I am having a problem on setting up timing of events in my PD patch.

What I need is to play "Sine osc~" for 5 seconds, and then a "Saw osc~" for 5 seconds, not playing them both at the same time but interchangeably.
It would be nice if I could repeat this for ever too.

Can anyone help to make this in my patch?
I am stuck and it seams like a simple problem.

there are several ways to do that
here the first that came in my mind

http://www.pdpatchrepo.info/hurleur/tws.pd

here's alistair's patch, with signals for the sine and saw

http://www.pdpatchrepo.info/hurleur/tws-withSignals.pd

Thank you very much, this help a lot. I can see the pattern here.
I created a small patch simulating the proposed behavior.

Now the last problem is that I don't want to always play the [osc~] for n milliseconds, but as a composition, first part 500 ms, than 2000 ms, than 200 ms, and so on.

How can I specify a list of intervals (e.g. 500, 2000, 200, ...), which will control the [metro], which actually controls the [osc~]'s?

give a look at [metro], [metroplus], [delay] and [clock] they can be your friends

Thank you very much, [metroplus] was exactly what I needed.