Seeing your disk has a bolt and nut as the hinge you probably are able to take it appart again. I very much suggest to add a free pointer to the angle,speed,range, time side to help in crossing the speed/range scales to the time scale. But make it long enough to cross the whole disk anyway.
To easily calculate distances over times longer than an hour I first calculate the distance travelled in one hour for a certain speed. That is at the 6 minutes mark ( as it is the same mark as 60 minutes) on the time disk if the fixed pointer of the time disk is pointing to the speed. The distance travelled for times upto 2 hours 40 minutes can be found at each mark if you add a 0 to the value at the mark and read that as the amount of minutes passed.
But how about longer than that?
Keeping the free pointer on the distance value that was against the 6 minute/hour mark, I then rotate the timedisk until the 1-00/10 mark (1 minute, 10 minutes, ...they are all the same) is under the free pointer. (the fixed speed pointer shows a bogus speed now, don't pay attention to that anymore) Now looking at the distances along the edge of the time disk, you see the distances that are travelled during 2 hours upto 16 hours. They also have appropriate 10 minute subdivisions.
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