02 February 2015

Gesso

I have known about gesso as it relates to gilding and how to expect it on antique furniture, but I had never gotten around to working with it nor discovering its potential. It represents one of those well established methods of woodworking that fell out of favor with the advent of industrialism and plastics, in particular. And as with so much of woodworking of old that has been experiencing a revival, I think gesso has potential to follow this trend.
Initially I was planning on following the method that Pfollansbee uses to attach hinge battens to a 6 board chest lid: clenched nails. I ended up having to use Scotch pine glulam for a lid, which made me reconsider whether clenched nails would be appropriate or effective. I thought first about countersinking the underside of the battens and attaching the lid with woodscrews. The thinness of the lid stock made me hesitate. I had finally found a source of hide glue in China and the idea of gesso as a filler seemed to arise sua sponte.

I had already marked off the spacing but had not predrilled the holes for clenched nails. I instead drilled the pilot holes for the screws and then countersunk for the screw heads below the lid surface. At this point I was committed to using gesso even though I had not quite figured out how to make it or what to expect from it. Online resources focus on gesso as sizing for preparing paint surfaces on wooden panels, which is a good start and better than nothing. I bought both plaster of Paris and chalk dust, but I have not yet experimented with the plaster of Paris. I also bought the chalk dust as an additive for milk paint, but I have not been using it for that.

There are some guidelines for determining the consistency of the chalk dust/ hide glue filler. The most useful one is to create a mixture that resembles light cream. My gesso ended up as a rather heavy cream but I applied it anyway.
applied to deep countersinks

At about the same time that I was struggling to complete the 6 board chest, I was building a Dutch tool chest. I had glued together some blocks that would be drilled through to accept grommet handles. Some short grain split out, yet rather than curse the arbor gods, I saw another opportunity to try out gesso as a filler.
second application

The tool chest bracket required two applications. Since gesso is a water based filler, as it dries, there is some unavoidable shrinkage. After letting the gesso dry sufficiently. I used a riffler to abrade the excess and then a card scraper. I am still not certain what the best way to bring down the excess gesso to form a flush surface. It can be moistened as I did on the 6 board chest lid to produce a smooth surface. The water also lifted the milk paint, which had to be reapplied anyway.
scraped gesso flush with surface

smoothed with hot water


Both of the surfaces were intended to be finished with milk paints. It might be that as the rise of the natural wood grain aesthetic rose, and the use of painted surfaces fell out of fashion, the use of gesso also dropped off. I was eager to see what the results would be after painting.
painted and oiled gesso infill

smoothed and overpainted


The gesso does not seemlessly fade into the wood surface, but I still like the results and am  further intrigued by what else can be done with it. I have not applied oil to the 6 board chest lid but the results of the linseed oil on the gesso in Dutch tool chest bracket show that the gesso accepts the oil well enough.
I think that adding some glycerin to the hide glue can enhance the elasticity of the gesso to account for seasonal expansion. It might be possible to texture the gesso to make it match the pattern of endgrain. I will also go lighter on the chalk dust in the next batch. It's clear from these two examples that gesso opens up possibilities that I had not considered previously. It complements the the use of milk paints wonderfully. 







09 January 2015

New Screws in New Tools

Toolmaking is a trait by which some have defined homo sapiens. Ours is a tinkering species. I freely admit to this. I've updated two tools from Veritas to make them, in my estimation, better than originals.
This first tool with an opportunity for improvement is the 5/16" Hex Brace Adapter.

Brace adapters.
The 1/4" Hex Brace Adapter is something that should be in everybody's toolbox.  It can accept any and all commercially made 1/4" hex bits. It secures these in the aperture with a small magnet that generally stays in place. I've actually had to reglue the magnets on both of mine with two part metal epoxy. An annoyance to be sure, but until another manufacturer can produce something better, Lee Valley is the only supplier that I know of.
On the larger 5/16" hex model, instead of a magnet to hold the bit securely, a 4mm set screw that requires a tiny flat tip screwdriver was employed. This tool was made available to be sold to accommodate the larger shaft of the Veritas power tenon cutters and countersinks. They either felt that a magnet was too weak or else they had no confidence with their Chinese subcontractor finding a way to keep a magnet from falling out. 
I don't like have to keep a set of tiny screwdrivers with me so I opted to replace the set screw with socket head cap screw. (I actually lost this tiny screw the first time that I tried to use the tool which initiated this idea for upgrades.)The walls of this tool are quite thin so a 4mm, 5mm long screw is all that is necessary. Not only does the circumference on the socket cap make it easier to tighten with finger pressure, if greater torque is required, it is certainly a better fit to use a hex key to turn the screw.

I applied this same idea to another tool that I have recently purchased from Veritas, the wide blade conversion kit for small plow plane. This is a center skate that helps to support wider blades and, in my case, tongue cutting blades for tongue and groove joints. Thinking about it now, I think that the marketers thought that they could more easily introduce the small plow plane with a lower price point by selling the center skate separately. This is a shame because the tool is generally well made, yet it requires a dedicated user with sufficient spare time to figure out its full potential because these components are were sold separately. (I notice now as I write this that Lee Valley has changed their website to avoid some of this confusion since they now offer the small plow plane with conversion kit under a single price, admittedly at a steep price.)

The conversion kit out of the box.

There again is a set screw requiring a tiny flat head screwdriver to engage it. I applied the same thinking and purchased a #10-32 1" socket end cap screw to upgrade the tool. There is hardly any need in this application to apply torque. The screw functions to keep the skate parallel with the main body. It doesn't require force, but rather a finesse that can be accomplished with fingers much more readily than by fiddling with a screwdriver in a little slot. The hex aperture in this application is superfluous.
The center skate installed with socket cap screw


It looks better, too.





08 January 2015

The joiner in the winecellar with the tenon saw!

Shanzhai culture makes wine purchases daunting in the Middle Kingdom. Language barriers and a lack of DOC enforcement make it a constant hazard for even a fairly competent Chinese oenophile to detect the drinks from the dregs. The French wine conglomerate, Castel Group, has been able to enter the Chinese market primarily on the cachet of all things French. As a student once defined the word, romantic, to me: "You know, like France."
The middle class Chinese consumer wants to drink the best that he can afford and has convinced himself that French wines are all the best. And so through the magical process of self-fulfilling prophecy, French imports are typically the most expensive of any wineshop's selection, and the most profitable for shanzhai bottlers to copy.
Shockingly similar packaging

I can only explain the proliferation of special packaging in China as relating to the need to often deliver special gifts to lubricate social connections. Even truly mediocre wines are placed and sold in 'presentation' boxes, sometimes with special latches or corkscrews. This same marketing gimmick extends to chocolates, fruits, olive oils, even to individually packaged milk containers.




Sidebyside the two wine presentation boxes appear nearly identical. Yes, to the trained eye, the smaller sized of the two might have better proportions, but this is only helpful if one is able to view them thus or has studied western design aesthetics. To avoid such deception, a far better method of examining these cases is to pay particular attention to the joinery.


Any knowledgeable woodworker will know the superiority of a box constructed with fingerjoints to one made cheaply with butt glued miter joints. Taking this observation into account can allow any confused consumer to know with a slightly greater degree of certainty that he is buying himself a bottle of Miribeau whether to impress his colleagues, local government official, or inlaws.

06 January 2015

Polychromatic symphony



I came across this mindbending example of woodworking. An instrument based on a sketch from one of Leonardo DaVinci's notebooks, a viola organista. Besides the mechanical challenges posed by building such an instrument, (Treadle powered!) I am in awe of the maker's decision to paint it such bold, primary colors.
View of interior, standing on piano stool
 I cannot find anywhere any explanation as to why he chose to not go with traditional 'Steinway' black. And I doubt the pianofortes in DaVinci's day were of similar hues.



I've been experimenting lately with milk paints on white pine and learning about pigments so this example reinforces how much more there is to surface decoration even though contemporary aesthetics tend to favor the plain, untinted wood as often as possible. Wood for the sake of wood since keeping the grain exposed insures that it is really made of a natural material, right? The average consumer, simultaneously estranged from the craft process, is also bewildered by industrial manufacturers' trickery. Vinyl siding textured with wood grain? To what ends but to deceive.
I salute you, Mr. Sławomir Zubrzycki, your playing as well as your palette.

31 December 2014

Chinese style bowdrill

I managed to snap some photos of two bowdrills that Gao Yisheng brought into the woodshop before his departure. The bowdrills have left with him but my curiosity remains. They function identically yet while one is clearly a smartly fashioned homemade model, the other shows signs that it was manufactured.

side by side

Besides having a surface finish, the bowdrill on the right appears to be manufactured (yet I could find no brand markings) because of the larger alloy ferrule that accepts drill bits or bit pads and the ball bearings set inside chrome plated races. (The ferrule on the handmade version was nearly rusted through.) In spite of this, the bowdrill is rather crudely made. There is a bit of loss where, it seems, a lathe operator gouged out some short grain but it was still deemed acceptable. It's the putative handmade tool that has this detail on the handle that distinguishes it as more refined and adapted by a user for a user's comfort.
The more elegant handle of the two

the ferrules

By contrast the other bowdrill handle is a straight dowel with a wider section for a handle that is also warped along its length. Whether intentionally or not is unknown. I don't know anything of their provenance nor was I able to use them. They arrived as is and without and attachments. The cords were similarly rotten and would have required restringing before attempting to test them.

Planing stop, croche, and bowdrill

I managed to photograph a similar tool while on a woodcraft tour of TianTaiShan.
unguarded combination machine
Bespoke furnituremaker


















I spotted this one on the workbench of a furnituremaker. He seemed to use it exclusively for drilling the alignment holes when gluing edges of wide boards. Opposite the work bench, he used a jointer with a drill chuck attached to the cutterhead spindle as a horizontal borer. The main source of lighting came through the front entryway so I failed to get a good photograph of the drill bit. Describing it in words is sufficient. An iron nail had been pounded flat and then sharpened to a point with two cutting edges. This was then driven into the end grain of a block of wood (pad), which was forced into the bowdrill. This was not a refined tool. I could see that replacing the pads had damaged the opening, probably with a screwdriver. It might have been made at one time to accept better crafted bits and pads. As it was, it served the joiner to drill the holes for bamboo dowels when making round tabletops from boards. At least in this form, this bowdrill is in no way an accurate tool and is very limited to small size holes. It is comparable to putting a finishing nail into a drill chuck. It does a task but in a very limited application.
I want to believe, at least, that at some time, drill bits and pads were made specifically for this tool, either for manufactured bowdrills or to be used in conjunction with homemade versions. I've never seen these tools used on a construction site and I have no idea whether any craftsmen prefer them over the more readily available cordless drills on the market today. It might simply be another example of the conservative impulse in so many aspects of Han Chinese culture. It nevertheless might have some advantages that have yet to be identified.
Short of finding a set of bits for this tool, there exists a possibility that evidence exists in printed form, possibly in advertisements or in tool catalogues. I am still looking for a cooperative scholar with connections in one of the state or university archives.  
If any reader has a suggestion where to pursue this line of inquiry, or wants to add anything to the discussion, please reach me through the comments.

29 December 2014

Waste not

Here are some boxes that I just finished putting a linseed oil finish on:
flip lid front

flip lid rear
 
sliding lid front

sliding lid rear










































And here is the source the wood to make these boxes.
















This unused pallet was just gathering dust when I decide to pull it apart and see what it was made of: rough sawn poplar, but the special discovery was the amount and varieties of sapstain fungus that had infected the planks. On the downside, the wood is very brittle and unforgiving to work, readily splitting and chipping off at the edges. On the upside, it's like a painting from the inside out. I have no idea under what conditions the fungi got into this wood, but it's possible that the varied colors are actually more intense due to competition between the different species setting up zone lines to defend their resources.
Controlled rot, and we see beauty in the patterns of the organic battlefields.