Edge Sealing of Sandwich Panels

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Edge Sealing of Sandwich Panels

Author	Message
scottracing	scottracing posted 3 Years Ago HOT Topic Details
Group: Forum Members Posts: 460, Visits: 5.2K	Hi all, Im making some sandwich panels consisting of PET foam core and GRP faces for an interior application. I want the machined edges to be sealed so theres no moisture ingress, I was looking at adding resin or gel coat to the edges, or even a finishing strip. Just wodering if there are any alternatives I should look at? Cheers Gaz
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Hanaldo	Hanaldo posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I like to use tow. Generally I'm doing carbon, but no reason fibreglass rovings wouldn't work the same. Just dip in a pot of resin and squeeze the excess off with (gloved) fingers before running it around the edges. Quite neat and easy, resin and gelcoat can be a bit fiddly to get a consistent coating and then there's no strength to it either. Would recommend masking off the adjacent faces to minimise clean up later, and if your parts are large then this could be a bit of a pain. But works really well for smallish parts, it's what I do on wing end plates etc.
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Warren (Staff)	Warren (Staff) posted 3 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	Our EF1 Black Epoxy Repair Filler can also be used to seal the edges on sandwich core panels (route a few mm of the core material away and then smooth filler into the cavity). Edges filled in this way not only seal the panel from water ingress they also provide an attractive edge which can be polished up to a gloss finish. The quickest option is a rubber edging trim which you can get online or from car building/kit car suppliers. You can just press it onto the edge or glue it on. Some variations even have glue in the u channel. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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scottracing	scottracing posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 460, Visits: 5.2K	+x Hanaldo - 10/25/2021 9:12:51 AM I like to use tow. Generally I'm doing carbon, but no reason fibreglass rovings wouldn't work the same. Just dip in a pot of resin and squeeze the excess off with (gloved) fingers before running it around the edges. Quite neat and easy, resin and gelcoat can be a bit fiddly to get a consistent coating and then there's no strength to it either. Would recommend masking off the adjacent faces to minimise clean up later, and if your parts are large then this could be a bit of a pain. But works really well for smallish parts, it's what I do on wing end plates etc. Yeah that could work, I might use a bit of spread tow/tape instead as the core thickness is 10mm. It's quite a large panel as it's 2.5m x 1.5m so could be a bit of a pain doing it that way but at least it would be structural.
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scottracing	scottracing posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 460, Visits: 5.2K	+x Warren (Staff) - 10/25/2021 4:13:10 PM Our EF1 Black Epoxy Repair Filler can also be used to seal the edges on sandwich core panels (route a few mm of the core material away and then smooth filler into the cavity). Edges filled in this way not only seal the panel from water ingress they also provide an attractive edge which can be polished up to a gloss finish. The quickest option is a rubber edging trim which you can get online or from car building/kit car suppliers. You can just press it onto the edge or glue it on. Some variations even have glue in the u channel. Thanks Warren, I was look at rubber edge strips but ideally I would like a nice clean edge finish. I think the extra work of routing out the edge to fill it could be a pain as the panels are quite large, but I will make some small test panels first and see what works best. Edited 3 Years Ago by scottracing
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Hanaldo	Hanaldo posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	+x scottracing - 10/25/2021 10:41:33 PM +x Hanaldo - 10/25/2021 9:12:51 AM I like to use tow. Generally I'm doing carbon, but no reason fibreglass rovings wouldn't work the same. Just dip in a pot of resin and squeeze the excess off with (gloved) fingers before running it around the edges. Quite neat and easy, resin and gelcoat can be a bit fiddly to get a consistent coating and then there's no strength to it either. Would recommend masking off the adjacent faces to minimise clean up later, and if your parts are large then this could be a bit of a pain. But works really well for smallish parts, it's what I do on wing end plates etc. Yeah that could work, I might use a bit of spread tow/tape instead as the core thickness is 10mm. It's quite a large panel as it's 2.5m x 1.5m so could be a bit of a pain doing it that way but at least it would be structural. The spread tow tape is a little bit trickier, it doesn't work as neatly as the loose tow. Admittedly I haven't tried it on a flat 10mm thick edge, generally only larger radiused edges or smaller flat edges. so it's worth a try. But I suspect you might find it a little messy and tedious.
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