Wood – use lag screws, lag bolts to hang swing vertically from a wood beam

A good lube is beeswax. It lubes the screw, but does not retain moisture. I have also been known to use a stick type of teflon, used for lubing drawer guides. Or a chunk of paraffin is fine too.

You don't want to add water, so spit is a poor idea. Why encourage the screw to rust???? This is the same reason why soap works poorly. Soap is hydrophilic. Soap actually draws moisture to the screw, causing it to rust away prematurely, so a BAAAADDDDDD idea.

Drilling a pilot hole is often a help, but don't make the hole too fat, or the threads won't bite. I'll often go considerably smaller than the root diameter of the screw. Just a small pilot hole is often adequate in wood, unless one is working in a very hard wood.

Finally, if a screwdriver fails, I often resort to a brace, a hand held drill from the antique bins. Just check a hex bit into the drill and off you go. Even better, I keep my brace fitted with a quick connect for 1/4 inch hex bits always at hand.

I keep one of these tools always on the wall of my shop. It will drive a screw quickly into wood, with enough force to twist the head off most screws if I overdo it. But you also have perfect control over the torque. And the nice thing is, the battery never dies, it needs no extension cord.

It is highly likely that your beams are made of pressure treated wood. If so, you should try to use the same type of wood in repairing them.

SHIM - When there is a slight gap between a beam and a joist, that can often be cured with shims, slim pieces of wood (preferably of the same type, or if not available, a rot resistant type such as cedar). Shims should be forced in (tapped in with a hammer) so they are tight. Often you can drive shims from opposite sides. Since they are tapered, opposing shims can make a tight level gap filler.

LEVEL - If you cannot shim them adequately and need to move the joists to meet the beams, you need to make sure they remain reasonably level. They may have a slight pitch down away from the house, and that would be ok. You do not want to cause them to shift so that they slope toward the house. In some circumstances, that could lead to a drainage problem.

FILL - The holes in the beams can be filled with slivers of pressure treated wood that are coated with exterior glue. Force several narrow wedges in to pack the holes. Let the glue dry and then saw or chisel the surface flat. You can then drill new holes even close to the old ones.