Make your moulds interlocking in 2 halves. Then when you trim the finished part to the edge, you can place everything back in the mould to bond the two halves together and it should align perfectly.  

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Yeah, I thought it would be Prepeg, my application will be Infusion, it is best to make the mold with flanges in another more discrete area.

Dead easy with pre-preg. But harder with infusion, but still doable. Either way, just need to take your time and be meticulous about it.

How can I get perfect alignment in two-part joining?

Follow image:



The green line is the joining area of the two parts and the yellow lines is identifying the perfect alignment.