High-Flying Project: Reconstructing the Junkers J1

Ever happened to you? You lose sight of a former colleague or fellow student and then, years later, you stumble upon an awesome project, just to discover that exactly this colleague is involved. When I learned that there will be a kickstarter campaign to reconstruct the first all-metall aircraft, the Junkers J1, I, as a technology enthusiast, was excited.

The Junkers J 1

The Junkers J1, undergoing flight preparations in late 1915 in Döberitz, Germany

Even more when I learned that Fabian, my fellow Museum Studies graduate and colleague from the days we developed the clay brick exhibition at the Deutsches Museum in Munich was involved. Of course I had to support the campaign, so here he introduces the project:

Dear Collegues,

we start on May 2nd, one of the largest support campaign for a museum project in Europe at Kickstarter.

It is one of the most important pioneer aircraft, the Junkers J1 that should be reconstructed in a 1:1 scale model. The J1 was the world’s first all-metal aircraft and it had its first flight 100 years ago. It was such an important masterpiece of aviation, that it was exhibited in the Deutsches Museum Munich. However, the plane was unfortunately completely destroyed by a World War II bombing raid.

Our campaign will to support the detailed reconstruction by the technical museum “Hugo Junkers” in Dessau. Please help us to make our campaign a success by posting the J1 Project page (www.facebook.com/j1project). Join in at our Kickstarter campaign (www.j1-project.com/start). For every amount donated, we have come up with something very special: a limited Junkers J1 wristwatch, a J1 model plane, a postcard set with 24 facsimile designs, aviator glasses and more.

Only when many supporters participate in the crowdfunding campaign, we can finance this ambitious project and rebuild the Junkers J1 on the basis of the original plans.

Many Greetings from Munich

Fabian Knerr


Waste Separation: What to do with old emails?

Oh, fear not, you who struggle with a crammed inbox. Just today a colleague sent me the ultimate answer to the question: “How to properly dispose of those spam mails, outdated telephone lists and irrelevant listserv postings?”



(In fact this crate was used to store a collection of enamel (German: “Email”) signs in the past who now have a new and better storage.)

Unmanaged Collections – Final Adjustments


Maybe you wonder how the book project about managing unmanaged collections is going. Well, last week I got the proofs from the production editor so at the moment I spend much of my free time proof reading. I contacted all the contributors so they can check their real-world examples and photo attributions and add their corrections.

In addition I’m creating the index which is not as easy as I thought. My assumption was that I more of less type a search term, let the computer scan the document, note the pages where the search term does appear and that’s that. Now I realized it doesn’t work that way. My experience with museum documentation could have told me that it doesn’t work that way… Here’s why:

Let’s say someone wonders if there is something about “deaccessioning” in the book. Well, there are a lot of pages where I talk about making decisions what to keep in the collection and what not, but chances are I did not use the term “deaccessioning” on those pages. Of course, the computer would skip those pages. So, as I read through the page proofs I take notes of keywords I think would make sense in an index and write down the page numbers.

I do this on outdated business cards, which I haven’t thrown away because you never know when you need a set of small but sturdy cards of the same size. Well, now, about 10 years after they became outdated they finally found their new purpose. I sort the keywords in alphabetical order so when I come across a term I already noted I can find it quick and add the next page number. I decided to collect broad, write down whatever I think might be helpful instead of being too restrictive. I will decide on the terms that will finally make it to the index at the end of the process. While “deaccessioning”, “collections policy” or “cataloging” will definitely make it to the final index, I’m not that sure about “Grandmother’s Fixes“, “upper management, dealing with” or “numbers, spellbound by”.

What is really interesting is that these cards even now show somehing like a topography of that book. “Hazards” seems to be the most important topic, with 12 mentionings thus far and I’m only half way through. Well, let’s see if it will stay that way. Onward! I have to meet that deadline so this book can be out in May.


This post is also available in Russian translated by Helena Tomashevskaya.

From “Kojak” to “Go-Jacks”

Go-Jacks Image : bendpak.com

Image : bendpak.com

This day you are translating an article for Registrar Trek, and you discover that what carriers call “Kojak” (term you thereby always use since you had to use it to move carriages) are called in reality “Go-Jacks”…


(Update of the vocabulary in my little head : done !)



Demonstration of the use of Go-Jacks : https://youtu.be/mush3hNbnmY
The article that enabled this discovery : Art work, Artefact, Auto, and Pop-Culture Shrine, Part 2


Préparation des « petites charriotes » qui seront visibles à la ré-ouverture de la Galerie des Carrosses du Château de Versailles dès mai 2016.  Image : © Aurore T

Preparation of the « little carts » which will be visible at the re-opening of the Gallery of Carriages at the Palace of Versailles in May 2016.
Image : © Aurore T

Awesome Picture of the Day: Box Construction

I work with a lot of awesome people. Of course I know that, but every now and then I even get a reminder. While tidying our packing space I found a piece of paper where one of our assistants has carefully constructed a custom box for one of our vacuum tubes. I couldn’t bring myself to just throw it away, I had to share it with all you packing nerds out there:

kiste roehren

Whooops – Little Registrar sent a note to you all, but shouldn’t have…

Dear Readers,

please accept my apologies that our faithful newsletter informed you about a post that was password protected. This was a mistake, as we are testing our new data logger at the moment and I needed a website to test if we all could have access to our climate dates from all over the world (or, in fact, from all our storages and offices). Didn’t have an idea that this would be sent out via our RSS feed just like any other blog post.

Well, anyway, to keep you in the loop: what is happening at the moment?

Over Christmas I was experimenting with arduino and other microcontroller boards. Of course, even if I try to do something just for fun, I end up doing something museum related. As I needed something to build, I built a data logger. And if it’s already built, why not take it to work with me?

There it glows... the experimentation zone at Christmas.

There it glows… the laboratory at Christmas.

At the moment one little prototype of the “Little Registrar” keeps a good watch over our climate in one of our offsite storages and sends its data to a website. And since this week this other little fellow records the climate in a storage room at our museum and logs it to a SD-Card:


As you see by the q-tip that serves as the restart button this is all in the prototyping stage at the moment. In fact, the “Q-tip Registrar” was a quick answer to an urgency call by our conservators. Assembled with parts I still had at hand, including an old cardboard box, a screw anchor, some ethafoam and, yeah, a q-tip.

Those who follow @RegistrarTrek on twitter know that I promised to write what we did and how and I will do, as soon as we passed the prototyping stage (and stopped creating e-mail bombs).

Have a great weekend, all!

This post is also available in Russian translated by Helena Tomashevskaya.

What happened September 2nd? A registrar’s climate mystery
Part 4 – Alternative Solutions

I hope you enjoyed our little climate mystery. A lot of our readers did and submitted possible solutions. Two people came up with the right solution in this case:
Geert Bellens suspected immediately that the logger was brought into another room and was right about this place:

”If someone was breathing close to the logger, the temperature would rise at 16:30, but humidity also. If a heat source was involved (local heater, lamp,..) I would expect rising temperatures, and lower humidity, but no that drastically.
I would think someone took the datalogger to another room (warmer, dryer) and then maybe outside in the car for a night, to put it back the 3th September…?”

And Michael Hall did a complete analysis that was accurate to the point:

”I would suggest that the logger was actually removed from it’s original location. The changes in humidity are being driven by the changes in temperature. Looking at the conditions before and after the fluctuations the conditions are fairly stable. The sudden change in temperature could be caused by someone accidentally putting the logger into their bag that has come from a warmer environment, walked out of the building allowing the temperature to cool, then got in a car,driven home with the air con on, got home at about 17:30, the car is left in the evening sunlight allowing the car to warm up before the sun disappears giving a gradual cool down overnight. At 07:30 next morning, the person drives into work, realises they have taken the logger home and puts it back in situ.“

Although those were the right solutions in our case, there were other solutions that are well worth considering when YOUR logger shows an odd graph like ours:

Christian Baars: “The weather was mild during early September 2013, with daytime temperature at around 24 deg C. However, your T changes are too rapid to be caused by normal daily fluctuations. The RH changes in this case are counter correlated with your T changes, which suggests that something affected T but confirms you have no independent RH control. As you say there is no HVAC an equipment malfunction can be excluded. Something lead to the steady then rapid T increase, then slow drop during the night, followed by rapid normalisation of conditions. Do you have central heating in the building which came on, the store got too warm, someone opened a window in the evening of the 2nd which was left open over night then closed in the morning of the 3rd?”

Kathy Karkut: ”Potentially something was dropped over the data logger such as a box or bubble pack, etc. and the readings are for a very small contained space surrounding the DL. The next time someone was near the DL they removed the covering.“

Chris Au: ”My first avenue of inquiry would be to confirm the integrity of the datalogger; was the data compromised in its collection, interpretation, storage or transmission?
Secondly, was there any other evidence of the T and RH fluctuation?
Thirdly, what are the items in storage? Could anything there be a cause?
Perhaps there would be clues in those answers.“

Hugh Glover: ”A staff member did something dry as they left for home and undid it when they arrived in the morning; not sure what they did though!”

Paul McAuley: ”I agree with Kathy Karkut, something has fallen over the datalogger unit creating a microclimate – a sheet of bubble wrap or tissue – or some creature has interfered with the sensor – or maybe there is a ghost in the machine…”

Pat: ”There was marked solar flare activity from Sept 1 to Sept 3 2013. Could that have had anything to do with disrupting the datalogger readings?“

The most interesting alternative solution, and something I really hadn’t thought about so far came from Doug Nishimura. We take it for granted that we – or the building and our technical appliances – control the climate conditions. However, sometimes it’s the other way round. The objects control the climate:

”I was going to comment that the places where temperature and relative humidity go up or down together (at least briefly) looks like the objects controlling the conditions. We’ve seen this in a historic house in which the attic went up and down in temperature with day and night. In the day, temperature would rise accompanied sometimes by a small dip in RH followed by a sharp rise in RH before plunging. As temperature peaked and started dropping, we might see a little upward spike in RH but followed by a sharp drop in RH as temperature fell before rising back up. This was the wood in the attic releasing water vapor as temperature went up (off-setting the expected drop in RH as temperature rose) and the adsorption of water back into the wood as the temperature fell again. We more recently ran into in a warehouse full of ceramic pottery pieces from archaeological digs. The clay was also adsorbing water as temperature went down and releasing as the pottery pieces warmed up.


I’ve included a pdf slide of on an experiment my colleague, Jean-Louis, did with sensors in a box of matted photographs. He actually had a sensor inside the stack, inside the box on top of, or beside the stack and outside the box. The large arrows point out the first points that show the effect of the material on the RH inside the box. So you see as the temperature goes up, the humidity sharply follows it up before talking a long slower slide towards equilibrium. When the temperature goes down, we get a sharp drop in RH followed by the long slow slide towards equilibrium. As we poked into data that people uploaded to eClimateNotebook, we noticed this pattern appearing surprisingly often and we figured out that if you start from an empty room with non-hygroscopic walls, the environment is what it is. We start adding objects into the room and the room controls the objects. Eventually you reach a point where the ratio of hygroscopic materials to free air in the room is just high enough that the objects start to control the room. We don’t really see it so much in temperature, although I point out that a ream of common office copy paper (and American copy paper is 8.5 X 11 inches or 215.9 mm X 279.4 mm and one ream is 5 pounds or 2268 grams) takes the same amount of heat in or out to change one Celsius degree as 3.64 cubic meters of dry air. Possibly the effect doesn’t show-up because of the slow thermal conductivity of paper, but it’s an example of what can happen.“

Keep watching your climate data, folks!

This post is also available in Russian translated by Helena Tomashevskaya.

What happened September 2nd? A registrar’s climate mystery
Part 3 – The Solution

“Looks like trouser pocket” said my colleague.

It wasn’t a trouser pocket, but it was the right lead. What we got here was definitely a people pattern. A storage area of the size at hand can’t change humidity by 20 % within 10 minutes if it is not to really catastrophic circumstances. It couldn’t be something that happened in the storage, it was something that happened to the logger.

Here’s the whole story:

The data from our data loggers is downloaded to a laptop at the beginning of each month, preferably on the first day of a month. September 1, 2013 was a Sunday, so September 2nd was the date for collecting the data.

On September 2nd about half past four p.m. our conservator responsible for the loggers called me to say that he just couldn’t make it to download the data on this day. But as we had a staff meeting on the next day and I was already at the offsite storage now, he asked if I could simply fetch the logger and bring it to the museum the next day.

Well, of course I could. I immediately took the logger and put it in my car so I wouldn’t forget it at closing time. While I was finishing my work at the offsite storage you can see how the poor logger lies in my car that was parked in the bright sun. About 20 minutes later I closed the storage and hit the road. As it was hot in the car, I rolled down the windows, resulting in a temperature decrease to a pleasant 25 °C (77 °F). At half past five I parked my car at home, again in the bright sun of a lovely, mild September evening. It was one of those last warm September evenings, where you can sit in front of the house with a cool drink and enjoy the warm rays of the setting sun. Apparently, it was far less pleasant inside of the car, hitting 30 °C (86 °F).

The next morning I got back into my car which had cooled down to 13 °C (55,4 °F) during the night. I was freezing, so I turned on the heating. When I found a parking lot in front of our museum at 8:10 the car was quite comfortably warm at 22,5 °C (72,5 °F). I took the logger and brought it to our conservator, so from now on the logger logged the regulated climate inside of our museum.

Hope you enjoyed our little real-world riddle.

The Start
The Hint

This post is also available in Russian translated by Helena Tomashevskaya.

What happened September 2nd? A registrar’s climate mystery
Part 2 – The Hint


I had a look at the graph. It looked like a pretty normal day in this area until about 16:40. We have a slow increase in temperature from about 21 degrees to 25 degrees Celsius (69,8 to 77 degrees Fahrenheit) and a drop in humidity from 60% to under 50%. Nothing odd for this less-than-ideal hall in the changing season of a German autumn. If you take a look at the weather dates of said day from the nearby weather station you can see that our inside correspondents with the outside: http://archiv.mannheim-wetter.info/2013/pcws/20130902.gif (thick green line for temperature, thin purple line for humidity).

Then, after 16:40 things got odd. We see a sudden increase in temperature up to 29 °C (84 °F) and a drop from 44% to 23% within only 10 minutes. If this weren’t odd enough, only 20 minutes later we see the temperature dropping back again to 25 °C (77 °F) and humidity slowly increasing to 32%. At 17:30 we see again an increase in temperature, climbing up to over 30 °C (86 °F) and staying as high until 19:00 to slowly, slowly start decreasing over the next few hours, reaching 13 °C (55,4 °F) at half past seven the next morning. Then, suddenly, the temperature increases, again in an unusual way, reaching 16 °C (60,8 °F) at 7:40, nearly 19 °C (66,2 °F) at 7:50, peaking to 22,5 °C (72,5 °F) at 8:10 to become quite stable again at 21 °C (69,8) and 57% relative humidity.

Again and again I looked at the data and discussed it with colleagues. Then, a colleague mumbled “Looks like trouser pocket.”

Suddenly I could see the whole story when looking at the graph. Can you?

The Start
The Solution

This post is also available in Russian translated by Helena Tomashevskaya.

What happened September 2nd? A registrar’s climate mystery
Part 1

I received a call from our conservation trainee. She was in the process of analyzing the climate from one of our offsite storage areas for 2013 and discovered something really, really odd. She sent me the data and asked if I could make sense of what happened on September 2 and 3 in the said year. Please see the graph below, showing the temperature in degrees Celsius (red line) and relative humidity in percentage (blue line) between September 2, 7 a.m. and noon on September 3. Can you make sense of what you see?


The data logger is a portable digital logger powered by batteries in the middle of a large storage area without HVAC that is approximately 2,000 square meters (about 21,500 square feet) and 5 meters (16.4 feet) high. In the next part we will discuss the graph and I will tell you the hint from a colleague that finally brought the solution.

What do you think happened in those 29 hours?

A Hint
The Solution

Full spreadsheet of data

This post is also available in Russian translated by Helena Tomashevskaya.