Tokina 500mm Mirror Lens Focus Seized-up

I've had a Tokina 500mm Mirror Lens for a while, but it's not been used for a couple of years. I got it out to try it with my K3-3, but the focus has seized solid. - I can't move the barrel at all. The lens has been in a drawer since last used, so it's not been dropped or otherwise abused.

Anyone know what could have happened? Does anyone have disassembly instructions so I can have a go at fixing it?

Thanks for the info. I'll give it a go.

Any luck?

smc

Thank you for taking the time and trouble to follow-up.

I found more detailed information about dismantling the lens on the Pentaxforums website and managed to take it apart sufficiently to gain access to the helical thread. There, I applied heat from my wife's hairdryer, which persuaded the thread to move, albeit rather stiffly. I have applied some silicon gease, hopefully to prevents it seizing up again, so hopefully it's fixed.

Regards