REPLACING CARBON ROLLERS

Unplug the transformer!

First remove the 2 metal handles.
Then remove the nut on top that secures the on/off switch to the case.
Then remove the rear plate (2 screws).
Tip the unit upside down, and remove the 4 screws that hold the base to the case.
You can now lift and tip the case out of the way, being careful not to break any wires, or bend any of the copper throttle parts.
Clean the top of the coil with a little Radio Shack Contact Cleaner (non-flammable) on a tissue. This will remove most of the old carbon residue.
    NOTE: Avoid other brands of contact cleaner ! Nearly all of them are highly flammable, and damaging to plastic. Radio Shack's brand is neither ! A little pricey----but safe !
Inspect the cord for breaks or cracks. Replace if necessary.

The old rollers are probably secured with short peened rivets.
Snip one end with cotters, and remove/discard the old pins and rollers.
Insert a new roller, and secure it with a cotter pin which I supply.  (Cotter pins are easier to install than rivets.)
If this is a double-handle transformer, such as an 18B or 30B, insert the cotter pins so that the straight tips are toward each other.
     If inserted with the “heads” toward each other, there is a possibility of them touching each other when both handles are at mid-throttle.
Bend the cotter pin tips vertical and flat, and then snip off the excess length.
Repeat with the 2^nd roller, if there are two.

Re-assemble, first lowering the case downward onto the coil, and making sure that the roller assemblies engage the control levers on the knobs.

Then, before replacing all the base screws, put the handles back on the knobs, and make sure that the rollers contact the coil when the handles are locked down, but do not touch the coils when the handles are lifted.  If necessary, you may have to slightly bend the copper arms to which the rollers are attached…..but be gentle doing so (they can snap).

Once you have proper adjustment, complete the reassembly.