The question about necessary length of the guide rail.

[Mihail_Lazarev]

I want to buy a guide rail for my Dewalt DCS 576. Ideally, I plan to have two parts of the guide rail, to fold them, to cut a plywood with a length of 2.44 m.

Since I'm a newbie and just started working as a carpenter, I still learn everything, I do not really know what I need, so I decided to ask the following:
Now it seems to me that it makes no sense to have two identical 1.5m guide rails. Because they are quite long for most works and work with them is not convenient.

But if one part is 1m., and the other is 1.5m., It will be much better, because I can use short one small cuts, and at the same time both of them should be enough for a sheet long 2.44m.

Am I right or do I have an error in my thinking?

I'm afraid that 2.5 meters of the guide rail may not be enough for a sheet of plywood.

[Job and Knock]

You need to take into account the length of the baseplate of your saw as it will need to be supported at the start and end of the cut as well as during the cut. So, if your saw baseplate is 160mm long and you want to cut 2440mm material with a non-plunge saw you'd need a minimum of approximately 2440 + 160 + 80 = 2680mm of rail length. With a non-plunge saw you'd need almost a full baseplate length overhand at the start of the cut, but you only need to support the saw at the end of the cut up to the half way point (i.e. the point where the saw is at maximum depth of cut). With a plunging saw you can reduce that by approximately 1/2 the length of the base plate at the start of the cut giving a rail requirement of approximately 2440 + 80 + 80 = 2600mm. If you run the saw off the end of the guide rail a lot you will wear-out the base plate of the saw eventually - believe me, I know!