Friday, April 21, 2017

A Ming-Inspired Cabinet (94)

Now working on fitting the bifold doors to the client's cabinet, adjusting door width at the sides of the stiles, as before:

A shot of one of the shavings through a tenoned area of the stile, just for kicks:

Planing is satisfying when it is going smoothly. Doors are now fitted to the second cabinet (not illustrated).

On a door-related matter, I purchased the door and drawer handles from Japan, and they come with plastic 2-part cups, as shown below:

The one half of the plastic cup, is like a washer under the nut. After the nut is tightened, the excess threaded rod is snipped off, and then the plastic cap is snapped into place.

I'm not too excited by the plastic bits for these cabinets, and started thinking about what alternatives might be worth a look. For the door handles, the threaded rods can be unscrewed, so it seemed to me that they could be replaced by a countersunk allen button head screw. I looked at a few online bolt supply sites and noted that the closest thread sizes to what I thought I had were M2, M2.5, and M3. I was suspecting these threaded rods were M2.5, however when I got to the shop and put the caliper on the thread, I got a different value:

That does not correspond to any known metric thread standard, including JIS metric thread standard.

I took the threaded rod and nut to a local hardware store to see if I could find something which was the same, and the closest I got was inch-scale #4-40 threaded fasteners. Checking into these later, the standard for diameter for #4-40 thread is 0.1120", which works out to 2.8448mm, pretty close to the caliper measure shown above.

I'm not however totally convinced that the Japanese handle threaded rods are sized to #4-40. It is not far-fetched to think that they might use a non-metric thread standard, as I've seen Japanese circular saws with a 25.4mm arbor (=1"), and found the lock cylinder on a Japanese temple lock to also be inch standard. But, I'm not sure in this case what to think. While a #4-40 threaded rod will fit the brass nut, and the Japanese threaded rod will fit a #4-40 nut, when I tried to fit the Japanese threaded rod to a #4-40 acorn nut, it wouldn't thread in, while a #4-40 threaded rod would thread in to the same nut. So, there appears to be a minor difference in the threads between the Japanese parts and the #4-40 stuff. A bit of a puzzle.

In any case, the threaded rods going into the Japanese drawer handles are more firmly installed, and not easily removed, so it looks like I will have to go with them after all. The handles on the doors could be swapped out for allen bolts however, using #4-40 parts. I'll give this matter some more consideration before doing anything further on this. Funny how some minor things like that can turn into more of a trouble than one imagines initially. Why one earth do they feel the need to use an odd thread size for something so mundane as drawer and door handles? The mysteries of life....

Setting that matter to one side, another hardware task needed to be dealt with and that was enlarging the countersinks on the Brusso hinges to accept #6 screws. I initially tried to do this using a countersink in a portable drill, with the previously-established drill hole in the wood as a guide, however this did not produce clean countersinks by any means:

The mill was the way to go, with a suitable fixture for the hinge the only hitch. I put the Kurt vise back on the work table, trammed it into alignment, placed a block of bubinga in the vise, and then milled a pocket in the block to accept the hinges by friction fit alone. This milling was done with a 1/2" down spiral carbide bit to leave clean sidewalls.

The milling was done from a 0-x and 0-y point, so I had a ready means of finding the offset of the screw holes without trying to measure them directly on the hinge.

I have a set of Weldon 82˚ countersinks to draw from for this task:

This is the 'piloted' set, though the 4 smallest lack pilots. I find these countersinks cut very cleanly. USA made and everything.

With the countersink fastened into a 1/4" collet, I moved the table over 0.75" from the 0-x point, which brought me to the middle of the hinge. The DRO was then reset to make the middle the 0 point for x-travel. Then I simply moved over the y-travel to a point which corresponded to an even inch measure from my starting point, 0.3125" in this case. I strongly suspected that the hinge holes were spaced on some even imperial inch measure from the hinge edges. And they were.

Here's the first countersink:

I moved the table over so I could put a fastener in to check if the countersink was deep enough:

It looked good I thought:

Once depth and positioning was set, all the hard work was done. I now shift the table on x-travel to the next countersink location, in this case, 11/16" away:

Then countersink:

Then shift back to the other side, which is also 11/16" from the middle:

Drill again:

Next, shifting over to the other hinge leaf, using y-travel, the hole centers of which turn out to be 7/8" away from the first line drilled:

Similarly, the other holes on that side are drilled by shifting along the x-travel by 0.6875" each time:

The hinge was popped out of the fixture and it was time for a final check back at stile central:

Zero issues:

Any further pre-drilling into the wood that was required was accomplished, as before, using a suitable VIX bit:

That process, without putting all the screws in mind you, was repeated for the other 11 hinges. The hinges are now all done, save for another bit of patinating and a final application of wax. Another tick off the list.

I set the bifold doors and their hinges aside for the time being and moved on to the bonnet components, looking to complete them and do a final assembly on that unit. First task was to give a final clean up on the curly shedua stand-offs, which I did on the super surfacer, then a last check for fit of those parts onto their sills, and then I could kerf the tenons on the intermediate pieces and mask off around the mortises in preparation for a glue-up:

Wedges also needed to be made - here I'm checking them for thickness at the tenon sides:

More wedges remain to be cut before the glue-ups can proceed, so I'll tackle that task next round.

Thanks for visiting the Carpentry Way. Hope you enjoyed.

Tuesday, April 18, 2017

A Ming-Inspired Cabinet (93)

Doors, doors, doors...

Fitting the bifold doors has taken a fair while. Small adjustments were required to the frames of the doors respective of the carcase opening, as well as adjustments along the doors stiles to create suitable gaps between the leaves.

Here I'm giving my Genmyō plane a workout on one of the inner stiles:

After adjusting the inner stiles of each pair of bifolds, I set them up together with a slight space between stiles, shimmed with 0.01" gages, and then mortised for the three hinges using a router and small pattern bit followed by chisel work:

These are 1.5"x2" Brusso hinges, which are good quality however they come with rather tiny #4 brass screws. They provide a steel screw to pre-thread the holes, however in bubinga, even the steel screws are a tightrope walk in terms of fitting them without breakage, never mind the brass screws, which combine material weakness with a cursed Phillips head. Breaking screws off in hinge holes is a territory I prefer to avoid, having visited previously I will say it can not be recommended as a destination resort.

I dump the screws that come with the hinges and go for stronger #6 screws with a Robertson head. These require that the countersinks in the hinges be enlarged slightly, however for trial fitting purposes, a single screw on each side, although protruding, will suffice so long as I do not fold the doors completely up to one another:

I patinated the hinges using a gun bluing chemical.

At last the bifold arrangement can be mounted on the cabinet:

At this juncture the fit is a hair tight, as intended, between the pairs where they meet in the middle. I will make further adjustments of course until the operation is as it should be.

A view with the doors open a bit:

The green tape on the right set is to aid in opening the doors when together.

Another view:

A closer look at the exposed surfaces of the inner stiles and hinge pivots:

Because bifold doors can be put together by swinging and sliding movements, or a combination, I will need to consider carefully how best to deal with the junction between doors in the middle, along with how the doors will latch into position. I've been mulling this matter over for months now, so I do have some ideas and there are various hardware options.

All for this round. Hope you enjoyed the visit! Ready for more? Post 94 follows.

Friday, April 14, 2017

A Ming-Inspired Cabinet (92)

Final post in this thread - - just kidding!

Moving along, moving along. Before I could bore out for the hinge bushings on the support stand's sill, I had to assemble the sill frame together. The corners on the frame are Japanese mitered box joints with shachi sen, and this corner you see next was the first to be done, and incidentally was the one shown in the previous post, with my assurances that the miter gap would be gone once the pin was in place:

I originally had fabricated ebony sen for these corners, however I found upon driving that first one in that it had an internal flaw which lead to it splitting. Not a particularly enjoyable outcome, and it took a good while to extract the split pin sections from the confines of its mortise.

That left the task of making new ones, which I chose to make out of bubinga. One of the problems with ebony is it can often have internal fissures and splits that may not be obvious after cut out is done.

Again, I turned to the milling machine for the task of tapering the pin thickness slightly over its length (about 1/32" over 6" in this case). The sen were affixed onto a piece of aluminum plate with double-sided tape, and the plate itself canted in the vise jaws by way of a feeler gage. The milling went very quickly:

This is a simpler and method than used previously, also on the mill: see Post 23.

The pins were then made into parallelogram sections and tapered for width using a shoulder plane, and fitted, one by one, to their respective corners and driven home. They will be left long for the time being -- maybe for good.

With the bubinga sen installed the hinge bushings could be counterbored and bored. First, a pointer from a Starrett trammel set is chucked up and used to locate the machine spindle directly over the pricked mark:

Then onto the 7/8" Bormax:

A check to see that the bronze flange of the bushing fit the counterbore:

And then the 5/8" hole was bored to about 0.01" over the required depth for the bushing:

It fits!:

I've been talking a little bit in the past couple of posts about tool holders and collets, and thought a picture might be informative for some readers. On the left is an ISO40-taper tool holder with ER25 collet (10mm) and Forstner bit, in the middle is an 8mm ER25 collet, and on the right is a 444E collet, which fits, obviously, a larger tool holder:

Quite a size difference between those collets, eh? Of the two, I prefer the 444E, as when you loosen the collet nut the tool tends to stay put in the collet (though it is easy to slide out), while with the ER25, when you loosen the collet nut the tool can, and will, just fall out. That often means traveling down onto the work, making a mark in the surface (ugh!) or a clear perfect fall onto the cast iron table top, thus dinging the tool point or and edge (ugh!). I've learned to put a piece of scrap wood under the ER25 collets before loosening the collet nut, thus giving the tool a landing pad of sorts.

The next day I'm back at it on the mill, this time, after the usual preliminary milling steps, forming some ebony blanks into wedges:

This sort of job, for just 8 wedges, can be tackled in various ways, using hand saw and plane, with a jig to hold the wedge in place for planing, or by way of a tapering jig on the table saw or router table. I think the mill is the best way to do it however, as the piece is held absolutely rigidly, and can be milled at the precise angle required, and it is dead safe as your fingers never get near the cutter. Quick too: ll I had to do was cut a slice of MDF at the required slope and fit an aluminum stop into one of the vise jaws and cutting could proceed.

The roughed out wedge, number 1 of 8:

The wedges were taken down in size over a couple of stages.

Later, the wedges could be applied to the ends of the hammerhead draw bar pins, so as to fix the support stand sill to the bottom of the carcase:

At this point the wedges are left just a hair fat, so they don't enter as far as they ultimately will. They are also over-length:

One side in a closer view:

A while later both cabinets were through to the same stage:

Then the cabinets could be stood up so the bonnet cornice pieces could be fitted on top onto their dovetail keys and slid into position, then bolted:

A cabinet back down again and - what's this? - some hardware being applied to the upper end of a hinge stile:

At last, the first cabinet has its outer doors (trial) fitted!:

Just a check to show how the door can swing a full 270˚ with the offset hinge rods:

Now, I knew it would make the swing as I had designed it that way in CAD, but sometimes one feels a need to check that it really all works as it should once built., where the virtual meets the real.

The two middle panels could be just squeezed in to the middle, however a little bit of fine tuning will be required as there need to be slight gaps between door leaves:

And here's the client's cabinet, through to the same stage:

Another view of the first cabinet with a different camera setting:

I feel a certain milestone was passed today, and feel good about where the project stands. While the doors are not complete by any stretch, the end is in sight and I think I should be able to make the required fitting adjustments and install the hinges for the inner door leaves in the next couple of shop sessions. That will leave only a modest amount of construction work to do, and mostly a bunch of finishing and hardware installation. Nearly there....

Thanks for visiting the Carpentry Way - comments most welcome. If you want to read further, Post 93 is next.

Wednesday, April 12, 2017

A Ming-Inspired Cabinet (91)

Today's work began with some simple hole drilling in 1/2" square aluminum bar stock:

The bottle contains not water, but denatured alcohol, which I use as a cutting fluid. It prevents the gummy aluminum from welding itself onto the end of the drill bit, as it is prone to doing. I picked up the tip to use denatured alcohol from a Youtube video by a machinist in Germany, and it works really well.

The holes are offset an exact amount from one another:

I mentioned in the last post the use of collets, and for those readers who might be curious, here are a couple of the 444E collets, one 1/2" and one 1/4", and collet nut:

The aluminum bar was then chopped off on the sliding table saw, and bolted up to one of the vise jaws with some 1/4"-20 pan head screws:

The little Wiha ratchet you see above is part of a set I recently received for my birthday. After the Japanese ceiling project around New Years', I realized a need for a tiny ratchet which fitted 1/4" hex shank bits instead of the regular type of 1/4" drive ratchet plus socket, which prove to be too large in confined spaces. the Wiha was my choice, and my wife came through with this little metal case of goodies:

It comprises more than 60 pieces, and utilizes a 1/4" hex drive adapter to run tiny 4mm shank bits. But of course one can snap any old 1/4' shank bit into the tool no problem. There is an extension as well as an anti-static diver for use with electronics. It should prove handy from time to time.

The case is made of some nice thick metal too:

The set up complete, onto the woodwork we go. Up today are the hammerhead draw bars which joint the cabinet case to the support stand. The blanks were first prepared by the usual jointing planing resawing and super surfacing, followed by some work on the sliding tablesaw to cut to length and then kerf the pieces crosswise. At the end I had a pile of 9 pieces:

Only 8 pieces are required, however at last, with such small bits of wood, I could afford a spare piece. Such luxury!

The aluminum piece I had made earlier and attached to the vise jaw serves as a stop to register the piece in the vise:

After cutting both sides with a test pass, measuring the result and then adjusting the mill's z-travel accordingly, I milled the pieces. The resulting neck dimension was right on target:

A while later, all 9 pieces were done without mishap:

Next step was to chamfer the perimeter of the hammer heads:

Then I used the sliding table saw with the blade canted over at 22.5˚ to chamfer the small ends of the draw bars:

It's funny when you take the step of planning in an extra stick and nothing goes awry. But, 8 were all that were needs so one went in the trash.

Half of the draw bars were then fitted to the sill crosspiece of one of the stands:

A closer look at a couple of them:

Next step was to fit the same 4 draw bars to the bottom board of the carcase:

When installed, the hammer heads sit in a 3/8" deep recess, leaving a total of 1/4" of the pin protruding:

Next was a step I've been awaiting for quite some time, namely placing the cabinet box upon the stand:

Similar to how I marked out the door hinge centers on the bonnet cornice piece previously, I employed a custom-machined brass transfer pin in place of the pivot pin at the bottom of the stile:

The door is positioned at the correct offsets and alignments, in preparation for marking the hinge center:

The draw bars were all driven down and into position and the location of the carcase relative to the sill was carefully measured to confirm it was where it should. Only minor tweaking was required, which was a good sign.

If you poke your head down below and look up, you can see where the hammerhead bars emerge:

These will be fitted with crosswise wedging pins very soon. I'm thinking I'll use Gabon ebony for those wedges, if I have any kicking around.

Anyhow, the perfect world of the drawing for this cabinet had the hinge centers falling exactly upon the sill miter lines. I was curious to see how close i got to those lines after all the fabrication, of the sills themselves, the carcase, the hinge stiles on the doors, and the hinge pin centers on the door stiles.

The left side miter line first:

Don't worry about the miter being slightly open, as the locking pin, or shachi sen, has yet to be driven into that joint. They will close up nice and tight soon enough.

The right side miter line was just missed by a hair with the center point:

Overall, I was very pleased with the way things turned out today:

While I was working on the above, interspersed were rounds of finishing work on the bonnet cornice assemblies which I had started last time (not illustrated). At this juncture, they have 3 coats of finish. I plan to put 5 coats on the very front edges of those assemblies, so these should be done in another day.

Tomorrow I'll repeat the same process of assembling carcase to stand and marking out the door centers on the stand's sill miters. Once that's done I can proceed to drill out those places for the bronze bushing which will be fitted. I can also complete assembly of the sills themselves and get them into finish.

Thanks for visiting the Carpentry Way. The next post is #92 in this series.