Ask WWGOA: Joiner Biscuit Sizes

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Question:

I ordered a Porter Cable biscuit jointer and was wondering what size biscuits to order. How do you determine what size biscuit is used for a particular job. I have read about PC’s FF size but am still confused. Your advice is appreciated.

Submitted by HHolmes

Answer:

The three common biscuit sizes are 0, 10, and 20. You can find these almost anywhere, from home centers to specialty stores. While biscuits are a great joinery solution, they do have a few limitations. One is the length of the slot required to use a biscuit. Even the smallest biscuit, the 0, requires a slot that’s too long to use on the end grain of a 1-1/2″ wide face frame rail. This problem is solved by the FF biscuits. They’re round, instead of football shaped, and require a different cutter. Biscuit joiners typically use a 5″ diameter cutting blade. Some machines, like the Porter Cable 557, allow you to swap to a smaller diameter blade and use the FF biscuits. If your machine doesn’t allow the change to a smaller blade, you can’t use the FF biscuits.

When choosing what biscuit to use, go with the largest biscuit that will work for your application.

George


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6 Responses to “Ask WWGOA: Joiner Biscuit Sizes”

  1. Kevin

    ‬Thanks Paul toward my biscuit jointer question. My jointer does the different sizes, 0, 10, 20 but it's th thickness I an concerned with. My jointer seems to cut thicker then my bicuts are. Comments? Are there thicker biscuits?

  2. gary

    I need 1/2x1inch biscuits

  3. Jim Young

    I recently picked up a used biscuit joiner. When I make a practice cut the physical width of the opening measures .230". What size biscuit do I need for this opening?

  4. Zach

    Can 10 biscuits be used for a 20 sized cut?

  5. Frank

    Rockler makes a handy gauge that shows exactly where the slot will be cut for the 0, 10, and 20 size biscuits. https://www.rockler.com/biscuit-cutter-gauge

  6. Jeff

    A standard biscuit blade is not 5"; it is 4" x 5/32" which is an approximation of the metric size 100 mm x 4 mm. The arbor is 22 mm or 7/8".