windows
I have a brand new window and it seems like it could slide a little smoother if it had some lubricant in the rails. It does open fine but it feels like it could be broken in more.
Is there any lubricant I can use in the rails to make it slide better?
Is it DIYable? Yes. No. Maybe?
You may find that you start the job, everything works out just right, and you complete the work in record time and under budget. More likely, you'll run into a bunch of unforeseen problems, take 5 times as long as you'd expect, and end up way over budget.
The best way to tackle DIY work that you are not sure about, is to have the resources available to quickly fix mistakes. In your situation, it might be a good idea to purchase a replacement window before you begin. If you damage the old window beyond repair, you'll simply have to install the new one. On the other hand, if the repair works out, you can return the new window you purchased.
It also never hurts to have somebody with knowledge in the type of work you're doing, so if you run into trouble they can offer guidance.
If you come across something you are really not comfortable with, there are always professionals available to do the work for you. You might also be surprised that they charge less than you might think (not always the case, but does happen).
The usual approach is a "crank-type" casement window with a loop in place of the crank handle, and a hook on a pole (try "clerestory pole crank" as a search term) that engages the loop. There are also hex-type versions that use a flexible shaft inside the pole. Or, these days, motors. I'd suggest the hook on a pole, I view motors in this sort of application as things likely to fail and then make the motorized windows useless as they will probably be hard to replace when they fail. Or they'll leave you with inoperable windows during a power outage.... But it is an option.
A hook or hex style operator pole (image from BlaineWindow.com):
I can't make out how the current windows are operated - they might be able to be retrofitted with operators of that type, rather than replacing the whole window, if the only reason for replacing them would be to make them operable from below.
The style that @TDHofstetter mentions, with a catch that's operable by a hook (image from calaifornia-classics.com):
Best Answer
Usually silicone is good for this kind of thing, doesn't make a mess, screw up wood finish, gum up plastics and rubber, etc. A little goes a long way. Just a tiny squirt on the rails, work it up and down a few times, wipe off any excess.
On older wood on wood windows, wax works very well, in a pinch, or if you don't have any wax, rubbing soap on it.