How best to remove stuck screws?

[braggscowboy]

I bought an old National Cash Register (brass) and it has been sitting somewhere where it drawed dampness and the strews that hold the wood bottom to the brass are definitly can not get them with a screw driver. I have from time to time used the screw removers from Craftsman with no luck. Does anyone out there have a tried and true method to remove a screw? In this case, several of them. I might work a hacksaw blade under them to cut the screw, but then I am stuck on how to remove the screws from the brass. Wondering if I might drill new holes and tap? Any ideas would be appreciated. Thanks!

[Wiste]

For stuck screws you could try a penetrating oil unless you're saying the heads are stripped. If the metal isn't too brittle you could drill and tap. You could also try a helicoil insert which seems easier to to me than trying to tap perfect threads.

[Iddee]

!... Soak with brake fluid, wait 24 hours.

2... Soak with penetrating oil, wait 24 hours.

3... While pressing down hard and turning with screwdriver, hit screwdriver handle repeatedly with hammer.

The hammering while turning works as an impact wrench and will work the screw loose within 2 to 3 minutes of hammering.

Patience is of the utmost importance when using this method, but it works.

[braggscowboy]

Thanks, I have tried the penetrating oil, but have not tried the patience.
Will try it. I also tried the tapping of screw driver. Have not tried the brake fluid idea. Thanks!

[suitcase_sally]

Can you heat the screws?