Dynel and West system over Fiberglass

[Alerion Sailor]

I'm formerly RTMAN but for some unknown reason I'm unable to log on as RTMAN even asked for a new passwoord 5 time with no reply so I created a new profile and got back on the site.

I have a cedar strip planked Sam Rabel Titmouse finished in Fibreglass in pretty good condition but it has a crack on bottom. I would like to repair the crack with a few strip of Dynel with West System epoxy.

Does anyone know if it will bond well to the fiberglass ?



Rufus

[Todd Bradshaw]

The bond will be OK, but dissimilar fabrics (different amounts of elongation under stress, which these two have rather big-time) tend to be prone to delaminating from each other. If they're adding needed structural rigidity to the hull, rather than just an abrasion barrier, they also have somewhat different flex and rigidity characteristics. So I guess it depends on just how much that area of the boat might be prone to flexing during normal use.

[Salty Sailor]

You should try to match the resin.
is the Fiberglass made with Polyester Resin or Epoxy?

[Todd Bradshaw]

Epoxy will actually stick better to cured polyester than more polyester will.

[wizbang 13]

What about the crack, did it just appear or did the boat meet some violence? Might wanna repair the crack (with some poxy ), then, patch the sheathing.

[Alerion Sailor]

The crack is from drying out due a lack of use it was like that when I got the boat. It is a trailer sailer the fiberglass is for abrasion protection.
My plan is to cover the crack with a few 2 inch strips as a temperary repair to make thing water tight for this season. I think that if the boat was left in the water long enough it take up alot and possibly seal up the crack enough to be fine.

Thanks for your reply.

[Todd Bradshaw]

I think you could patch the crack without a problem, but fiberglass sheathing and taking up water don't generally go together very well. Composite/wood constructions are generally designed to work "dry" - to isolate the wooden parts from absorbing water and to stay that way. The composte components won't tolerate much in the way of water absorption/swelling/shrinking of the wooden parts without cracking or delaminating. If the outside is fiberglass sheathed, I suspect the inside should also be well sealed against water intrusion, as wet wood can only cause problems and eventual rot.

[Alerion Sailor]

Todd, I believe your right, the crack may have also been caused by water (snow melt) freezing in the bilge and crack the the bottom. Everythin seem structurally strong so I'm going to do the repair and see, I think I'll do the inside as well because it is also FG.