Gel Coat Spider.

Feb 2, 2018
11
Grampian 26' Grampian fixed keel model Gulf Breeze
Is there a relatively easy way to fill in gel coat spider cracks that still makes deck look OK?
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
No easy way. It is time consuming and expensive. Need to grind them out with a dremel tool, fill with epoxy (maybe) then color-matched gelcoat (from Spectrum), sand, wax and polish. Do an internet search on "repairing gelcoat spider cracks" to find detailed repair strategy videos and articles. If they are in pattern gelcoat you will need a matching pattern mold, which you can purchase from Gibco. If they are at stanchions you will need to remove them.
 
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Feb 2, 2018
11
Grampian 26' Grampian fixed keel model Gulf Breeze
No easy way. It is time consuming and expensive. Need to grind them out with a dremel tool, fill with epoxy (maybe) then color-matched gelcoat (from Spectrum), sand, wax and polish. Do an internet search on "repairing gelcoat spider cracks" to find detailed repair strategy videos and articles. If they are in pattern gelcoat you will need a matching pattern mold, which you can purchase from Gibco. If they are at stanchions you will need to remove them.
Thanks for the insight.
 
Jan 4, 2006
6,491
Hunter 310 West Vancouver, B.C.
If you can walk and chew gum at the same time, you can repair spider cracks.

All except for the for the colour matching in your case, which may be a bit of a bugger. Lots of trials I'm afraid. I'm lucky, my colour is an exact match for white get coat. Contact a supplier of FG products in you area for ideas on how to colour match to your requirements. Once you have a can matched to the colour you require, you're set for life. The last 1/2 pint can I just finished off was 8 years old and kept in the refrigerator. The actual repair work requires a grade four reform school education.


See #3 and #6.


See #7.
 
Jan 4, 2006
6,491
Hunter 310 West Vancouver, B.C.
Andy is the most knowledgeable guy I've seen on the web when it comes to repairs.

In this set of vids. I have to disagree, these are not spider cracks but rather structural cracks. IMHO, spider cracks are tiny cracks that appear with no apparent stress source. Seems to be one of these things that just happen. I have had to repair spider cracks on my toe rail which is a solid massive slab of FG running the length of the boat :

1665863210122.png


No way that thing is subject to undo stress.

I have not seen any indication of failure in any of the spider cracks I have repaired using the simple, painless, reasonably clean method shown in post #6. For the heavier repairs which Andy is demonstrating yes, go deep and add additional layers of cloth for extra strength.
 
Oct 22, 2014
21,107
CAL 35 Cruiser #21 moored EVERETT WA
Ralph.
We are not in disagreement. What I shared was a series of approaches to address the differing cracks that I have seen occur on boats built in the 70's. Certainly some of the cracks are of less severity than others. Each type needs to be explored and a resolution decided. Cracks in gelcoat can have several cause. Our boats generally flex as they move through the water, some more than others. Gelcoat does not flex like layered fiberglass. Thus the cracking we see in areas of stress. As Andy indicated in the first post, he was planning on painting the boat. In order not to have the crack imprint through the paint his method of "go Deep" was about stabilizing the area to prevent imprinting.

You have sure kept your rails in top shape. Your skill are to be admired.
 
Jan 4, 2006
6,491
Hunter 310 West Vancouver, B.C.
I guess I got a little derailed when the original post was about spider cracks and we were now drifting into structural cracks. I'm back on the rails again :doh:.

You have sure kept your rails in top shape. Your skill are to be admired.

Thanks for the compliment. Don't even want to think of the hours and back pain that has gone into oxidation removal and waxing every year. And all for what .................. so every bird in the marina can drop by to crap on the nice shiny target. WHY I ask you:facepalm: ?