video tutorial on different solvents and thinners
This video, from ZH Fabrications on YouTube, breaks down the differences between all of the similarly-packaged but extremely different solvents and thinners that are commonly available and seen in every home shop, famously branded by Klean Strip and packaged in same-sized metal containers. In the fine tradition of home DIYers, you've probably used the wrong thinner or solvent before. :)
ZH Fabrications is based at ZHFabrications.com. There is also an accompanying downloadable reference chart available for free here.
https://www.youtube.com/watch?v=ChIhKIGaYeE
Klean Strip does have their own guides (here and here), but this video and reference chart is a nice accompaniment.