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Create a perpetual-horizon planner from laser-cut plywood and acrylic using just wood glue and duct tape.
This is a rolling erasable planner which shows the right day and date for any 4 consecutive weeks in any millennium. The rotating and sliding mechanism means it can be reconfigured at the end of each week with the minimum of effort.
From constructing prototype perpetual calendars for friends and family christmas presents I've learned some things to do and things to avoid with when fabricating this design in particular. For this instructable I wrote up some instructions and published our laser-cutter files under a creative commons license. To test-run, Clare had a go at following the steps while I took the pics you see here.
There is plenty of scope for looking at it as a reference design and cobbling the same thing from found parts or experimenting with your own fabrication methods to replicate the loops of numbered tiles.
If you like the project, please rate it or vote for it in the Gorilla Glue contest. Skip to the last step for a rough and ready demo video.
This is a rolling erasable planner which shows the right day and date for any 4 consecutive weeks in any millennium. The rotating and sliding mechanism means it can be reconfigured at the end of each week with the minimum of effort.
From constructing prototype perpetual calendars for friends and family christmas presents I've learned some things to do and things to avoid with when fabricating this design in particular. For this instructable I wrote up some instructions and published our laser-cutter files under a creative commons license. To test-run, Clare had a go at following the steps while I took the pics you see here.
There is plenty of scope for looking at it as a reference design and cobbling the same thing from found parts or experimenting with your own fabrication methods to replicate the loops of numbered tiles.
If you like the project, please rate it or vote for it in the Gorilla Glue contest. Skip to the last step for a rough and ready demo video.
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Signing UpStep 1The Problem
The visible horizon of conventional monthly calendars shrinks as time passes. On the last day of the month, even tomorrow isn't visible! Waxed paper calendars aren't reusable, unless you're very patient, and they are destined to end up in landfill.
They are also covered in kittens, so you have to hide them round the side of your fridge so visitors don't feel ill from the kitsch intensity.
A SOLUTION
A perpetual horizon calendar always allows you to see a certain distance ahead into the future. New weeks slide into view as old weeks are retired. Since it lasts forever, you can make it from more expensive materials. You can invest in personalising the design to your taste and put it on show.
Replacing the tired old format of the paper calendar is something of an engineering and mathematical challenge. To achieve both correctly numbered day tiles and correctly labelled day columns a mechanism is needed with both a horizontal and a vertical rotation of carefully chosen tile sequences.
Rotating vertically allows you to slide old weeks out of view above, and new ones into view below. Rotating horizontally allows the day headers to line up with the numbers. It also permits the 1st of the following month to follow on from the 28th, 29th, 30th or 31st of the previous month, depending on what's needed at the time. In combination, these two axes mean the planner can represent any possible future date range in the Julian calendar.
[Credit: flickr's swirlingthoughts and artolog for CC-licensed calendar and kitties.]
They are also covered in kittens, so you have to hide them round the side of your fridge so visitors don't feel ill from the kitsch intensity.
A SOLUTION
A perpetual horizon calendar always allows you to see a certain distance ahead into the future. New weeks slide into view as old weeks are retired. Since it lasts forever, you can make it from more expensive materials. You can invest in personalising the design to your taste and put it on show.
Replacing the tired old format of the paper calendar is something of an engineering and mathematical challenge. To achieve both correctly numbered day tiles and correctly labelled day columns a mechanism is needed with both a horizontal and a vertical rotation of carefully chosen tile sequences.
Rotating vertically allows you to slide old weeks out of view above, and new ones into view below. Rotating horizontally allows the day headers to line up with the numbers. It also permits the 1st of the following month to follow on from the 28th, 29th, 30th or 31st of the previous month, depending on what's needed at the time. In combination, these two axes mean the planner can represent any possible future date range in the Julian calendar.
[Credit: flickr's swirlingthoughts and artolog for CC-licensed calendar and kitties.]
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Suggestions from other makers are always gratefully received, but even more so from people with hands-on experience of rolling their own.
If you don't like the fonts or have a different material in mind it's fairly easy to change things from my end, though this particular design has been battle tested by building it a few times.
If you're interested in requesting major structural mods or changes to materials, the resulting untested design will be a bit of an unknown quantity. Not a problem if you have access to a laser cutter and can afford to experiment without major expense.
I've wondered what it would be like at half-scale, for example, which should work fine. Currently it's the size of an LP, so that would scale it down more to CD size - cute. Might also be a good way of testing out a modded design cheaply.
Look forward to hearing from you.
The idea of a "Horizonless" calendar is just fantastic. The more I think about it, the more I want to make one. Of course, I'll have to squeeze it in with my million other projects, so we'll see if it actually goes anywhere!
If I do end up making this I'll probably try and do it by hand (or by power tool) rather than by laser. I will definitely let you know if it goes anywhere, I know how much I like it when someone shows me a picture of their version of my instructable.
There's a limitation on scaling up v0.2, because it has a one-piece outer border and a laser-cut backboard. That means that the scale is limited by the maximum dimensions of the laser bed. I've only come across beds up to about 750x360 so far, and given the design is square, that means max edge of 360mm.
v0.1 was different - it just had laser-cut tiles and separators glued to a big bit of plywood which wasn't laser-cut.
Consequently the tiles and panels were about 50% bigger in linear dimensions - a whole lot more area to write in. I still have one set of these larger prototype laser-cut loops and panels and don't have a use for them as I dropped this design in favour of v0.2.
If you wanted to make a frame for the bigger loops we could come up with some kind of deal to mail them to you at cost...
http://tacticalendar.co.uk/assets/svg/v0.1/
[Note the lines on these SVGs are so thin you can't see them, but they ARE there - use View => Display Mode=>Outline in Inkscape or just select all and change stroke thickness]
The problem with the v0.1 design was that you had to move every panel up manually by sliding it out horizontally and sliding it back in above. Having a complete retaining frame gives you the benefit of everything sliding up in one movement.
Of course, all of this comes down to the fact I'm rubbish at woodwork, but good at software. Making v0.2 by hand on a larger scale would be quite doable.
I had a moment of excitement when I thought I could get rid of one or more of the week panels and finally solve pesky issue 32, but I can't actually get the sequences to work out simply without the blank panels...
http://github.com/cefn/Tacticalendar/issues#issue/32
If I'd managed to drop one or more panels, then I could begin to scale up the design even without changing the laser bed as it would no longer be square.
If anyone has any suggestions how I could elegantly make up a complete retaining frame from laser-cut pieces without a one-piece face board, I'm definitely interested as I think a lot of people would prefer it bigger.
The laser cutter files typically require REALLY THIN lines, which can be entirely invisible in a regular viewer. For example Ponoko has lines 0.003mm wide. Making them visible typically needs an editor, followed by either changing the view style, or actually modifying the thickness of the lines.
There's a chance there's some other kind of problem with the SVG files, but loading them in the free and open source SVG editor Inkscape and choosing View => Display Mode => Outline does the trick for me. Alternatively CTRL+A - Select All followed by CTRL+SHIFT+F - Fill and Stroke should enable you to change the stroke (line thickness). From Inkscape you can then export them to anything which suits.
I recently also uploaded PNGs into the folder alongside the SVGs at http://tacticalendar.co.uk/assets/svg/v0.2rc2/ so if you're just curious regarding the design (don't need to actually send them to a laser cutter) then these should be viewable in pretty much anything.
Your issue 32 is a bit of a brain bender! I read through the comments in that section and it's a bit much for me after a day at work. I don't see why a single strip with rearrangeable tiles wouldn't work, and being the dork that I am I liked the idea of neodymium magnets. Is there something I'm missing there?
I might be interested in getting those tiles from you. I was thinking the hardest part would be making those all uniformly sized. I'm kind of the opposite from you, rubbish at software and good at woodworking, but not that good. My Grandpa used to build miniature chessboards, about 3 inches square and all the little tiles were exactly the same size, but I don't have his skill (or his collection of tools). I'll let you know if I get to a point in planning this that I'd need those tiles.
http://github.com/cefn/Tacticalendar/issues#issue/32
It's an intriguing problem to design 'crossover loops' which can directly connect the preceding month to the following month.
I'll see if I can articulate the problem, as much as I understand it.
First a solution - the trick in the tacticalendar design is the blank panels. The routine for the user is very simple - put the old week as a new week. If it doesn't fit there, you have no choice but to fold it blank. Folding it blank means it's been skipped; so by this mechanism you can assign a different number of panels to each month.
Why is this relevant? Blame Julius Caesar!
The number of days in a month is 30.5 on average in a typical year. Of course, individual panels assigned groups of 7 (one week per panel). meaning 4.357 7-day panels assigned to representing an average month.
This introduces a systematic drift. If you try to use a whole number of panels for each month then you eventually when you try to place a panel as a new week you find it doesn't have the numbers to represent the date range you need - it either falls short (4 panels) or overshoots (5 panels).
Skipping a week by hiding it in plain sight becomes critical to the simplicity of use, since keeping the strict sequence means the user doesn't have to deal with all this craziness directly, but just has to fold the upcoming panel so it fits.
You need to allocate a minimum of 4 (28 days) and a maximum of 4.428 (31 days) panels, with a frequency which averages out at 4.357. To complicate things, because the numbers don't align with weeks, that means that sometimes a month has for example 0.143 of a panel(1 day) at the tail of the beginning week, 4 full weeks, and then 0.214 of a panel (2 days) at the beginning of the tail week.
To handle this kind of not-so-special case, a month needs to be able to spread over between 4 and 6 physical panels, which constrains the assignment of numbers to loops even further.
I think it means that you need at least two sequenceable (magnet or velcro) panels to be capable of handling the crossover. I'm still not sure how the drift problem is solved, yet, in such a design. This is why I'm stuck.
Experimentation is the key, though. Check the size of panels in v0.1 (the SVG is measured in mm - you can change the viewing units in Inkscape to check). The set I have is currently bound into duct-taped loops but it would be easy to repurpose them to anything by just taking the duct tape off the back.
I've tinkered with origami-style and scroll paper yearly calendars with different horizon times. Nothing viable to share :-(
My calendar solution now is to use two single page yearly calendars for the raw dates, holidays and visual blocking out of vacation and red letter days. Plus a simple word processing file with detailed appointments and color coding. I cut and paste the next few weeks and share by rich text email. Been using this for ten years for family calendaring and it works for me.
Now back to your mechanism. Somehow I see a puzzle or game toy here which looks commercially viable. I'd say think along those lines and show it to a manufacturer. They may rip you off, but they might not, and royalties are a nice thing :)
Being ripped off or not is certainly a hot topic in the world of makers and inventors. I'm hoping to leapfrog the whole thing by concentrating on making useful stuff for people without too many liberty-reducing interventions like patents to beat people over the head with.
That's what the Enigmaker initiative was about in many ways. The tacticalendar is the first concrete project to be properly documented and distributed out of that pool of experimentation.
If I'm lucky I'll eventually find a niche where people actually want to pay me because I'm giving them something consistently useful, and this will help cover my increasingly expensive taste in lasers.