Friday, October 13, 2017

MFA Kabukimon Redux

It has been a couple of years now since the kabukimon for the Tenshin garden at the Museum of Fine arts in Boston was completed.

Here's a reminder of how the original gate looked, after 25 year's service:

The old gate's wooden elements sat right down at ground level, and the main posts were supported by large steel plates front and rear. The wood under those plates - indeed, all of the wood at ground level, was considerably rotted, as one would expect. The door frame parts were completely rotten as well, as was the main cross beam, or kabuki, as it had a stress relief kerf running along the upper surface open to the weather. At some point there had been a piece of copper flashing face-nailed onto the beam, but it had evidently blown off in the wind at some point in the past without anyone noticing. That made for a convenient point for the entry of water as you may well imagine.

Additionally the old gate was constructed quite extensively using plain metal rods, lag bolts, and so forth, and their corrosion made for both difficult disassembly and extensive staining in adjacent wood areas. The combination of the metal fasteners, poor flashing, and placement of timbers right at soil level meant that in the end I was unable to recycle any significant amount of material from the gate. Anything that was free from rot tended to have oxide stains. That was too bad.

So when I had the opportunity to redesign the gate, I pushed long and hard for a roofed gate instead of a kabukimon, as a roof greatly extends the lifespan of the wooden elements below. In then end, for reasons I won't get into here, the decision was made to replace the gate with one of the same type, however they did agree to foundation improvements which would bring the wooden parts up and off the ground. The construction of the gate, and subsequent installation occupied many posts here at the Carpentry Way over the winter of 2014~2015. I'll forever remember that winter, given my unheated shop, as it was the winter of the 'polar vortex' and my shop was incredibly cold for an extended period.

Here's the gate at the time of the opening ceremony and dedication:

Sharp eyes will notice many differences in proportion between old and new. These changes were not arbitrary, or made blindly. The old gate had kinda weird proportions compared to classic forms I have studied, and my design is much more aligned to the classic form of kabukimon, not that the design of gates as such is something set in stone and can never be varied.

Note that at the bottom of the posts are black 'shoes' which are pieces of copper flashing. These are there in effort to simulate the appearance of the black metal plates on the old gate, however I had argued against putting them on at all, as they do not enhance durability in any way. Rather they trap moisture. Similarly, I argued against the use of decorative nails on the faces of the door and flanking section panels, as I knew that seasonal wood movement would persuade them loose over time. Indeed, on the old gate, many of these decorative nails had fallen out and had been lost. Though they listened to my arguments, in the end I was asked to put the 'shoes' and the decorative nails on the gate.

I don't make the above observations to say "I was right and they were wrong", but rather to point out one of the things I learned through working with a large institution: mine was one voice of many, and though "building it to last", "wise use of materials", "sustainability", or "building it right" might seem like darn important things, in the bigger picture they often get steamrolled over by other concerns from other parties. Those concerns might be real or they might be imagined, and they are often political in nature, but they carry weight all the same with those tasked with making final decisions. Greater weight than my arguments anyhow.

So, last year, many of the decorative nails were coming quite loose and falling to the ground, being removed by patrons, lost in the grass, etc.. They let me know about it and I obtained a hundred more decorative patinated nails and their caps from Japan, and put replacements in for the ones which had been lost. However when doing the replacement I filed notches in the nail shanks and put a dab of construction adhesive on, and this seems to be keeping the replaced nails in position for the time being. A year later they remain in place.

Last year, the rear gate posts had swelled more than expected and the sheet copper 'shoes' were wrecked, so I replaced them with 2-piece shoes to accommodate the amount of movement that was taking place. These have worked well so far.

This year, one of the wettest in this area for many years, one of the main gate posts swelled some 1/4" in width and this wrecked the 'shoe' on the bottom, necessitating its replacement. Maybe I could have foreseen this, but really, it was more than I expected. Again, I came back with a version of 'shoe' flashing composed of multiple pieces to accommodate the greater-than-expected movement.

The other main gate post, while it has swelled some amount, did not swell nearly so much as it's partner and the copper 'shoe' there is doing fine for now. Also, both posts have only swelled at the bottom, where the effects of precipitation are the slowest to pass. The copper caps atop the posts remain undisturbed by wood movement it would appear.

So, here we are replacing that post 'shoe' on a fine day in Boston::

I apply some construction adhesive to the inside corners, so as to fix the copper piece to the arris of the beam, allowing for wood movement therefore at the middle of each post face:

Tapping the first piece into position:

I made an exact replica of the post's lower end for the copper fabricator to fit pieces to, and as a result the fitting on site went without a hitch:

Tapping the hinge fixing pin an its escutcheon back into place:

Then some decorative nails, notched and with a dab of construction adhesive, are tapped into some pre-drilled holes:

These connections will accommodate about 1/2" of post movement on each face, far more than it should ever see.

As mentioned, the flashing on the other post was doing fine, which was a little odd to me since the post on that side was far more unruly in its movement during the cut out phase than the one which had done all the swelling:

A few general pics from around the gate now. I'm pleasantly surprised at the good overall condition - it's weathering nicely:

All the framing joints remain nice and tight. If it weren't for urban grime generally, the gate would be a lot cleaner in fact:

The benefit of hand-planed wood is clear, when you run your hand along a weathered piece and it still feels quite smooth and does not evidence raised grain:

A pleasant visit concludes:

All for this time. Thanks for visiting the Carpentry Way.

Tuesday, September 12, 2017

BCM 2017: On a New Track (5)

Last post in a series describing some repair work on 4 sliding paneled doors, or ita-do, and related sliding track, for the Boston Children's Museum.


Today was install day, and that meant a 2 hour commute to Boston, one of the least drivable cities on the planet in my experience (not that I have driven in every city on the planet!). I allowed extra time this morning for the drive, which was fortunate, because one of the routes close in to the city resembled a parking lot for a good stretch of time. When I got to the museum, the parking lot I normally access was being dug up by the City of Boston, and after some fruitless searching at two other parking lots, one full and the other too low to enter, I ended up parking about a mile (1.6km) from the Museum. All in all, that put me about 50 minutes behind schedule from the start.

Fortunately, all the steps went smoothly. The first part of the work, and the part which i thought contained the greatest potential for time-sink, was the removal of the old track. I guessed that it was probably going to be extensively nailed from the backside, which was unaccessible without dismantling a lot of things, so my strategy was to sacrifice a carbide saw blade and rip cut the entire track, snipping as many of the nails as I could in the process. This approach proved to work very well - here, I've finished the cutting and with the aid of a long pry bar I'm starting to pull one half of the track away from the rest of the framing:

The other side came out without much more in the way of complaint:

With the track removed, I pulled any remaining exposed fasteners, or trimmed them off flush with my angle grinder and cut-off wheel, and that left me a clean deck to work with:

The track was relatively trouble-free to fit, requiring only a small amount of scribe fitting to the left post, which was twisted slightly out of position:

In the west, the drawing techniques for fitting a sill between irregularly rotated posts is termed 'tumbling', while the Japanese cluster it in generally with scribing, or hikari-kata. It's a useful technique to have in one's bag of tricks.

Once the track was secured in place, I commenced working on putting the doors. I had left the stiles a few mm long in case significant adjustments were required, and it wasn't too long before the first couple of doors were in place:

A short while later, all 4 doors were in:

I had forgotten to bring any wax, however the Museum happened to have a bar of Japanese sliding door track wax, so I applied a little bit to the track's mizo, and that made for a nice feel in the sliding motion. Here's a look with one of the doors open, though the doors will normally be closed as the 2nd floor is not open to the general public:

The Museum was very pleased with the work.

The process went very smoothly, and took me only a little over 2 hours to complete, including removal of the old track. Then more driving awaited on the commute home, but at least I was ahead of rush hour. That's it for this short series on BCM work for 2017- thanks for tuning in.

Sunday, September 10, 2017

BCM 2017: On a New Track (4)

Post 4 in a series describing some repair work on 4 sliding paneled doors, or ita-do, and related sliding track, for the Boston Children's Museum.


After the frame members were through joinery and finish planed, the stiles received a coat of stain so as to match the rest of the doors:

Rails next, after a coat of stain, which is still wet in the photo below:

The panels and battens had received a lot of wear and tear, exposing raw wood in a number of places, so the four entire panels were given a refresh with stain:

As noted in a previous post, removal of the old frames revealed several broken batten tenons. One of those battens had tenons snapped off of both ends, so I removed the batten from the panel, and placed it in a fixture so I could rout a short mortise for an insert tenon:

Here I'm doing a dry fit of the panel and batten assembly to the two newly made stiles:

The bare patch you can see in the above photo is where the removed batten locates, left off for the trial fit as I know it will fit the mortises just fine.

Everything was fitting up nicely, so I knocking things apart one more time, put the batten back into place, and then glued up using 'Old Brown' hide glue:

Though for many circumstances a 72" rip capacity on a table saw is of limited use, it happens to be an ideal surface for placing a clamped up assembly of about that length :^)

On other panel assemblies, only one batten tenon was broken, so instead of removing the batten to effect a repair, I worked on the joinery in situ using a simple set up like this:

You can spot the just-completed batten mortise in the middle:

At the end of a Sunday, I had three of the four doors glued up, and two of those doors were into a second application of stain. Tomorrow should be the last shop day on this project, and Tuesday is the planned day of install at the BCM. Hope you'll stay tuned for the next installment, and thanks for your visit today! Post 5 is next.

Friday, September 8, 2017

BCM 2017: On a New Track (3)

Post 3 in a short series describing the repair/replacement of 4 sliding doors and a section of lower door track, or shiki-i, for the Boston Children's Museum.


Here are the 8 rails after tenons are trimmed and chamfered:

The stiles have also been mortised - here's a shot of the lower mortises:

The upper mortises feature differential tenon sizes due to the larger/deeper tongue on the top of the rail:

Let's have a look at a fit between upper rail and a stile:


Together and the faces meet cleanly:

A first frame is trial-fitted together:

At this stage, while the fit on the front faces looks fine... actuality the shoulders of the tenon are not fully in contact with the face of the stile:

This is by design, as the chamfers themselves remain a bit short of their final width.

The chamfers were processed on my router table, and a router cut is always going to have scallop marks. Trying to remove such marks by sanding a small chamfer like that, in such a soft wood, is a terrible idea. It seems to me - maybe this sounds crazy -but sand paper and soft woods should generally not meet one another, especially in a wood so easily and pleasantly worked as Port Orford Cedar.

Chamfer size Adjustment? That's where the kikai mentori-ganna comes in:

After an initial pass where a thicker shaving was taken, I reduce the depth of cut for final passes:

Now the fit between the parts was more like what I was after:

All for this round- getting close to the finish line now. Thanks for visiting the Carpentry Way. Post 4 in this series is next.

Some Pointed Remarks

I use Japanese saws exclusively, save for a lone coping saw which sees infrequent use. Some of the saws use replaceable blades, and they work well, while the remainder are traditional saws which can be resharpened. While I have saw files and can, and do, touch up dull teeth from time to time, I generally prefer to send dull saws out to a specialist, who can resharpen, set wayward teeth, and, most critically, perform metate on the blade body to bring the saw blade into perfect alignment and tension.

I gathered a bunch of saws together last year, along with a couple which a friend in Germany had sent to me, and got them together with a box to send to Japan. But then, well, life got in the way, with a newborn, and my shop time occupied with completing two large cabinets, and I did not get around to shipping the saws off until a few months back.

Today I received them back, to my considerable relief. Several of my saws were made by a deceased National Treasure saw smith, and were irreplaceable items, so trusting them to the whims of international shipping and customs was a risk.

They arrived in fine shape, and in a new wooden box:

i had shipped them in a smaller wooden box, however three of the blades I had sent were in fact NOS, and just needed new handles of the correct size fitted. These new handles couldn't fit in the old box, so the agent I used prepared a new box, and he did a very nice job. This is the sort of customer service which is the norm in Japan, and which I have become decidedly unused to since I left that country some 18 years ago.

With the lid peeled up, I was greeted by the sight of the new handles, each numbered to the corresponding saw blade:

The tray with the handles (and one saw blade) on it was pulled out, to reveal the next layer:

And then that layer came out to reveal the next:

The bottom layer had saws affixed to both sizes. Below it was my old box.

After removing the two saws owned by my German Friend, which I shall ship on to him next week, I spent a while tapping the saw handles back on to the blades and hanging them back on the wall. It's so nice to have a bevy sharp hand saws in my possession once again.

Thought it would be fun to share my later summer 'Christmas' present with you all out there. Thanks for dropping by on your journey today.