Make your own shim:...
 

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[Closed] Make your own shim: 31.6 - 30.9

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 Olly
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Strikes me that the difference of 0.7mm, between 30.9 and 31.6, isn't worth spending nearly tenner on a seat post shim for?
I've just mocked up a shim from a sheet of 0.5mm, and obviously it's too snug (total 1mm), but I was able to make it nice and long, and was also able to cut it with a Stanley knife.
Anyone running a pikey seat post shim?
Any suggestions as to a source of 0.35mm sheet i might find around the house this evening?

Piston head cans are 0.01mm
Might try a Hob goblin next.
Beans for tea?
They make them out of plastic too, don't they?


 
Posted : 26/12/2019 8:23 pm
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Given my experience with shims and posts slipping I'd stick with your thick one and thin it down somehow (wet and dry? ).


 
Posted : 26/12/2019 8:28 pm
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One word:

Coke can


 
Posted : 26/12/2019 8:32 pm
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Coke can is two words.

Spoon, now that's a single word.


 
Posted : 26/12/2019 8:40 pm
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Whack it with a hammer until it is the required thinness


 
Posted : 26/12/2019 8:47 pm
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I run a shim on my surly, it’s a USE one, made of plastic.
Doesn’t slip or anything, well worth a tenner imo.
https://ultimateuse.com/spares-and-accessories/seatpost-shims/30-9mm-i-d-shim


 
Posted : 26/12/2019 8:58 pm
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I ran a cut-up can of Tennents lager as a shim, for 31.6 to 30.9, for about 5 years. I wouldn’t spend money on a shim for this purpose, but I a a cheapskate.


 
Posted : 26/12/2019 9:01 pm
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Use hammer, carefully, on existing shim to achieve required thickness/thin-ness; soft-faced if you have one.
Alternatively, use granny's mangle.
HTH


 
Posted : 26/12/2019 9:33 pm
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Lindab galvanised steel guttering downpipe worked a treat for me. Ever so slightly thick for a full wrap. Probably a gap of 15mm or so.


 
Posted : 26/12/2019 9:58 pm
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Strikes me that the difference of 0.7mm, between 30.9 and 31.6, isn’t worth spending nearly tenner on a seat post shim for

If it makes the post fit the frame, it's worth it. I have used drink can shims plenty though, they're just a bit fiddly. Fine if you fit the post permanently, PITA if you need to raise and lower it frequently.


 
Posted : 26/12/2019 10:24 pm
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Why are you questioning the value based on shim thickness? If you need the right tool for the job, a ten quid shim's a ten quid shim, regardless of thickness.


 
Posted : 27/12/2019 5:35 am
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35 years of riding MTB. Tried coke can shims a couple of times but that was 20 years ago. Ok to try on a cheap frame and post to get it working, maybe on a commuter for example, but just buy the right shim on anything else. Your frame and post will thank you for it.

Small tip - if you want to make sure a post is supported longer than a normal shin then buy 2 shims and grind off the lip on one and mount it lower down. A small dab of glue helps to keep it there if you ever want to pull it out without the shin dropping down the seat tube. Useful for bikes with longer sections of seat tube above the top tube


 
Posted : 27/12/2019 9:00 am
Posts: 20675
 

Some people value their time differently I guess


 
Posted : 27/12/2019 9:02 am

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