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Expansive Bit Care and Maintenance

Shop for Expansive bits

A custom wet stone for sharpening the lip and spur of an expansive bit Expansive bits should not require a lot of specialist care. They are sturdy tools that should last a long time, so the main cost involved in keeping them spick and span will be in creating a custom wet stone for sharpening.

For more information on wet stones, see {{widget type=”cms/widget_page_link” anchor_text=”How to sharpen an expansive bit” title=”How to sharpen an expansive bit” template=”cms/widget/link/link_inline.phtml” page_id=”3246″}}

Image showing an example of a dry place; expansive bits must be kept dry to prevent them from rusting As well as keeping your expansive bits sharp, you must also keep them dry.
An antique expansive bit - these tools are now rare Allowing your tools to rust seriously decreases their life and undoes all your hard work sharpening your bit.

Mind the gap!

Close up of the head of a clark patent expansive bit showing the clasp adjuster mechanism In a Clark-patent expansive bit, the cutter should be flush against the back of the tool when it is screwed into place by the lock screw.

For more information on this type of bit, see: {{widget type=”cms/widget_page_link” anchor_text=”What are the different types of expansive bit?” title=”What are the different types of expansive bit?” template=”cms/widget/link/link_inline.phtml” page_id=”3238″}}

Wood shavings created by an expansive bit that can become stuck behind the adjustable cutter If it is not, wood shavings could get stuck in the gap between the tool and the cutter, causing it to clog.
Slide out the cutter you are changing to make a space for the new cutter If, for any reason, your cutter is not flush against the body of your bit, remove it, and check if there is any debris stuck in the tool.
DIYer filing the back of an adjustable cutter for an expansive bit so that it will sit flush inside the locking mechanism If everything seems clear, you will need to file the back of your cutter to make sure it is flat. You can do this with with a flat file, an abrasive tool designed to smooth down metal surfaces, being careful not to take any material off the curved cutting lip or the bottom of the bit.

For more information on flat files, see: {{widget type=”cms/widget_page_link” anchor_text=”Files” title=”Files” template=”cms/widget/link/link_inline.phtml” page_id=”2348″}}

Image of an adjustable cutter from an expansive bit It’s better to file down the cutter rather than the bit itself, as it may be that your spare cutter still fits perfectly. If you filed down the body, your first cutter would fit again, but your second cutter would now be the wrong shape – you would be trading one duff cutter for another!