Friday, December 29, 2017

Dark Chocolate and Sponge Cake (4)

I notice that this is the 999th post in the history of this blog. Funny how things add up after a while.

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I hope readers out there had a relaxing holiday break of some sort.

I haven't been in my shop much of late, what with the time of year, having had a cold, completing the renewal of my Construction Supervisor License by way of a 12-hour online course, plus working on a couple of different drawings besides the cabinet, and, last but far from least, I haven't been there simply because of the unpleasantness inherent to working in an unheated shop.

I did put in a little time there yesterday, receiving a second shipment of the Florida Mahogany:


It's around 180 board feet, all 6/4 and 5/4 save for one piece. A couple of these boards will be used in this cabinet project, while the rest will go into inventory.

Another piece of project stock arrived as well, namely this 12"x12" square of 0.25" thick nickel silver plate:


Nickel silver, aka German Silver, is actually an alloy of copper and has no silver present. I'm going to use this piece, larger than I needed but the smallest piece I could buy from the one supplier that carried plate this thick, to fabricate the door hinges for the cabinet. I am fabricating the hinges because I am unable to find something commercially available that does exactly what I want.

This week, and the next, is shaping up to have temperatures below freezing, and that is certainly not tempting me into going to the shop for any length of time. I've become averse to the prospect, and that is largely due to my past experience spending extended periods in the shop when it is so cold, namely the winter of 2015 when we had the infamous Polar Vortex phenomenon. One day during the MFA gate project I was turning over one of the main posts and felt something give in the fingers of my right hand. That injury proved a persistent one, and I was still feeling it from time to time, even in warm weather, some 9 months later.

Then last year, while it was a fairly mild winter, I managed to do a similar number on my left hand, not as bad as what I had done prior to my right, but bad enough that it lingered for months. When I strained my left hand, I had no idea what exactly caused it, all I know is that it started to hurt, felt decidedly weak, and took a long time to get better. I'm getting a clear idea now that working with my hands in cold temperatures is not something I should do if I can help it. I find that after just half an hour in a cold shop that my hands start to feel achy. I wish I had a warm space in which to work at this time of year.

In the shop I can wear gloves for some activities, put hot gel pockets in my clothes, but I can't wear gloves while operating machinery and generally need to have bare hands on the wood and the hand tools for a lot of tasks. So I end up warming my hands frequently, either with warm water at the sink or by putting them in front of the infra-red heater. I've been thinking an electrically heated jacket might be a plan -or maybe a trip to the Bahamas....

Speaking of electric heaters, I put my infrared one on for the first time while bringing the mahogany into the shop, and as I have not been in the habit of using it, I also am not in the habit of turning it off either. I woke up at 5:00 am the following morning and realized that I had left the heater on at the shop for hours and hours. While it is not a fire hazard, it is a gobbler of electrical current, so I was on the road at 6:00 am to the shop, a 30-minute drive, to turn the heater off and not run the electrical bill up anymore than necessary. Then back home again - the morning is to be spent with my young son before I take him to daycare mid-day.

Because of the lack of winter heat and the distance away from my desk where I do design work, I'm think of ways to change my shop situation, and some plans are underway. The may well be something more concrete in the next 3 months, we'll see....

Speaking of design, one thing I am wishing to do on this project is complete the drawing to every last peg mortise and detail, and am putting together a pile of take-offs (sketches), before doing anything with the wood beyond basic rough dimensioning.

Why the new approach? In the (distant) past I've done work from a pencil sketch, and as issues came up in the build I found solutions to those things that come up which the single sketch did not  reveal - a lot of folks work this way. The door hingeing on a walnut vanity I built in 2005 or so springs to mind. A solution was found, but were I to design again I would have avoided making doors with curved hinge stiles in curved openings. Every project seems to have some minor aspect which becomes a challenge to deal with once it springs up.

With more recent project work, I draw the project using CAD, which I find to be most advantageous for the most part.

I've found though that the littlest overlooked detail - the one thing you assumed was straightforward and you didn't need to wring out every detail in the drawing - that is the thing that can come back to bite you in the ass if you haven't fully considered it. The fitting or action of a piece of hardware, or a decision to add a chamfer to an edge can have all kinds of unexpected associations that sometimes lead to compromises in the finished piece that would have preferably been avoiding if only you had stayed with the design aspect just a slight bit longer.

Basically, I am trying to 'see' everything in the route ahead before I start driving it (fabricate). See all those boulders in the river and moves from one to the next all the way to the other side before we start hopping across. It requires being patient when you are otherwise jonesing to cut something up and get it moved along. I'm sure I will fall short of doing this perfectly, but the effort does count perhaps.

So far, just staying with the drawings further than I typically would previously, resolving details to a finer granulation, has lead to a cascade of revisions to nearly every part dimension. The cabinet looks identical. Just little changes for the most part, 1/16" plus or minus, here and there, but it can add up. Some of this process has come about because my forays into resawing the mahogany for panels lead me to use the 'plane it down' method to obtain many of them, and for the ones I did re-saw, the construction for many of the panels now will be with 2-piece panels, not 1-piece. The necessitates changes.

I have also revised the drawer construction detailing slightly:


The floor, sides and rear wall are of Honduran Mahogany, while the drawer fronts will likely be shedua, as illustrated. The changes are in the joinery at the front of the box, and in the form of the side pieces.

These are now the third iteration of my drawer design (begun on the 'Square Deal' side table, then taken in a slightly different direction on the 'Ming-Inspired Cabinet'). This time, the drawer sides and runners will be formed as one, machined from one piece of material, instead of taking two pieces and joining them with a sliding hammerhead connection:


This 1-piece 'I-beam' construction is a little bit stronger than what I was doing previously, and allows the drawer sides to sit further outboard, which in turn modestly increases the interior volume of the drawer. By machining the drawer side pieces and their runners out of solid rather than joining two pieces for each, I can radius the transitions, which again increases robustness and makes the drawer interior a little easier to clean. The contact between the side of the drawer and the side of the opening is still minimal, and the wide running surface for extended durability remains.

In place of the usual view of dovetails one comes across, the is the exposed drawer corner on this cabinet:


I think that looks sufficiently pleasing and interesting - I hope you'll agree it's not too 'busy' at all - and definitely conveys that joinery is being used to put stuff together, for those who might notice or care about such things. The drawer sides being further outboard and 1-piece also opened up the possibility to do a half-blind dovetailed connections to the drawer front, but I prefer the wedged through tenons all the same.

I should be back to material cut out work on this cabinet sometime in the first week of January. In the meantime I think I'll post again on design aspects for this piece. Now you know what's coming, you know what to avoid I guess. :^)

Thanks for visiting the Carpentry Way. All the best for 2018 if I haven't posted before the 1st of January.

7 comments:

  1. Hello Chris !

    What can I say ? just wonderful to see your blog as always and happy to learn what is impossible to see in any other site of the net. Please have a great holidays, merry christmas and my best wishes to the new year !

    From spain your devotee Julio

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    1. Julio,

      thanks so much for your kindness. While I'm certain there are far more interesting woodworking blogs out there, I'm glad you enjoy visiting here too. All the best to you for 2018 as well!

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  2. I'm looking forward to seeing what you create with the nickel silver. It's a material that I always associate with musical instruments. I know you take much of your inspiration from Ming style furniture, I know for a fact that they also employed halfblind dovetails in their pieces. I think it's an interesting task that you trying to reinvent drawer geometry. I am trying my very best to not leave a comment along the lines "why don't you do it this way".
    I suspect that the mortise of the lower M/T joint is an extension of the groove that will receive the drawer bottom. Since you don't want to put a similar groove along the top part of the drawer front, this necessitates two stopped grooves per drawer front, which is something to be avoided. In my best diplomatic jargon, I ask: 'have you considered attaching the sides to the drawer front with two halfblind dovetails at the thicker sections of the drawer front? It can also be possible to add a rabbetted edge that the tailed sides slide up against to eliminate any gap developing over time.
    I want to ask you also about your idea of secondary woods. I've seen modern Chinese versions of Ming furniture that are completely made of Hongmu species: drawer fronts, sides, backs, and bottoms. These create very heavy drawers, which say more about the expense of the piece and less about the design and function, relating to giving the clients what they want even though the clients don't know what they want. This might be less diplomatically worded, but are you choosing to use Honduran mahogany because it's what your clients expect rather what might make for a functional drawer? Again, I enjoy the efforts you put into your craft and your willingness to share the process.
    Happy and prosperous new year to you and your growing family.
    -Mitchell

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    1. Mitchell,

      thanks for your comment.

      The use of Nickel silver is very much in line with Ming period work, where paktong (白銅) was employed, paktong being essentially the same thing as nickel silver. In fact, German metalworkers developed nickel silver in effort to copy paktong in the mid 1700s.

      In response to your comments about my drawer designs, well, for starters I am not trying to "reinvent" drawer 'geometry'. I am taking an idea from the 1950's, the NK drawer from Scandinavia, and executing it with some refinements of my own. NK drawers were done in a version which had half-blind dovetails at the side. I happen to find dovetailed drawer sides a little tiresome as a motif, and want to do something different, though i have considered doing the half blinds all the same. I know that Ming drawers employed dovetails, though drawers are a bit uncommon in Ming furniture in general. After reconsidering, I choose to do mortise and tenon again. The drawer front to side connection is no weaker as a result, and it is no more difficult to execute in cut out, so why not?

      As to, "...this necessitates two stopped grooves per drawer front, which is something to be avoided" - why? The groove in question is simply a shallow extension of the mortise cut into the drawer front to receive the drawer side tenon. There's nothing forbidding or daunting about cutting a stopped groove, any more than there is in cutting the mortise. If I were thinking to cut the grooves with a grooving plane, that would certainly be a tool ill-suited to the task, however I'm using a router, or my milling machine, to do it. Even if i chose to only use hand tools for the task, cutting a stopped groove for all of 3/4" is a simple task with a chisel.

      Secondary woods: sure, i've thought about this a fair amount. I still may employ avodire for the drawer sides, pending upon whether I choose to spend some additional money on that or not. As the design stands now, I'm using Honduran mahogany for everything but the drawer fronts. It's not a heavy wood, rather a medium weight wood. I fail to see how the use of Honduran Mahogany will make the drawer significantly heavier than if I made the parts from plywood or pine, say. How is Honduran mahogany in any well less functional than any other species? This makes no sense to me. In fact, due to how superbly Honduran mahogany behaves in the stability department, it is rather an ideal wood for drawer parts I think. It is an ideal wood in which to cut joinery. It is quite stiff and strong relative to it's weight, which makes it ideal for all parts in drawers.

      I might add too, that in terms of what is conveyed by the shedua drawer fronts, which otherwise are suggesting to the viewer that the entire drawer is shedua (which, with drawers as large as these, would make for heavy drawers), the use of Honduran Mahogany for the rest of the drawer parts is in fact their use as a secondary wood.

      I choose to use Honduran mahogany for the drawer bottoms because the very wide stock I chose to buy for the project allows me the luxury of doing the drawer bottoms in one piece, almost all quartersawn, instead of gluing up boards or recourse to plywood. The main reason secondary woods were used in the past is to economize on costly material, however I do not see that point of that argument here. Honduran mahogany is in fact the least expensive wood constituting the cabinet, and the price point of the cabinet is enough that such economies are not, well, merited. I am not looking to cut corners in my work, though many makers in the past, east and west, have been forced to do so or, perhaps more often, have chosen to do so. I object to the idea that putting cheaper woods in places 'the client doesn't see' is somehow virtuous - rather I see it as quite the opposite in fact.

      In answer to your question then, I chose to employ Honduran mahogany for the drawer parts because it is a highly functional choice and this decision involves no input from the client.

      ~C

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    2. To follow up from the preceding:

      If the question is whether Honduran Mahogany is a good functional choice or not, we have to address what 'functional' means exactly. If it is in any way connected to the idea of 'fitness for purpose', which I think it is, maybe more than any other aspect, then what determines such fitness?

      To me, in the case of a drawer, the performance of a wood is a combination of how good it is in compressive strength, stiffness, and in bending strength, all relative to how dense the wood is.

      If you look at this page: https://www.rtcmade.com/2017/08/30/why-birch-plywood/

      you will find an analysis of such things with various domestic wood species in the US. He found that Hemlock had the best compressive strength relative to density, and that hickory had the best ratio of bending strength to density, comparing among 32 species.

      If I plug in the values one can obtain for Honduran Mahogany for compressive strength, density, and so forth, it comes out 2nd on his list for ratio of compressive strength to density, and 4th on his list for ratio of bending strength relative to density. And it comes 10th on his list when looking at the ratio of stiffness to density.

      All in all, I don't think there is a better all around performer than Honduran Mahogany, and that is without factoring in its reasonable cost, availability in a wide range of sizes, easy workability, excellent stability in service, and excellent rot resistance. Comparing the overall score for Honduran relative to that list on that fellow's site, it comes in second overall to hickory, which, after all, is not available in wide quartersawn or thick configurations, and it has poor durability.

      I would be interested in comparing Cuban Mahogany with the Honduran in the above respects, but getting data points from which to conduct any analysis is a problem. I wouldn't use it for drawer interior parts anyhow, as it is too precious for that.

      ~C

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  3. Aloha Chris,
    Sorry to hear about your finger injuries. I commiserate as I had my first tendon injury over twenty years ago. I'd like to think that 3 more injuries later, I am more careful. We don't have that kind of cold here, but working on the big wood solo will never-the-less always involve risk as we get older. (Read up on drummers like Max Weinberg's struggle with tendinitis.)
    So I "planned" a transition strategy to work "smarter, not harder" that is still evolving. Since Oahu is a competition to stay on the island and costs are high for shop space and overhead, I had little choice. With 9.5 million of my closest "friends" visiting every year, tansus are working out. As you pointed out in earlier posts, hardware is the key. So making my own keeps me ahead of clones, and bridges the gap between jewelry and furniture. And I can ship world-wide.
    But I digress. Take the time to warm up and prepare your digits for work and read up on reducing stress related injuries (if you have not). I have a little arthritis starting up where the old injuries happened, but I think that I will be OK for a while. Time wins in the end.

    aloha kakou,
    Karl

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    1. Karl,

      thanks for the comment. I'm not entirely sure what the injury to my fingers is. It's weird, not exactly like a tendon strain. I think the idea of warming up is a good one, and I do try to do that, including keeping the heat blasting on my hands during the drive in.

      But, if I can do paid work at home, designing and drawing, etc., then I will do that rather than skulk around in a freezing shop.

      Glad to hear that you've figured out a way to stay afloat in the furniture business. It's not easy.

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