# Box Joint Basics - How wide is a finger?



## wbh1963 (Oct 11, 2011)

Hi Gang,

I spent a good portion of today scouring the net for information on classic 'box joints'.

Most write-ups covered the basics of how to cut them out with a simple table saw sled/jig. Only 3 out of about 20 said anything about finger width/spacing.

A finger width equal to half the thickness of the boards was the low end of what I found. The other two suggested it should be 'about' the same as the board's thickness.

So my question for those that have 'cooked up their own plan' involving box joints is how wide did you make the fingers and what led you to make that decision.

Thanks in advance!


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## LexB (Apr 12, 2010)

The more fingers, the more glue surface area so it's stronger. I choose finger width based on what I have available to cut the slots with--diameter of router bit, etc. There's also the aesthetic consideration--I really like the look of narrow fingers, so I've sometimes used a standard saw blade to cut fingers 1/8-inch. I used 1/4-inch fingers on a box made from 3/4-inch plywood, but the box was ultimately painted so it wasn't done for aesthetic reasons as much as increased glue area. (Those boxes were supports to raise up a front-loading washer and dryer.)

I usually use an Incra fence for box joints, and their pattern book also includes variable-spacing box joints. I haven't tried those, and I doubt that I will because I really like the look of "standard" box joints. I prefer them over machine-cut dovetails for appearance sake. Some of the old Greene & Greene furniture used large finger box joints that were also pinned with a dowel, both for appearance and strength (because the very large fingers used weren't very strong by themselves.) That doesn't appeal to me--just throwing it out there.

When you stop and think about it a box joint is just a through dovetail joint with no slope on the "tails", so there's no reason you couldn't use variable spacing on box joints just like on dovetails. You'd need to cut either the "tail" board first and use it to mark the "pins", or vice-versa (same as with dovetails). I can see where it would be easier than handcut dovetails if you used a dado stack on a table saw to do the cutting.


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## Mike (Nov 22, 2004)

Bill, it really depends on the project. The largest I have seen were the 1" wide box joints on a waterbed frame. For most boxes you can't beat the Oak Park box joint jigs.


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## zarpman (Oct 30, 2011)

Bill, I invested in a box joint blade setup by Freud that can cut 1/4'' and 3/8'' joints. The blade turns back to back and front to front to make the different withs. Blade makes extreamly smooth cuts and is used with a box joint jig on my table saw. usually I make the cuts the thickness of the work piece. When making small drawers for desks etc. I plane down wood to 3/8'' on my planner and box joint for a good looking drawer. I tried my router however; my result was not as good (probably me and my setup or dull bit) I cannot remember the name of blade and I am in my office now but I will look in my shop latter and see what itis. Good Luck zarpman Melbourne, Fl.


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## wbh1963 (Oct 11, 2011)

Lex,

Thanks for putting so much energy and thought into your response. The variety of 'considerations' you brought up is excellent and a great example of the many things I think about when trying to make 'design decisions' as a newbie to planning wood working projects from scratch. I seldom remember 'every' angle when thinking through an idea, so it is a real treat to have the benefit of another craftsman's 'checklist'.



LexB said:


> .... The more fingers, the more glue surface area so it's stronger....


Using glue is a 'new frontier for me. I did however finally pick up my first bottle of wood glue recently so that I can ease into it. One thing that concerns me about using glue with finger/box joints is how much space should be left so the joint doesn't end up weak from starvation. I am searching for the patience to do some 'test runs' with scrap stock before actually glueing up some of my 'in progress' boxes.




LexB said:


> .... I choose finger width based on what I have available to cut the slots with--diameter of router bit, etc.


It's so nice to hear I am not the only one that re-writes a design to synchronize it with whatever is already in the 'tool box'!



LexB said:


> .... There's also the aesthetic consideration--I really like the look of narrow fingers, so I've sometimes used a standard saw blade to cut fingers 1/8-inch.





LexB said:


> .....I usually use an Incra fence for box joints, and their pattern book also includes variable-spacing box joints. I haven't tried those, and I doubt that I will because I really like the look of "standard" box joints.....


My 'OCD' mentality not only demands 'same-size' fingers for the joint, it is highly resistant to a 'partial' finger at the board edge when the board width is not evenly divisible by the finger width.



LexB said:


> .... Some of the old Greene & Greene furniture used large finger box joints that were also pinned with a dowel ....


I have thought about trying to do something like that with pin stock through fingers as small as 1/2". I just havent figured out how to drill a hole that is as small as 1/16th to 1/8th through a 5-10" inch row of fingers.




LexB said:


> You'd need to cut either the "tail" board first and use it to mark the "pins", or vice-versa (same as with dovetails). I can see where it would be easier than handcut dovetails if you used a dado stack on a table saw to do the cutting.


I am perpetually adjusting my understanding of when it is better to 'hand cut' something than go through the hassle of setting up a 'powered cut'

Thanks again Lex


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## wbh1963 (Oct 11, 2011)

Mike said:


> Bill, it really depends on the project. The largest I have seen were the 1" wide box joints on a waterbed frame. For most boxes you can't beat the Oak Park box joint jigs.


The OP brand name does have a following here, so much so there must be sound reasons so many people choose it. Rebuilding my Bed is one of many pending projects I have on hold until I get a lot more functional with box jointing. Given my idea of a space efficient bed is a lot more like a cabinet a open shelf large enough for me to stretch out in, the number and type joints are a lot more numerous than a typical bed.

Thanks for the tip (OP recommendation)


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## wbh1963 (Oct 11, 2011)

zarpman said:


> Bill, I invested in a box joint blade setup by Freud that can cut 1/4'' and 3/8'' joints. The blade turns back to back and front to front to make the different withs. Blade makes extreamly smooth cuts and is used with a box joint jig on my table saw. usually I make the cuts the thickness of the work piece. When making small drawers for desks etc. I plane down wood to 3/8'' on my planner and box joint for a good looking drawer. I tried my router however; my result was not as good (probably me and my setup or dull bit) I cannot remember the name of blade and I am in my office now but I will look in my shop latter and see what itis. Good Luck zarpman Melbourne, Fl.


Lou,

The box joint blade from Freud sounds very interesting. I look forward to learning more about that product. My urge to build lots of boxes of different shapes and sizes, especially considering my tendency to go for the 'least expensive' when buying materials is pushing me to pick up a thickness planer of some sort. A couple questions beyond the model number for the Freud blade come to mind in reaction to your comment.

I'm interested in any brand specific or technique comments you might have on selecting and using a planer to process material when building boxes.

Did you make your own jig for use on a table saw or are you using a 'commercially produced one".?


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## zarpman (Oct 30, 2011)

Bill, I use a manufactured one that I bought from Rockler but you can build one yourself that will work just as good. ther are plenty of plans for them on the internet.I just saw a video from Leigh Tool Co. that makes a dovetail jig and a box joint jig all in one (R9 plus)that can be used on a router table or set it up on your bench. I think it sells for $149.99 ouch! it looked and seemed to be a good tool.The blade is Freud SBOX8 for 1/4'' and 3/8'' joints. Have fun and be carefull zarpman Melbourne, Fl.


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## bobj3 (Jan 17, 2006)

Hi

the easy way for BIG box joints almost any size, by kp91

Router Forums - View Single Post - Best way to set up a jig for LARGE finger/box joints?

==


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## wbh1963 (Oct 11, 2011)

Thanks for the rapid follow up with the model number. That set is so cool I just had to, had to include a quick-link to the sbox8 page on the the Freud site.

One of the things I am currently fighting with my TS is the reality of having gone too close to the bottom of the food chain when selecting it. Many of the low end saws don't have 'real' T tracks in the table. The slot is 5/8" wide front to back. Then at to places front to back about a half inch long section of the table extends over the track narrowing the gap for that inch to 7/16". The bottom line is that the material sliding through the track needs to be tee shaped itself. Tool selection definitely has a learning curve.


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## wbh1963 (Oct 11, 2011)

Thanks again bob!


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## LexB (Apr 12, 2010)

wbh1963 said:


> Lex,
> 
> 
> 
> ...


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## Cuemaker (May 14, 2011)

*woodgears.ca*

I use the following box joint jig and it works beautifully..... here is where to go...

woodgears.ca


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