31 March 2014

Number magic

I read the first half of By Hand & Eye,  that's the  George Walker  part, the second half is by Jim Tolpin. I was not too happy with it.  That's the information part of this post,  the rest is sort of a rant.

After some thinking I focused my dislike in three parts - it's sort of a long rant:  American taste.  Whole numbers,  there is no harmony in drawing.  Classical order in columns.

... that was it,  we are a few months later now,  time to create and finish that post.

Whole numbers,  there is no harmony in drawing.
I liked George Walker post about the Golden Rectangle where he exposed that the close relatives of the golden rectangle: 3:5 and 5:8 feel just as right. But as I discovered through the book, for him it is about the exact whole number proportions,  where for me it's about the ballpark of the golden rectangle.  And that's where for me drawing differs from music.  If in music proportions 2:1 (octave) 3:2 (quint, violin tuning) 4:3 (quart, guitar tuning) ... can be very precise,  I don't know if we need or can achieve a similar precision of proportions when just looking.

American taste
Even if we share much in common with USA-Americans,  it's for example difficult to not see the Simpsons every day - even dubbed in French, sometimes there is a difference. The book uses three pictures of a high boy to ilustrate design.  For me it's a good example of weird looking furniture.  It looks as a semainier, a small seven drawer chest.  The square body  is set on overly curved legs,  probably animal legs,  going for a baba yaga style.  With its legs the top drawers stand too high and are inaccessible.
To finish there is a top that makes me think of a French pre-revolutionary hair piece, unsurprisingly as the periods agree.  The whole can be seen as anthropomorphic,  with its legs, waistline, round faced central top drawer and hairpiece. And with anthropomorphism we go Disney style.
To be fair we have here in town also an overdecorated period (17th century) thing,  probably never liked by everyone. Specifically in may 1944 a keen eyed pilot followed tram tracks towards the church and led it's bombers flight into hitting the church (hitting the center preserving the front) and many other things,  missing their target, the large railway station covering a surface of over 40 football fields, 1km east. The google earth picture shows the narrow street and church on the left and a small part of the railway station right.

Classical Order in columns
Classical fronts are uncommon here, classical columns as discussed in the book, are nearly inexistent.  My house is an exception it got a neo-classic redesign and front in 1830+ without columns. But things changed overt time, in 1950 for example the first floor lowered it's ceiling from 4m to 3m, impacting the appearance of windows. So it's not a pure classical form anymore.
As far as I know there is only one example of columns in town,  also dating back to neo-classic tastes of 1830+.  And as the picture shows it is preserved architecture,  as the building has already been recreated a few times and this time only the front was left to stand. But if I measure the size of the building - order depends on size,  I could check if this is the classical order of Vitrivius or Alberti, Serlio, Palladio, Vignola, De l'Orme, ... ,  but then and now a building is more than exact  proportions.

Being me, I am more interested in the origins of the Doric order rather than its standardized proportions. Certainly the functional wood origins of what would become later decorative aspects.

What I do share with the book is a liking of classical sophisms, here I think to have found one:
"Ornament and mouldings must have a function. While we think today of function as primarily a structural element (a way to meet a physical requirement), the craft idea of function was much broader, because the definition of function included visual appearance."

 Next time I hope it will be about a book I do like.  But then maybe I prefer books I don't like.

05 March 2014

System D

Looking at Pierre Ricaud's  Comment construire en bois (1985 for my edition, although most of it looks like 1960), I see only one page dedicated at the construction of a workbench. A French workbench by nature, even if I have seen  different models that are just as French.
The dimensions are mentioned,  more or less 200cm long, by 50cm deep and at least 6cm thick. The possible wood species: oak, hornbeam (is he from the Mulhouse area?), beech. Breadboard reinforcements (2) and (3). That's it,  where the book title states it's about how to build with wood, the rest of the text is about accessories. 
So? The right leg has a shadow,  are the legs not flush?  The joinery? The dimension of the legs? Can I go for archaic Roubo joinery? The height?  How do I fix the breadboards? Can I laminate the top?  ...  
All these questions are for the reader to answer,  they probably fall under System D (système D).  The D stands for démmerde or débrouille.  Démmerde is, I guess, the main action after the shit hits the fan and débrouille is to untangle,  but more specifically: you're on your own,  solve it . Here, up north we rather say tirer son plan (draw or pull your plan)
Système D (systemed.fr) with D from débrouillard is also or is it before all a DIY magazine since 1924.  Although, seeing the umbrella holder on the first cover, it's more likely the D from Dadaism.  Duchamps is it you?

The second holdfast (10) on the picture is interesting,  it's an hinged holdfast with a cammed handle, allowing to unlock and raise the holdfast in one movement.

A second page describes some extra clamping add-ons and two saw sharpening jigs,  one for band- and frame saw blades the other for circular saws; and a Zyliss.

10 February 2014

Hand cranked drill press

Touched by envy after seeing Chris (from Chop With Chris) making a dog sled without power tools, I refocused my envy from his telekinetic abilities to the tools.  So yes, a post drill,  what about that.  Looking on a second hand web site I found one, or rather something close: a hand cranked drill press with closed gear box, unknown to me but the price is probably lower and it's faster (up to 600 rpm).

The first impression is that it has much in common with a standard two-gear closed-gear-box hand drill.  Too much in common, my first reaction was to search how it works, as no separate depth setting is visible. After opening the drill and some trials this is more clear. Surprisingly apart from the extra high speed crank axis, gear by gear the drill is similar to a post drill.  It just lacks two extras: the lateral flywheel and a freely rotating depth setting threading.

So the main difference is that for depth setting the axis is directly threaded and and not through a threaded cap on top of the axis.  The situation is then similar to a bolt and nut where the axis is the bolt and the depth setting wheel a nut.  The moment the drill is cranked, it lowers fast.  When the material is reached and the drill engages, there is a pressure build up on the nut until it starts slipping like nuts do when a bolt is tightened.  When through drilling the pressure lessens, the axis is pushed deeper until the nut fully slips again. To make slipping more easy the nut is set on a ball bearing. And as the nut turns mostly together with the axis it is also build as a flywheel for added comfort.
Some extra fun is that when drilling is done and the crank is stopped, the flywheel will continue turning, pulling the axis back up.  If this is not enough raising the drill can be done by cranking backwards.

There are two bolts at the top of the gear box.  The left one presses through a spring (and a missing part, probably a bearing ball) on the flywheel to increase friction and by this the downward pressure.  The right one needs probably to be filled with grease (it was dry and rusted) to keep everything slippery and wear free. Slightly tightening the screw injects some fresh grease.  I hope that greasing will lessen the friction over time as it is rather high when using second gear,  but that's probably the way it is.
Is it usefull?  With it's automatic pressure control it's maybe too brutal for small diameters on wood.  But as the seller told me it was his favorite tool in his grandfathers workshop fifty years ago.

03 February 2014

Kato and Kawai video

Like many others I have seen the Kato and Kawai video.  The video looks at a usable back iron set between 0.2 and 0.1 mm for shavings of  0.05 and 0.1 mm And if I go directly for the end conclusions:
1. for shavings of 0.05 mm and less there is no tear out even without back iron. 
2. the back-iron must be set proportional to the shaving thickness
3. a steeper back iron angle gives less tearout.

I looked in an earlier post at the Howal Universal Plane, the back iron has a minimal set compared to the Howal values between 1 and 0.3 mm for the back iron setup.  I have also seen descriptions of jack planes favoring a back iron set at 2 mm.  Here the Howal description, that I dated back to the seventies:
1. Schrupphobel  (scrubbing plane):  Use the rounded blade and open the mouth
2. Schlichthobel (jack): Mouth to 2mm
3. Doppelhobel (double iron jack): back iron at 1mm, mouth at 1.5mm
4. Putzhobel (smoother): back iron at 0.5mm, mouth 1mm
5. Reformputzhobel (high angle smoother): back iron at 0.3mm, mouth at 0.5mm and raise the bedding to 49°

What I missed in the Kato and Kawai video was one more test,  they tested on shavings of 0.05 mm and 0.1 mm,  I wanted a test on 0.2 mm shavings.  Just to see how in their setup the ideal distance for a back iron relates to the thickness of a shaving.  But they do mention it in their end conclusion 2. talking of a distance proportional to the thickness.  At first sight Howal also proposes a linear increase with the thickness.  I have read people favoring a nearly static setup as opposed to this linear setup: "1/64 ( 0.4 mm) is at the outer edge of what will actually reduce tearout" I see this as a static setup as Kato and Kawai conclusion 1. sets 1/128 at the inner edge. So setting the back iron close to 1/128 (0.2 mm) would be the only useful position. That idea probably works, but is rather strange as the back iron would protrude under the sole for thicker shavings making it a giant scraper.

I talk about their setup as it misses a mouth. This gives a tightly rolled shaving.  That's different from normal planes where the shaving would come in contact with the mouth that redirects the shaving backwards,  as if confronted with alternating irons. So conclusion 3. is not necessarily the whole story as there are alternatives to a high angle on the back iron to increase the downward pressure on the shaving.  A mouthed plane a well set back iron can give a tell-tale straight shaving.  But any irregularity in this shaving chimney will ask for a lessened back iron position.

My conclusion,  very watchable (... maybe not with the family) video.  And by lack of bevel up planes, more or less setting up a back iron is part of the fun.