Tuesday, April 26, 2016

no need for japanese mambo jambo

Somewhere I read that all the info you need to become a good woodworker was free. I totally agree with that. And I think it's morally reprehensible to put knowledge behind paywalls of any kind. One doesn't have money because one is smart or worked hard. It's mostly related to the special skill of choosing one's own parents. Born white and with money in a first world country sets you on top of a few million people, if not billions. Make it even 20cents dearer for them to know what you know seems like a crime to me. Mostly when you, your parents, and your grandparents have profited of the exploitation of those people be it by slavery, economic dependence or simply by producing far more of your share of pollution to have the life you have and don't give a shit.

So when my friend Gabe speaks in japanese mambo jambo about triangles I go back to my old friend pitagoras and start from there to splay legs. Pitagoras theorem is free, like the concept of wheels and diesel engine. Google's algorithms are not. Neither several life saving medicaments or technologies. Without been boring about the whole story of the concept of copyright, it stems from the same place as capitalism, colonialism and the like: england 1600s. And as every reactionary idea, it attempts to present as natural what was once imposed.

That's why there is a little sign at the end of my blog that says something like all this crap is creative commons. Ya know, it's supposed to help the common good.

So today I used the spare leg for one side, and then made another one for the remaining one.

The first leg is "just" 3mm undersized, well, in fact the mortice is oversized. The others are quite decent. We needed to have dinner tonight so the bench was moved down before I could finish plane it. Once I put shellac on it I show some close ups.

It's much easier than what I feared, and you can solve this with simple geometry and pitagoras theorem. In the case of this 50x50mm legs I needed to cut 3mm from each side to make the diamond shape.

A few tips: cut the bottom of the legs at the end. If you already cut one bottom, you can use it as a paring block. Make a paring block if you haven't cut a leg's bottom. And not only use it for paring but also for holding the chisel at an angle when you hammer it.

 The bench sounds like crazy when we sit. Well, mostly when I sit, it holds julia without complain. The dog sleeps under it. I hope it doesn't break.

Monday, April 25, 2016


Gabe said something about 2 legs being the mirror of the other. I thought, and it made sense to me, that since the mortices where there those go in one way only, so it needs to be so. But in the case without mortises not anymore.

So I went ahead and since I'm skipping the stretchers just marked and cut the 4 legs in the same way.

Now I have two spare legs or a frankestein extension work for tomorrow:

Or maybe our floor is so uneven that it will work anyway. I had anticipated that something was going to go wrong, so I had 1 spare leg. But I never thought it could go so wrong. Well, live and learn. 

It's looking nice —imho — though. Way better than the paint buckets that it used to have as legs. Tomorrow I plan on finishing the mortises and surface planing the top.

Thursday I go buying wood and want to make one or two more. By the 5th mortice I think I will get the hang of it.

Sunday, April 24, 2016


Mara macho. Male mahogany that is. Or so called in Peru or wherever this bastard comes. I have problems sanding Rosewood but I'm getting allergy planing this boy. Real annoying wood and the grain is a bastard.

This week I'm going to get more spanish cedar, which actually comes from Bolivia and not Spain.

The legs, as you can see are diagonalised. Since the dog sleeps under the bench where these girls go I won't put stretchers to it, so it's a mix of staked and japanese bench. With spanish cedar on top. I may re make the legs one day since I'm not so happy with the grain of these one.

My little bevel gauge is no the best for marking out, you want something long so you can transfer the slope from the sashigane to the gauge easily. I want one like this: http://granitemountainwoodcraft.com/2016/04/10/splay-leg-layout/

You see Gabe, I took the challenge.

Wednesday, April 20, 2016

not so square anymore

Managed another 30min or so at the milling Maschine today and what was square before, it is not so now.

 The same spiral cutter was used to cut the profiles, then I skimmed 2mm from each side, also from the wood.

And later went to "Pernos Irrua" to buy the studs. It's not only lighter but the relief lets you put your index finger there and it's way easier to hold.

We are still thinking how to broach the hole square, but seems like files will have to do, there are no small enough cutting tools in the workshop to shave it. For the knife I'm debating whether to cut one of the japanese nickers I have but maybe a cheaper iron will work too. Who knows.

Also and before I forget, when you have spirit varnish, you also need a lid for the container, so it doesn't dry:

for not being airtight it last surprisingly long. This is another of Opa's secret that I haven't seen online.

after 20 years of use that mug will start to look cool.

Monday, April 18, 2016


Don't look at the plane. Look at the reflection of it on the wood.

there is a thicker part at the edge that I couldn't clean with my rag and alcohol. I guess it's still drying.

 It kinda reflects light, has a lovely texture, and it's handmade in valpo.

Die Rezepte comes aus Deutschland

grind everything very small. It's important to have a marking gauge to measure the portions of each ingredient. I think it's measured by weight but opa was not explicit on this.

Sandarac and benzoin go to powder real fast. Shellac no so.

Then leave in a bottle for some time. I left it 3 days but I have the impression 1 week would have been better. I think the benzoin didn't dissolve properly and that's why I have this thick coating on one part, I grabbed a lot of it at once.

Will make more and put it on some lenga, so you can appreciate better the lovely red colour of benzoin on a white wood for background.

Applied with a cheap brush (bad idea, hairs all over the place) then an expensive art brush (good idea) and finally polished with a piece of underwear with alcohol and camellia oil. To finish, some hand salve from Burt's bees and more underwear. It smells like the virgins jihadist martyrs are promised before blowing up. Real sweet.

Friday, April 15, 2016

A bit too square

Next tool needed to make a violin: purfling cutter. 

I tried it with a japanese double knife I've got but the blade is too large, so I was tempted to make some smaller and brassier. The model may ressemble somehow a certain Ibex purfling cutter out there. The handle is lenga.

 Started from square stock of brass from the university workshop and after some 50min of milling I was here:

Do you see that chip on the bottom? I was cutting "against the grain" on the milling machine and the whole thing just kinda exploded. That is, I was feeding it backwards if you know what I mean. 

The handle is lenga, the holes are threaded for M5 threads and I need to file that hole square so the blades will go there fixed between the screws. 

However, it's a bit too square at the moment, gonna take it to mill again next week and shave some 2mm from each side. 

Another important piece is the mould. Fecit 2016 on real wood. 

Why one would like to time-stamp the moulds? I guess to see how they move, and how your designs evolve on time. Or to know how long they last... anyway, it looks cool and had to visit my friend Alfred Dürer for some advice on the fonts. 

Next step is to drill the mould to accept the "clamps", wooden sticks that will hold the corner blocks with string or rubber bands. On the meantime still looking for suitable chilean wood for the top. 

Friday, April 8, 2016

The making of a violin maker

A bit of an update involving material goods and no electrons and logic gates. 

Wednesday grabbed some aluminium from the workshop and asked the technician to fix the new bearings I got for my bandsaw. Somehow the ID is in inches but the OD is in mm. That means factory bearings don't fit and I need to grind them to size. However, the bandsaw got new blade and orange tires, and it's finally cutting straight and smooth. What a difference it makes. There is some resonance on the vertical normal mode when I cut though,  the hole thing tends to move up and down like 1mm when I'm cutting wood at a certain speed. Any ideas how to fix that? 

Well, with the bandsaw working properly I can cut the mould for the violin we are planning on making with Nico. He's been learning how to draw violins with dividers and that's what we did on the metal plate:

I don't have a fret saw, so most of the time we spend it with the file. If somebody wants to make me a present a knew concepts would be appreciated here.

 After lots and lots of filing with the coarsest one I've got, we tried to leave everything 2mm oversized. It started to look like a violin.

 It may need some more care on the edge but it lives on the workshop already.

 Close up of the corners so you can check how precise you can work by file alone. Well, and some dowelled sandpaper.

 As you get closer and closer to the line, it takes more and more time to do a proper job

 here still need some 20 min of work.

I thought it was going to be much more difficult and time consuming, but you can finish this in an afternoon. A set of different size curved files would be handy too. 

With this mould, I will transfer the size to the wooden piece that you see on the background (bolivian cedar) and cut it. We are going for metal templates, wooden moulds, and no clamps for the glue up.  Thicknesser a la Stradivari and local woods for the body. Repeat in spirit what the old guys did. Oh, if you are sending me the fret saw as present, can you add some animal glue to the package? I cannot find in Chile and my marriage is too fragile to start cooking hide in the house. Patience has a limit too. 

I want to make another one on brass now. 

Hopefully with this new tag I can keep track of all the side projects necessary to make a violin. As you can guess by now, I'm not so interested in how to make a violin but in how to make a workshop that makes violin makers. That's what this is about. Let's see if tomorrow the mould is done. 

Monday, April 4, 2016

why japanese planes are better

I'm pretty sure japanese carpenters had access to finite element analysis computer. Some alien shit or so.

Fast course on elasticity: materials are elastic. That means they deform when pressure is applied to them. Pressure is force per unit of area, so the smaller the area of application, the larger the pressure.

Japanese planes compress more the wood they are planning by having only two points of contact with the wood.

Stanley planes on the other hand are flat, so the force is divide on a larger surface and the respective deformation is smaller.

What has to do this with the cutting ability? Easy, the answer is stanley 60 1/2.

By compressing the wood on front of the cutting edge, you are effectively lowering the angle of the blade.

How much is this deformation in a real piece of wood? To my physicist approximation, something between 1 and 10 microns for a Young modulus of 11GPa.


Now you can tell your wife you need one plane for every kind of wood and every thickness you want to plane. The consequence of this is that depending on the stiffness of the material and its size your optimal sole configuration will vary.

And if you are waiting for the post why japanese chisels are better, I tell you right now: they are more beautiful, which according to Plato is the same as more truth and better. Go figure.

EDIT: as per Jason's request varying the size of the flat on front of the mouth: