Usually these routines allow you to only do 2-4 exercises for arms (as they only prescribe 2-4 sets for bis and tris). Do you mix it up a lot or stick to the same ones?
@kennethe62 I don't mix it up much but only because I've never had a huge need to. For bi my favs are chin ups and regular barbell curls. For tri I like skullcrushers and close grip bench. Instead of mixing up the movements I usually do something like drop sets or double rest pause sets (i think thats what they're called).
One final note:
these routines allow you to only do 2-4 exercises for arms
@kennethe62 I think the best route to take regardless of muscle group is pick only a handful of exercises and rotate every couple mesocycles if you wish. Most of the progress seen when you start a new movement is simply developing the skill to perform that movement more effectively and until you develop this skill you're not going to be able to provide a sufficient growth stimulus. So there is certainly a disadvantage to switching things up too much, but there are also advantages to getting a bit of exercise variety.
Since something like a bicep curl or tricep extension is a much simpler movement pattern than say a squat, the time needed to develop this skill is much lower and movements can generally be rotated more frequently. Personally I would stay with the same movement for at least 4 weeks before rotating and really only rotate if you've hit a wall with your current movements or just need something different out of boredom.
My favorite for movements are pretty much the same as /@brendan3248. Currently I'm rotating between preacher machine curl + bayesian curl for biceps, and overhead cable extension + v-bar pushdown for triceps.
I use two bicep moves 2x a week every mesocycle. Every meso (month), I pick two new bicep moves and use them the whole month. This allows for a reduction in adaptive resistance and a growth of all parts of the muscle.
@kennethe62 I just keep it simple and stick to the same ones. It's hard to track progress if you are constantly changing exercises, range of motion, tempo, and all that jazz. Barbell curls, dips, chins, and overhead triceps extensions.
@kennethe62 My two cents - very similar to what folks have already said, but when it comes to switching things up for me it's either after one deload (6-8 weeks) or two if I'm still progressing on that particular lift. For instance, I had been doing Incline DB curls for about 12 weeks (2 deloads) and have now switched onto Preacher Curls using an EZ curl bar.