Thursday, November 24, 2016

A Ming-Inspired Cabinet (79)

Working on the final construction phase of this project, namely the front bifold doors. Bifold doors are by no means common on Chinese or Japanese cabinet, however I have seen a Japanese armor cabinet with bifold doors. Not that historic precedent is/was the only factor driving the design of this piece - far from it. Bifold doors, though more complicated to fabricate than single doors, project half the distance into the room, and the folded assembly can be tucked to the side of the cabinet without running into the wall behind.

When done, the doors will present a wall of bubinga across the front of the cabinet:



The hanging stiles at each corner incorporate a built-in pivot rod, which is offset forward and outward, serving as hinges. These allow the doors to move 270˚ and tuck to the side, unlike traditional Chinese examples, where the door could only open 170˚ or so. There will be quality brass hinges as well, three on each half, which effect the folds. I just ordered those hinges from Brusso, and they will be here any day now.

I re-sawed and dimensioned the front panels from the original bubinga slab about a year ago. The slices were initially dimensioned to 0.5" thickness; after about 6 months of acclimatization in my shop, they were taken down to 0.375" (9.5mm). They have sat since, and remained nice and flat so I am very confident at this point that they will remain that way from here on out.

The panels will be contained in frames and the frames and panel will be tied together and stiffened by way of 4 dovetailed battens per panel. That makes for 16 batters per set, and with two cabinet 32 battens altogether. These will receive shouldered tenons on both ends, so I have 256 faces of material to shave off the ends. Might as well get started on those bits....

The stock was re-sawn, jointed, planed, sat, was re-jointed and re-planed down to finish dimensions. Tenons next. I've cut tenons in a bunch of different ways, by hand and machine, and this time, as with many other junctures in recent months, it seemed like the milling machine might be a good way to cut the tenons.

First off I rough cut one tenon cheek on each end on my table saw, then deck the cheek to the required mark:


Then back to the table saw to cut the other tenon cheek:


Then over to the chop saw to remove waste:


In one of those rare 'time and efficiency' moves (for me!), I lift the stick and drop the waste into the adjacent off cut bin immediately following the cut:


Once all 32 sticks are through to the same stage, I re-set the mill, using the same end stop position, and deck the opposite cheek of the tenons:


This process produced a decently accurate result:


Once all tenons were to thickness, I re-set the mill again, this time to deck the narrow sides of the tenons a slight amount:


I soon decided that a different cutter was called for, and re-set the depth and position accordingly:


The result:


Another view:


Dimensional fidelity was fine:


 The completed batten tenons, from one end:


As you can see, a few of the sticks are flatsawn. That's what happens when you have no more material to pick from, and that's after I spent another $350 on two more bubinga sticks last week. These cabinets vacuum up wood like nobody's business.

I feel like the mill was a good way to tackle that task, and took about the same time as other methods yet with slightly better accuracy.

Below the pile are the door stiles, which are being taken down to dimension over several days and stages of jointing and planing. I really want to keep those parts as straight as possible so the doors will tend to remain flat over time:


The hanging stiles, not pictured above, were cut out, dimensioned, and processed for their incorporated hinge rods a couple of months back. We'll get to those soon enough for mortising.

Next up in this process will be the dovetail trenches on the panels however. And that will have to wait a spell as I am switching over to a Japanese ceiling project with the next entry on the Carpentry Way. Hope to see you there.

I hope my American friends have a great Thanksgiving, and for the rest of the world, I hope your Thursday is as sweet and smooth as can be. Post 80 comes next in this thread.

Thursday, November 10, 2016

A Ming-Inspired Cabinet (78)

Continuing with the description of mounting the demountable frame and panel backs to these two cabinets. The method of using clips so as to make the panels relatively easy to remove, should the need arise, is something I borrow directly from some Ming cabinets.

Some may wonder if having demountable rear panels might be going overboard, however, imagine for a moment you are tasked with refinishing such a cabinet at some later date. One has to agree that it would be leagues easier to refinish the inside of the compartments with the panels out of the way, than with them in place. I detail my pieces, construction-wise, with such people in mind.

In the previous post, I left off after having fitted the back panel assemblies, and getting ready to install the clips. I was debating with myself whether to make the clips obvious to view or to make them more discrete. In either case, the clips are not typically presented to view, as this is the back of the cabinet. I was wondering if I made them unobtrusive if a future effort by some person at repair or refinishing would proceed in obliviousness to the possibility that the backs could be demounted.

In the end, I decided to make the clips unobtrusive. If someone was looking more than casually at the back of the cabinet, I imagine they would spot the clips and apprehend how they worked. At least, that's my hope.

The starting point for the clips is having completed all the mortising for them in both back panels frame members and surrounding carcase boards. The tree panels are held in place with a total of 16 clips, and some of the clips are shared between panels.


After making a first clip on the milling machine, I checked it for fit in its mortise, both axes:



As mentioned, the pattern mill came in very handy once again on this project. This time, I swapped out the jaws on my Kurt D688 vise for an aftermarket type which have a shallow half-dovetailed rebate along the edges. This allowed for a secure grip on the part while decking about 1/8" (3mm) of material off in one pass:


A while later, I have the clips fitted to the cabinet backs, but their heads are not recessed as of yet:


Another view, with the cabinet laying on its side, upper end toward the camera - note the long clips used in the dividers between panels:


After all the clips were fitted, each housing could be enlarged with a step/rebate so as to bury the head of the clip:


A clip in the down position:


Recessing the clip heads allowed the end of the clip to fully protrude:


The excess could then be removed with a flush cutting saw. As this is an exposed face, I took an extra step and used a layer of masking tape to make the cut a hair off of the surface:


One the tape was peeled off, a kote nomi could be used to complete the end grain trimming:


Done:


Here's a look at the two clips holding the bottom rail of the lower back panel:


The clips are fitted sufficiently tightly that they have to be driven in and out with a hammer. They won't come loose in service.

A view of a clip on a stile - I feel these are discrete yet clearly present, not completely hidden or hard to spot:


Clips which protrude through the top of the carcase, as they lie under the cabinet bonnet rail, were summarily trimmed off without the extra masking tape step:


Done:


I'll be sending that saw back to Japan soon for re-sharpening.

A view of a clip trimmed on the cabinet side board:


This view shows the side of the cabinet, giving a look at the modest visual impact of the added clip ends:


The clips could have been left longer and chamfered, for a more overt joinery 'statement', or done blind, with the clip head designed differently so as to permit extraction from the head end. As they are flush, there will be times of the year when the end grain protrudes slightly from the surface, or is recessed slightly, however given the material and the location where it will spend time, we're talking about a hundredth of an inch or so (I have a bookcase in my study with the same system so I've had a chance to observe seasonal movement with the clips for a few years), so it's not something I am especially concerned about.

So, cabinet 1 now is through the fitting of the rear demountable panels and all the associated clips:


The second cabinet is not far behind, as all that remains on that piece is to open up the mortises for the clips so as to allow their heads to be sunk flush with the frames. I'm looking at another 2~3 hours to see that through completion, and then it will be on to the last item of construction, namely the front bifold doors. Woohoo!

All for this round, thanks for visiting. Comments most welcome. Post 79 is next in this thread.

Wednesday, November 2, 2016

A Ming-Inspired Cabinet (77)

Our son turned 4 month's old recently, and he's been teething for the past month. Suffice to say, sleep is in short supply and I've been managing to get just 3-1/2 days per week in at the shop, so progress is slower than I might like on these cabinets. It's a fair trade - nothing more important than doing the 'dad' job as well as possible.

Speaking of jobs, it appears I have picked up a bit of extra work with a project to replace a ceiling in a Japanese tea room located in a house just outside of Boston. I'll be acquiring some Alaskan Yellow Cedar, or Yellow Cedar as I prefer to call it . The tree was first identified and named in British Columbia, it's botanical name Cupressus nootkatensis, after Nootka Sound on the West coast of Vancouver Island, and its range extends down into Oregon, so 'Alaskan' seems, well, slightly misleading to me. I'll also be obtaining some quartersawn Western Red Cedar. The ceiling will be the coffered type, the frame of Yellow Cedar and the panels of Western Red Cedar. More on that project in a separate thread I'll be starting in the near future.

Meanwhile, I've been plugging away at getting the demountable back panels fitted to cabinet #1. Here's a look at the middle panel assembly fitted to the carcase:


Eventually, all three 'demountables' were mounted:


Another view:


A wall of quartersawn bubinga.

How about a look from the front?:


The lower panel will be completely obscured by the drawers. One could argue perhaps that it could be left off, however it serves an important job in keeping dust out of that section of the cabinet.

Once the panels were in place I could turn my attention to mortising for the clips. I originally had left the batten tenons on one side of each frame a fair bit long, piercing right through the outer frame, intending to use them as tenons to hold the frame to the cabinet. I thought better of it however, and decided to trim those tenons flush - it made it simpler to fit the frames closely to their openings instead of making allowance to be able to tilt the panel into position, which would have meant trimming them down in height a bit. In place of those three tenons per side, however I needed to mortise for a larger number of wooden fixing clips than before.

In total, 36 mortises were involved for the three panels. Each panel is fixed by three clips top and bottom, the upper and lower back panel frames are secured by an additional clip on each side, and the middle panel assembly, being the widest, is held by two clips each side.

The clips passing horizontally are shared between adjacent panel assemblies. Here's a look down a mortise passing through the upper frame's lower rail, then the cabinet carcase shelf, and then through the middle panel's upper rail:


If you're feeling a little puzzled by the mechanical aspects of this clip system, I'll be doing a video when I assemble the backs to the carcase later on, and that will make it perfectly clear.

Here's a look at the two mortises for the middle panel assembly's left side (viewed from the rear) fastening:


The clip mortises on the top of the carcase:


The clips themselves will be fabricated soon enough, however I will have to do the same process of panel assembly, fitting, and, yes, the 36 clip mortises for cabinet #2 beforehand.

As these clips will fit to the rear surfaces of the cabinet, the entirety of which goes against a wall and is unseen, I am thinking it might be an idea to leave the heads of each clip proud of the surrounding frames, rather than recessing them as I might do more typically. I'm thinking that by leaving the clips exposed in a more obvious way, it will be more apparent to anyone in the years ahead how the clips work, and that the panels can be readily removed. If they are fully recessed, it might not be noticed that there is any provision at all for demounting the panels. That's what I'm thinking today, but I could change my mind yet! Trying to think ahead 50 or 100 years, and more, involves a certain amount of guesswork of course. Many people today are quite unfamiliar with wood joinery, so I wonder if it will be at all on the radar of a person working on this cabinet in 2116? I put the demountable panels in to facilitate making drawer adjustments, modifications, etc., however if the person repairing the cabinet does not even notice that the back panels can be demounted, then, well, it would be a message that was lost over time I guess. Still worth doing though, in my view.

Thanks for visiting the Carpentry Way. Post 78 is up next.