Restoring an old, broken PacoJet 1

One of the pieces of equipment very high up on my bucket list was a PajoJet. It had stood there for years but the buying price, even for a used unit was just too prohibitive.
A new PacoJet will set you back over 4.500 Euro, even a used one is around 2.000 Euro, which is just a little steep for a private household.

For those who haven’t heard of it, a PacoJet is something like the holy grail for Michelin-star chefs to achieve perfect textures for Mousses, Ice Creams, sauces, etc.
So, when I was offered a broken unit that was deemed beyond salvage at a very low price, I thought “challenge accepted” and bought it.
Unfortunately, there aren’t any repair-manuals available. Also PacoJet won’t sell spare parts, so you have to go with what you can salvage. If one of the specific components like the mainboard or the power supply can’t be repaired, you’re stuck.
I do understand their point here though. The unit is rather complicated, computer controlled and involves high-speed components. Nothing you want your fingers caught in.
If you don’t know exactly what you’e doing, you’ll either get electrocuted or you’ll amputate a few fingers in the revolving mechanics.
This is definitely a case of “don’t do this at home”!
Having restored a few cars, I thought “well, it can’t be more complicated than that”. Unfortunately, it was.

Spoiler alert: In the end I managed and I learned a lot in the process but if I calculate all the hours I put into the restoration, this is probably the world’s most expensive PacoJet ever.

When the PacoJet arrived in the original carton and I unpacked it, I immediately understood why it was sold as broken and beyond salvage.
It was dented and scratched plus it was just dead, one light came on when I powered it up but nothing else.

The PacoJet as it looked when I unpacked it. Dented, scratched and lifeless.

So, in order to get to the ground of things, I opened the case and checked the mechanics.
I decided to take a step-by-step approach and to fix one issue after the other.
Opening it, I immediately saw that the unit was absolutely dirty and grimy.
A sticky layer of fat and dirt covered everything inside the unit.
Over 20 years in a restaurant-kitchen take their toll.

The inside of the device. Very dirty and grimy. Notice also the power-switch. This was broken and water could run inside the power-supply. A major safety issue and an accident waiting to happen.

One of the first things I noticed was that the security-switches for the beaker-holder were totally dirty and worn.
These switches ensure that the unit will only power up when a beaker-holder has been inserted properly. Otherwise only the green power light will come on but nothing else will happen.
This was exactly the behaviour the device showed, so I used an Ohm-Meter to check the switches and found one to be faulty.
I then bridged this switch to test if the unit would power up.

The faulty safety-switch with a bridge for testing if this was the cause if the error. Never run the system like this though!

Powering up the unit, the display came on immedately, the “ready”-light was green.
Before going on, I replaced both switches with new ones. Even though one was still ok, it was just a question of time when it would break as well. It’s always better to replace this kind of thing when the unit is open anyway.

The old safety-switches were replaced with brand new ones.

With the new switches in place I then tried to do a function-test of the device.
Unfortunately, it only sprang to life for a split second before going dark again.
Not what you want, but hey, that would have been too eas and nothing better than a good challenge.
I decided to continue my troubleshooting activities by checking the electronics.
All ciruit boards were extremely dirty and impossible to check.

A very, very dirty and sticky Circuit Board

Even with all the dirt on the boards, you could still see that some components were clearly faulty.
If you take a close look at the Siemens-component in the foreground on the picture below, you’ll notice that some of the legs are askew and seem to have been re-soldered after having broken off at some point.
Clearly, whoever had been tring to repair this unit in the past didn’t have a clue what the were doing.

The Siemens TLE4260 in the foreground: The legs were badly soldered on after having broken off and clearl didn’t have a proper contact.

I decided to bathe the circuit boards in alcohol to clean them. Even though this may not sound like a good idea, it actually works. After having bathed the mainboard in alcohol and having carefully removed the dirt with an old toothpaste, it actually looked like new.

Bathing the mainboard in alcohol actually made it look like new.

When I turned the mainboard over to check the rear, some components actually fell out.
These seem to have come loose at some point and were only held by the sticky fat and dirt that had crept everywhere.
The bent transistors on the picture below also caused issues and needed to be replaced.

After cleaning the mainboard, a transistor plus some other components just fell out. They had been held in place only by the dirt on the mainboard.

I decided to do a thorough check of the board to see if there were any other cold soldering points. I found a few.

The rear of the mainboard. The soldering points marked red were cold, i.e. the components werent’s soldered in properly, causing the unit to malfunction.

I decided to replace all components that looked slightly dodgy, especially the Siemens TLE 4260. I found a source that sells this component for less that 4 Euros, so I bought a handfull, in case I break one or it fails some time in the future.
The comparison between new and old is stunning.

The new TLE 4260 versus the old one. 4 missing legs that lost contact whenever the unit moved. No wonder it failed.

I also removed and tested all other transistors on the board. Checking them in a tester showed some of these to be faulty as well.

Removing, checking and replacing all transistors on the mainboard.

Having throroughly checked the electronics one more time I reassembled the unit and again tried to run it.
This time it actually ran, at least for a while.
Something was still wrong though.
Even though the control panel showed that the rotating rod inside the device, to which the blade is fastened, was supposed to move up again after having finished scraping the frozen contents of a beaker, it continued going down at a very low rate.
This pointed to a mechanical issue, so I needed to figure out the principle on which the device actually works.
Originally I thought this was something like a power drill, very simple and easy to understand. The more I learned though, the more I was impressed by the ingenuity of the machine.
Basically, the whole principle is based on the fact that the rod rotates inside an also rotating steel tube. The rod will always rotate in the same direction and at a constant speed of 2,000rpm while the speed of the tube will vary, depending on whether the rod is supposed to go up or down.
Whether it goes up or down and at which speed depends solely on the difference beween the speed of rod and tube.
If the tube rotates faster than the rod, the rod will move up.
If the tube rotates slower than the rod, the rod will move down.
While the rod rotates at a constand speed, the speed of the tube is controlled by a gearbox which contains two electromechanical clutches, one at the top and the other at the bottom.
Having determined that a mechanical issue was be the cause of this problem, I decided to test the gearbox by powering the clutches separately and to see if they engaged properly.
I quickly noticed that, even though both clutches made a loudly audible click when activated, the bottom clutch didn’t actually engage properly.
The top one seemed to move, at least a bit, but I wasn’t sure if it was ok, so I decided to disassemble the gearbox.

The gearbox. On the left and on the right, you can see the two electromechanical clutches

As can be seen in the picture, the gearbox -like everything else inside the unit- was extremely dirty. I therefore decided to clean all components thoroughly.
Especially the clutch on the left seems to have had contact with a liquid which definitely also ran inside the clutch.
Removing the clutches revealed even more dirt in and around them.

One of the two clutches. My hands were actually clean before I removed the parts. These clutches were extremely dirty.

As dirt is never a good thing inside a clutch, I checked if I could find spares online.
I actually found some used ones on eBay. These looked worse than mine though and were still supposed to cost 100 Euro each. As that wasn’t an option, I took the risk, disassembled my old ones, cleaned them until the inside looked like new and then reassembled them. Miraculously, no parts were left over.
Having cleaned and reassembled the gearbox I again tried actuating the clutches. This time they moved significantly stronger than before.

The disassembled gearbox with the equally disassembled top clutch.

I did actually manage to get the whole unit reassembled, redid the cabling of the mainboard, the top board, the power supply and all the sensors in the unit.
I also replaced the power switch to make the unit properly waterproof again.

Now the big moment: Trying if it works.
Power On, select 1 portion, hit “Start”.
Lots of noise, the rod goes down, stops briefly…. and goes up again!

Challenge mastered, goal achieved. The unit that had been declared beyond salvage actually worked.
Now… taking into consideration the dozens and dozens of hours I spent repairing it, even at minimum wage this repair would have been extremely expensive, so I guess it really was beyond salvage if you take into account the labour-costs.
On the other hand, I did this in my spare time, so in the end I got a fully functioning PacoJet for a low three-digit figure.

Now that it worked, I also wanted it to look nice and fit into the kitchen, so I decided to work on the metal case.
First of all, I removed the dents and sanded it down to also get rid of all the scratches.

The outer case after having filled in the dents and having sanded out the scratches.

I then sprayed it in a classic beige tone to give it the retro-look I wanted.
This way it will fit in with my other kitchen appliances.

The case with the first layer of beige paint.

The beige paint was then covered with two layers of high-gloss clear paint.
Finally, I used chrome-letters normally used in the Automotive Industry to put some finishing touches to that retro-look.

Adding a new Overlay for the display as well as chrome letters to the front gave the 25 year old PacoJet a classic look.

With all the work I put into it, the PacoJet now looks brand new and matches the other appliances nicely.

The “new” PacoJet among the other appliances in the kitchen.

Bosch SmartGrow

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SmartGrow is a smart indoor garden from Bosch.
Originally this was developed as a Kickstarter-project by a company called Plantui who also market it under its original name “Smart Garden”.
The seeds sold by Bosch are also from Plantui, even if they are marketed under the Bosch-brand.
The system comes with space for either three or six plants.
The light will shine for 16 hours and will then be turned off for eight hours.
You can program the time when it switches off simply by laying your hand on the top of the lid.
It’s also possible to put it in “holiday-mode” where plants will grow slower and consume less water.
Sensors feel when water is needed and pump fresh water from the reservior to the section where the roots are located.

Designwise it looks a little like an electric salad bowl. It comes with the bowl, an insert , the lid with the LEDs as well as two height modules.

I purchased the version for six plants. I found the small version to be too small for my requirements and the large version wasn’t that much more expensive.
In addition, I got some extra Height-Modules, a Blooming Light Module plus a Boosting Light Module.
Finally, I bought different seeds and packs to use with my own seeds.

To start up, after unpacking the system, you fill it with 3l of water and 6g of nutrient.
Then the plants are added.
There are six spaces for the plants plus an additional space to top up the water.

The lid contains the growth-LEDs. There is one red, yellow and green LED above each plant.
The blue spectrum is supposed to support the growth of the plant. As long as no height-module is inserted, the light will be mainly in the blue-violet spectrum.
After the first height-mdule has been mounted, all LEDs will go on.

The plants come in packs of three. In addition, one package of Nutrient is included.
I bought some different plants but mainly so-called “Experimental Packs” which contain everything except the seeds.
I used these to plant some edible flowers which I plan to use for decorating some of the more complex meals I prepare.

Experimental set with three containers plus a pack of nutrient.

After about a week or so, the seeds started growing and I had to put in the first height module. I used a Blooming light to boost plant growth.

The first height module is added, in this case a Blooming Light Height Module.

A few weeks later, I had a jungle in my kichen.
Meanwhile I was able to harvest the first edible flowers.

My kitchen-jungle

One thing you will notice in the photo above is that my plants grow at a different height.
Normally you should use plants that grow at a similar speed.
In my case the higher plants take the light of the lower ones, significantly influencing their rate of growth.
Because I wanted to grow edible flowers, I had bought mainly so-called “Experimental Packs” from Bosch and got the seeds elsewhere without knowing how high the plants would grow. With a little more experience, I’ll make sure I use plants that don’t grow too high in future.
I find the price for the original seed-packs rather steep but I guess that’s the price you pay for being an early adopter.

Do you need this SmartGrow-system in your kitchen?
Not necessarily. It’s quite expensive and offers only limited space for plants.
On the other hand though, it’s fascinating to see the plants grow and you can also grow exotic spices and herbs during the dark winter season whoch normally wouldn’t grow here in Central Europe.
Would I buy it again?
Yes, I definitely would. Not only because of the great plants I can grow here but rather because I find the technology fascinating.
I believe this may be the future of urban gardening on a larger scale and I’d like to gather some experience in this field.

Preparing Meat in the High-Temperature Top-Heat Grill

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I’ve been using a high-temperature top-heat grill for some time now and I must say: I love it! Never before have I had meat this tender and yet with such a nice crust.
The setup of a top-heat grill is simple.
Located at the top is the burner.
Below this there are runners for adjusting the height of the grate.
All liquids are collected in the grease drip-tray at the bottom of the grill.
The whole insert is removable. Once the grill has cooled down you can just take it out and clean it in the dishwasher.

Top-heat grills come with a max-temperature of 850 Degrees Celsius (that’s 1,562 Degrees Fahrenheit for those still using the outdated imperial system).
This is really hot, but to be honest, this is measured directly inside the heating-element. The temperature on the surface of the meat is approx. 600 Degrees which is still well above the minimum temperature of 400 Degrees required to achieve the “caramelizing” effect that comes with the Maillard-reaction. This causes a chemical reaction which leads to an extremely tasty crust.
There are two types of top-heat grills: those that run on propane gas and electric grills.
As I use my grill inside, I decided to buy the “Steakreaktor” from Klarstein.
Using a gas-grill inside is dangerous as the grill burns a lot of gas in a very short time to achieve and maintain the high temperature. Especially in a small kitchen this may lead to a lack of oxygen and a high concentration of Carbon-Monoxide, a possibly fatal combination.
For the test, I took two nice chunks of organic steak.

Before going on with preparing the meat make sure that you turn on the grill and set it to the highest possible temperature.
For the Steakreaktor this will be “Hotter than Hell”.

The grill will heat up within approx. two minutes.

The steaks were salted using Black Lava Salt which, as I find, gives the meat a great flavour.
Never add pepper at this stage! With the temperatures the grill reaches, pepper will burn and cause an unpleasant bitter taste, spoiling the meat.

The meat is then placed on the grate of the grill.
Here, you need to take care to place it as far back as possible to make sure that it’s located under the burner.

The meat is then pushed into the grill.
Make sure that it’s located as close to the burner as possible. Not too close though, as under the heat it will rise slightly. If it then touches the burner it will slide off the base-plate when you pull it out.

After a few minutes (depending on how well done you like your meat) you pull out the grate and turn over the meat.
Personally, I like my meat very rare so I do it approx. 3 minutes on each side.
If you take your meat from the Sous-Vide you’ll want to grill each side for approx. 45 seconds.

Here you can see the great crust you get from a top-heat grill.
If you look closely at the example, you’ll see that the meat was placed slightly too far to the front of the grate. About one centimeter of meat wasn’t directly under the burner so it doesn’t have a crust.
Liquids that ooze from the meat are collected in a small tray at the bottom of the grill.
As you can see on the photo, only a tiny quantity of juice and fat actually ran out of the meat. The high temperatures will cause the Maillard-reaction to start almost immediately, effectively sealing the surface of the meat and keeping nearly all liquids inside the meat where they belong.

Sous Vide: A Great Way to Cook

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Sous Vide, one of those terms you run across a lot nowadays, It’s kind of hyped but still seriously underrated.
I love my Sous Vide, the results are absolutely awesome.
I don’t only use it for classical Sous Vide recipes but also in many cases where a recipe requires cooking something in water.
Now, when you cook something in water and you taste the water afterwards, you’ll most probably find that the water tastes strongly of whatever you cooked, be it meat or vegetables.
In some cases this may be the desired outcome, e.g. when you prepare a chicken soup. In many cases though. the water will be poured away after cooking with all the aroma literally going down the drain.
Because what aroma is in the water was once inside what you cooked and there is no way of getting it back in.
If you ask yourself why your vegetables taste so “flat”, not at all like those you get in a good restaurant, this is the reason. But you can change that of course.
Simply by putting the vegetables into a plastic bag, creating a vacuum in the bag and sealing it, then placing it in the Sous Vide bath for a few hours at a temperature between 60 and 70 degrees.
You’ll be astonished by the difference in the aroma.
I will be publishing some Sous Vide recipes over time where I’ll explain the different techniques in more detail.

Which type of Sous Vide?
Basically, there are two types of sous Vide. One is a longish device which you just put into an existing pot, heating up the water in that pot to a given temperature and maintaining this temperature.

The other is a device like that shown in the picture at the top of this article.
It’s a complete device including a water-container.

Personally, I would always prefer the complete device. First of all, the heat comes from all sides, ensuring that there are no zones with significally different temperatures in the water.
Then it has a lid. The Sous Vide which you place into a pot doesn’t have this. As it’s attached to the side of the pot, you can’t close the lid.
For one, this means that a lot of energy is lost. Heat travels upwards and your Sous Vide will consume a lot of power if you keep it running for several hours. 
The fully encapsuled device doesn’t have this problem. The lid ensures that most of the heat stays inside, requiring far less energy to maintain the desired temperature.
Also, the lid keeps the water in. Over the long periods required for Sus Vide cooking, water will evaporate. Replacing it with water of a different temperature may have a negative effect on the cooking progress.

Pricewise, there isn’t really much difference between these two types. It’s really more a question of the space they consume when stacked away.
If you have enough space, you should really go for the full device.

Seriously Overrated: The Juicer

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I think one of the most overrated tools in the kitchen is the juicer.
If you own one, how often do you really use it? And what do you do with it?
Mine (which you see on the photo) is now over one year old and I’ve used it maybe two or three times.
All I use it for is juicing tomatoes. I haven’t used it for anything else yet.
When I bought it I thought “Wow, a juicer! I’m going to do so many cool things with it.”
After using it for the first time, when I had to clean it, which was a hassle and really time consuming, I though “Wow, what a freaking lot of work, just for a few juiced tomatoes.”.
In the end, I didn’t even find any recipes where I needed so much fresh juice that it was worthwhile using it.
In 99% of the cases, I find it easier just cutting stuff up and straining it through a cloth. This takes a bit of time and is quite a lot of work but in the end still less time consuming than having to clean a juicer.
For juicing tomatoes though, it’s brilliant.
A lot of my recipes from the Molecular Cuisine contain tomato-water.
Even though tomatoes are red, tomato-water is actually yellow, at least of you manage to get out all the meat, skin, etc. This really works best with a juicer.
The yellow tomato-water has a very intensive tomato-flavor.
You can easily turn it into a foam with Lecithin, make tomato gummi-bears using Agar Agar, create tomato spheres, etc.
That’s another story though. But anyway, that’s the only use I’ve found for my Juicer so far.
If you have any other uses, please leave a comment.