When installing solid brass hardware in fine woodwork, matching solid brass screws are essential to complete the look. However, brass wood screws are weak compared to their steel counterparts and there often is limited depth with which to work, such as in a small box lid.

Lee Valley recommends the use of brass machine screws as having much better strength than brass wood screws in short holes. I have tried this with excellent results with 4-40 (above, left) and 6-32 (above, right) flat head brass machine screws. Here are the details.

The why

The machine screw has the advantage of a thicker, non-tapered body that is less likely to break than the wood screw as you torque it down. Furthermore, because the machine screw threads have already been cut by a tap, the screw goes in easily and only tightens as the head meets the countersunk hole in the hardware.

By contrast, a brass wood screw has to cut its own threads and the screw is stressed throughout the range of installation. Yes, you can use a steel screw to pre-cut the threads, but good luck trying to find a steel wood screw with threads that match the pitch of the same nominal size brass wood screw. They usually do not, which means you are simply breaking down some of the inter-thread wood that the brass screw’s holding power depends upon. A recent Brusso hinge set came with such a mismatched steel screw.

Tightening into a properly tapped hole, the brass machine screws feel very solid. I find I can now relax with this method for small hardware installation.

The how

The preparatory hole is drilled at the root or “minor” diameter of the machine screw (the diameter of the screw body without the threads), which yields 100% thread depth when the hole is tapped. Typical work in metal uses 75%, or less, thread depth by using a pilot hole somewhat greater than the root diameter of the screw.

For 4-40 machine screws, the minor diameter is .0813″. This is approximated with these drill bits: 2mm (.0787″), #46 (.0810″), and 5/64″ (.0781″). For 6-32, the minor diameter of .0997″ is approximated with these bits: 2.5mm (.0984″), #39 (.0995″), and maybe 3/32″ (.0938″).

Fortunately, those wonderful folks at Lee Valley sell inexpensive sets of drills in the metric sizes with imperial taps through 1/4-20. In cherry, maple, and shedua (ovangkol), all tight-grained hardwoods, the method worked very well in 4-40 and 6-32. Of course, it pays to experiment beforehand in the specific wood species.

Use a standard-point tap and ratcheting hand tap wrench for most situations, but consider a bottoming tap when you want to eke out every last bit of functional depth. Tap carefully, without wobbling the tool, especially for the smallest sizes whose wood threads are still fairly delicate while in the formation process. Even fine threads in wood are surprisingly sturdy once they are fully filled with the screw, but I like to harden the wood threads with a tiny bit of cyanoacrylate glue. Epoxy is not worth the hassle in my opinion.

I bought a supply of brass machine screws 4-40and 6-32 in longer lengths than required and easily cut them to length with an electrical multitool (shown), and then filed the cut edge clean.

Since we are often dealing with shallow depths and small tolerances, make sure the screw will actually tighten against the countersunk hole in the hardware and not just tighten against the taper left by the tap at the deep end of the hole.

I often prefer to enlarge the countersink and hole in brass hardware if there is room to accommodate the next larger screw size, e.g. 4-40 to 6-32, for more strength.

I was listening to a Pandora station in the shop today and it got me to thinking.

Pandora is a wonderful music app that characterizes each song or track of recorded music using “hundreds of musical details . . . melody, harmony, instrumentation, rhythm, vocals, lyrics . . . and more” based on the analyses of Pandora’s team of expert musicians.

With this information, Pandora plays songs that it figures you will like based on “stations” that you set up. The play lists of your stations get refined as you tell Pandora more of your preferences via your continuing “like” and “don’t like” inputs, which the app remembers.

Among my stations (Motown, SRV, etc.), one of my favorites during exacting hand tool work is solo classical guitar music. I’ve guided that station to play lots of J. S. Bach’s unaccompanied violin, cello, and lute music transcribed for guitar. Having just given a thumbs-up to a few tracks of Bach, Pandora then presented some similar sounding tracks, which made perfect sense based on the music’s objectified elements.

But I thought the tracks, analyzed to be similar to Bach, were pretty crappy. Yet Pandora’s system is very sophisticated and this is no knock on Pandora; I highly recommend it.

Thinking theoretically, if you took every detail of Bach’s music, every element, every nuance, everything, well, then I suppose you would have Bach – and nothing else. But wait; Bach already did that, as only he could. That’s why his name is on the music.

OK, you’ve stayed with me this far but “Rob,” you say, “what the heck does this have to do with woodworking?”

The things you make are not defined by how well you fit dovetails, or how nice your well-tuned planes produce surfaces, or even the woods you choose. Your pieces are not fully definable by style, even your style. Each piece you make is ultimately definable only by itself – all of it, and all of it together, as it exists. Just like the music, there are limits to how much you can characterize or analyze it before you essentially reconstruct it.

That’s the word: construct. You do that when you design and build something. Just like the music tracks, it has innumerable characteristics but cannot be truly described except by the whole of it – what you built.

How grateful we should be, to make something – and sign it.

Good lighting is one of the most under-appreciated assets for fine woodworking, especially handwork at the bench. It is a shame to see an elaborately equipped shop with nothing more than fluorescent ceiling lights illuminating the workbench.

Basically, the properties of lighting are intensity, distance from source to the object, angle of incidence, and quality, which includes the color cast (color temperature). Without delving into technical detail, for detailed tasks such as hand cutting joinery, you want a strong light that is adjustable for distance and angle, and has a pleasing whiteness.

The Super Nova lamp from Woodturners Wonders delivers big time on all counts. It was developed by woodturner and inventive guy Ken Rizza for use with a lathe but is just as useful for general woodworking. The three LEDs in the lamp head together use 9 watts of power to generate 870 lumens.

This is a heavy-duty lamp. The 30″ flexible stainless steel neck, covered with a black flexible, non-reflective shroud, holds its adjustment in any position. This is the key to the effectiveness of a lamp like this – the light can be adjusted to the exact location and direction desired and it stays put. The heavy rectangular base houses a switchable magnet that holds with 286 pounds of force! The base is large enough to easily accommodate a clamp to secure it to a wooden surface.

Below is not trick photography. The base is holding unyieldingly to the even the 2mm sheet steel of the bandsaw cover, while the neck does not sag a bit when fully extended. Wow!

The LEDs are rated for 50,000 hours life (8 hours/day every day for more than 17 years). The lamp is equipped with a generous 9-foot cord. Unfortunately it ends with the obligatory transformer but at least this one is small and light. A minor complaint is that I wish the switch button was placed on the back of the lamp head instead of on the side of it because I tend to switch the lamp off when grabbing the head to adjust it.

This bad boy lamp is not cheap at a regular price of $159 (look for sales) but a good light is one of the most important tools in the shop. It is by far the best lamp for detailed bench work that I have ever used or seen. Several cheaper “good” task lamps have frustrated me over the years. I cannot at this time attest to its durability but it certainly seems sturdy and does carry a two-year warranty. Smaller models are available.

I suggest trying a top quality task light in your shop. You may be surprised what you have been missing as you experience the improved visual feedback for detailed handwork, and using a raking light for surfacing and finishing.

This review is unsolicited and uncompensated. I have no affiliation with Woodturners Wonders.

These Sensgard Zem hearing protectors are the best I have ever used. Before elaborating, I will explain the problems I have had with some other protectors.

I do not like stuffing things into my ear canals. This includes foam plugs that are first compressed with the fingers, which are often dirty, then jammed in where they are uncomfortable and then tend to work their way loose. Various silicon, latex, or high tech torpedoes that are also held in the ear canal much as a cork is held in a wine bottle are also unwelcome in my ears.

Bulky, cumbersome earmuffs are at the other end of the range of options. I have top-quality Peltor muffs but even with their soft padding, they squeeze the temples of my eyeglasses uncomfortably against my skull. It isn’t long before I decide the noise is more tolerable than the headache.

Finally, all problems are solved with Zem hearing protectors by Sensgard. The replaceable foam cuffs of these extremely lightweight protectors comfortably skirt the entrance to the ear canal. The acoustic chambers (the arms) vault my eyeglass temples – no more skull aches. They go on and off in a snap, and when not in use, hang around the neck or fold compactly for storage.

All these advantages would be enough but here is the best part: the noise reduction is phenomenal. I powered up my DW735 thickness planer, measured 100 dB(A) at 2 feet under no load, and then put on the Sensgards. I was flabbergasted at the dramatic but even, pleasant noise diminishment. The nominal NRR (Noise Reduction Rating) is 31 but they are far more superior to my Peltor model, listed at 28, than the numbers might suggest.

I actually had to accustom myself to remaining alert to the ferocity of woodshop machinery while enjoying the auditory peace. Yet, I could adequately hear important shop sounds such as speech.

More information about the Zem technology is available on the Sensgard website. I have the NRR31 model in easy-to-find lime green. Put them on according to the simple package instructions; that makes a big difference. I found the lowest price on Amazon. Extra foam cuffs are good to have.

[This review is unsolicited and uncompensated. I have no connection with Sensgard.]

When to remove the clamps

The instructions on the Titebond III bottle recommend “clamp for a minimum of 30 minutes (longer is better)” and “Do not stress joints for 24 hours,” which is how long PVA glues generally take to fully cure.

I leave the clamps on at least overnight. There really is no hurry to remove them unless they are needed for other work. Furthermore, I will not be working the board for at least 24 hours to allow time for the joint to condition and the board to reach a uniform moisture content as excess moisture exits the glue line area. This avoids producing a sunken joint line or depressions over the biscuits when surfacing the panel.

Also, it seems plausible that the joint could be stressed from changes in moisture and applied forces if the clamps are removed too early in the curing process.

For these reasons, I put the assembly aside and wait until the next day to remove the clamps, tending toward longer times for larger work, and up to 24 hours if there are any doubts about the behavior of the wood. Small, light panels such as a drawer bottom can be unclamped sooner.

Flattening the panel

Hopefully, this will be fairly easy and corrections will be well within the range of hand planing for small to medium panels if biscuits were used for alignment. The panel only needs to be flat enough for its function. Don’t worry about small imperfections that yield to light hand pressure and, for example, a table frame will easily flatten. On the other hand, don’t allow an errant panel to twist the frame of a light cabinet door that needs to fit and close precisely.

As needed, work diagonally with the jack plane to true the surface, then finish off with the smoother or scrape or sand to the final surface.

If you glued up a large panel in stages, you may be able to flatten the intermediate glue ups with a wide jointer-planer, minimizing the work required on the final panel. For a big table top that needs significant correction, consider using the services of a local commercial shop with a giant wide-belt sander.

It is reassuring to do some testing on the off-cuts, as in the photo at top. I grasp both ends of the off-cut and bash the joint line against a hard table edge. Though the force is directed on or very close to the joint line, only the surrounding wood will break while the joint line remains intact.

Summary

To confidently and efficiently produce sound edge-to-edge joints and beautiful glued-up panels, here is what to do:

1. Select reliable wood to produce visual and structural harmony, especially along the joint line.
2. Use straightforward methods, finishing with hand planes, to make good joint surfaces that fully meet. Use the slightest bit of camber as a one-sided tolerance.
3. Use biscuits for alignment in boards thick enough to accommodate them and the special method for small, thin boards.
4. Use parallel-head clamps with a simple tunable setup.
5. Rehearse the glue up then work fast.
6. Feel good about what you made – it’s going to last!

Closing thoughts

I hope this series on edge-to-edge joints will assist you in this essential aspect of woodworking. In writing this blog, I want to empower people to make things and experience the quiet – yet great – joy of it. I’m not an infallible guru – no one is. Nevertheless, I can assure you that these methods are carefully thought out, researched, have been used by me for many years, and actually work in my shop.

Of course, there is more than one good way to do almost everything in woodworking, so you will surely find those who disagree with some of what I have presented. No problem. Please do consider alternatives, try things in your shop, and ultimately use your judgment to find what works for you in your shop to give you the results you want.

NOTE: The entire 6000-word series on Edge-to-edge Joints and the many other series on this blog can be conveniently accessed via the Series page.

This discussion primarily applies to PVA glue, which most woodworkers use for these joints. I prefer Titebond III for its relatively long open time, ease of use, and dependability. Alternative glues with longer open times include special slow-set PVAs or liquid hide glue.

The gluing process

Speed is paramount. It is absolutely imperative that the thin layer of glue not start to skin over or stiffen. This can result in a weakened joint and/or a glue line that is too thick. I suspect this is one of the main causes of failed edge joints and cosmetically poor joints.

A good glue up requires a rehearsal – it is worth the time. Dry clamp the boards, working out clamp placement and distribution, and examine the joint. When readying for the glue up, prepare the clamps open to the correct length. Rehearse how you will hold and move the boards for glue application. For example, the middle of a three-board panel needs glue on both edges. How will you support it for gluing the second edge?

Again, if the glue skins over at all, you lose, so when it’s game on, move fast! In the first photo below, the glue is good to go but the glue that is partially skinned over and stiffened in the next photo will produce a failed joint.

Applying glue to both sides of the joint ensures good wetting and equal penetration on both sides of the joint. Set up two edges side-by-side and work on both at once. First, put a modest amount of glue in the biscuit slots where its bulk will delay skinning over. To apply glue to the joint surfaces, I run a bead directly from the bottle and then spread it out to the edges with a brush or roller. Using my finger to spread the glue seems inevitably to transfer glue to somewhere I don’t want it.

I like the inexpensive hog-bristle brush available from Tools for Working Wood but I crop the 1 1/2″ bristles to about 7/8″ (see photo at top), which allows me to push the glue faster using it nearly upright. Flux brushes are a poor substitute as they cannot spread the glue as fast and shed bristles on the work.

Squeeze out

I aim for light squeeze out along the full length of the joint, trying to avoid dripping. In theory, one could apply the perfect amount of glue that is just short of producing any squeeze out but then when you assemble the joint and see no squeeze out, you would not be sure if there is just the right amount of glue inside the joint or too little. Thus, squeeze out is simply assurance that you have applied enough glue and as such, there is no point in making it excessive.

As for removing glue squeeze out, I prefer to wait until it is rubbery then lift most of it away with a sliver of wood cut to a chisel edge. Then I spot remove most of any remaining glue with a wet rag that is more than damp but less than drippy.

I recall reading somewhere that removing the squeeze out before it fully dries can cause the outside of the glue line to dry faster than the interior and thus produce a tiny gap on the outside. There may be some truth to this as I have infrequently observed a hint of gapping early on after clearing the squeeze out but it has never persisted in a well-made joint. Therefore, and also because removing substantial fully dried squeeze is a hassle and can chip the wood, I keep it practical and don’t worry about this issue.

Next: Finishing up, a summary, and a thought.

Clamping capacity

Can small shop clamping methods generate enough pressure to make a good edge-to-edge joint? The short answer is yes. Let’s look at the details.

The US Forest Products Laboratory in their very useful Wood Handbook, chapter 10, page 16 (2010 edition), recommends pressures of 100 pounds per square inch for low-density wood and up to 247 psi for the highest density woods. The book also states: “Small areas of flat, well-planed surfaces can be bonded satisfactorily at lower pressures.”

Jet claims (I suspect rather conservatively) 1000 pounds of force can be generated by their parallel-head clamps while Bessey claims 1500 lbs. for their similar K Body Revo clamps. As an example, 1500 pounds of force produces 200 psi over a 10″ length of 3/4″-wide glue line (7.5 square inches area).

So yes, adequate pressures can be generated in the small woodshop. There’s no need to get out the calculator, just lean toward more clamps and more torque with denser species/thicker boards and less beef with less dense species/thinner boards. And, of course, make good joints.

Clamp spacing

How about spacing the clamps? This depends partly on the above issue but also on the mechanics of the force spread. Even a wanabe engineer like me can surmise that the board is acting as its own caul and thus the transmission of force to the glue line depends on the width and stiffness of the board. I long ago adopted, with consistent practical success, Ian Kirby’s rule that the clamp force can be assumed to spread in a 45° fan.

Thus, referring to the diagrammatic photos herein, the maximum distance between clamps (remember, there will be clamps above and below the panel) should be twice the width of the narrower of the two outer boards in the panel. Shown at top, the 5″-wide board requires fewer clamps (maximum 10″ apart), than the 2 1/2″-wide board below (maximum 5″ apart), if all else is equal.

Assembly

Regarding assembly, I first moderately tighten the center clamp, and then work outward, avoiding heavy pressure. Then I add the upper gang of clamps, moderately tighten them, check with a straightedge for problems, and make any needed adjustments. Then I torque down everything, and check/adjust again. All of this is done very quickly!

Accordingly, I glue up any panel with more than three boards in separate sections, and usually prefer to limit the sections to only two boards, especially if the intermediate panel can fit in my jointer-planer. This is wood – nothing is perfect all the time. I’m usually working with very expensive stock and like to preserve the opportunity to reset any errors rather than let them accumulate.

Next: Glue issues.

Clamp setups

The most important step in a trouble-free clamping regimen for edge joints is to get a set of parallel-head clamps, such as those made by Jet and by Bessey. These invaluable tools eliminate most problems.

It is best to do the glue up on a flat base such as a workbench with a sheet of 3/4″ MDF on top or a dedicated assembly table. You then want to transfer that flatness to the panel to be glued.

The best and most versatile method, especially useful for gluing up long boards, is to rip two thick boards to the same width and set them on the work surface parallel to the clamp bars where they will act as bearing strips. The top photo shows the bearing strips with the lower gang of clamps. One panel board is mocked up in place.

Make the height of the bearing strips sufficient for the boards to slightly clear the clamp bars, and cover their top surfaces with packing tape because glue will squeeze out on to them. You can make corrections for imperfections in the work surface by simply shimming the bearing strips.

[Tip: To make adjustments for creating a flat, untwisted bed for the panel, think of the bearing strips as winding sticks. View them directly as such or place actual winding sticks on top of them. Shim as needed.]

If the work surface is flat and the clamps uniformly sized, a quick method would be to put the boards directly on the clamp bars. However, glue will squeeze on to the bars, which is messy even if they are covered with plastic, an additional nuisance. Alternatively, pieces of 1/2″ MDF can be placed across the clamp bars and away from the glue lines, as shown below. This works well for small scale work and will keep glue off the bars unless it drips.

These setups keep the boards close to the underlying clamp bars and thus minimize forces that would tend to bow the bars. A possible problem with the second method, where there is no air space between the underlying clamp bars and the work pieces, is the transference of bow in the tensioned clamp bars to the glued up panel, though in practice and testing, I have not found significant bowing using heavy clamp pressure.

I almost always alternate clamps above and below the panel because this seems more reliable and safer, especially when later moving the assembly around the shop. Further, it affords an opportunity to tweak the pressure balance if things are amiss. After experimenting with light panels, observing for distortion, I think one could get away there without alternating, but I have found no practical disadvantage to alternating in any case.

The bars of the fewer upper gang of clamps will be further from the panel boards, so in theory, this produces asymmetric bowing forces. In practice, this is little or no problem but if there is any upward bowing of the panel, you can slant the clamp heads or use the short sides of the heads to bring the bar closer to the work piece.

Again, I have never found the need to use over-under cauls or those specialized clamps that produce a similar effect.

One more thing: Parallel-head clamps also obviate the need for the pyramidal pressure blocks described by David Charlesworth in the article “Accident Prevention” in Volume 2 of his excellent Furniture Making Techniques series. The blocks (or similarly, rounding over the outer edges of the panel) make good sense to neutralize the effects of the bowing that seems to occur with the sash clamps he is using.

Next: clamp pressure and how many clamps do you need?