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RickKr 03-29-2019 10:09 PM

Gluing Finger Joints
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I've just gotten my Incra LS Positioner set up and in use. First thing I did was clean up the sides of some maple. Really slick how with the Wonder Fence you can take off very small amounts. With the Bosch router table & the fence that came with it, the increments are fixed at 1/16", at least with the spacers that came with it.

I started out wanting to make a finger joint box, just to figure out how the LS works. I have a set of Craftsman chisels that came from my former father-in-law. The box they are in and the plastic cradle/insert appear to be made for the set of chisels, but the box is such crap, I have a hard time believing it was original with the chisel set.

At any rate, I decided to try making a replacement box. Turns out the only router bit I have that can be used with the LS is a 1/4" up cut. So, I selected 1/4" Baltic birch plywood for the box. I was very pleasantly surprised how easy it actually is to make the finger joints using the LS. I've never made any box/finger or dovetail joints before.

New box sides with rabbets for the bottom.

I'm ready to glue these together and put the bottom in, but I am intimidated by having to spread glue on all these small fingers and getting the glue distributed to all the corners in a timely manner without created a huge mess. I'd really like to keep the glue off the sides as much as possible. I have considered clipping the head off of a Q-Tip and using the stub end. I don't want to use a Q-Tip straight as I think cotton threads will get captured. What techniques have you guys used for this sort of glue-up?

I'd like to replace the hardware (hinges and front clasp) but I am having trouble finding much of anything. I've checked Rockler, Woodcraft and MicroMark. MicroMark has some, solid bras, but they seem too small. What suppliers have any of you used for hardware like these?

Thanks for any help.


Cherryville Chuck 03-29-2019 11:39 PM

I agree Rick. I don't think that's the box they came in if they ever came in a box at all as I don't recall much of Sears small tools that were sold that way. Lots of people use a small paint brush for that type glue up. I have some plastic paddles that I got from Lee Valley that are good for spreading a drop or two of glue that you drop onto the surfaces from a glue bottle.You don't want much glue and not much is needed. You also normally only glue the sides of the fingers and not the bottom of the gullets. That helps prevent squeeze out.

This is also a good time to talk about using a glue with enough open time to allow you to get all the surfaces glued and assembled in time. Titebonds 1 and 3 have short open times. T2 has a longer open time and there is also a Titebond Extend which has a longer open time still. If you are well organized you may be okay with one with short open time. You can also consider gluing just 2 sides together at a time and then joining those two halves together after but make sure they are drying square as you proceed to the second step. I often enlist my wife's help in situations where time will be pushed close to the limit.

DesertRatTom 03-30-2019 12:05 AM

6 Attachment(s)
Pretty good so far. One thing you can do is use a slow curing glues as Charles suggested, or one of the brown glues that take hours to cure completely.

I suggest you use a small metal brush Pix below, to apply the glue. These give you pretty good control of the glue. Generally you can wipe off any excess using a damp cloth for a couple of passes on the inside and outside. If you made the fingers a little proud (desirable), you will be using a block plane or sanding to get rid of the excess.

The other challenge is to keep the box square as the glue sets. If the bottom fits tight, you can insert it to help hold it square. Another option is using box joint cauls (pix) and a belt style band clamp (Pix). The cauls stand clear of the slightly proud fingers of your box joints. The picture of the orange band clamp already has a standoff and should work well

You could make your own L shaped cauls on a table saw, adding a strip to each inside edge so they make room for the proud fingers. The L drawing is an end view. Start with a 2 inch square piece. Make certain your saw blade is exactly 90 to the table. Make one cut about 1 3/8ths high, flip the piece and cut the same amount on the other side. Use some aged and seasoned wood so it will stay stable. Glue some strips on the inside edges as shown so they stand clear of the glue. Use a band clamp as shown to hold the box together. Cut the cauls into about 6 inch long sectons and wax the holy crap into the inside so the glue doesn't stick!

You could also use some reliably 90 degree L brackets, clamped with small clamps, into each inside corner. Make sure the brackets don't touch the glue. The second diagram shows how simple it is to make someting to hold corners square on a table saw, using 2 inch square material. Cut square by having the blade be exactly 90 to the table, then make a 45 degree cut as shown. I would use some 4 inch F clamps--five bucks each at Home Depot--see pix. It will take at least 8 clamps for a box like yours. You could use the small Harbor Freight F clamps for this instead, but I like the Bessey clamps better.

Finally, what you have made is a box joint. Finger joints are different. Each finger tapers and they are usually used to glue two short pieces together end to end to produce longer lengths. Many inexpensive items are made from this kind of joint. Because finger joints are tapered and come to a point, they cannot be used for box joints. Just a little woodworking lingo. And here are a couple of links.

There are a lot of ways to glue up box joint boxes, these represent a few that will do the trick for you.

RickKr 03-30-2019 12:17 AM

Thanks for the info, guys. The only wood glue I have is Titebond 3. I have a number of those metal handle brushes. Use them mainly for putting cutting oil on lathe turning/milling/drilling in metal. They seem too large and cumbersome for these 1/4" "box" joints. Thanks for the clarification on finger vs box joints. The bottom does fit tight, enough to use it for keeping things square. I was going to glue it in at the same time.

I recall looking at some of those clamping fixtures at Rockler a couple months back, and thinking "I don't have any need for those..." :smile:


DesertRatTom 03-30-2019 12:31 AM

Really easy to make those cauls, especially the simple one you put on the inside corner. Once you have the tools to make boxes, it seems to trigger a flurry of box making. Great for gifts and only take a weekend. I liked the idea of having the wife help with the glue ups.

Here's a link to the extra long open time Titebond glue. Definitely a good choice. I'm going to order a bottle myself because I'm itching to start using my new Incra Box Joint Jig.

DaninVan 03-30-2019 01:37 AM

Rick; you might find the hinges you need here...
Check out the whole site; especially clock parts and scroll saw blades.

ger21 03-30-2019 07:51 AM

Assemble the box dry, and apply blue painters tape in the corners, on each board. This will keep the inside clean

Then use small brushes like those show above, and glue up. After the glue dries, peel off the tape inside. You may need to run a chisel into the corners if there are any small beads left over.

DesertRatTom 03-30-2019 11:00 AM

You inspired me. Off today to buy some nice figured hardwood to make a fancy box. I already have some invisible hinges, but not sure I'll make a hinged box. May have several available for remembrance boxes for Christmas gifts.

Cherryville Chuck 03-30-2019 11:38 AM


Originally Posted by RickKr (Post 2009059)
They seem too large and cumbersome for these 1/4" "box" joints. Thanks for the clarification on finger vs box joints.


Never make assumptions about which type joint it is. If you do a web search on finger joints about 75% of them come back as "a finger joint also known as a box joint". All of Fine Woodworking's contributors refer to a box joint as a finger joint first. Most of older woodworking literature also refer to it as a finger joint. The tapered fingers were specifically referred to as a tapered finger joint or as a splice joint since that is the only function of that type joint i.e. end joining two boards together. That is the main clue about which type joint is being discussed is whether it is the splicing type or not.

RickKr 03-30-2019 12:17 PM


Originally Posted by DesertRatTom (Post 2009111)
You inspired me. Off today to buy some nice figured hardwood to make a fancy box. I already have some invisible hinges, but not sure I'll make a hinged box. May have several available for remembrance boxes for Christmas gifts.


I'd be interested in info about your invisible hinges. I've been searching various sites for small hinges and am not that satisfied with what I've found - for this particular box.


RickKr 03-30-2019 12:37 PM


Originally Posted by ger21 (Post 2009083)
Assemble the box dry, and apply blue painters tape in the corners, on each board. This will keep the inside clean

Then use small brushes like those show above, and glue up. After the glue dries, peel off the tape inside. You may need to run a chisel into the corners if there are any small beads left over.

Excellent idea. Thanks. I was particularly concerned about getting the glue out from those inside corners.


RickKr 03-30-2019 07:47 PM

Box Glued
6 Attachment(s)
I checked the one open hardware store in my town and the closest other three, 1-hr away and no one had the Titebond Extend. I could not wait to order some, so I went ahead with the TB3.

Worked out great. I trimmed down one of those foam brushes and also an acid brush. I tried the trimmed acid brush, but it put too much glue where I didn't want it. I went with the head-chopped-off-Q-tip. That worked perfectly, getting good amounts glue right where I wanted it, in the joints and not too much.

The glue up went without a hitch. I really appreciate the tip about using painters tape at the corners/edges. There wasn't much glue to wipe up, but what there was, was easy.

The joints came out quite nice, I think. I'm very impressed with the Incra LS Positioner. As stated in their documentation, using their tool/methods on box joints, if they are too loose or too tight (too loose = oversized, too tight = undersized), it is a problem with the bit not the LS. My joints were too tight. I tried shifting the fence a few thou., but that didn't work out. I just cut them regular and worked the joints a bit to get them to fit. I also measured my bit (1/4" Freud spiral upcut). It is 0.244", 0.006" undersized and by about as much as I tried shifting the fence. Still, I need to get a bit that is on size for this cutting.


ger21 03-30-2019 08:02 PM

If the bit is undersize, you need to recut 1 side only of all the joints after offsetting the fence the needed amount.

RickKr 03-30-2019 08:06 PM


Originally Posted by ger21 (Post 2009189)
If the bit is undersize, you need to recut 1 side only of all the joints after offsetting the fence the needed amount.

Thanks. I tried that. It means offsetting for each stack and I think that is were I got off-track, keeping track.


Cherryville Chuck 03-30-2019 10:50 PM

I make a sanding aid that would help you with that Rick. I take scrap high pressure counter top laminate (Formica to you) and cut it into rectangular pieces about 1 1/2 to 2" wide by 3 to 5" long and I glue sandpaper to the back side of them, usually 80 grit. Because they are thin and stiff it would allow you to take a couple of strokes on all the joint surfaces without risk of rounding the edges off and you can stay flat across the fingers too. I glue them on with Lee Valley's fish glue because it's water soluble and it allows me to peel the worn out paper off and replace it with new paper on the same laminate piece. I try to keep at least one of these sanding aids within arm's reach any time I'm doing anything in the shop.

CharleyL 04-02-2019 12:54 PM

You have done very well at this first, of likely very many boxes in your future. They are fun to make when you finally manage to get the tools to make them well. I make a lot of boxes now.

Here are a few tips for when making your next box, since I know you will, because they are so very addicting when they are easy to make.

For a small box you don't really need the slower drying rate glues. For larger boxes, it takes more time to get the glue on all of the needed places and then get the box together before the glue sets up. Excess glue on the outside isn't so important, because it sands off easily. The blue tape right close to the corner inside makes it easy to remove glue, but don't wait too long after the glue sets before you remove it. The next day the glue will be hardened on it and the tape will tear around it, requiring a chisel or knife to get it out. You can go with the White Elmer's glue for a slower drying rate too. It isn't quite as strong as yellow carpenters glue, but dries a bit slower, and it dries clear. The Titebond Extend is the better choice, but a box joint is very strong no matter what glue gets used in it.

Whenever I get excess glue on the inside of a joint I use a plastic soda straw to remove it while it's still wet, or at least soft. I push the end of the soda straw into the corner so it conforms to the joint angle and then just push it forward. The excess glue gets scrapped up, collecting inside the straw. I then either cut the straw shorter to do the next joint or throw the straw away, which I do anyway when the last joint has been cleaned. I have often been asked why I have a box of straws in my shop and this is the reason. It works to get most of the glue off of the blue tape too.

I have learned the hard way to make the fingers a bit long (about 1/16") and trim off the excess later after the glue has dried. I use a flush cut bit in my router table and a spacer to hold the box above the router table so the excess length of the uncut fingers don't touch the table. This keeps the box side being trimmed parallel with the bit and at a right angle to the table too.

I have a Join-Tech jig which works much like the Incra. When I started making box joints a lot it didn't take me long to decide that I needed a better way and bought the Incra I-Box jig. It was well worth the investment. With it and a Freud SBOX8 blade set I make box joints on my table saw with great results. This blade works better than a dado blade because it cuts a smoother square cut. The dado blades are OK for larger box joints, but aren't the best for small box joints. I also have a Freud 1/8" kerf square tooth ripping blade that I use with the I-Box jig when making very small box joints.

For making the bottom slots I now use Lee Valley small diameter box slotting router bits in my router table. I dry assemble the box sides and then just run the box sides around the router bit to cut the slot. Being a small diameter and with a bearing, these bits cut a perfect groove all the way into the corner. It's not visible from the outside of the box and you only need to slightly round the corners of the box bottom for it to fit and leave no gaps.

Box-Slotting Bits - Lee Valley Tools

Happy box making.


Flipsaw 04-02-2019 07:30 PM

What about using Hide Glue which has a longer working time ? Here is a site I came across with hardware:

Small Box Hardware - Brass & Nickel Plated Specialty Hardware

RickKr 04-02-2019 08:20 PM

Thanks, Charley. Good information.

As noted, I went with the Titebond 3. Since it was a small box, there were no problems with working time. Went very well. I have not yet, but need to order some TB Extend. I don't have any more boxes planned for the immediate future, so hopefully I order it in time.

Flipsaw. I did see some hide glue at the local store. Decided against trying it, as I felt comfortable with the TB3 for this box. Also, I found that small box hardware site and ordered some from them, and a couple others. It was hit or miss finding what I thought would work. Still waiting on all of it to really find out.

The blue tape worked great. I like the idea of the soda straws for picking up the glue. We have a supply for my granddaughter.

With this box, I discovered that I did not make the fingers long (deep) enough and have a few of the ends that are short of the surface. I should be able to sand them flat, as they aren't that far short.

I was not aware of the Join-Tech jig. It never showed up in the searches I was doing, but I was very focused on the Incra jigs. I almost bought the I-Box jig before discovering the LS Positioner. I opted for the LS so that I have the ability to do both. I'm very pleased with just the very limited use I've made of it. The precision aspect of the LS really suits me. We'll see if it really makes much difference as I use it down the road. I am anxious to try a dovetail, but only have a 1/2" bit now and no lumber I want to use. It means planing something to 1/2" thickness and that doesn't fit with what else is going on at the moment.

Those slotting bits look really great. I'll have to get a couple, once I figure out better what are my needs. I used the same slightly undersized 1/4" bit for the slots that I used for the joints.

Chuck. Your sanding aid trick sounds pretty slick. I recall my father taping a full sheet of carborundum paper to a granite surface plate when he needed to sand something really flat. I will have to wing it some other way, as I do not have any laminate, scrap or otherwise. I have a granite surface plate, but I'm not using it for this. I use the mesh-type sanding media (Mirka Autonet) on hook-n-loop sanding blocks and have a supply of the same in orbital sander discs. The blocks are not as flat and firm as laminate would be, but so far I'm satisfied with the results I'm getting.


DesertRatTom 04-02-2019 09:09 PM

2 Attachment(s)

Originally Posted by RickKr (Post 2009141)

I'd be interested in info about your invisible hinges. I've been searching various sites for small hinges and am not that satisfied with what I've found - for this particular box.


They are quite small, but disappear. You can get them in several sizes. I got some at Rockler.

RickKr 04-02-2019 09:56 PM


Originally Posted by DesertRatTom (Post 2010045)
They are quite small, but disappear. You can get them in several sizes. I got some at Rockler.

Very nifty looking. I will definitely use these on something in the future. The web site doesn't give their depths, but the technical data sheet does. The 10mm (0.394") are too large for the <1/4" Baltic birch plywood used in this box. The other larger ones are deeper than their diameters.

Thanks though, those will come in very handy,


RickKr 04-26-2019 11:45 PM

Finished Box
4 Attachment(s)
The first box, using box joints, is complete. It took a bit to find hardware that would work and I had to bend the strap hinges because I could not find hinges with holes that would fit the 6mm Baltic birch plywood. The bent strap hinges on the box started out straight like the double strap hinge on the table. Not having any sort of sheet metal break, I had to figure out how to bend them with a sharp, crisp bend line while keeping the strap flat and straight.

For the finish I used Liberon Beeswax with turpentine. I had never used it before, but I really like this stuff. It was fun to apply and I was amazed at the finish it gave. Smooth, slick and hard. I have not tested its water repellency, but it is not supposed to be used in high water areas such as kitchens and baths. I also got it for use on cast iron tables as it has no petroleum products.


CharleyL 04-27-2019 08:47 AM

It's tough to find hardware for thin boxes, but you did, and it looks great.
Congratulations on the successful build. Now with this one complete, I'm betting that there will be more boxes in your future.


RickKr 04-27-2019 11:51 AM

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Originally Posted by CharleyL (Post 2014515)
It's tough to find hardware for thin boxes, but you did, and it looks great.
Congratulations on the successful build. Now with this one complete, I'm betting that there will be more boxes in your future.


Thanks. You are right on both accounts.

There will be more boxes in the future. I was on the west side of Oregon a week ago and picked up straight and dovetail cutters that will allow me to make most of the box and dovetail patterns in the Incra LS Positioner master reference guide. Unfortunately, my time is required on some other matters before I can really begin to play.

I mentioned I had to bend the hinges to get them to fit. That "bending to fit" entailed bending the hinge at a location that allowed the screws to center in the narrow lid width, which also involved shifting the hinge pivot below the joint between the lit and box. Not what I wanted but I could not find any hinges that would fit and have the hinge pin at the joint line. I really wanted to find hinges with a strap long enough to have all the screws on top, but that was just not going to happen.

When the box is opened, the lid "swings back" a tiny bit. I notice it, but then the maker would. I doubt others would, but almost no one will see this because it is a storage box and just about only I will be opening it. It won't be sitting out anywhere for others to notice and/or admire.

I'll take this all under consideration when I make more boxes, to not make the lid so thin, but also out of something more interesting than plywood.


DesertRatTom 04-27-2019 12:14 PM

For a larger box like this, you could wrap the edges with some hardwood, maybe contrasting the lighter wood. The ply will look like regular wood and you'll have solid edges. But that is a very practical looking first effort that will surely help organize some tool sets. Nice save on that hinge bending solution.

CharleyL 04-27-2019 07:53 PM

I see nothing wrong with the way that you installed those hinges, but next time you may want to build the box complete with the top and bottom installed, then cut the lid free leaving a perimeter piece of the sides still attached to the top. This will stiffen the lid and also make it a bit easier to install the hinges.

When I do this, I always draw a light diagonal line down what will be the front side. A strip of blue tape would work too.
this is to help you keep the front of the box and the front of the lid oriented correctly when it comes time to attach the hinges and latch. It's almost impossible to make a perfectly square box, so keeping the top oriented correctly to the bottom will make both fit together perfectly even if the box is not perfectly square. You can easily see how far out of square your box it if you place the lid on the box 108 degrees out. If the box is perfectly square, it will perfectly fit, but I doubt you will see this happen. I try very hard to get mine perfectly square, but only very rarely can accomplish this.

Then I cut the lid free using my table saw with the blade set for the thickness of the box side. I cut opposite sides. Then I insert small shims and tape them in place to prevent the saw kerf from closing as I make the two final cuts on the two remaining sides. If you don't completely cut through all 4 sides, you can later use a razor knife to separate the lid at the saw kerf and then just sand the edges smooth.


RickKr 04-28-2019 10:57 PM

Thanks, Charley,

I've read about and seen videos on sawing off the lid that way. Looks like a really slick trick, which I will do, probably on the next box. I haven't figured out what that next box will be, but it may be while.

It is Spring and there is yard and garden stuff to do that can't wait. My daughter raises chickens (in my yard - about 30 of them) and told me today that she wants me to rototill the chicken pen. She has been spreading straw all winter, in part to add carbon to the ground but also to give the chickens some relief from the snow. It will be a nasty job. Chickens are one of the grossest animals I've ever been exposed to. But, should I want to grow a garden in that ground after she and the chickens move out, it will be a killer garden.

In the past, when she had incubated eggs in quantity, to raise new chickens to sell, she had set up brooding pens in my garage. Now that I have some woodworking tools to play with, I don't want to give up the floor space for the pens. She said the chicks can go outside in brooding boxes with mat heaters, so if that works, I'll be happy.


CharleyL 04-29-2019 09:19 AM

When you want to sand the edges of the cut that separates the top from the bottom, it's best to glue a couple of sheets of 100 or 150 sandpaper to a flat piece of plywood. Then attach this plywood to your workbench with a couple of screws to keep it from moving. Then place the box top or bottom on this sandpaper edge down and push it back and forth, making certain that you rotate the box and move the box in random directions. This will clean up the saw cuts and any mis-alignments of the saw cuts as well as make the edges of the box and top perfectly smooth. Be careful about sanding in many directions and applying even pressure, or the top and bottom may not fit together perfectly when you finish. If you try to clean up the edges any other way they are likely not to turn out perfectly flat.


RickKr 04-29-2019 11:50 AM

Yes, thanks. I had to deal with the unevenness of the joints at the top. The box joints didn't turn out perfectly aligned at the top. I tried cleaning them up on the router table, but that did leave slight differences that had to be sanded out. This box was small enough that it fit on a single sheet of sandpaper, but that will not always be the case.


twmv86 04-29-2019 12:37 PM

1 Attachment(s)
i just bought some hide glue for a project im doing. i used it years ago for long open times

CharleyL 04-30-2019 03:18 PM

Hyde glue of the hot melt kind is not as slow drying as the liquid hyde glue, so I'm glad you are planning on using the liquid version, but be aware that hyde glue in either form is not moisture resistant. The titebond II and III are. I think the Titebond Extend is like Titebond II. Your choice of glue should be dictated by the project you are building. Hyde glue is my choice when veneering or restoring old furniture though.


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