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Old 07-10-10, 09:50 PM   #1
C-daleRider
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28.6-31.6 Seat Post Shim

Hey Just wondering if anybody new how to make one because apparently they aren't availbale to purchase? p.s. I want to make sure it's reliable and safe thanks.
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Old 07-10-10, 10:58 PM   #2
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1.5 mm thick shim stock .. that is the difference between the 2 , rolling it around the post = 3mm ,
the diameter difference in question..
Vernier Micrometer caliper is useful in measuring these sort of thin materials..
wall thickness of a tube is a radial measurement .. 2r=D
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Old 07-10-10, 11:04 PM   #3
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http://wheelsmfg.com/content/view/529/41/

why don't you just buy a 31.6 seatpost? They exist, thomson et al. 28.6 is also another unusual size.

Pre-manufactured shim will take a 31.6 to a much more common 27.2 size. Do that.
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Old 07-11-10, 01:20 AM   #4
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Quote:
Originally Posted by fietsbob View Post
1.5 mm thick shim stock .. that is the difference between the 2 , rolling it around the post = 3mm ,
the diameter difference in question..
Vernier Micrometer caliper is useful in measuring these sort of thin materials..
wall thickness of a tube is a radial measurement .. 2r=D
Thanks fietbob for the lightening quick response and the helpful insights, I read that aluminum is the best matrial to use for this. Any advice on how to get the shim formed?
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http://wheelsmfg.com/content/view/529/41/

why don't you just buy a 31.6 seatpost? They exist, thomson et al. 28.6 is also another unusual size.

Pre-manufactured shim will take a 31.6 to a much more common 27.2 size. Do that.
Thats true that regular post exist, but suspension seat posts in a 31.6 dia. don't(with the possible exception of an awful looking device called a thud buster but it still might haved to be shimmed up). I want a suspension seat post that's as close the the diameter as possible. When I purchased my bike I was naive and thought suspension seat posts were availble in all sizes. p.s. a 27.2 looks like a tooth pick when coming out of a 31.6 tube.
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Old 07-11-10, 01:29 AM   #5
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p.s. a 27.2 looks like a tooth pick when coming out of a 31.6 tube.
This requirement makes no sense. Aesthetically a suspension post in of itself is a fail already
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Old 07-11-10, 02:10 AM   #6
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No requirement, and there are different levels of ugly. Doing this for comfort/health reasons only.
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