This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
A convenient paper smoother and penwiper can be easily made as follows: Procure a common celluloid harness ring, A, about 1 1/2in. in diameter and fasten a penwiper, B, to it. The wiper is made of arts-crafts leather, doubled and filled with pieces of chamois. They are held in place with a ribbon or cord tied as shown. The roughened paper caused by erasing can be easily smoothed with the ring. - Contributed by G. H. Holter, Jasper, Minn.