Up until now I have had minimal issues with the Kato Unitrack #4 switch when occasionally used for industry spurs and have not bothered to tweak them. My latest track plan however uses pinwheel ladders in the double ended switching yard and in two large industry yards. This arrangement of #4 switches has become a deadly combination resulting in perpetual derailments when entering the switches from the leading point direction. I first looked over the published technique of filing a notch in the rails for the point rails to set into and quickly realized that was going to be a long and tedious job, however if done correctly it does work very well. I also discovered that the travel of the point(s) is limited by the slot underneath the points that guide the point rails in conjunction with the plastic clip (joiner). As part of this modification you must also elongate this slot; otherwise the point(s) will not come to rest against the contact rail. I told myself there must be a better way. What I realized was a better way was also the easiest way. I decided to file the lead edge of each point to a dull knife edge (about half the thickness of the original point rail thickness). I file on the inside of the point rail and taper out to 3/16 inch. Never file on the point rail contact side or you will end up with a gap between the point rail and contact rail unless you also elongate the aforementioned slot. My finishing touch is to deburr the lead edge of the point rail by gently filing the lead edge using the steepest angle possible. I then check each switch position with the point rail against the rail in contact by running a fingernail across the inside of the rails. If it grabs the fingernail it needs more work. I am now running various length diesel powered (four and six axle and consisted) trains and every type of rolling stock through different combinations of modified switches at all speeds without any derailments. The newer Kato switches use shiny stainless steel for the point rails and do not bend under pressure; older Kato switches with dull point rails are less forgiving to pressure. I have not tested this method using steam locos. I also want to point out that neither technique is a cure all for all causes of derailments. I’m thrilled with the results and hope others can benefit from my success. Jerry
Secondary issue with the Kato Unitrack #4 switch As I see it the main issue with the #4 switch is picking the points. You can either bury the points in the rails or file them down to a knife edge. When you choose to bury them in the rails is when you must also elongate the slot; otherwise they will still have a tendency to hang out far enough to be picked. Another secondary issue with the #4 switches lies at the other end of the point rails where they meet with the rails leading to the frog. I have had to knock off the inside point on the rail head with a file to prevent picking the rail head. If you try to bend the point rail to the inside you risk breakage of the brass clips or spreading of the point rail retaining flanges and changing the alignment of the point rail at the point end (not recommended). Run your finger through the inside of the rail path in both directions with the switch in the open and closed positions. If you encounter a snag then you have located a potential picking issue. Jerry
