I am repairing a guard rail for a deck, can Kwikwood putty be counted on after filling in the old screw hole to hold the new screw safely?
According to the manufacturer's web site, it should be strong enough. But personally, I would be wary and, if possible without too much trouble, I would either add an additional screw (and bracket, etc. if needed) a few inches away or move the existing screw (and bracket, etc.) a few inches away from the original screw location.