53097

Need a finish for Surface Friction on stainless spacers [Tennessee] 

September 14, 2009

I need to increase the surface friction between a stack of stainless spacers. I am applying a compression force to the stack and relying on surface friction to hold them. I have called out a sand blast finish but this quickly became smooth and allowed the spacers to move. I also need to maintain a tolerance of .005 on the thickness of the spacers. Any suggestions for a repeatable finish specification?

George Fowler
designer - Jackson, Tennessee

If sand blast did not work, you might try a knurled-fine -finish and have it on the high side so that you would eventually end up on the low side as it wore down.
Are "star" washers a possibility??

James Watts
- FL

Heavy compression causes twinning of the metal. This makes the material stronger,but also smoother.

Annealing them will soften them up, and provide you with a bit more friction.

If you can choose another metal, I would lean towards aluminum or an aluminum coating. The coefficient of friction between two pieces of raw aluminum is greater than one.

Robert H Kinner
- Toledo, OH