When to Address Spider Cracks

[CTsalt12]

Hi All,

Like all 20+ year old boats (I think), mine has spider cracks.  Some from improper drilling for things like bimini top clasps, and some from stress, like where the transom meets the floor and stern boxes, and from what seems like some impacts on the exterior.

I don't think any of my spider cracks are signs of the structural integrity being compromised.  My transom is solid, as is my hull all around.  I've had it for three years with the same spider cracks and I've been through plenty of rough water.  They are merely on the gelcoat. 

My question is, when does one HAVE to take care of the spider cracks?  My concern is water leaking into the fiberglass, delamination and/or rotting wood in my transom and other areas.  I've heard a rule that if your fingernail doesn't get caught on the cracks you're ok.  Any truth to this?  Obviously they are an eyesore and I'd like to take care of them all, but the truth is that matching the gelcoat will be so hard that it won't be worth it until I paint the whole top cap, that is, unless they could be letting water in.   

[Shine]

cracks can have many origins.  If they are around fasteners then its less worrisome.  If they are on hull or deck, then they are most likely from flexing. Flexing is either not a big deal, or it can be a very big deal - depends where and how bad.  Cant really be of any good help though without pictures 

[fitz73222]

One thing you can do is actually "grade" the spider crack by its location and type. The ones on top of and at the transom connection points that see a lot of stress should be viewed as important if the cracks are trying to lift or flake off and the core could be compromised. They need a grind, fill and re-gel coated to keep nature out of them. If they're not lifting, just rubbing compound and wax will keep it at bay. Non cored surfaces, like around rod holders, gunnel caps, console feet, etc. just need the rub and wax. It's perfectly normal for older boats to start spider webbing because the gelcoat is shrinking with age, they all do it. My 22-2 just hit 42 years old and has lots of spider cracks. I keep the hull clean, waxed and out of the sun as best I can. The sun really plays hell on gelcoat so keeping it covered slows the process down. Keep it clean and reflective with wax seems to really help and somehow moisturizes the gelcoat and water proofs it. So if you haven't compounded and waxed the entire boat, do so. I don't mind a little patina on our old boats. My antique outboards are the same way. I just rubbed out a 57 Johnson I'm restoring and it looks like it was shot with clearcoat, scratches and all! I love leaving them original when I can.

[CTsalt12]

No lifting or flaking on mine. 

Good to know on the compound and wax.  My whole topside gets waxed, but I actually don't usually do the transom.  Now I will.

Fitz,what do you use to clean/wax the outboard cowling?  My Merc is looking faded and dirty.  I think I'll strip the decals down and keep it "murdered out" black and see if I can get some shine back with compound wax treatment. 

[fitz73222]

If you really want it to pop, wash with Dawn dish detergent, clay bar the entire cowling, Meguires 105 ultra cut compound and Meguires yellow paste wax. It will come out very nice!