The Corsair site is interesting. Amazing what people can do when they put their mind to it.
RTM is a little more complex than it appears. It allows you to dry position the fiber cloth in position with the fibers in the direction and layers required for the part. By doing so the part can be 'tuned' to have reinforcement in specific places or strength in specific directions or different fibers (glass & carbon ) in different places. You cannot do this with a chopped strand wet mix for example, and the weight and strengths would be very different.
For more complex or engineered parts the rtm trick is to get the resin to flow throughout the part evenly and in the quantity and time required. If you just inject resin at one point and vacuum from another then spme of the part will not get impregnated. Even when the part is fully impregnated you have to adjust the injection and vaccum scheme to ensure that the ratio of resin to fiber is as required across the part accounting for the amount of fiber and the shape of the part. The benefit is that once it's worked out you can produce a huge number of identical parts with identical mechanical characteristics with minimal material wastage.
As Gerry suggested I'd think that for the sort of parts a hobbiest is likely to make then a 'super' home vaccum bagging system with a bit of trial and error sounds possible.  |