Hi,

This is a pretty thick infusion. What exactly are your problems? What is your layup schedule? Can you post pictures?

> 1. Should the flow media cover cover the entire laminate or should it only cover a part of it? Should it be in contact with the outlet spiral as well?

Only when you use something called "MTI tube" should the flow media contact the outlet spiral, otherwise you might end up sucking too much resin into your catch pot. Use a break zone made from peel ply, this will slow down the resin enough so it has time to fully saturate the fabric before it reaches the outlet spiral. People have had success without a break zone, but it depends on many factors whether this works reliably or not.

> 2. The flow on the top is much faster than at the bottom due to the flow media. Is there anything I can do to speed up the flow at the bottom surface?

This is to be expected. The resin will saturate the fabrics from top down.

Is the resin you use suitable for infusion? What is its viscosity and its pot life? Being vinylester it contains volatile components that will outgas (evaporate) under vacuum. This reduces the effective vacuum in your bag.
If the resin viscosity is too high it travels too slowly and takes too long to saturate the laminate.

Post pictures and the name of the resin if that's possible.

This ^

Use a slower infusion mesh, I've seen 25thk laminates successfully infused (although not tried it myself), it's all about matching the right speed infusion mesh, resin viscosity and gel time, stack sequence and dam length between the end of the mesh and the vacuum outlet to allow the bottom of the flow front to catch up with the top

You are definitely towards the limit of infusion in terms of thickness.  You ideally would need something with a long pot life and infuse it really slowly, ie mm's per minute as you need the time to allow the resin to soak through to the bottom.

You might find that wet-lay vacuum bagging is more successful in the long run as you can wet it all out layer by layer then reduce the weight and improve resin/fibre ratio and compression with the vacuum bagging.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant