Category Archives: Miscellaneous

Wheat Corn Bread – an easy recipe

Breads are mostly made from wheat and rye flour. This is at least a common misconception of the westerner, living in the Northern hemisphere. Almost all kinds of grain can be used to prepare bread, albeit, bread of different shape, depending on structure of the flour, and the rising agent used.

Here, a simple recipe that uses a combination of wheat and corn flour, with yeast as the rising agent.

corn flour

In a big bowl, mix:

1000 g of unbleached wheat flour
600 g of corn flour (masa type, nixtamalized)
30 g of salt (measure rather accurately)
1 bag of active dry yeast

To the mixed powders:
80 g sunflower oil, or pumpkin seed oil
1450 g of water

Corn flour absorbs a fair bit of water, you might need to add up to ~150 g more, depending on the type.

Mix properly, best done using hands rather than a big machine.

Let rise for about 1.5 hours, until you see a considerably increased size.

Portion into about 16 to 20 parts, twist them a bit and put on non-stick paper, on a baking tray.

ready for oven

Bake at about 400-450 F, 200-230 C, for about 22-25 minutes. Oven needs to be properly pre-heated. If at all possible, add 1-2 cups of water on a lower tray, to generate steam during the first part of the baking time.

fresh bread

Mmmmhhh! Very delicious!

One variation – mix 1/2 package of yeast, 500 g of the wheat flour, and 500 g of water – the day before the baking, and let sit overnight, at moderately warm temperature (about 70 F, 20 C). For baking, just add the remaining quantities of the ingredients as per the list above. This will give more coarse pores, and adds a particular refined taste.

LinuxCNC EMC2 HAL Files: 3 axis mill, 2 axis lathe with encoders, jog wheel, axis compensation, camera view

Due to frequent requests – here are the configuration files for my LinuxCNC (EMC2) controlled mill and lathe.

The mill is a 3-axis machine, with stepper motors and jog wheel (see earlier post).

emc2 linuxcnc fkm 3 axis mill hal with jog 150101

The lathe has 2 axis, stepper motors, and digital readouts. No feedback on the readouts, but they are great for highest precision work. Configuration files also include the setup for spindel-synchronized movement and spindle speed readout. I have run spindle-synchronized toolpaths for cutting regular and tapered threads with no issues at all, up to a few 100 RPM. The GUI (axis) is also configured for use with a little camera that is very handy to set the coordinates of the tools.

emc2 linuxcnc jet lathe with optical scale and spindel index 150101

Any questions, please ask. These files are meant as a source code collection for you to code your own HAL files, etc.; if you need help with a particular configuration, feel free to contact me.

Please consider that some fragments of the code might be copyrighted by others – however, I have modified it so many times that it is virtually impossible to trace back.
My contribution to these HAL files: You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission. The work may not be free of known copyright restrictions in all jurisdictions. Persons may have other rights in or related to the work, such as patent or trademark rights, and others may have rights in how the work is used. I make no warranties about the work, and disclaim liability for all uses of the work, to the fullest extent permitted by applicable law.

Homemade Hard Candy: sugar free extra-strong eucalypt-menthol

In winter time, nothing better than some low-calorie, strongly flavored candy. It works against germs, improves general health and well-being, and preparing such candy yourself is fun, and you can make them ‘extra-strong’.

That’s how it works. First, you need to get some isomalt. Isomalt is a sugar alcohol – much less (about half) of the calories than regular sugar, it doesn’t attack your teeth, and is slowly metabolized by the human body (doesn’t lead to spikes of you blood sugar level). It is sweet, but not quite as sweet as sugar. No metallic after-taste, it is purely sweet. And, it is non-hygroscopic (it will not absorb water when stored), resulting in less sticky mess, and eliminating the need to wrap each and every candy separately.
This makes isomalt a nearly ideal ‘carrier substance’ for any flavor.

candy isomalt

Take about 150-200 g of isomalt, and melt in a small cooking pot. Ideally, use an electric stove – don’t overheat! Stirr!

candy melting isomalt

Once everything is molten, pour onto a silicon baking pad, or siliconized/non-stick (lightly oiled – vegetable oil) paper.

candy sf molten isomalt

Watch out! This is dangerously hot stuff – it can cause severe burns! Keep children away! I always wear a pair of cotton gloves for isolation, and a pair of rubber gloves on top.

Now, the tricky part. Using a metal blade, knife, or similar tool, move the molten isomalt around, outside in, until it is cooling down a bit, and getting more viscous. This requires some practice.

Next, most important step – addition of the flavor.

candy eucalyptus oil

candy menthol

The flavor – a saturated solution of (-)-Menthol in Eucalyptus oil (this is about a 1:1 ratio). This is best done directly in a pipet bottle, very handy for easy dosing. The active ingredient of Eucalyptus oil, 1,8-Cineol is a really great compound, it kills bacteria of all sorts, and constitutes about 80-85% of the oil.

Menthol –

1,8-Cineol –

The right time to add the flavoring is reached when the viscosity is just about high enough to handle the molten isomalt with your hands (make sure to thoroughly lubricate the gloves with neutral-taste vegetable oil).

The flavoring is put directly on the semi-liquid isomalt, and folded in from the perimeter, to the inside of the melt.

candy folding and pulling

Then, take the candy in your hands, and pull it, fold it, pull it, until it is cool enough to be portioned into candy pieces. Can be a bit hot, but never mind. Once the right temperature/viscosity is reached, timing is everything! Now things have to happen quickly!

Using a strong pair of scissors, with some vegetable oil applied, cut the candy into pieces of adequate size. Rush!

candy cutting

Best use some non-stick paper, and let the candies cool down.

The final step – put them into some nice metal containers for storage. I never store too many in a single container, because they will lose favor more quickly, with a large container being opened all the time to take out a few candies only.

The result of a single batch – you can handle up to 250 g of isomalt in one batch with some practice.

candy sf final

Braided Bread: German “Hefezopf”

One of the staple foods, at least in the southern part of Germany: Hefezopf – a type of braided bread made with yeast (rather than baking powder), which is sweet but not too sweet – still goes well with eggs, pickles, smoked meet, just give it a try!

To prepare, follow these instructions:

(1) Let 1 kg of wheet flour (general purpose non-bleached flour is prefered), 2 eggs, 125 g of butter warm up to room temperature. If there is no time to let the butter warm up – just cut into small pieces and add to the heated milk later.

(2) Take the 1 kg of flour and put into a large plastic bowl. Using a spoon, make a little hole and add 25 g of yeast (half a standard cube of fresh yeast; add 1 tablespoon of sugar). Alternatively, thoroughly mix with 1 bag of active dry yeast. No need to add too much yeast!

(3) Take 480 mL (about 480 g) of milk and heat to a warm temperature. It should be warm to hot, not just lukewarm.

(4) If fresh yeast is used, add some of the milk, like half a cup, to the yeast and stirr to form a semi-liquid starter; cover with some flour and let sit for 15 minutes to activate the yeast. Skip this step if active dry yeast is used.

(5) Add 125 g of butter, 160 g of sugar, 1/4 tablespoon of salt, 2 eggs and the remaining milk to the bowl. Mix thoroughly, knead for for a few minutes; best done by hand. Add a bit of milk (or warm water) if dough is too stiff. Dough should be rather soft.

(6) Cover with a towel and let rise for about 60 minutes. Avoid air drafts – keep at a warm place. Dough should rise to about double its size.

(7) Knead properly, add a bit of flour if needed.

(8) Split into 4 equal sized strands, and form braided bread.

(9) Pre-heat oven to 165°C, circulating hot air type oven; 180°C, regular oven.

(10) Let braided bread rise for about 15-20 minutes. If golden crust is preferred, cover with a mixture of egg yolk and water (1:1).

(11) Bake for about 30-35 minutes.

(12) Let cool. Don’t cut while still hot!

Not the most beautiful braiding, but, delicious:

Note: this type of braided bread is ideally suited for freezing – just put in plastic bag. For best taste, don’t store for more than 6 months.

FKM349VL Benchtop Mill: control, EMC2 LinuxCNC interface

The FKM349VL is one of many similar benchtop mills, Made in China. It’s size and power requirements make it quite suitable if you need a small machine that is still capable of machining aluminum alloy, and to some degree, even steel.

General characteristics – X travel = 490 mm, Y travel = 160 mm, Z travel = about 330 mm.
Table size is 700×180 mm

Spindle is MK3 with M12 draw-bar (this is the most significant limitation – only manual tool change!).

fkm349vl mill

The linear stages use 16 mm, 4 mm pitch ball screws. Motors are 4.5 Nm, 6 Amp nominal. These are quite powerful, plenty of torque for this machine. This allows velocities of about 1800-2200 mm/min with no steps lost.

The control electronics are all housed in a cabinet attached to the machine. All pretty nicely made (motors powered by roughly 50 VDC, from the toroidal transformer; the blue transformer provides 12 VDC for the control circuits):

fkm349vl control overview

The stepper drivers – Leadshine units, up to about 5.5 Amps, configured for 4.3 Amp peak, 3.1 Amp RMS. Type MD556, V2.5. The units are similar to the Leadshine M542 and M752 units. Aka, KL-5056, aka, Rhino RMCS-1102 – many similar units exist.
The stepper motors have 200 steps/rev; the drivers are configured for 8 microsteps per full step – this results in 1600 steps per rev.

fkm349vl stepper driver

By default, this machine came with a “CNC-Workbench” CNC controller, offered by W+W Automatisierung ( I gave it a try but soon found out that it is not up to my requirements; it’s a nice little controller, for what it is, no complaints, but really only for very basic uses, and difficult to interface with other CAD/CAM software. Most of my other machinery either uses industrial control, or EMC2 (LinuxCNC), so the decision was soon made to adapt the control to EMC2.

EMC2 has a powerful hardware layer, using the parallel port for control input and output. To allow proper speed and noise immunity (very important if you don’t want to run into issues!), a little interface circuit was fabricated, on a piece of perf board:

fkm349vl interface brd

fkm349vl interface brd solder

fkm349vl control schematic

Nothing too fancy – low pass filter, Schmitt trigger, LED driver (the stepper driver use optocoupler inputs). The limit switches are combined by diode OR connections, switches are normally closed – to prevent machine damage in case of a broken wire.

The internal interface of the machine, originally used by the “CNC-workbench” controller uses a pretty uncommon high density D-SUB connector – 44 pins!

fkm349vl high density plug

First time I have seen this type of connector, but it offers a fair number of contacts, for a pretty reasonable price, and quite a bit of soldering effort!

The software implementation – let me know in case you need the EMC2 HAL files for reference. Also attached a little incremental encoder as a “handwheel”, using a second parallel port. Quite amazing what you can do with a second hand computer, a few parts, and free software!

German Bakery: sourdough bread, ‘quark’ variety

Living in the US, I don’t want to miss good home-style bread. Sure, all kinds of bread are available here, but at a price, and you never really know what is inside.

This bread is about 60% rye, 40% wheet. Rye flour always requires the use of sourdough, and we have to consider two cases:

(1) You are the proud owner of some sourdough, or have a friend that has some.

(2) No sourdough at hand. Don’t worry. Sourdoug can be prepared, without any starters, at home.

(a) mix 50 g of dark or semi-dark rye flour with 50 g of water; stirr; leave at room temperature for 24 hours.
(b) add 100 g of dark or semi-dark rye flour and 100 g of water; stirr; leave at room temperature for 24 hours.
(c) add 100 g of dark or semi-dark rye flour and 100 g of water; stirr; leave at room temperature for 24 hours.
(d) add 100 g of dark or semi-dark rye flour and 100 g of water; stirr; leave at room temperature for 24 hours.
At this point, you should have quite a bit of sourdough ready, with small bubbles, and with no mold.

Some key items:
(1) Use boiled or otherwise chlorine-free water; tap water is perfectly fine but boil and let cool before use to remove any chlorination
(2) Use very clean utensils; store at a clean place – away from any sources of mold.
(3) Use a plain plastic or porcellain dish; don’t cover it; don’t use a metal dish.
(4) Temperature is fairly important – not too hot, not too cold.

For later use, best put some sourdough (~100 g) into the freezer.

Now, as you have sourdough now, let’s get started.

Step (1) – Take 100 g of sourdough, add 200 g of rye flour, and 200 g of water; leave at room temperature for 24 hours.

Step (2) – Add 400 g of rye flour, 500 g of water. Leave at room temperature for 24 hours.

Step (3) – Add 750 g wheet flour, 200 g of (warm) water, 30 g of salt (measure accurately!, mix in with the flour), 1 cube of yeast (available mainly in Europe – 42 g each; can be substituted by one package of active dry yeast), 500 g of ‘quark’ = curd cheese – low fat type.

Step (4) Knead properly, using your hands or strong machine; cover the dough with a towel, let the dough sit for about 1 to 1-1/2 hour to rise.

Step (5) Form any shape and size of bread. I prefer multiple small pieces. Use some wheet flour – the dough is fairly sticky.

Step (6) Let rise for about 30 minutes; preheat oven to 220-230°C.

Step (7) Bake. After 10 minutes. Reduce temperature to 170-180°C (depending on oven; I use a forced convection type: 170°C). Bake for another 45-60 minutes, depending on size of loaf. If you prefer a shiny crust brush with water (with a bit of corn starch added) immediately after removing from oven.

Step (8) Let cool. Don’t cut off pieces for at least 1 hours – other wise, steam will escape.


Note – rye flour refers to semi-dark rye flour (not whole grain). In Germany, known as Type 1150. Wheat flour – best use any ‘bread flour’, in Germany, known as Type 1050. I use Type 405 because it is commonly available and it is amazingly cheap (currently EUR 0.32 per kg!!).

bread full

bread cut

Xmas Bakery: Nougat Plätzchen(=small cookies)

These are one of my favorite Christmas “Plätzchen”(=small cookies). A kind of nougat shortbread, covered with chocolate.
First, prepare a dough by thoroughy mixing/kneading (no machine needed, best use your hands):

250 g nougat (soften in microwave)

80 g butter (soft)

60 g sugar

300 g plain flour, German Type 405

1/2 teespoon baking poweder (throughly mix with flour)

a little bit of salt

1 egg

some vanillin powder (or vanilla essence)

Once properly mixed, make two rolls, and wrap in some plastic foil:

Let rest for several hours in the fridge, or overnight.

Then, form nice cookies, either manually, or by rolling it to about 3/16″-1/4″ thickness. Don’t roll too thin!

nougat ausstechen

nougat ready for oven

Bake in oven at medium temperature. For best result, use 165°C circulating air. Baking time is 10-12 minutes.

Let the cookies cool to room temperature. Eventually, your efforts will result in a pile of cookies ready to be chocolate-coated.
nougat baked

Then, melt

200 g baking chocolate

150 g of really dark chocolate

using a water bath (also to keep the chocolate warm during the coating process).

nougat chocolate application

For guests that are worried about too much chocolate, it always is a good idea to leave some of the cookies partially covered.

nougat final steps

Use non-stick paper, and let the cholocate solidify for at least 18 hours before packaging.
Store in odor-free, dry place. For best taste, let them rest for at least a few days.

Xmas Bakery: Christstollen

The time is right to get started with some Christmas bakery. Stollen, a long standing German Christmas tradition. It comes in various kinds and modifications, but there is only one truely original recipe.
Don’t use any self-rising flour, or baking powder – really Stollen always uses yeast to rise.

1 kg plain wheat flour, Type 405 according to German industrial norm (DIN) no. 10355

60 g of baking yeast (about 1.5 regular yeast cubes), can be subsituted by active dry yeast, but the real thing is always baked with fresh yeast, commonly available at all German supermarkets.

250 mL milk (warm up; not too hot!)

First, to get the yeast started, put all flour in a suitable bowl (plastic bowl most prefered), make a hole in the center, put in the yeast and mix with some milk to form a semi-liquid dough. Cover with some of the flour, and let it sit for 30 minutes.

stollen yeast

This is how it should look like.

1 egg, 1 egg yolk (some traditional recipes don’t use eggs, but I highly recommend it, otherwise, it will be a pretty ‘flat’ Stollen, unless you have a suitable mould)

180 g sugar (extra pure saccharose – just kidding; refilled with ordinary, plain sugar)
stollen extra pure saccharose

200 g butter (room temperature!)

and, the remaining part of the milk.

My traditional recipe doesn’t need any almonds – but these are common additions to other Stollens. Therefore, you might add 125 g of ground sweet almonds, and 50 g of ground bitter almonds, along with some more milk.
Also, you can add mace spice, but not too much!

Knead to a firm dough. If too dry, add some more milk. Don’t add too much, dough should not be sticky or too soft! Properly knead with your hands. No machines are required for this recipe.
Let this dough raise for at least 60 minutes at a warm place.

In the meantime, we prepare the additions:
200 g citronat (rather finely cut!) – candied peal of a special type of lemon
100 g orangeat (finely cut!) – candied orange peal
500 g raisins (wash throughly with at least 1 liter of boiling water, and pick out any that don’t look 100% perfect)

stollen ingredients

Key thing is that the citronat and orangeat are finely cut, nothing is worse than big chunks of this in the final Stollen.

Once the dough has rested long enough, the citronat, orangeat and raisins are added – best by flattening out the dough to about 3/4″ thickness, additing the ingredients, and then folding the dough – this will reduce the effort to form a uniform dough.

Finally, form a Stollen:
stollen ready for oven

Make sure to remove any raisins from the surface (these will scorch and give bitter taste) – just push them in, or remove and eat.

Let the Stollen raise for about 30-45 minutes (avoid air drafts, keep in well-heated room).

Then, bake in a pre-heated oven. Temperature: For best result, an electric baking oven is much prefered, circulating air type. Pre-heat to 200°C.
Insert the Stollen. This will help with retaining the shape.
After 10 minutes, set temperature to 165°C, and bake for another 60 minutes (cover with a piece of aluminum foil after 30 minutes).
Test with a wooden stick – if no dough adheres, everything went fine. Otherwise, leave for another 10-15 minutes.

stollen baked

While still hot, apply about 200 g of molten butter with a soft brush.
Cover with a layer of powdered sugar (prefereably, use pure powdered sugar without any other ingredients that are commonly use in ‘icing sugar’).
Carefully wrap in aluminum foil to provide a good seal.

stollen ready for storage

Now, the most difficult part, let it rest for about 4 weeks at a reasonably cool and dry place (guest bedroom, corridor, or similar place that is free of strong odors and free of damp).

Note: this recipe is all in metric units, rather than cups, ounces, etc, because this is about exact replication of a traditional Stollen. This will only work if done accurately, with precise weights, and well-controlled temperatures all throughout the process.

Dell PowerEdge SC1425, 2x Seagate 3 TB NAS S3000VN000, Ubuntu 14.04.1 LTS: server upgrade

Over the years, a number of manuals and datasheets have been accumulating, also because of my inclination to keep a copy of more or less every document I have used for repair jobs, etc. – sometimes servers go down, and the files disappear in the vastness of the internet.

For some years, I have been dealing with USB drives and NAS storage devices, to keep local copies, and to keep files accessible, but this has become troublesome with space running out, and multiple copies, on multiple drives. Time for a better solution.

(1) A Dell PowerEdge SC1425: 64-bit dual Xeon 2.8 GHz processors, 2 GB RAM. Available surplus, essentially, for the cost of shipment.

poweredge sc1425

(2) 2 pcs Seagate 3 TB drives S3000VN000, these are NAS-optimized drives – essentially, the same hardware as common desktop drives, but targeted for 24/7 operation, with specifications that correspond to long-lifetime “medium”-performance requirements. Performance – this is a private fileserver, and reading rates of 20-40 MB per second are plenty, you don’t need any 10K/15K drives to achieve this.
The drives are operated in RAID1, full redundant.

seagate st3000vn000

(3) Ubuntu 14.04.1 – server. This is a common solution that can provide both Samba (Windows shared folder) and web (Apache) server functionality, at no cost.
Also, it provides the RAID1 functionality (software raid).

Putting these things together, not a big deal – one should think. It took quite some hours to figure out all the settings to get the RAID1 working, and all the files transfered from the old harddrive (~150 GB, the essentials).

Another item to consider, the noise. The SC1425 will be put in the attic, so there is no issue, but don’t consider having this machine anywhere close to where humans reside – it is noisy. 4 fans, cooling the dual CPU, right in the middle of the case (red frame).

poweredge sc1425 2

Some performance stats:

raid1 performance read

raid1 performance write

Roughly 100 MByte/s read/write on the RAID1 pair – perfectly fine to support a 1 GBit/s network speed. Over Samba, I get about 25 MByte/s.
Maybe you noticed the name of the machine – arctur – wondering what it is? – a star, quite a bit bigger than our sun, and not too far away – just about 11 parsec, or 37 light-years! Glad that data server is just a few nano-seconds away, at least, counting the light path.