Hi all, I started playing with composites about a year ago & have learnt a bit since then. All of these parts have been for micro light aircraft. The latest pieces I'm trying to produce are 10mm x 45mm x 405mm bars. My first attempt was just a simple layup sandwedged between 2 molds. The results were that it weighs the same as an aluminium equivalent. So the only way to improve on this would be to do a vacuum infusion.
I made a vacuum pump that pulls about 26Hg max, Is this enough?
How can I insure that the carbon tow is fully saturated at the bottom of the mold?

 The mold is "C" channel & I don't plan on using the second half on the mold.

The first time I did a wet layup & sandwedged it between the two molds using clamps, no vacuum. I was trying to get a nice finish on all four sides. Some resin was removed but still had a very high resin to fiber content and was full of pin holes. I put as much CF in the mold as I could fit in being wet. It was about 13mm thick when cured. I had to tighten the clamps in stages or the hole lot would squeeze out the end like a tube of tooth paste.

To get a thinner dimension (10mm) under vacuum I have about twice as much CF as the first attempt.
Do you think it would help if I put the resin flow mat on both sides (top & bottom) and maybe sandwedge some  resin in the middle?