>... Talc - cheap-ass filler used in bondo and 'cow flap' polyester used in our >c&cs.
Is "cow flap" polyester the same orange, hard filler used by Bruckmann's in the early 70's? I have heard it called "bog". Many of the failed balsa areas in Calypso's deck were bordered by the orange "bog" filler. Water intrusion from one place would migrate through cracks in the bog to many other places. Back in 1998 we repaired hull fractures (actually leaking sea water into the bilge) caused by the forward keel stub's bog failing to prevent flexing. My best guess is 28 years of hard sailing made harder by the use of hydraulic back stay tensioners stressed the solid glass layup to fracture. Sea water found the path into the bilge through the cracked bog filler. The 1998/99 repair was to grind out all the bog, re-laminate inside and out, and finish up with much less epoxy filler. After looking at the C&C build drawings for the early 43's I noticed C&C/Bruckmann's added extra structure forward from the mast step to stiffen this area. We will be adding something similar during the current deck restoration project. Martin DeYoung Calypso 1971 C&C 43 Seattle -----Original Message----- From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Dave via CnC-List Sent: Tuesday, November 24, 2015 5:11 PM To: cnc-list@cnc-list.com Cc: Dave Subject: Stus-List Epoxy fillers and other stuff... Glass strands (various lengths from milled fibres to chopped strands)- hard to fair but strong - structural. Fumed silica - cab-o-sil - this is a colloidal filler, it keeps the epoxy from flowing. This is not the same thing as making it 'thicker' - glass will do that, but without silica, the reain can still run, fillers can still sag. You need silica to make putty. The stiffness of the mix will vary - is this for coating, laminating, adhesion with gap filling, fairing, structural filling? Micro balloons - fillers with various degrees of fair-ability. Different materials. Talc - cheap-ass filler used in bondo and 'cow flap' polyester used in our c&cs. Peel ply - a nylon material that is porous to epoxy that can be lifted off after cure. Leaves a finished surface. (More significant in vaccum bagging). Nylon taffeta from the fabric store works. Acetone can be used on a cloth to help shape 'b stage' epoxy. Isopropyl alcohol for clean up (a challenge) Waxed paper or 'tack tape' works as a release. I welcome critiques or additions.... Lots of good info on the gougeon site and many others . Great stuff to experiment with. Dave Sent from my iPhone _______________________________________________ Email address: CnC-List@cnc-list.com To change your list preferences, including unsubscribing -- go to the bottom of page at: http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com _______________________________________________ Email address: CnC-List@cnc-list.com To change your list preferences, including unsubscribing -- go to the bottom of page at: http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com
