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Primitive Technology: Water powered hammer

Various techniques used to build a water-powered hammer or “monjolo”.

I like the technique he uses to bore the hole in the log and make the trough: hot coal, blow pipe to make it hot, clay to protect the edges and direct the burning.

The key is finding out where the balance point of a log is (might not be the center, logs taper) after gouging out the water-catching trough on the back side.

As the trough fills with water it tips the log and spills the water all at once and the log’s other end falls.

Many different technologies and ideas involved in this brilliant machine. No doubt it took quite a bit of trial and error to get it right.

I’ve seen similar pieces of technology in Japanese gardens (in Japan and in Los Angeles) called Shishi-odoshi.

There are many more of these great videos at the Primitive Technology site and for those who prefer, he has a Primitive Technology YouTube Channel.

[via The Kid Should See This]

Primitive Technology: termite clay kiln & pottery

Digging clay out of a termite mound, using straw to reinforce it, and making a crude but very effective kiln to fire clay pieces to be used as roof tiles, a water jug, a blower and more. Brilliant.

There are many more of these great videos at the Primitive Technology site and for those who prefer, he has a Primitive Technology YouTube Channel.

[via The Kid Should See This]

Adding weather to Calendar in Mac or iOS

Weather in your iOS and macOS Calendars

I use Apple’s native Calendar application in Mac OS on my MacBook Pro as well as in iOS on my iPhone 6s and iPad Air II. I’ve used other calendars but there’s something about the simplicity and integration of Apple’s native apps that appeals to me.

I think the reason I didn’t think to attempt to include a weather forecast in my calendar on my Mac before was that I was used to using both the weather widget and a third party widget called Radar in Motion in Mac OS’ Dashboard.

Radar in Motion stopped working a while back and while I have weather set up in my Mac Notification Center (off the right side of the screen), I thought it would be more useful to attempt to integrate a weather forecast into Calendar so I could see both events and weather in the same place.

A few minutes of searching and I found Chris Short’s post above which covers adding a Weather Underground ICS calendar subscription file to almost any calendar, including Mac OS’s Calendar. Note, I’ve not tried this directly on an iPhone or iPad but it should work.

I copied this sample URL into my browser:

and changed the state and city:

Note, before you go and do this, please read the following:

I’ve made numerous categories (calendars) in my Calendar: Home, To Do, Event, Hiking and I’m subscribed to Holidays. I color code each of these calendars and it helps me quickly look at my Calendar and see what’s what. I’ve been doing this for many years, since iCal first appeared.

If you don’t make a new category/calendar called something like Warren Weather” and you go too fast through pasting the URL in your browser, downloading the ICS file and adding it to your Calendar, you may accidentally add the weather subscription to one of your existing categories. I did this by mistake and could not, for the life of me, figure out how to undo it. Couple that with the fact that my Calendar is connected to iCloud and immediately synced with my iPhone and iPad and you have a potential issue if you make a mistake.

I recommend creating a new category/calendar called “Weather” or better, “Warren Weather” (substitute your town/city) and when you download the ICS file add it to that category/calendar and give it a unique color.

calendar detail

The last thing to consider is that this ICS file is for a particular place and it will not change if you travel from, for example, Warren, Connecticut to Chicago, Illinois. If you can figure out how to modify the ICS file to make it GPS aware, please let me know. But, short of that, if you find yourself in another city, make a new weather category/calendar for that city and click the X off in front of your home city to hide it temporarily.


Looks like we’re going to have some snow on Tuesday and I’ve got an appointment I might have to move. Brilliant.

The mathematics of sidewalk illusions

Brilliant, the best explaination of this I’ve ever seen.

“Have you ever come across an oddly stretched image on the sidewalk, only to find that it looks remarkably realistic if you stand in exactly the right spot? These sidewalk illusions employ a technique called anamorphosis — a special case of perspective art where artists represent 3D views on 2D surfaces. So how is it done? Fumiko Futamura traces the history and mathematics of perspective.”

[via The Kid Should See This]

Primitive Technology: food production

Two great videos, one on making traps to trap crayfish (freshwater shrimp) and the other on making a potato garden.

Both involve using a hot rock to boil water to cook things rather than putting a container over a fire, an amazing idea in itself.

There are many more at the Primitive Technology site and for those who prefer, he has a Primitive Technology YouTube Channel.

[via The Kid Should See This]

Primitive Technology: Tiled Roof Hut

This is a fantastic process video on making the “ceramic” or fired mud tiles for a hut. Another brilliant piece and this one particularly dear to my heart because of my background in ceramics.

There are many more at the Primitive Technology site and for those who prefer, he has a Primitive Technology YouTube Channel.

[via Dale Allyn]

Disassembling the Ricoh GR for sensor cleaning

One of the great things about Flickr is that there are groups of people with similar interests who not only post images, but also have discussions about issues with cameras and other aspects of photography. I’ve been a member of lots of groups on Flickr since joining in 2004 and currently I’m a member of a few Ricoh GR groups. One of them has an ongoing discussion of the Ricoh GR’s problems with dust and I’ve been tracking it: how do/did handle the dust issue?. The other day one of its members, Jamie Collinson, posted a link to a post he’s written on disassembling a GR and if you’re a GR user (or even if you’re not) it’s worth taking a look at and bookmarking for possible future use:

A guide to disassembling the Ricoh GR for sensor cleaning

Many people have had dust issues with the Ricoh GR. It’s both a cult favorite camera and a rather fragile beast. A theory is that it’s retractible lens (the lens telescopes out of the camera when its turned on, then retracts into the body when it’s turned off) is acting like a bellows and pulling dust in when it moves. Another is that the seals on the camera aren’t doing their thing.

If you have a GR and you’re not sure if you’ve got dust on your sensor, the standard test is to stop down (close the aperture) to f/16 and focus on and shoot a clean white wall or a clean sheet of white paper. You’ll see the dust spots (as hopefully differentiated from dirt on the wall or paper). Or, you may have seen spots in clear skies that are shot at small apertures.

I don’t think its worth doing this surgery for a single dust spot when you can easily clean it up with an image editor like Lightroom but people who get dust in their cameras generally have a number of spots and that can be a tedious clean up process (in software).

If you generally shoot with an open (wide) aperture you’re less likely to see the dust, unless you’re really loaded with it, it generally only shows up at smaller apertures.

It’s worth it to have a look at Jamie’s post just to see what the inside of the Ricoh GR looks like, he’s got great pictures.

The only thing I’d add to his otherwise excellent post is a technique I learned doing surgery on early Macintosh computers (mostly powerbooks and early MacBook Pros) with small sets of different sized screws that might get mixed up. List the steps of the disassembly on a piece of paper and pile the screws next to their corresponding steps. For example, in his post with 7 steps, one might divided a piece of paper into 8 boxes, put a number in each box and put the corresponding screws in a box. Just make sure to not move the paper.