Hey everyone,
I've been reading this thread, and IMO most great guitar players don't play solos using scales. They play around a scale of course, and they may also play some parts of it. Great solos are made up of riffs, and licks using a scale, or some of the notes from it. I do play out of the pentatonic scale, but very seldom do I play the scale itself. I know it, but I add hammer ons, pull offs, and a bend or two to make it interesting. I may do some slides too, or maybe play a triplet, or a double stop.

Maybe you have practiced the scale enough, try doing the same thing in a different way using some of the techniques I mentioned. Instead of 3 notes only hit 2 on the top 4 strings, and then a whole step bend on the 3rd string or something.

I'm assuming you guys are referring to rock, and I've played my share of that too. I still play some AC/DC, Skynyrd, Kansas, Bad Company, Van Halen, or Stevie Ray, and many others whenever it's requested. I know the signatures to these songs, but I don't always play them. I might play the sigs the first time around, and then throw in my licks. My suggestion to you, is to add to, or take away from the scales you practice when you think about solos. Open strings are also a great way to get around the fretboard, and also playing out of chord positions.

If you really want to improvise your own solos, you need to learn more riffs, and licks. Knowing scales is important, because that lets you know which notes will work, and where to put them. However when you practice your scales, don't be afraid to embellish them some with more than just speed. You will end up in the same place, but there's more than 1 way to get there. More playing techniques, and a few licks can go a long way when improvising a solo. Best of luck to you, and I hope you'll give it a try.