I find this is the most extreme when your extrusion volume is excessive, normally due to filament and drive variations.
When your extrusion volume is correct then there's usually no scrape, but what does happen is that the nozzle wipes a bit of material into the print that causes a line in the print (particularly in the cases where you might be printing at higher temperatures).
I find the most problematic issue this causes is that the head pressure builds up if the overextrusion continues, because it means that the extruder drive has to slip to compensate. The actual scrape is usually not a problem though, normally the sprung bed takes up any movement that's necessary to let the nozzle pass.
You can try Slic3r too, that has the option to move the head up on travels. But beware that this is also followed by the head pressure drop and results in extra ooze (which in slic3r you can configure to have a retraction before this). Also in comparison to Cura, I find slic3r very aggressive on retracting, which has caused me many a problem with filament grinding previously when I ran the stock filament pinch thing (versus my current sprung pinch roller).
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codemaven 0
I'm not sure about Cura, but in NetFabb you can make the bed lower on jumps... However, it's more trouble than it's worth. The head does scrape across the top of your last printed layer, but I've never had it damage anything. It makes a noticeable path in the surface when it does, but this is usually on internal layers that you won't see in the end result. You might have some unavoidable jumps on the top surface with some models, but again I've never had any issues with this and have not found it to cause any serious cosmetic problems on the top.
Cheers,
Troy.
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