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Need a finish for Surface Friction on stainless spacers
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 Fowlerdesigner - Jackson, Tennessee
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September 16, 2009
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?
- Navarre, Florida
September 25, 2009
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.
- Toledo, Ohio