Strength: Folded-Up Cloth vs Loose Fibers?
Surf ski (long, skinny sit-on-top kayak).
The deck is bonded to the hull by what looks like fiberglass mixed with polyester resin. The bonding stuff is about 1/8" thick. Can't tell if there's a flange yet. Around the seat well, there is about 18" where the deck/hull connection is cracked. I figure I'll chisel out the existing mix - and try to feel out the flange, hoping that if it's there it is flat and not s-shaped. Then I'll trowel in a mixture of epoxy and either loose fibers or just wadded-up cloth. Does this sound right? Will there be a strength diff between the two fillers? -- PeteCresswell |
Strength: Folded-Up Cloth vs Loose Fibers?
"(PeteCresswell)" wrote: Surf ski (long, skinny sit-on-top kayak). The deck is bonded to the hull by what looks like fiberglass mixed with polyester resin. The bonding stuff is about 1/8" thick. Can't tell if there's a flange yet. Around the seat well, there is about 18" where the deck/hull connection is cracked. I figure I'll chisel out the existing mix - and try to feel out the flange, hoping that if it's there it is flat and not s-shaped. Then I'll trowel in a mixture of epoxy and either loose fibers or just wadded-up cloth. Does this sound right? Will there be a strength diff between the two fillers? -- PeteCresswell Well, I'd take a different tack... Trying to lay glass over an open hole is a bitch, buddy. First, is there another area like the area that is cracked where a "splash" could be taken? If not, since it's a crack and not a crater... Lay some plastic sheet over the area - painter's drop or the like, but not too thin. Lay out fiberglass cloth ON the plastic sheet - in situ - and wet out with EPOXY resin. Then cover the mess with another piece of plastic sheet and you have a wet lay up - that you can handle - a wad! Three or four layers of fabric will do. Lay the wad in place on the dammaged area and work it into shape. And let it cure. That makes a "splash". It is a very thin fiberglass molding of the problem area. The splash is the same basic shape as the place where the repair is needed. On fairly flat areas it doesn't sound like much, but get into the corners and compound areas, and a splash is a handy thing to have. Yes. it may be a little off size, if it's laid on an outside surface, but it's flexible stuff.... NOW carve out the dammaged area as required. (1) with the idea of making the hole and the splash fit each other (feathered edges, etc) or (2) with the idea of using the splash as a backing plate - behind the dammaged area. (look Ma, no hole!) The backing plate approach is the easiest - if you can get behind the dammaged part - or sized so that the backing plate can be passed through to the back side. Scuff the back side of the dammaged area and the front side of the splash (for some "tooth") and glue in place with T-88 and aluminum pop rivets around the perimeter. Once the T-88 cures, drill out pop rivets, and clean up around the patch with a die grinder, and prep for new glass to be laid on. (feather the edges of the old glass, knock off glubs, etc). Then lay in glass (cloth over matt) patches to fill the surface level again. (will usually take care of the rivet holes too)) Knock the rough glass smooth (I heart my die grinder!) and slick the surface up with a little bondo or micro. Gell coat - or paint? I personally never use matt without a fabric "close out" over it. Too hard to get a decent glass/resin ratio otherwise. And itabsolutely refuses to float in mid-air... Richard Lamb the CaveLamb |
Strength: Folded-Up Cloth vs Loose Fibers?
Per Steve Baker:
Izzat you? Seen any whipsnakes lately? ;-) Steve (aka "Boat-Boy") Baker Yes. Trying to get my Findeisen spec ski back on the water so I can sell it. .... and dreaming of Bernicia.... that is a *really* nice area. Even Rio Vista - which somebody said was "a little town out in the middle of nowhere" - was beautiful to my East Coast eyes. -- PeteCresswell |
Strength: Folded-Up Cloth vs Loose Fibers?
(PeteCresswell) wrote:
Yes. Trying to get my Findeisen spec ski back on the water so I can sell it. Pete, For that kind of repair, if it's just cracked, grind or sand back a little, then lay on a wetted-out piece of cloth or mat (woven rovings or Chopped Strand Mat) that is about 2" bigger than the crack. Sand everywhere your patch will touch. If using cloth, aim for a total of 18 oz, and you should be fine for a surfski. Steve "catch you at AM-B" |
Strength: Folded-Up Cloth vs Loose Fibers?
Per Steve Baker:
Pete, For that kind of repair, if it's just cracked, grind or sand back a little, then lay on a wetted-out piece of cloth or mat (woven rovings or Chopped Strand Mat) that is about 2" bigger than the crack. Sand everywhere your patch will touch. If using cloth, aim for a total of 18 oz, and you should be fine for a surfski. Steve "catch you at AM-B" Two issues: ------------------------------------------------------------------------- 1) The 1" fiberglass tape that covered the deck/hull seam had started delaminating bigtime. I got it off with a putty knife, a hair dryer, and some gentle persuasion. Plenty dirt/crud under where it had supposedly been bonded. 2) On one side, around the rear of the seat well, the bond between the deck and the hull shows cracks over a distance of about 18". I can move the deck independently of the hull with finger pressure, so I'm guessing the cracks are really a separation of the deck from the hull, but I don't know if there's a flange on the inside and, if there is, if it's flat or curved. Gonna track down the guy who bought out the ski's original maker and see if he can offer any info. ------------------------------------------------------------------------- I think I have the tape replacement process pretty much wired: clean the area obsessively with a sanding block - removing all traces of the prior bonding material and any gel coat and then just 'poxy new tape over top. Not sure whether I need any more resin than is needed to wet out the tape... i.e. would a second coat to fill in the weave add anything besides weight and/or cosmetics? I'm still mulling over the crack repair. On one hand, it seems like I should be able to get some thinned resin to pull itself in there just by surface tension. On the other hand, I have no idea of what the condition of the two surfaces is. My guess would be that they aren't as clean as I'd hope. If I go all the way and carve out the bad stuff, then I have to mix up some resin/fiberglass filaments and stuff it in there. That's where the OP came from: I don't know if I should take the trouble to chop up a bunch of glass or just stuff the folded-over wetted cloth into the gap. The folded-over cloth seems like it would give more control over seepage/weeping on the inside of the hull. OTOH, maybe it's not mechanically strong enough... -- PeteCresswell |
Strength: Folded-Up Cloth vs Loose Fibers?
(PeteCresswell) wrote:
snip I think I have the tape replacement process pretty much wired: clean the area obsessively with a sanding block - removing all traces of the prior bonding material and any gel coat and then just 'poxy new tape over top. Pretty much, Yup! Not sure whether I need any more resin than is needed to wet out the tape... i.e. would a second coat to fill in the weave add anything besides weight and/or cosmetics? Will add just weight, and un-sandability.... I'm still mulling over the crack repair. On one hand, it seems like I should be able to get some thinned resin to pull itself in there just by surface tension. On the other hand, I have no idea of what the condition of the two surfaces is. My guess would be that they aren't as clean as I'd hope. If I go all the way and carve out the bad stuff, then I have to mix up some resin/fiberglass filaments and stuff it in there. That's where the OP came from: I don't know if I should take the trouble to chop up a bunch of glass or just stuff the folded-over wetted cloth into the gap. The folded-over cloth seems like it would give more control over seepage/weeping on the inside of the hull. OTOH, maybe it's not mechanically strong enough... Can you send photos of the area? Addie as ever, saildesign @ aohell.com (you know what it's really called, right?) Steve |
All times are GMT +1. The time now is 11:32 AM. |
Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 BoatBanter.com