Originally Posted by Gigalot
Add Cobalt drier instead of Liquin.
I will second that. You only need to add a tiny bit of CoZiCa or some other dryer to your existing paints to speed up the drying process. I bought the CoZiCa because it was less expensive than other brands and it works as advertised. That being said it might not take much alkyd medium to speed up the drying. If you already have some alkyd medium, test it and see.
If you do end up getting some CoZiCa or something like it, I would recommend using a solvent resistant dropper bottle to dispense it in predictable drop sizes and only add as much as is needed without going over the maximum recommended. Test always before using in a painting.
The red caps as shown in the photo, work better for me than the clear silicone caps. The clear ones break too easily, causing leakage in my plein air kit plus the ones I have do not seal well between the screw on cap and the bottle. I have to put some teflon tape on the threads to get a tight seal. I would not recommend getting that style. The black cap / red top cap design also has replaceable needles which is a better setup than the other style, but they will cost you more. Regardless of which you use, keep them in a water tight bag or container in case they do leak. If you can find them, get a set with a solid screw on cap as well as the needle tipped cap for a more secure seal when traveling.