transom install help and advice

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transom install help and advice

Author	Message
mulltr66	mulltr66 posted 7 Years Ago HOT Topic Details
Group: Forum Members Posts: 1, Visits: 4	Hello, I'm replacing my transom soon and wanted some advice. I need to install 50 oz woven/roven in front of the existing outer fiberglass skin, then 2' inch pvc closed cell foam , then the inner fiberglass skin. Clamping the shape is difficult, so I'm considering vacuum bagging. I'm thinking about applying the vacuum bag around the existing outer transom, over the top, and then down over the new woven/roven and foam. I'm hoping this will pull things together nicely. Then apply the new inner skin with another vacuum bagging the next day. Any advice would be greatly appreciated. Thanks, Tim
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Matt (Staff)	Matt (Staff) posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 680, Visits: 1.9K	Hi Tim, Thanks for the post. What you're suggesting sounds perfectly feasible. I assume you mean 2" (not 2' i.e. foot) foam; if that's the case then although we don't stock a 2" foam (50mm) we do have 25mm foam which you could just layer together. I would suggest our EasyCell 75 Closed Cell PVC Foam (I would imagine its 70kg/m3 density is about right for what you're doing) which you could simply bond two layers together to get the 50mm you need. For the glass, you mention 50oz woven roving; I'm assuming you mean 50oz in total (made up of a number of layers) because 50oz is 1.5kg. In woven roving we have a 300gsm woven glass roving which has a fairly close weave and easy easy to handle and laminate. To make up the total 1.5kg that you're after you'd need about 5 layers which sounds pretty typical. In terms of resin I would suggest our EL2 Epoxy Laminating Resin. If you're vacuum bagging you'll either want the SLOW hardener or a combination of FAST and SLOW (they can be blended) to ensure you have enough time to do the laminating and then get it all vacuum bagged before the resin starts to gel. If you're not in a hurry I think I'd recommend going with all SLOW hardener - this will give you a good hour or more to get the laminating and bagging done before the resin even starts to gel. You can also use some of the same resin to bond your two sheets of EasyCell 75 together. You're probably aware that we have all of the vacuum bagging equipment and consumables that you're likely to need for the vacuum bagging part or you may wish to consider the Vacuum Bagging Starter Kit which includes most of it in a handy starter kit. I hope this helps. If you need to know anything else about the process either myself or someone on the technical will be pleased to help. All the best, Matt Matt Statham Easy Composites / Carbon Mods - Technical Sales Tags boat pvc foam repair vacuum bagging
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Rich (Staff)	Rich (Staff) posted 7 Years Ago HOT Post Details
Group: Administrators Posts: 167, Visits: 4.6K	Hi Tim, One thing to bear in mind is the compressive strength of the foam core. If you have any fixings or fasteners to make through the transom (outboard motor mounts; brackets/cleats/etc.), the common practice for foam cored transoms is to locally (to the thru' fixing) replace the foam with a hard pad of plywood or timber or even a metal pad which have significantly better compressive properties and won't crush when torquing bolts. The alternative being to use a large washer plate to sandwich the area and to prevent the core from crushing. If the transom has no such fixings, you won't need to worry.
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