Swim platform advice needed

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Swim platform advice needed

Author	Message
Massimiliano	M Massimiliano posted 5 Years Ago Topic Details
M Group: Forum Members Posts: 167, Visits: 1.1K	Hi, I am planning to replace the all metal swim platform on my boat with composites ones to save weight. The current solution is as below from a project point of view, I am asking if it does make sense to build the "C" shaped support in fiberglass (as the rest of the swim platform) glued to the plane VS building it in SS and bolting it to the plane. The tube connecting the transom and the swim platform is just for adding strength and load balancing and it is not intended to move or shake (even if some vibration can be forecasted). Thanks
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Make sense from what perspective? Cost? Weight saving? Ease of building? Strength? Could be a yes or a no depending on what your priorities are. Strength wise, mechanically fastening to composites is never ideal, unless you have designed for it. Simply drilling a hole and putting a bolt and nut through a fibreglass laminate will put stress on the laminate and be a weak point over time. So for me, bonding is better - whether that means bonding the U-section or bonding in a fastener to the fibreglass to facilitate bolting. You could simply bond a SS U-section to the fibreglass using an appropriate adhesive, it wouldn't have to be fibreglass.
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Massimiliano	M Massimiliano posted 5 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Hanaldo - 4/6/2020 10:37:45 PM Make sense from what perspective? Cost? Weight saving? Ease of building? Strength? Could be a yes or a no depending on what your priorities are. Strength wise, mechanically fastening to composites is never ideal, unless you have designed for it. Simply drilling a hole and putting a bolt and nut through a fibreglass laminate will put stress on the laminate and be a weak point over time. So for me, bonding is better - whether that means bonding the U-section or bonding in a fastener to the fibreglass to facilitate bolting. You could simply bond a SS U-section to the fibreglass using an appropriate adhesive, it wouldn't have to be fibreglass. Thank you Hanaldo! My goal is to save weight as much as possible but it has to be durable so the SS U-section seems the best compromise. Can you advise the best product to bond SS to fibreglass? And just for the sake of knowledge, how you design composite to mechanically fasten to it?
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Warren (Staff)	Warren (Staff) posted 5 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	Its about spreading the load. So you can use bond on fasteners with large bases, bond on the U shape bracket (as long as it has a reasonable surface area), fit load spreading inserts into the composite, metal plates etc. As long as you avoid the point loading. Even large repair washers are better than a simple nut and bolt. You can have extra reinforcement in that area to make a load spreading pad which the stainless bracket is bonded to. Something like our VM100 Black 10min Methacrylate Adhesive has good bonding properties to composite and stainless. Both surfaces need a rough key, rougher the better, and thorough clean and degrease. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Bang on Warren! I would bond the SS U-section. Faster, easier, stronger, not going to make a significant difference to weight. A methyl methacrylate like the VM100 Warren suggested would be my choice as well, or a toughened epoxy adhesive like Araldite 2015 or Permabond ET538.
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Massimiliano	M Massimiliano posted 5 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Hanaldo - 4/7/2020 11:44:52 AM Bang on Warren! I would bond the SS U-section. Faster, easier, stronger, not going to make a significant difference to weight. A methyl methacrylate like the VM100 Warren suggested would be my choice as well, or a toughened epoxy adhesive like Araldite 2015 or Permabond ET538. Thank you both!!
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