Kerf Maker Box Joints #1: Easy Box Joints - How To

  • Advertise with us
Blog entry by George_SA posted 02-12-2018 03:12 PM 1873 reads 1 time favorited 1 comment Add to Favorites Watch
no previous part Part 1 of Kerf Maker Box Joints series Part 2: Making uneven Box Joints »

EDIT 13 Mar 2018
Part 2 explains it more clearly and works for even spaced and uneven spaced fingers.

While thinking about making a joint that is similar to making Box Joints, I came up with the idea to use my
5 Minute Kerf maker and Small Sled to make Box Joints.

It works like this
You use a stop block and spacers and the Kerf Maker on the sled to cut the Box Joint Fingers.

The 1st step is to align everything for the 1st cut.

I switched the spacers and the Kerf Maker around to save my Kerf Maker from getting chewed up by my saw blade. In a perfect world that shouldn’t happen, but alas in the real world it does. The spacers are expendable and therefore it is not a problem if the spacer gets chewed up a bit.

The 2nd step is to make the 1st cut

The 3rd step is to remove a spacer, flip the Kerf Maker and make the 2nd cut

In the following illustration I try to explain why you need to use a Kerf Maker and why it must be flipped after every cut.

The Kerf Maker is used to take the blade thickness into account when making the cuts. If you just use spacers without the Kerf Maker, then the cuts would be out by the thickness of the blade every time.

The 4th step is to remove another spacer and flip the Kerf Maker again to make allowance for the blade thickness and then do the 3rd cut

The 5th step is to remove another spacer and again flip the Kerf Maker and to make the 4th cut

The last step is to nibble out the waste

The above steps describe the procedure to make 2 fingers. If you need to make more fingers, just repeat steps 2 and 3 for every additional finger and make sure that you have enough spacers for the amount of fingers that you want to cut. The amount of spacers = the amount of fingers – 1.

If you need to cut out a waste finger offset from the side then do the setup as in step 1. Then WITHOUT flipping the Kerf Maker remove a spacer before doing the 1st cut. Thereafter proceed with steps 2 and 3 as described above. (See illustration below)

It might seem complicated at first, but basically it boils down to aligning the work piece using a stop block, Kerf Maker and spacers. Then you just need to remove a spacer and flip the Kerf Maker for every finger that you want to cut.

The result is a box joint that is just as good, if not better than box joints cut on one of my other jigs.

A good tight fit.

Just a word of CAUTION! Make sure that you DON’T cut your own fingers while cutting the Box Joint fingers!!!! If you feel uncomfortable with this technique then DON’T DO IT!!!!!!

Even if you don’t use this technique for making box joints, this blog hopefully explains the principle of how a Kerf Maker works.

Thanks for taking a look.

-- Sometimes life gets in the way of one's woodworking :)

1 comment so far

View observer100's profile


476 posts in 2230 days

#1 posted 02-12-2018 06:49 PM

I see what is going on now … very nice. Very simple yet somewhat hard to understand without studying your nice diagrams a few times.

-- Seeing is believing.

Have your say...

You must be signed in to post the comments.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics