How to fit the TSC25 stainless-steel guide pin to your

1/24 or 1/32 scale
chassis

The TSR chassis and cars were primarily designed to be driven on the German Carrera plastic track. When used on some other plastic or wood tracks that have very narrow slots, the plastic guide blade fitted to the earlier issues of the TSR chassis has a tendency to bind in the slot when the chassis reaches its maximum drift angle. This causes a jerky reaction that can have detrimental effects in the car's handling that include interruption in electrical contact, possible electrical short and possible breakage of the guide blade.

 

The installation of this metal pin now supplied in all TSR kits and RTR models will greatly improve your car's behavior while awaiting the future TSR2 chassis that will have a rotating guide of advanced design and be fully compatible with all other existing chassis parts.

 

IMPORTANT: Read this first:

For use on Carrera or Artin tracks as well as on any and all vintage American-built tracks such as Revell, Aurora, Atlas, Monogram, as well as most routed wood tracks, no alteration of the steel pin itself is necessary, but careful fitment of the braided contacts as shown below is a must for best performance.
 

To obtain the best of your TSR chassis when used on Scalextric "Classic", Ninco or any track featuring a shallow and narrow slot, this guide pin MUST be shortened by 1.5mm or a bit over 1/16". Use a Dremel disk or grind the end of the pin on a disk or belt sander while holding the steel pin in a pin-vise or a pair of Maun parallel pliers. The guide pin is made of very hard stainless steel, do not attempt to use a saw to shorten this pin. For use on Ninco track, once fitted to the chassis, a small amount of each side of the pin must be flattened with a Dremel disk so as to clear the extremely narrow slot.

 

  For use on Scalextric "Sport" track: make sure to make the following modifications to your power base: the slot depth on the power base where the connecting wires cross the track is not as deep as on the rest of the track, tripping longer guides that otherwise clear the other track elements. You will need to unscrew the cover under the track and cut away the parts shown in the picture (see above the large "A" and on bottom right) so as to allow the wires extra clearance. Use a wooden or plastic tongue depressor placed in the slot to gently push the wires down and out of the way, being careful not to cut into their insulation.

We have also discovered that the width of the
Scalextric "Sport" track slot is very inconsistent, the guide pin sometimes binding in parts of the track where the steel rails have been improperly assembled, but easily clearing the rails just a few inches further... If the guide pin binds in some track pieces, again use a tongue depressor to gently ease the rails where they should have been in the first place.

 

 

1/ Steel guide pin basic installation on older chassis with plastic guide blade:

 

 

 

  The steel guide pin is machined with a taper, meaning that only the bottom of the pin will actually contact the slot. It will fit most plastic and wood tracks with the limitations indicated above. The shape of the center hex matches that of the original guide-retaining nut.
Assemble the chassis as per instructions and set it to the desired wheelbase for the selected body, position A, B or C on the chassis and 1, 2 or 3 on the front axle. Mount the body and make sure that everything is free and clear.
Next, remove the body, and with diagonal cutting pliers, cut off the guide blade at the base of the chassis as shown. There is no need to remove the braided contacts to perform this operation when using cutting pliers.

 

 

For a basic installation, the steel pin merely replaces the original guide-retaining bolt and uses its retaining nut. Just push in place from the bottom of the chassis, through the braided contacts retainer and the steel pan stop, and use the 2-56 nut on top of the pin. Tighten with a 3/16" socket. Done!

NOTE: If using the chassis in its longest wheelbase (position C) , make SURE to use the black plastic washer shown below that is supplied with your RTR or chassis kit:
 

Cut the washer at the end of the sprue:  

 

You may also use a small 3/32" steel washer instead. Set the washer on top of the guide pin, then fit the retaining nut as otherwise you will run short of threads and your guide will not apply sufficient pressure between the braided contacts and the lead wires. Use a 3/16" socket on a socker handle to firmly tighten the pin.

 

   

For use on Ninco track or any track with either narrow or inconsistant slot width dictated by steel rails directly in contact with the guide, you will need to shave a "flat" on each side of the steel pin guide with a Dremel disc. In the case of Ninco track, the slot is not only narrower but a lot shallower, so the length of the pin must be shortened by a full 1/16"...

For use on Scalextric or similar track where the rails are so close together as they line up the slot, gently form the braided contacts so that they converge towards each other while maintaining at least 1/8" clearance. Make sure that the contacts are totally flat and resting on the chassis, with their ends gently curved down and frayed to improve contact.

For use on any other track, plastic or wood, just leave the brushes parallel and as flat as possible on the chassis with the ends very slightly curved towards the track. Never the opposite! Only the ENDS of the contacts must touch the track rails.

 

 

2/ Optimum installation:

 

  This installation is best to keep optimum electrical contact during on-track drifting, especially when not using a traction magnet. For best results and trouble-free operation, it is essential to mount the pin in the center of the braided contacts. This requires that the chassis be drilled and the hole gently counter sunk to provide clearance for the pin's center hex. Install the original plastic guide blade first and trim the blade as described above. Precisely drill a .086" hole (drill # 44) and countersink with a 1/4" drill of which end has been bround flat. Ideally, a step drill should be used, and it is critical to mill only 1/16" deep. Be careful not to drill any deeper as you would drill through the chassis as this would be terminal...

For those who do not believe that they have the necessary skills to perform this delicate surgery, all TSR spare chassis are now available with this upgrade, part # T2401 or T3201.

 

 

Proceed as in step # 1 above. Now you are left with a complete chassis and a severed guide blade:

    Next, using an X-Acto fitted with a # 11 blade, mark a clear spot for your drill exactly in the center of the severed guide blade. Rotate several times to make sure that the drill will not slip off the blade.

 

 

Ideally, a step drill ( .086" to .250") should be used for the next operation. However, not everyone has the facilities to grind one. Our staff made this one by hand, grinding a standard 1/4" drill bit with a Dremel disk down to .086" on a length of 3/8".

For most mortals, just use a # 44 drill bit, if possible set in a drill press, and drill a hole right through the severed guide blade and the steel pan spacer (part TSC04), that is if you chassis is set in wheelbase position A or B.

 

Now comes the delicate part: the hex-shaped part of the steel pin MUST be recessed into the chassis to clear the contacts and the track. So counter-sinking is absolutely essential, but the chassis in this area is very thin. Best would be to grind the end of a 1/4" drill flat, and VERY GENTLY, mill a .065" cavity in which the hex will fit. Easy with a step drill, not so easy with a loose drill... Patience is essential to avoid drilling through the chassis, which effectively would force you to revert to installation # 1. If you did well, this is how it will look. Now all you have to do is to remove any burrs with the X-Acto knife and install the pin by simply pushing it from the bottom of the chassis.

 

 

  You will need an extra 2-56 nut (TSC06) to secure the new guide. This is how the whole assembly should look like once drilled. A small brass or steel washer may be added but is not necessary. However, if your chassis is set in wheelbase position C and thus, not using the T-shaped spacer, it is IMPERATIVE that you use the washer supplied with your car. The reason? If not, you will run out of threads, and there will not be enough pressure on the braided contacts, and no current will flow to the motor...

 

  Final setup: for Scalextric or similar tracks fitted with narrow rails, gently curve the contacts inwards as described in paragraph 1. Have no fear of a possible short, the contacts are working at different levels and are far enough from the metal hex and the pin itself, and it is virtually impossible for them to touch each other or even the pin while racing. Don't forget to shorten and shave the guide pin sides if the car is to be used on Ninco or the old Scalextric "Classic" tracks. No such problems for any other tracks.

For standard tracks (all others except Scalextric clones), just keep the braided contacts parallel to each other.

 

  Once fitted, this is how it should look. Now your TSRF pocket-rocket is ready to rock and will be able to negotiate the tightest curves without current interruption. All TSR RTR cars are sold with all these modifications already performed, so no worry if you decide to purchase an assembled car.!

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