On Wed, 9 Dec 2015 13:18:56 +0800
800L wrote:

snip
Have you looked at buying them off the shelf? They used to be much
cheaper than you could make them for.

Depending on how far you want to space them out:

http://www.amazon.com/s/185-8990793-... heel%20spacer

$6.50 for 1/4 inch to $130 for a pair of 3 inch.

At least the original poster can see some pictures of how it is being
done commercially...

--
Leon Fisk
Grand Rapids MI/Zone 5b
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