Make a Cast Iron Straight Edge for £20
Here's a quick video for you where I share my idea of using a Stanley No.5 woodworking plane as a poor man's straight edge.
A while back I needed to hand scrape my metal lathe bed flat and didn't have a precision straight edge to check it for flatness. As it happened I had recently hand scraped my jackplane flat to within about 0.0002" and it made the perfect substitute for a proper purpose made straight edge.
I always enjoy improvising and saving a few quid, so I hope you find this idea useful!
Handy Links
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Carbide Hand Scrapers - https://ebay.us/uKTQmc
Carbide Scraper Inserts - https://ebay.us/FZUxmO
Engineers Blue - https://amzn.to/3XoBMSM
Rubber Roller - https://ebay.us/RMBsyo
Surface Plate - https://ebay.us/2yrNIh
Slip Stone - https://amzn.to/4d8aJB8