Kerfmaker made simple

  • Advertise with us
Project by SPalm posted 07-27-2009 04:05 PM 11315 views 90 times favorited 22 comments Add to Favorites Watch

After seeing treeman’s excellent project of creating a Kerfmaker, I knew I had to have one. I did not really want to spend the required time right now to build his version, so I decided to reduce it down to the simplest required parts.

The main requirement is to have a sliding and locking bar that includes the width of a saw blade. I decided to make the saw width permanent because I usually use the same blade for doing this type of work. By having this a permanent thickness for the gauge, the build becomes half as easy. (Twice as easy?)

Creating a locking and sliding bar set was the next challenge. I really did not want to have to route a groove, so I made an overlapping ledge that will be pinched to form the lock. A bolt, large washers, and a T-nut created to locking mechanism.

The build took very little time. It is around 5 inches long. I used 3/4 inch stock with 1/4 inch top. I oversized the top pieces, glued them to the stock, and used the belt sander to clean them up. A one inch long 1/4 inch bolt was used for the lock. I inset the T-nut a little off center to maximise the clamping surface. The lock is very strong with a slight twist of a wrench. I nice knob here would be a good improvement, but heh.

To compensate for the exact width of the blade, I came up with a technique. Cut both sticks to the same length by closing the device all the way shut. Cross cut through both sticks to make them flush. Now the stick without the end piece on it needs to be reduced by a saw thickness. Clamp and cut a piece of scrap on the right hand side of a miter gauge. Slide this stick right up to this scrap and cut. Exactly one thickness will be removed.

Good luck,

-- -- I'm no rocket surgeon

22 comments so far

View PurpLev's profile


8476 posts in 2491 days

#1 posted 07-27-2009 04:17 PM

1. glad to see a new post from you… :)

2. this is a fantastic jig. thanks for introducing it again for those of us that missed the previous posts about it. definitely something that should be in any shop. added to my never ending list.

-- ㊍ When in doubt - There is no doubt - Go the safer route.

View BeachedBones's profile


201 posts in 2245 days

#2 posted 07-27-2009 04:18 PM

Nice and simple, maybe even simple enough for me to try.

You could probably make a couple of these for your different thickness blades. You’d just have to keep them marked somehow so you don’t mix them up.

-- You know.... I think that old wood needs to be furniture.

View CharlieM1958's profile


15907 posts in 3061 days

#3 posted 07-27-2009 04:31 PM

Steve, I saw the original post, and you have done a great job of simplifying the build. Now I just have to go back and watch the video. I can intuitively see the point of this, but am still not quite visualizing exactly how it works. LOL!

-- Charlie M. "Woodworking - patience = firewood"

View treeman's profile


208 posts in 2292 days

#4 posted 07-27-2009 04:51 PM

Looks simple enough you could make one for every groove cutter you have.

Charlie M.,

This geometry will explain how it works.

View Greg Wurst's profile

Greg Wurst

783 posts in 2675 days

#5 posted 07-27-2009 04:54 PM

Wow, I have to build one of these now. Quick, simple, and effective.

-- You're a unique and special person, just like everyone else.

View Kent Shepherd's profile

Kent Shepherd

2698 posts in 2129 days

#6 posted 07-27-2009 06:31 PM


-- She thought I hung the moon--now she just thinks I did it wrong

View SimonSKL's profile


184 posts in 2082 days

#7 posted 07-27-2009 06:46 PM

Until I see this post I didn’t even know what a Kerfmaker is. This is ingenious! Thanks for simplifying this clever device to make it doable at my skill level. That will be my next project.

-- Simon, Danville, IL

View David65's profile


190 posts in 2128 days

#8 posted 07-27-2009 07:34 PM

Very nicely done I like it.

-- David '65

View reggiek's profile


2240 posts in 2113 days

#9 posted 07-27-2009 08:08 PM

Now we see real LJ’s….we will buy no tools that we can make! I like the idea and certainly will join in the que to get one made….I like the simplicity here…although Treeman’s was very nice too…

I am currently working on another jig I want to use for making segmented/staved vessels…soon as that is done I should have some spare hardwood for this…

Thanks for taking the hard parts and breaking them down for us…NICE JOB.

-- Woodworking.....My small slice of heaven!

View Karson's profile


34940 posts in 3243 days

#10 posted 07-27-2009 08:14 PM

Great job Steve.

-- I've been blessed with a father who liked to tinker in wood, and a wife who lets me tinker in wood. Southern Delaware †

View Mike Gager's profile

Mike Gager

642 posts in 2110 days

#11 posted 07-27-2009 09:28 PM

am i the only one that doesnt get what this is supposed to do? :-/

View SPalm's profile


5062 posts in 2725 days

#12 posted 07-27-2009 09:36 PM

Thanks everyone.

It is a jig for easy control of the width of the groove for inserting various thicknesses of cross pieces. These width of these grooves are usually just cut by trial and error. The best thing to do is probably to view the video at Bridge City.


-- -- I'm no rocket surgeon

View Lee A. Jesberger's profile

Lee A. Jesberger

6757 posts in 2822 days

#13 posted 07-28-2009 01:07 AM

HI Steve;

Too bad they don’t have a workbench. Then they could stop beating on their saw table!

Nice little jig.

Very handy.


-- by Lee A. Jesberger

View John Stegall's profile

John Stegall

433 posts in 2359 days

#14 posted 07-28-2009 01:19 AM

I now use a Delta 745 and I really do not want to overload the motor by using a dado blade. At least this will allow me to see if I can get satisfactory results w/o using the dado. Thanks to treeman bringing this to our attention and SPalm for this simple way of making one. At first I wondered if it needed to be made out of aluminum or brass, but I think I have a piece of mesquite that needs to be made into one of these.

-- jstegall

View blackcherry's profile


3212 posts in 2666 days

#15 posted 07-28-2009 01:29 AM

Hey Steve, nice job on your design, it looks like a handy and useful tool. Thanks for sharing…Blkcherry

showing 1 through 15 of 22 comments

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