The food dehydrator works very well for getting oil out of a ball. Previous to that I used the hot water method of sweating out oil in several balls and that worked very well, too; however, I didn't have much success keeping water out of the holes. That's why I went to the hot air method instead.
Like I said before, I seldom use the dehydrator these days.
The three worst balls for soaking up oil for me were:
1 Track 300T, 2 Storm Vivid and 3 Storm Hy-Road.
The traction of the 300T and Vivid diminished drastically, but the Hy-Road was still working quite well although it had a lot of absorbed lane oil.
For several years now I might start up the dehydrator perhaps once a year or so just to check things out. I guess my shammy and ball cleaning methods are working well.
I've learned in the last couple of years that certain balls are best with factory finish and others that I have require changes to either remove the polish or compound finish or to go to a little rougher grit finish to get the reaction working well.
For example, I bought my first Hammer ball (Dark Legend hybrid) which had their Clean n'Sheen finish. I tried several changes to that ball and finally took the Clean n'Sheen off along with sanding it with 2000 grit, 3000 grit and then 4000 grit pads. Next time out it was like a different ball. Before that I was quite disappointed.