Hi,
my have not the same length after some modelling. Tried the LoopTools space tool, but this works only on connected edges. Is there a non manuell way to set the edges to the same lenght?
Yes, Like Omar says, in this case I'd leave it as it is now.
There is however a handy Addon, Edit Mesh Tools:

That allows you to do this:

Moin,
thanks. Unfortually the Set Edge Length only works with not connected vertices (edges with shared vertices are not allowed). As I'm trying to model the spikes on the knobs the distance of the vertices do matter. But it is as it is. I'll do it manually. And the Set Edge Length is still helpful. Thanks for mentioned the tool.