Delamination of Carbon Foam Sandwich on boat floor

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Delamination of Carbon Foam Sandwich on boat floor

Delamination of Carbon Foam Sandwich on boat floor

Author	Message
Henry	Henry posted 7 Years Ago HOT Topic Details
Group: Forum Members Posts: 3, Visits: 21	Hi guys, just wondering if i could get some advice on how to repair the deck on my sailing dinghy! The picture shows the area of de-lamination (the green rectangle) , the only stress that this section goes through is when I stand on it whilst sailing, however the top skin has come away from the foam core, and I have a feeling the bottom skin has split along the underside of the 'v', so as you can imagine, as you put weight on the section, it deflects around 1-2cm, and makes crunching noises as the foam deforms. I have had a quick attempt at repairing this by drilling a series of holes, and injecting resin so that it saturates the foam, however this still hasnt worked, and the section still deflects when pressure is applied! My current plans are: wet lay-up a ~20 x 120cm piece of heavy biax weave along the centerline and hope for the best, but i am now doubting myself as the top skin of the sandwich is not fully attached to the foam, sadly i do not have access to the underside so cant strengthen there! The direction of fibres is shown by the red lines (45-deg from top to bottom in picture) I want to spend the least amount of work time (curing time is irrelevant) because i want to get sailing! so chopping out the section and replacing is a route i dont really want to take! any help would be muchly appriciated! - Henry
	Reply Like 5
Fasta	Fasta posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	If the bottom skin of your deck is broken then you need to repair that, adding more stuff to the top of the deck wont help much. Best fix would be to cut a clean rectangular patch out, then bond in some flat fibre glass/carbon strips about 30mm wide onto the underside edges of the open hole creating a 15mm wide flange and hold them in place with pegs while the glue dries. Prepare and new piece of PVC foam to fit but only fibre glass/carbon the one side (underside), once cured you can then bend and bond that panel into the hole and onto the flanges you have, weight it in place until cured. Then clean up any daggy bits and fibreglass/carbon the top skin overlapping back onto the remaining deck. Paint, non skid. Happy mothing. Fastacraft Facebook page
	Reply Like 3
Hanaldo	Hanaldo posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	You could attempt to infuse the repair so that the resin gets drawn into the voids, but you might struggle to get a seal on it. Realistically I think chopping it out and replacing it is the only way to fix it properly, so I would be putting that on my to do list. I'm sure you can do a quick fix in the meantime yo get you through the season though, hopefully one of the more experienced boat guys will be along shortly... waits for Fasta
	Reply Like 5
Hanaldo	Hanaldo posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Ha, look at that! Didn't even have to wait long
	Reply Like 3
Henry	Henry posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 3, Visits: 21	so, if i was to do that at the end of the season when mothing is too cold for me! what would you suggest doing as a tempoary fix, dont mind how heavy or ugly it is, i just dont want to fall through my deck floor! and then when winter comes around, i will chop the panel out, as i already have another panel to chop out and replace anyway! there is a small void between the epoxy saturated foam, and the top skin, so i could try and pack some more resin into this area? and possibly some extra carbon weave to beef up the top skin a little, just to take some of the weight away from the unsupported middle and more towards the supported sides? I have some weaved uni, lots of heavy biax, and a small amount of plain weave to play with! - Henry
	Reply Like 5
Henry	Henry posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 3, Visits: 21	I can see why adding strength to the top layer wont help much, and it makes complete sense! but i want to try an avoid cutting and sticking until the end of the season, and just want to not fall through the floor unexpectedly!
	Reply Like 4
Fasta	Fasta posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	You could cut a hole in the side of the boat hull instead and repair the crack on the underside of deck keyhole style. Then just glue set the repair hole back in place and carry on until you do a better fix later? Fastacraft Facebook page
	Reply Like 4