreeze

https://www.amazon.com/Antifreeze-Coolant-Refractometer-Automobile-Windshield/dp/B07DLDZFJX/ref=mp_s_a_1_4?crid=2TQOEH7OBE0X0&keywords=refractometer&qid=1645323141&sprefix=refract%2Caps%2C174&sr=8-4#

 

[jnorten]

I've used Spectrum to match my early 80's Catalina white. It's pretty good (nearly perfect, but not p-e-r-f-e-c-t) without modification. I also found white MarineTex epoxy putty (more specifically WM's version) is pretty darn close too and cheaper. I'm fussy, but only 6 feet fussy. If it's good from 6 feet, then it's good for me. The electronics are fantastic, but will still require some delicate mixing of drops of tint. . . .Oops overdid it by one drop of tint. . . .Now gotta' try again. . . .

 

[Leeward Rail]

The electronics are fantastic, but will still require some delicate mixing of drops of tint. . . .Oops overdid it by one drop of tint. . . .Now gotta' try again. . . .

100%.
Matching old colours sucks. At least the gelcoat isn't a metallic where the particle size and how they settle when applied, affects the colour perception. I have played enough with automotive paint that I wish the best to anyone who tries to patch an old 70's speedboat.

At some point I plan on repainting the hull. The OEM Banana Yellow is IMO ugly.. horrible... Should be banned..
In the meantime even a 6 or 10 ft match will work.

I haven't done larger areas of gelcoat before so this will likely be an adventure.
Stay tuned.