Already it is not so easy to align the two rails accurately and without moving the rails, tighten the joints, since of it is not accessible (below).
Then you have to position the rails together not only in terms of alignment, but also parallax. Indeed the connection parts have lateral play in their housing.
We must tighten strong enough pieces for the rails does not disrupt. This does not mark the lack of rails are aluminum.
In short, not so easy to end up with a large perfectly straight rail. Or a long reliable straight cut, which can be trusted, that's usually what you search using a saw track.
It takes 2 connectors for joining two rails, and the price is given by unité.Le price ultimately very high compared to the service is deplorable ... to be sure of the result, it is better a large rail in one piece .
