Monday, December 8, 2014

Sunday Toolfoolery - My Ever-Evolving Router Mortise Jig


Most of the time I enjoy fully immersing my head and hands in the work of furniture building.  But with when faced with a set of rote tasks, the "craftsmanship of certainty" becomes mighty appealing.  So when I choose to create joinery by machine, all style points are thrown out the window - I just want accuracy, ease of set-up, and repeatability.

Over the years I've created any number of second-rate router jigs that have haunted me through various projects.  Remembering where the tolerances were off, which way I had to compensate, and what moves had to be avoided, has become exhausting.  So I decided to build (what I hope to be) my last router mortise jig.



In some ways this is a response to the last one-off jig I made to mortise the through tenons for the Arts and Crafts Coffee Table.  This jig used a collar in a slot and encased the workpiece to ensure correct registration on every cut.  Besides the fact that it was purpose-built for one cut, it's top plate reduced the router's effective depth of cut and you couldn't flip the workpiece end-to-end to come at the mortise from each side.  This meant that you had to rotate the piece 180 degrees and register off the other side to cut a complete through mortise.  No matter how accurate the jig, you still needed to sand the inside of each wall to get a truly square mortise.  Way too much work.

The new design (cadged from a Fine Woodworking article, some other blogs, and my own experience) looks to address these shortcomings.  It really comes down to two things:  How do you hold all sizes of workpieces stock still in the jig, and how do you move the router across the workpiece in a smooth fashion with no slack.  The body of the jig is about eight inches tall by about two feet by about 3 inches wide.  The exact dimensions are not important, but make sure you can attach it to your bench via the dogs in a vice and a hold-down.



Holding the Workpiece:
The system begins by routing vertical grooves to hold two pieces of t-slot in the jig's body.   This houses 1/4"-20 T-slot bolts that attach to a shelf to hold the piece to be routed.  The shelf is three pieces of  face glued 3/4" plywood.  The T-slots allow you to place the workpiece on the ledge and move it to a position level with the top of the jig.  I secure the bolts with star knobs.



The ledge takes most of the downward force from the router, but you still need to hold the workpiece against the vertical face of the jig.  I rout a slot across the ledge and install another piece of T-slot track.  Incra makes some nice hold-downs that you can install in the slot, but I made mine from pieces 1/8" by 3/4" steel available at a big box store.  I cut a 6" length, drill a 1/4" hole and bend a 30 degree crook on the end.  I have found that the pressure from a star knob hold everything in place.

Installing the Router
This was the trickier bit.  I knew that I wanted to use the adjustable fence on my Dewalt 621 to guide the router across the jig.  At one level this works well on its own, but I wanted to add a degree of accuracy that didn't depend on constantly applying pressure against the jig.  Experience has shown me that, particularly when plunging the beginning and end of a mortise, the router can shimmy and widen the slot by some fraction.  This is fine for loose tenon joinery, but less so when creating visible through tenons.



I'll spare you the prototypes that failed, but I finally settled on a piece of sliding T-slot track, routed in place so that the fence of the router guide (with the plastic doodads removed) lined up with the sliding portion of the track.  I roughed up both bits and epoxied them together in situ.  Once cured,  I drilled holes and inserted bolts for more stability.


The last step was to install stops to define the travel of the router.  This is achieved by installing (more!) T-slot track and using wooden blocks that can be moved and set via T-slot bolts and star knobs.

I've been quite happy with the jig in the short time that I've used it, and the fact that my Festool dust extractor is reverse engineered to match the port on the Dewalt, is a real plus.  Please feel free to send me a message if some of these ramblings are confusing!










Tuesday, November 18, 2014

Collaborating on an Arts and Crafts Coffee Table - Building the Base


One of the enjoyable things about building in the arts and crafts style is that you are offered a wide variety of joinery options.  As I was working with a friend who was newish to furniture building and who was interested in construction techniques, I thought we'd go through the paces with both full on machine, machine-assisted, and hand-cut joints.

The Back and Side Aprons
When I bought the Domino I was afraid that I would lean on it a bit too much when I designed a piece, but this is the only place where I broke it out,  Very straightforward using the largest size bit.

The Bottom Stretchers
Wedged through tenons give the table a solid look and feel.  I used my newly improved mortise router jig to do the bulk of the removal and squared it with a chisel.  We rough-cut the tenons on the table saw and my friend Andy used a router plane to dial in the fit.  We will wedge the tenons after the initial steps of the finish are applied.

The slight gap at the top and bottom will be closed when we drive home the wedges


The Front Apron/Stretcher
Old school dovetail joint is hand cut assures that the table stays square.  It is narrower than the back apron to provide easy access to the shelf.  We also decided to eliminate the drawers in order to maximize this space.

Double sided tape hold the tail in place to mark the mortise


The Lattice Shelf
Flat-sawn white oak is cut into 1 1/2 strips and then turned ninety degrees to expose the ray pattern.  Once one is marked we gang them up on the tablesaw (equipped with a dado blade) and cut the lot.  These will trimmed to size and chamfered during our next work day.

Everything is left oversized until we look at the final proportions


All that remains are a few final steps and to begin the multi-step finishing process.

Sunday, November 9, 2014

Collaborating on an Arts and Crafts Coffee Table - Gluing Up the Top with Breadbord Ends



Arranging and finishing a quarter-sawn white oak top offers a set of unique challenges.  Unless you have a large inventory of stock to draw from, you will likely be flipping and switching the boards around in a way to take advantage of the signature ray fleck pattern.  Once it works for you visually, chances are that the grain will be running in both directions along the top.   This table was no exception.

What this means, of course, is that you won't be pulling out a plane to level the individual boards or create a final finish -- it will be scraped and sanded into submission.  This is not too onerous if you take special care during the glue up.



The objective is to have the boards so straight and square that they practically guarantee a positive result.  Dimensioning the stock over several days helps tame the natural wood movement and a full scale dry-run predicts the outcome.  I happen to prefer pipe clamps, but Rob Porcaro over at Heartwood makes a compelling case for Jet bar clamps. 

I spring the joints on this 2'x4' glue up and use only enough pressure to get a uniform bit of squeeze out from the two middle clamps.  If I am wrestling and wrenching it, something has gone wrong in the preparation and this should have shown itself during the rehearsal.  The outer clamps need very little pressure.  If all goes well the greatest variation across the top will be less than 1mm.
After drying overnight, it took less than an hour to scrape and sand the top flat to 180 grit.  Still over sized, it was time to create and install the breadboard ends.


This top is +/- 1" thick so the tongue and groove will be cut at 3/8".  This is driven as much by my tooling (I have a 3/8" spiral router bit and a 3/8" pig sticker mortise chisel) as by convention.  I cut the blind groove first, dropping it down on the router bit in a series of passes (I hate this move) until I get the desired 5/8" depth.  After marking, I mortise the breadboard "tails" by hand.



I used my usual approach to using a router to cut the breadboard tenons and cut them to within 1/16" by machine.  A series of handsaws cut the profiles and rabbet and shoulder planes fine tune the thickness of the tail.

The extended length or "horns" on the end help while you are test fitting, and my goal is to have it just snug enough to slide into place with a few well-placed blows with the side of my fist.



The last step is to plane the final thickness of the ends.  This is a judgement call, but I like to have them just proud of the top, ensuring that all end grain is covered, but not so high as they might get caught and chipped during normal use.  I slide the end out about 1/2" and protect the top with masking tape.  From this point it is just a matter of test fitting until you are happy.



I secure it in my normal way (coincidentally, Jeff Branch just did a SketchUp version of breadboard ends which is a nice demonstration of this process) and take a look at how the proportions are working out.



Next up, we work on the legs and base construction.

Sunday, November 2, 2014

Collaborating on an Arts and Crafts Coffee Table - Concept and Design


Drawing from a number of sources, I built this model to get us started.
I have a friend who has some woodworking experience and is interested in building his first serious piece of furniture.  Given that what we do is a pretty solitary business, I jumped at the chance to help him design and build a mission-style coffee table for his home. Working side-by-side, over the course of several days, the plan is to complete the piece and build a few skills along the way.

I've put a decent amount of thought into this, and it seems that I need to keep three questions in mind - questions that may be slightly different than I work alone:

How do I make the experience interesting?
Every project has its share of mind-numbing repetitive tasks.  I'm cool with that, but is he ready for the fatigue that sets in during the twelfth half-lap joint or during the long process of trimming a tenon with a router plane?  In conversation I tend to fill the empty space with blather, if I do that over the course of ten hours I'll be exhausted.  Plus, how do I avoid pushing a bunch of useless busy work off on him?

I suspect that the answer to all of these questions is to think through every step, anticipate most hang-ups, and create a task-by-task work plan that encompasses the entire project from start to finish.  This is not my usual approach - even when we went to get the stock I was just working off the model with a vague sense of what we need (about twelve board feet of 5/4 quartersawn white oak, enough 8/4 flatsawn white oak to make the legs, and something like one twelve ft long, eight inch wide board of 5/4 flatsawn oak.)  Teaching, even in this very informal way, takes much more organization than doing.

I hope this list of tasks will make good use of our time.
How do I ensure that the piece lives up to our shared expectations?
When we discussed the table, I Googled  "arts and crafts coffee table image" and asked him to pick his favorites.  A search like this runs the gamut from classic pieces to awkward knock-offs.  He picked a couple photos and I drilled a little deeper with open questions like "What do you like about these tables?" and more focused requests such as "So you really want drawers and a shelf below?"  The image that he really liked was a bit awkward and I told him I'd give it some thought.

This is where it gets tricky.

My part of the "shared expectation" is that I want to build furniture that has good lines as well as sound, attractive construction.  I figured that I should spend a few hours building a model that met his technical requests and improved upon the design he selected.  I was pleased that once he took a look at the altered design (replacing the heavy board on the bottom with lattice-work and adding breadboard ends with walnut handles and accents) he liked it better than his first choice.  Sometimes I have to be reminded that customers are generally pretty open-minded and they trust you to bring your own ideas into play

How do I keep us both safe?
Banging on about safety is boring and condescending - but it has to be thought about.  If you work in a shop your level of caution automatically adjusts to the potential danger (turned up to 11 around the table saw, slightly less at the jointer, even less at the drill press.)  But if this unfamiliar ground, you have no idea about the many ways you can injure yourself in the shop.  I think we will start with an adult conversation about what he feels comfortable doing, a rundown on the dangers associated with each tool, and how I will supervise until we are both comfortable.  Most important, we will have an absolute rule that he will stop if it doesn't feel right. 

I think he will work with hand tools for the most part.  They come with their own set of risks but they are usually more rewarding.  And since there will be some machines involved, this gives me an opportunity to take a hard look at my jigs and templates to make sure that they are both safe and sturdy.

This will be a fun project and a chance to share time with a good friend who is enthusiastic about woodworking.  I'll post an update in a couple of weeks, and later this week I'll begin a contemporary ash bench with sculpted edges.

Sunday, October 26, 2014

Building a Lutyens Garden Bench -- Assembly and Completion




This bench has sat around the shop, half-completed, for more than a year now.  I guess there is something to be said about deadlines driving results and how you can lose inspiration in the middle of a long job.  I also think the fact that it is a project built from purchased plans takes away some of the joy.  I mean, you just read the instructions and you are home free, right?

Not quite.

The art nouveau lines, as elegant as they are, often point to less-than-elegant construction techniques. All those curvy bits have to be joined together and there is no way around some less-than-stable short grain appendages.  That being said, the designer did the best he could with what ends up being a very nice piece.

I departed from Taunton's plans in a couple of ways:

First, once I had the skeleton of the structure built I ignored the plans and worked off story sticks and my own actual measurements.  This is sort of a given on all custom furniture, but it is easy to forget when you get in paint by number mode.  Plus, nearly every set of plans I've worked with have at least one error and this was no exception.  To their credit, I seem to remember Taunton sending out an email correcting the errors in the plan.



Second, I replaced some of the tedious double dowelled tenons on the intricate back with more integrated domino joints.  It feels more secure and it has little effect on the glue-up choreography.  As with all domino/plate joiner work the most important thing to keep in mind is not "Is this perfectly centered?, but "Am I referencing the same faces when I use the tool.  I referenced the bottom (using the bottom plate on the mft table to cut the rails; placing a stop to match the bottom of that rail on the stile.) and the front of the piece using one of the stops on the domino face.  With a little concentration it went quickly.


The glue-up is complicated and you may want a patient assistant to ease the pain.  I used slow-setting epoxy for most of the large joints and dominoes but Titebond III for the dowels.  It was just easier to squirt glue into the round holes than coax the gooey epoxy into such a small space.  What can you say about a fancy glue-up?  As long as your marriage survives, and you arrive at the end with an assembled piece of furniture, it is best forgotten.

I used stainless steel screws, countersunk and topped by oak dowels to secure the seat slats and it will get several coats of Epiphanes Marine Varnish before it goes out in the Spring.  I hope to knock back the gloss finish with some steel wool to get a less plastic looking finish.


Sunday, October 19, 2014

Sunday ToolFoolery- My Festool Domino Work Triangle


I've never been one to engage in the bloodsport that is the handtool-vs-powertool debate.  We each come to the craft from a different perspective, with varying objectives, and with specific limitations on our time and budget.  I have as much respect for the woodworking Samurai who shapes each mortise with a chisel,  as the one who creates the flowing lines of a rocking chair with a keen eye and a bandsaw.

So it was only a matter of time before I embraced the Festool Domino (btw, I get nothing from Festool; I pay their cosmically stated rate on every purchase.)

And while I have no intention of of adding to the long list of breathless reviews for the tool, I have found that it works quite well in my shop where hand and power tools work side by side.  I call it my Domino Work Triangle and I think that it is a good system for repetitive tasks such as attaching aprons on small tables, inserting slats in arts and crafts pieces, and constructing rails and stiles in frame and panel construction.  You may already take a similar approach for slip-tenon joinery.

1.  A Mitre Saw on the Bench
One of the happiest days of my woodworking life was when I exiled the chopsaw from the studio and sent it to the garage.  Rough stock is cut to length with an old Disston, surfaced, and then cut to final length on my renovated Stanley mitre box.  It rides in the tool tray, has an adjustable stop, and generates a tiny amount of dust.  When stock is marked with a knife you can get very accurate, square cuts.


2. A Mitre Plane in a Shoot Board
A truly perfect joint requires that each edge be square and true.  As the Domino creates the perfect internal bits of a mortise-and-tenon joint, you are left to focus on creating a perfect fit between the shoulder and its mating piece.  Never has a tool that feels like such an indulgence proved to be so necessary.  It is astounding.  Because it weighs in at something like eight pounds, it glides through 2"x3" white oak end grain with ease.  The shoot board attaches to the other end of my handtool bench and doesn't interfere with the mitre box.  A few swipes takes me to the knife line.


3. A Domino on a Festool Work Table
In for a penny, in for a pound.  With a couple of commissions looming and several ideas for spec pieces in my head, I just didn't feel like building anything else for the shop.  I laid out the money for the mft system and I have no regrets.  This third leg of the triangle sits to the right of my bench and is light, strong, and provides another dead flat worktop for the Domino.  I know Fine Woodworking just did an article about jigs for the Domino, but I just clamp the work to the top and let it rip.  Instead of referencing off the top plate, I often use the bottom of the tool riding on the worktop.  On small pieces this provides more stability.


It goes without saying that this combination of kit comes at a price.  It does save me a great deal of time and allows me to spend most of my mental energy on design and details -- and design and details are reasons why someone commissions a piece of custom furniture.  But even if you are just building for yourself, there is something elegant about working with tools that do their jobs well and make your time in the shop successful and rewarding.

Sunday, October 12, 2014

Sunday Toolfoolery- Installing Threaded Brass Inserts By Hand



Some time ago I posted a video demonstrating how to use a drill press to install brass inserts into wood.  While you don't actually fire up the machine, you do take advantage of the steady, perfectly aligned down pressure provided by the tool.  That system works well with pieces that can be easily brought to the machine, but larger slabs require you to install them by hand.  And without the precision and heft of the drill press it is easy to get less than satisfactory results.

I also noticed, as I was ordering new hardware, that there are lots of general questions about these particular inserts.  I don't claim to be a world-class expert on these things, but I have come up with a couple of tricks that take the stress out of installing brass inserts by hand.

1.  Question Authority
The only instructions that come with inserts is a recommended diameter for the pre-drilled hole.  I don't know if it is result of sloppy manufacturing, or if there is some industrial process by which these get installed in a factory setting, but in my experience this number is often wrong.  I drill a couple of test holes in similar material with gradually increasing diameters.  I start with the recommended number and then another 1/32" larger and then another 1/16" larger.  Test the fit in each (the first will be very tight) and drill the appropriate hole in the actual project. 

This insert was installed using the recommended 3/8" diameter hole.  Even with the jig, it distorts the wood and looks botched.
For me, the right size is the hole that provides clearance for the body of the insert and enough purchase for the threads.  Oh, and do your self a favor and skip the screwdriver . .


I increased the diameter by a full 1/16".  The threads have plenty of grip and the insert does not distort the wood.

2.  Spend a Few Bucks on the Right Tool
For five dollars you can buy a purpose-built T-handle that screws into the insert and lets you bypass the chipped tops.  Again, this is just my experience, but the flat head screw grooves are better for removal - less so for insertion.  Armed with the new toy, a registration block (with a hole the diameter of the T-handle, drilled at 90 degrees to the workpiece) guides the insert.  I have a couple of holes drilled to deal with any tight spaces and I affixed sandpaper to the bottom to keep it still in use.



This seems like a lot of words on a simple task (akin to instructions on a bar of soap) but hopefully it will help you avoid unsightly mishaps on one of the last steps of a project.