Gel Coat Repair

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
dleopoldi914
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Gel Coat Repair

Postby dleopoldi914 » Wed Mar 27, 2019 9:59 pm

My 1983 Montauk has some chips in the gel coat above the water line. I want to repair them.

Q1: What color kit from Spectrum do I order?

Q2: Do I mix the Spectrum resin using the mixture?

Q3: Do I apply with a card as if I am [applying spackling plaster to] a wall?

Q4: Do I use 220 grit once it dries to get it flat.

Q5: Do I compound the boat?

Q6: Do I wax the boat?

jimh
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Re: Gel Coat Repair

Postby jimh » Thu Mar 28, 2019 4:54 am


dleopoldi914
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Re: Gel Coat Repair

Postby dleopoldi914 » Thu Mar 28, 2019 7:29 am

I have read this extensively.

Q7: Has anyone used the Spectrum [gel coat]?

jimh
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Re: Gel Coat Repair

Postby jimh » Thu Mar 28, 2019 12:06 pm

dleopoldi914 wrote:Q7: Has anyone used the Spectrum [gel coat]?


The article I suggested be read describes the use of Spectrum gel coat. The people who wrote the article have used Spectrum gel coat. I am sure thousands of others have used it, too. Spectrum has been in business selling these small batches of color-matched gel coat for many years.

I don't understand your question regarding who has used Spectrum gel coat. Are you seeking a list of users?

I pointed to comprehensive and well-illustrated article because it answers many of your questions.

I also have trouble understanding your question:
dleopoldi914 wrote:Q2: Do I mix the Spectrum resin using the mixture?


I don't understand what "the mixture" refers to. Please elaborate on "the mixture."

dleopoldi914 wrote:Q3: Do I apply with a card as if I am [applying spackling plaster to] a wall?

Re-read the article I suggested to be read. The article gives details and advice on application of new materials to the hull surface.

dleopoldi914 wrote:Q4: Do I use 220 grit once it dries to get it flat.

Re-read the article I suggested to be read. The article gives details and advice on the abrasives used for sanding and fairing.

dleopoldi914 wrote:Q5: Do I compound the boat?

I believe you are seeking advice on restoring lustre to the finish of the gel coat. You can use the rubbing compound of your choice to accomplish this. For more advice on restoring lustre to faded or oxidized gel coat finishes, you can read this thread:

http://continuouswave.com/ubb/Forum3/HTML/019754.html

There are many others. Here is a search result.

dleopoldi914 wrote:Q6: Do I wax the boat?

Follow the advice in the owner's manual.

Blackduck
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Re: Gel Coat Repair

Postby Blackduck » Thu Mar 28, 2019 3:09 pm

[Spectrum] will not match your hull color, straight out of the jar. [Spectrum] will have to be adjusted by tinting.

{The original article used the undefined pronoun "it", which I assume referred to "Spectrum." If "it" referred to something else, the author should edit his article to define what "it" meant in a clear manner.--jimh]

jimh
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Re: Gel Coat Repair

Postby jimh » Thu Mar 28, 2019 4:04 pm

A fundamental concept in believing that an off-the-shelf color of tinted gel coat will be an exact match to the present day color of gel coat on a boat made in 1983 involves believing that in 36-years of exposure to sunlight and seawater the original gel coat color will remain unchanged, and that the supplier of the pre-tinted gel coat furnished an exact match to the original color.

If you believe both of those assumptions will be correct, they you can order an off-the-shelf gel coat tinted to the original color of your 36-year-old boat.

For boats that have been maintained in extremely fine condition, stored mostly under cover or indoors, and with little fading or discoloration of their gel coat, buying a small gel coat patch kit in a pre-tinted color is often a very good match.

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Acassidy
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Re: Gel Coat Repair

Postby Acassidy » Thu Mar 28, 2019 4:14 pm

I am sure you know this, but the inside color and the outside colors are different. Desert Tan inside and a sort of off white outside. I do not remember. And don't quote me. I may be totally wrong.

I have used [Spectrum] many, many times, like what you are doing. Usually matched well enough for small repairs.

This is the process which has worked for me.
  1. As long as the repair is not too big you can just use the Spectrum pre-thickened and pre-waxed product
  2. if bigger, then you need to do marine fairing compound first
  3. tape around the repair area
  4. use a Dremel with V grinding bit
  5. fair out the side
  6. widen the repair area
  7. make it as flat and low as possible
  8. have a max of 10% gradient of the damaged area around it (for 1 inch long repair no more that 1/10 " deep.)
  9. sand area with 150 sandpaper up to the tape
  10. don't go past the tape
  11. use the tape to confine the repair area
  12. do not do the repair by sanding more than needed.
  13. remove tape
  14. wipe with acetone
  15. re-tape carefully around the repair in a circle
  16. mix product well
  17. with a two-inch putty knife fill in gel coat level or above the tape
  18. wipe in two different directions
  19. let cure
  20. sand with 150 and 220 down to level with the tape
  21. remove tape
  22. block wet sand stepping up while you remove gelcoat with 320, 600, 800, 1000, 1500
  23. buff
  24. be careful to time your step up sanding to keep from removing too much repair area because you still need to sand and buff out
  25. two or three repairs may be needed if the damage is not filled by the first gel coat repair
  26. gel coat shrinks.

If this does not make [sense] ask.

I can try to explain better.

I have done this like 500 times.

Spectrum is great gelcoat

Is easy to work with and easy to sand.

Archie

dleopoldi914
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Re: Gel Coat Repair

Postby dleopoldi914 » Tue Apr 02, 2019 4:21 pm

Acassidy wrote:This is the process which has worked for me...


Thank you.

Great

This is what I was thinking: tape, grind out, sand, acetone, apply spectrum,do some sanding, it will blend somewhat, color will never be 100%, but better than seeing a small hole.

Which Spectrum kit for a 1893?

To the other: yes. I got it. There are directions. I am looking for an easy repair.

Thank you.

jimh
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Re: Gel Coat Repair

Postby jimh » Tue Apr 02, 2019 7:43 pm

Who is or are “the other”?

The easiest repair is done with your checkbook as the main tool.