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Re: Epoxy: Epoxy Brittleness question
By:Sam McFadden
Date: 9/29/2009, 11:12 am
In Response To: Epoxy: Epoxy Brittleness question (Mac McCaskie)

Mac,

The white appearance you describe is overwhelmingly caused by de-bonding between the glass and the epoxy, not fractures in the glass. Technically speaking, this is not brittle behavior. Rather it is an issue of epoxy and fiber/epoxy bond strength, so you are on good ground to wonder about the condition of the sizing.

My experience with using Raka, WEST, and MAS suggests that Raka is the softest of the three, and is less likely to be perceived as brittle. My two boats built with Raka have white bruises and scratches. My boat built with WEST and the one built with MAS do not. However, the glass on these two boats was plain weave. The glass on one of the Raka boats was 4-HS satin weave and the other was their 5-oz satin finish plain weave that many builders complained about. Other contributors here have suggested that the tighter woven fabrics tend to show white bruises more than plain weave cloth.

Sam

: All,

: I don't know if I'm obsessing about this quandary or not, so let me know what
: you think.

: I used Raka on my first boat, and dinged it a few times, once on the furnace
: and another time on the deck (let's not talk about what happened on the
: beach LOL).

: Where I dinged it, the epoxy shattered leaving a white scar or bruise and
: leaving the fabric visible. Is that normal with Raka or all clear coating
: epoxies?

: Now I'm about to start no's 2 and 3 kayak (modified, dome top, Great Auks). I
: wonder if a less brittle epoxy is available and suitable for our little
: boats.

: Your comments please! Thanks

Messages In This Thread

Epoxy: Epoxy Brittleness question
Mac McCaskie -- 9/28/2009, 11:06 pm
Re: Epoxy: Epoxy Brittleness question
Robert N Pruden -- 9/29/2009, 11:11 pm
Re: Epoxy: Epoxy Brittleness question
Malcolm Schweizer -- 9/30/2009, 8:23 am
Re: Epoxy: Epoxy Brittleness question
Robert N Pruden -- 9/30/2009, 11:44 am
Re: Epoxy: Epoxy Brittleness question
Sam McFadden -- 9/29/2009, 11:12 am
Re: Epoxy: Epoxy Brittleness question
Mac McCaskie -- 9/29/2009, 11:00 pm
Re: Epoxy: Epoxy Brittleness question
Sam McFadden -- 9/29/2009, 11:56 pm
Epoxy Brittleness question
Jay Babina -- 9/29/2009, 8:56 am
Re: Epoxy: Epoxy Brittleness question
John Van Buren -- 9/29/2009, 7:35 am
Re: Epoxy: Epoxy Brittleness question
Mac McCaskie -- 9/29/2009, 9:19 am
Re: Epoxy: Epoxy Brittleness question
Bill Hamm -- 9/29/2009, 12:48 am
Re: Epoxy: Epoxy Brittleness question
Brian Nystrom -- 9/29/2009, 7:21 am