
Vaseline is what I have heard recommended before, together with nice thick padded soft beds.
I have used surgical spirit before on my finger tips to harden them for playing stringed musical instruments -- but not sure if that would work the same on calluses - I think it works on foot pads - and it would also sting if they are sore. Sorry, not much help, really.
If they are sore and inflamed you could try aloe vera to soothe them. :)