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oekmont - 10/18/2017 9:53:06 AM

The problems with difficult infusions are:

It is much harder to get a frayless  finish in places where you need to cut the cloth. With painting, this isn't a problem for you.

The flow media is much harder to get into complex shapes, than everything used in a prepreg process.

on complex 3d shapes the resin front easily flows around some higher or lower shapes, trapping some voids, resulting in pinholes or (In worst case) unimpregnated areas.

Split mold infusion is a different topic on its own.

If you are careful during the layup, get the bag tight into the corners, and follow the heating instructions, prepreg parts always come out nicely. I never had a failed part.

Infusion is in comparison an art. The process allways has to be adapted to the shape of the  part. To get it right on first try, you need experience.

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MarkMK - 10/18/2017 11:26:04 AM

If your experience with infusion is limited Steve, I'd concur with Oekmont that pre-preg offers, in theory, a more straightforward process in many ways for a first-time user.

Key with it is to ensure that the fabric is in intimate contact with the mould, to avoid any bridging that results in a rough, pin-holed or broken surface. Before starting, I'd make up lots of cutting templates to take car of the detailed contours on the front. If done tidily, everything will look great even with loads of joins so time put into planning the simplest ways to achieve coverage without need to pull, push and twist the fabric too much will really pay off.

In fact, the trickiest part, unless you're used to making up big envelope bags, will be getting a perfectly sealed bag once everything's laid in. I'd also enlist another pair of hands to help handle any big sections of fabric as it's a pig to deal with in big sections as it just sticks all over the place as you're trying to lay it in.

If you've settled upon this route, then put your effort into designing the mould so that, where possible, you'll be releasing it directly away from the part rather than relying on things coming out at an angle or needing to be flexed. This will, hopefully, guide you on where best to create the parting lines.