If it is beyond a tug and it is frozen, then I always take 2 things away as a learning curve. 1. My maintenance routine is not cutting it - I need to lift my game. Look at what I have used on the slides, and review that performance as well. 2. The cost to get it fixed by my Tech is the cost of my laziness. Why would I risk damage to one of my horns? The Tech has the skills, he is worth the visit. Chemical Clean/ Ultrasonic/ Hammer? I don't care, he will make that decision - it is not my stress to worry about it, just invest in how to avoid it.