Railroad speeders.
https://diqn32j8nouaz.cloudfront.net...r_fullsize.jpg
https://diqn32j8nouaz.cloudfront.net...1_fullsize.jpg
https://diqn32j8nouaz.cloudfront.net...2_fullsize.jpg
Previously:
https://www.homemadetools.net/forum/...032#post168307
https://www.homemadetools.net/forum/...646#post104908
https://www.homemadetools.net/forum/...229#post145964
https://www.homemadetools.net/forum/...976#post137677
https://www.homemadetools.net/forum/...539#post166667
