SBS4DCC N Scale F4W-KP Flat KP Mount Wheel Wiper

This listing is for (1) sheet of unformed N-Scale Freight Truck Pick-Ups. The sheet includes (8) F4W-KP Freight Truck Pick-Ups. The F4W-KP has been designed to work with Micro-Trains, Atlas, Intermountain and similar four wheel trucks used on N-Scale freight cars. They are designed to fit trucks with 0.405 inch wheel center spacing and use a 0.138 diameter mounting hole. They also have a lug with a 0.018 diameter hole for thru-hole mounting of the decoder or other wire leads. This hole size is appropriate for 28ga to 34ga wire as used on most decoders. The contacts are made from photo-etched phosphor-bronze and are shipped flat.

The parts in this listing require just a bit of secondary processing before they are ready for use. First, they must be formed into shape. This can be accomplished using a variety of tools ranging from a pair of pliers to a Micro-Mark 16101 Mini Bending Brake. Your choice. Second, and completely optional, heat-treat the parts by baking in the oven at 500F for 1 hour. This will help them retain their shape over time.

All models of N-Scale contacts come in two sizes, 4-40 or KP.  The difference between the 4-40 and the KP version is the size of the mounting hole. The 4-40 has a slightly smaller mounting hole that matches the size of the screw to help keep it centered on the mounting hole. This is important to minimize the chance of a short circuit resulting from the solder tabs touching each other if the contacts become mis-aligned. The standard king pin mount can be used with the KP version but requires a larger washer (if using the SBS KP Hardware Kit) that must be trimmed to allow for necessary clearances. It does not require any modification to the car bolster to install. The 4-40 mount can utilize a smaller washer (if using the SBS 4-40 Hardware Kit) but requires the bolster to be drilled and tapped for a 4-40 screw. Using a 4-40 screw to mount the truck provides greater accuracy in controlling how freely the truck pivots on the car body. I prefer the 4-40 mount over the King Pin because it is adjustable and that's why I offer it.

Collecting track power from your trucks has never been easier. First remove the trucks from your project and car and replace the plastic wheels sets with metal wheel sets that are insulated on one side. Next, simply drill out the kingpin hole in your frame using the #43 drill and tap it for #4-40 threads. Then drill a second hole behind the frame bolster to feed wires from inside the car body to the truck contacts. Feed the wires through the hole and solder the red and black track power leads from any DCC decoder to the lug on the truck contacts. Next, place an insulating washer (or other non-conductive material) between the contacts. Then, secure the contacts and truck to the frame with a 4-40 nylon screw. Last, install a set of metal wheel sets in the truck and make sure they are isolated by checking for continuity between wheels with a multi-meter. Finally. A clean and easy way to power a decoder using track power in your freight and passenger cars. YEAH! No more batteries.

This product is perfect for use in making sound cars and for adding interior lighting to your models. They offer the reliability of 8-wheel pick-up. Best of all, since they are track powered, we now have the ability to add function decoders to our cars to control interior and marker lights. Place a resistor across the contacts and they can be used instead of resistance wheel sets to trigger DCC signal detection devices like the NCE BD20. The uses for this contact are endless. Have fun!