Happy New Year Everyone!
Thank you for your Excellent suggestions.
In regards to 4" screws, I was working with a stair stringer and needed to drive a 2 x 4" (width) into the stringer (9.5" width) and figured that a longer screw would be better. Did try the countersink bits without much luck. Looking back, perhaps, a lag screw would have been a wiser option. The link you sent has been educational. Because of the pixs, I can now see and relate to what is available for what.
Liquid soap! Got to try this one. When we say square head, that is different from Torx which seems to have a "star" shaped head...? Correct? I take it that they are for exterior usage? Thank you.
Is the square bit you are referring to similar to the one Hammerman is referring to? Is composite also what they call MDF? Thank you.
Here are other things I tried with the results:
1. Used electric 1/2" 800rpm power drill with manual chuck and side handle - same results with existing screws. Better results with more expensive Philips (Mustard colored exterior) screws though the ***** store did not carry 4" and had to use 3".
2. Used a boring bit (1/4") to create a "countersink" hole wide enough to let my extended screw holder attachment with the screw slide in and then applied sufficient downward force. Decent results thus far... cannot understand why it worked...but, desperation sometimes leads to "creative" solutions.