by Bob Ward
Good electrical contact with the track is vital to the performance of any slot car. In this article you will learn how to make sure your cars’ pickup braid makes and maintains the best possible contact.
A common beginner’s question is, “How and when do I change the braid on my new race set cars?” New slot car hobbyists also ask if the braid and lead wires are glued into the guide. Also, because the guide, braid, and lead wires are often sold as a unit in some manufacturers’ spare parts selections some newcomers initially assume they have to be replaced that way. We’re pleased to assure everyone that the braid can be replaced quickly and easily on all the cars we sell and that in virtually all cases it’s a toolless process.
Ninco, Fly, Slot It, NSR, and many other makers of 1:32 scale plastic-chassis RTR cars use the guide design shown above. The braids are inserted in vertical slots and small ferrule-type connectors on the ends of the lead wires press-fit into adjacent holes. When the ferrule is pressed into its hole it jams the braid against the inside of the guide, firmly holding both lead wire and braid in place in the guide.
To replace the braid, first pull the guide down out of its socket so it hangs by the lead wires. Be careful not to pull the lead wires out. Then, pull one lead wire and ferrule out of the top of the guide and pull the braid downward through the bottom of the guide. Slide the new braid downward through the top of the guide until about 1/16” of it remains above the top of the guide. Bend that 1/16”of braid back over the top of the guide and press the lead wire, with its ferrule connector, back into the top of the guide. Bend the braid back along the bottom of the guide and adjust it for proper contact with the track. It should be bent down far enough to make solid, positive contact but should not exert enough pressure to lift the front end of the car. Repeat the procedure on the other side, snap the guide post back into its socket, and you’re back to racing. You should have only one lead wire disconnected at any time. This assures that you will always get each lead wire plugged into the same side of the guide and your car will always run in the same direction.
Older Scalextric cars and SCX cars use a “wireless” electrical system, in which no wires go into the guide. Instead, each of the two extra-long braids wraps around the top of the guide and metal shoes on the bottom of the chassis make contact with them. Both Scalextric and SCX sell packages of guides already made up with braid on them. To change braid, just snap the guide down out of its socket in the chassis and snap a new one, with new braid, back in. This is about as user-friendly as you can get. The Scalextric and SCX braid setup are shown below.
You can modify your Scalextric cars’ braid to the SCX configuration for improved electrical contact. Get a 1m length of copper braid. VLH carries several brands to choose from. Cut off two 1.25” (32mm) lengths of braid Remove the steel braid from your Scalextric guide by sliding it out sideways. Then, just wrap the new braid over the guide and bend it as shown below and you have better braid with both ends touching the track for increased contact area and better conductivity.
More recent Scalextric cars use the “braid plate” guide design, in which the main portion of the guide remains in place on the car and a plastic disc holding both braids snaps into place. The procedure for changing braid on these cars is shown below. You just slide the braid plate forward, lift up the front edge of it, slide it back over the guide blade, and it’s off. Installing the new braid plate, with new braid on it, simply reverses the procedure.
Over time the guide can wear where the braid plate slides in and out until the plate is no longer a tight fit in the guide. Then the braid plate will come loose and fall out in a crash. At that point the guide needs to be replaced.
Pioneer Models equips its cars with its own unique guide design. The guide has an extra-long post. This allows it to be pulled down below the chassis for braid changes without detaching it from the car.
The braid comes with a brass clip on the end that presses into the front of the guide in the same manner as the braid used in the venerable Jet Guide that has been universal in 1/24 scale commercial track racing for decades.
Changing braid is simply a matter of pulling the old braid out of the front of the guide and pressing the new ones in. Then push the guide back up into the running position and you’re ready to race. You never need to remove the lead wires from the guide while changing braid.
In addition to keeping fresh braid on your cars you also need to be sure the braid is kept clean and adjusted properly for positive contact with the track and proper alignment with the track’s contact strips. Slot car braid is made from flat braided wire, either steel or copper, which has a certain amount of “spring” to it. The spring action allows the braid to maintain positive contact with the metal strips in the track as the car moves. The object in adjusting the braid is to bend the braid downward from the bottom of the guide just enough to give it positive contact without putting so much tension on it that it tends to lever the front of the car upward, lifting the guide partially out of the slot and degrading the car’s handling.
In the drawing above, #1 shows the correct way to bend the braid, down just far enough to make good contact. #2 shows the braid bend down too far, and #3 shows the braid flat against the bottom of the guide, where it may not contact the track at all. To get just the right braid adjustment on any individual car may require a little trial and error, but with experience you will learn to get just the right tension on the braid quickly and easily every time. The same principle applies to braid on all types and makes of slot car whether they have single or double braids. With use, braid eventually loses its spring and will no longer maintain positive contact. When this happens you will need to replace it.
In addition to being adjusted up and down for correct tension the braid also must have the proper alignment. #1 above shows proper side-to-side alignment of the braid. The braid is directly over the track strips and makes contact with their full width. #2 shows the braid splayed outward and not making good contact with the track strips. It’s also important that the braid not be allowed to develop a twist that leaves it with only the inner or outer edge contacting the track strips. #3 shows the braid making even contact with the track strips across its entire width for maximum power and performance as well as consistent contact. #4 shows the braid twisted so that either the inner or outer edge is making contact with the track.
Along with proper adjustment you will need to keep the braid clean. As your cars run the braid accumulates dust, dirt, and other foreign substances from the track. To clean it you can use WD 40 or any of the common braid cleaning products. Be sure to check your braid for proper adjustment after each cleaning.
If you have questions or comments about this article we invite you to e-mail e-mail them to firstname.lastname@example.org or call at (insert phone number here). We’ll be glad to give you all the information and advice you need.
Copyright ©2014 Robert M. Ward. All rights reserved.