laminating on to cured epoxy

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laminating on to cured epoxy

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chriscnf	c chriscnf posted 5 Years Ago HOT Topic Details
c Group: Forum Members Posts: 34, Visits: 2.7K	Hi guys...I'm messing around with hand layup of twill carbon in a complex three part mould. The three parts are laid up seperately and then joined with an inflation bladder. There is an advantage for me in letting the parts cure to B stage (not sure wha range of cure that covers) and then joining with fresh uncured epoxy. The question is what state can you let epoxy cure to before it needs sanding for good adhesion and what is the chemical process that stops expoxing adhereing well once cured? Cheers...Chris
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Matt.F	M Matt.F posted 5 Years Ago HOT Post Details
M Group: Forum Members Posts: 4, Visits: 13	+x Warren (Staff) - 5/5/2020 11:59:16 AM Although the bond strength wont be quite as high, in that kind of design, it won't be an issue as you are wrapping around the tube so anything below is mechanically locked into place and there is no real mechanism to shear off the layers. A lot of UD fibre in the lay up will certainly help with the hoop strength on those brackets with a bit of plain for all round strength. Weather you stop and let it cure after step 2 is probably more an issue of practicality, Hi Warren, please could I send another question your way? I'm pretty happy with the foundation band (step 1 from my previous post) I've now cured on my pole bracket project. Step 2 I think I've massively underestimated building the material required to bed in the two steel inserts. Bedding the inserts with hand lay up would take masses of cured sheets so I'm wondering is there a fairing compound / filler I could use in this instance? I'm hoping to do a test project with a quick fix style epoxy putty (Quicksteel or similar) over the weekend to see if it bonds well and won't crush, that would be very easy to work with? Then I can move to step 3 banding the entire project with unidirectional & plain to give the required strength. Thanks in advance for any wisdom! Matt
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