Sorry but I am perplexed about the concern about maintaining zero epoxy in the bond area between the edge and the base, or perhaps I am completely missing what is being discussed.
I am an expert in adhesion science. CA's are worthless in my opinion and are simply not structural for a wide range or technical issues that are not of interest to anyone.
So why not use the epoxy to adhere the edge to the rest of the ski?
Help me understand this issue before I make my first pair.
Cheers,
Bloefeld
Rubber toughened CA's
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skidesmond
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No, you want epoxy over the edges and the base and the epoxy to fill in the tines. The CA is to only tack on the edges until you layup the ski. If you had a bottom mold/cassette that could hold the base and edge in place (like RichUK does I think, and some others) you could get away with using epoxy, but the tolerance and fit of the mold has to be very precise.
The traditional approach - CA's are applied to the face of the base material. This tacks the edge set in place until it can be placed in the cassette. If you are aiming for a full wrap or you have not found the right trim cutter to provide a clean edge to the base material while cutting, then a gap may form between the edge of the base material and the edge set. This interface is the cause of concern, water ingress causing delamination - the epoxy that floods this gap during lay-up may crack over time and or fall out.
Using a 3D cassette may well solve this problem, if the base material expands before the epoxy get a chance to seep into any nominal gap. Certainly this would be the case, if pre-preg is being used. In the absence of a cassette, CA's don't solve this problem - although there is some suggestion they are being used for this purpose. They are too brittle and the edge of the base material has not been treated for bonding. The main option being explore is neo-prene adhesives. I've discounted the epoxies used by ski-techs for repairs (when building in the winter).
I don't always use 3D cassettes and I'm currently getting away with not using CA's. What I'm using appears to create the seal between the two parts and still allows the epoxy I use to do it's job.
Using a 3D cassette may well solve this problem, if the base material expands before the epoxy get a chance to seep into any nominal gap. Certainly this would be the case, if pre-preg is being used. In the absence of a cassette, CA's don't solve this problem - although there is some suggestion they are being used for this purpose. They are too brittle and the edge of the base material has not been treated for bonding. The main option being explore is neo-prene adhesives. I've discounted the epoxies used by ski-techs for repairs (when building in the winter).
I don't always use 3D cassettes and I'm currently getting away with not using CA's. What I'm using appears to create the seal between the two parts and still allows the epoxy I use to do it's job.