Several builders use hybrid fabrics, one material in the woof, another in the warp.
Combining carbon and Kevlar/Twaron looks great but does not work well, as the fabric is prone to zipper tears. The aramide stretches, the carbon cuts, we have a long tear across the carbon/glass strands.
Combining two colors of Kevlar and in Bell, both variations, is fine, but. The colored Kevlar is Kev 29, used in fire clothing, bullet proof vests, etc. It's coating is not resin friendly and weavers suggest no more that 25% Kev 29 in a fabric used in lamination. [Hence Bell's tweed, 25% black in a former life, now red.]
I do not know if Blue Steel is 50% or 100% Kev 29, but either number is more than 25. We made some all red, 100% K29 hulls at Bell, but , in the words of Archie Bunker, "Stop that there, right now!" when we got the news. But faith springs eternal in humans.
Modern armour theory suggests compression layers, glass or carbon on the outside; high tensile layers, Aramid, Spectra, M-5, Vecrtan, Innegra, etc on the inside. Those enamored of Spectra are advised to look into it's coating requirements for lamination. The shelf life of the coating is absurdly short, leading to wild sheet delamination when over-age material is utilized, but again, faith often trumps fact.
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