Bronze Bushing

• 5/16" ID for Universal Axis - 3/4" long - [1] - $1.58. 0.09 cubic inch volume - bronze is 0.3 lb per cubic inch - so each bearing is 0.03 lb.
• 3D printing - 1/2 lb of bronze filamet is $45. For the above 3/4" bushings - only 18 can be printed - so about $3 each.
• If we reduce the length to 1/4" - we get down to $75 cents per bushing - comparable to the 50 cent price of linear ball bearings from China