I picked up the violin last year!

I'm a guitar player but wanted to experiment with the violin, so, I bought one.
It isn't too difficult. After a week, (playing about 8 hours a day) I started to get sounds that weren't
too horrible, and believe me, the sounds you're going to get are going to be horrible at first.
I guess they key is to be able to deal with repetitive exercises. With the guitar, I just played the scales over and over again, non-stop, for hours at a time. If there was a chord I couldn't hold right, I'd keep my hand in that position till it went numb (usually about an hour or two). When I was learning drums, I built my leg muscle for the bass drum by tapping my foot non-stop (again, hours at a time while watching TV or something). So, with the violin, I just I kept going back and forth with the bow or playing the scales (that I managed to figure out).
I quit though because I was afraid that if I ended up teaching myself incorrectly, it would be hard to turn back. In the end though, I did manage to learn some songs by ear.
LowRider, Angel in The Center Fold.... stupid songs (well, LowRider is actually cool

).
So, it's not hard to start playing some songs pretty quickly if you have guitar experience. Not having frets isn't so bad, after all, if you can play guitar with your eyes closed, it's kind of the same thing. The tricky thing is that fact that it's so small! You don't have move your fingers nearly as much as you would think you would. In fact, there's almost no gap between your fingers (and I have small hands) when you lay them out on the 'fret board' (I forget what it's called).
Another reason why I quit was the fact that there aren't as many resourced for violin as there are for guitar. For example, I never found any forums, and forums are great when you want to ask something.
One thing though, I doubt you’ll be able to master it if you’re also trying to master guitar, which is another reason why I let it go. You might end up spreading yourself too thin. Still, it wouldn’t be bad to learn a little bit and be able to play some jigs.
