The inspiration for this Instructable is my book “Practical Perpetual Calendars – Innovative, Convenient and Green” by James R. Saltvold, 2017. A pdf copy of it can be viewed at https://archive.org/details/9781532021367PdfOfBook . My book describes the unique concepts that I have developed for making standalone perpetual calendars, and suggests applications for these concepts. One suggested application (see pages 68 to 70) is pocket calendar. This Instructable shows how the concepts in my book can be used to make a small pocket calendar that is the size of a credit card. The calendar can display any month in a 50-year period, with the calendar in this Instructable covering the years 2000 to 2050. It will fit into a standard 2.25 by 3.5-inch gift card or coin envelope and is the same size as common pocket calendars that only cover one year.

My previous Instructable “Perpetual Calendar Breakthrough” (https://www.instructables.com/Perpetual-Calendar-Breakthrough/ ) describes how to make a tent desk calendar that uses the same concepts as the credit card size pocket calendar. That Instructable also describes various perpetual calendars and shows how ones that use my concepts have many advantages.

Supplies

The following supplies are needed:

Quantity Description

1 8.5 x 11-inch sheet of 60 lb or heavier glossy cardstock (see Note 1 below)

1 2.25 by 3.5-inch gift card or coin envelope (see Note 2 below)

1 small container of Mod Podge or white glue

Notes

1. Cardstock that is 80 lb. or heavier cardstock is preferable to 60 lb, but it is too heavy for most home printers. A glossy finish is essential for smooth operation of the sliding part. If you do not have any glossy cardstock, an option is to use standard cardstock and cover it with Avery 76293 or equivalent self-adhesive laminating sheet. Another option is to have the printing done at printshop that has suitable cardstock. If you decide to buy cardstock, a product you might consider purchasing is Hammermill HAM120023 Color Copy Digital Cover Paper. For more information on cardstock, see https://finecardstock.com/topic/cardstock-weight-guide/ .

2. Stationery stores typically sell coin envelopes in packages of 50 or more. Try to salvage an envelope from a gift card, credit card or a hotel room card. The photo above shows a salvaged envelope, which has the bottom flap on the outside. This is the preferred construction. Some envelopes have the bottom flap on the inside. When the calendar is inserted into these envelopes it can catch on the flap and not go all the way to the bottom.

Step 1: Look at the PDF Files

There are the following pdf files:

1. Pattern for Moving Slider Calendar

2. Pattern for Moving Window Calendar

3. Notes on Calendar Construction and Excel

Only one of the first two files is needed if you want to duplicate one of my calendars exactly. The third file is useful to understand more about my perpetual calendar designs and how to use Excel to modify my patterns and make new patterns. This file has enough information to enable you to duplicate the Excel files that I used to make the patterns.

Step 2: Choose the Type of Calendar

As indicated in Step 1 there is a pattern for a moving slider calendar and a moving window calendar. Both are good pocket calendars. In the image above, the moving slider is on the left with the base shown in white and the moving slider shown in light gray. The moving window is on the right, with the base shown in white, the track shown in light gray, and the moving window shown in light blue. I prefer the appearance of the moving slider type. The instructions can always be seen, whereas in the moving window calendar the instructions are covered by the window in some positions. However, the moving slider calendar has the disadvantage that the end of the slider is beyond the limits of the base in most settings so the calendar is longer than a coin envelope when it is set. Thus, to avoid having the slider stick out beyond the envelope, you may not be able to leave the calendar set at the current month when you put it back into the envelope. This disadvantage can be overcome by printing the moving slider calendar at a smaller font than the moving window calendar, but the font in my patterns is quite small.

Step 3: Make a Moving Slider Calendar

After finding suitable cardstock, print the pattern for the moving slider calendar on the cardstock. There are two parts – the slider and the base. I used 60 lb cardstock and covered it with self-adhesive laminating sheet after printing. If the pattern is to be covered with self-adhesive laminating sheet, use a small flathead screwdriver to make score marks on the dashed lines at the ends of the sliders before covering with laminate. If not covering with laminate, make these score marks before doing any cutting. The pattern shows a dashed line below the Date of Easter Sunday table. This table is optional. If using it, also make a score mark along this dashed line. If not using it, cut along the dashed line when cutting out the base.

Use a utility knife and a straight edge to cut out the pattern. A metal straight edge is preferred. Plastic will work but it is more easily damaged if the utility knife slips. Put an old magazine under the cardstock before cutting. Self-healing cutting mats are available, but I have found that an old magazine works quite well. Cut the two slits on each side of the window first while you still have a large sheet to hold. The remaining cutting can be done in any order. The final step is to cut the corners of the left end of the slider so that it can be easily threaded through the slits.

The next step is to install the slider. Start at the right side of the window with the slider on top of the window piece. Push the left end of the slider through the far right slit so it is under the window piece. Then push it through the slit on the right-hand side of the window so it is back on top of the window piece. Repeat on the left-hand side going under and back up. If the slider is wider than the slits, use the utility knife to enlarge the slits.

After the slider has been threaded through the slits, cut off the part of the left-hand end that had the corners cut off. Then fold under both ends and glue them to the bottom of the slider. The folded-under part in each end makes the slider more durable for pushing or pulling.

If the Date of Easter Sunday table is used, fold it back and glue it to the back of the base. Be careful not to get any glue in the area of the slits where the slider travels,

Step 4: Make a Moving Window Calendar

After finding suitable cardstock, print the pattern for the moving window calendar on the cardstock. There are three parts – the moving window, the track and the base. I used 60 lb cardstock and covered it with self-adhesive laminating sheet after printing. The pattern shows a dashed line below the Date of Easter Sunday table. This table is optional. If using it and the pattern is to be covered with self-adhesive laminating sheet, use a small flathead screwdriver to make a score mark on the dashed line before covering with laminate. If not covering with laminate, make this score mark before doing any cutting. If not using the Date of Easter Sunday table, cut along the dashed line when cutting out the base.

Use a utility knife and a straight edge to cut out the pattern. A metal straight edge is preferred. Plastic will work but it is more easily damaged if the utility knife slips. Put an old magazine under the cardstock before cutting. Self-healing cutting mats are available, but I have found that an old magazine works quite well. Cut the slits on each side of the window first while you still have a large sheet to hold. The remaining cutting can be done in any order. The final step is to cut the corners of the left end of the track so that it can be easily threaded through the slits. Note that the track has the same tables as the slider in the moving slider calendar.

The next step is to install the track. Start at the right side of the window with the track under the window frame. Push the left end of the track up through the slit on the right-hand side of the window. Then push it down through the slit on the left-hand side of the window so it is back under the window frame. If the track is wider than the slits, use the utility knife to enlarge the slits.

After the track has been threaded through the slits, cut off the part of the left-hand end that had the corners cut off. Then glue the ends of the track to the base. Apply glue only on the shaded areas of the base and avoid using an excessive amount. If the Date of Easter Sunday table is used, fold it back and glue it to the back of the base.

Step 5: Using and Understanding Your Calendar

The instructions on the calendar simply say:

1. Set month over year.

2. Leap years are bold.

3. Ignore 29, 30 and 31 as applicable.

In the month table on the slider or track, the top row applies to January and February of a leap year, the middle two rows apply to March to December of all years, and the bottom row applies to January and February of a common year. To bring attention to leap years, JAN and FEB are in bold in the top row and leap years are also in bold in the year table. The calendar always displays 31 days for the month, with 29, 30 and 31 to be ignored as applicable.

If you imagine that the columns in the year table are labeled Sunday to Saturday from left to right, common years are under the day of the week that January 1 falls on and leap years are under the day of the week after the day that January 1 falls on. In the month table, the months are in columns that the day of the week that first of the month falls on relative to the day of the week that the first of January falls on.

To maximize the number of years in the limited number of rows of the year table, there are no empty cells. Thus, the first four rows in the year table are:

2000 2001 2002 2003 2009 2004 2005

2006 2007 2013 2008 2015 2010 2011

2017 2012 2019 2014 2020 2021 2016

2023 2018 2024 2025 2026 2027 2022

If there were empty cells, the table would be:

2000 2001 2002 2003 2004 2005

2006 2007 2008 2009 2010 2011

2012 2013 2014 2015 2016

2017 2018 2019 2020 2021 2022

Finding a year in a compacted table is a little more difficult than in a table that is consecutive with blanks, but having more years in an advantage.

Step 6: Solving Problems With Your Calendar

In addition to displaying the current month, your pocket calendar can be used to solve date problems. One is to find which day of the week your birthday is on for any year. Suppose your birthday is May 17, and you want to know the day of the week in 2030. Set May over the year column that contains 2030, and note that it will be on a Friday. You can also find the years that your birthday will be on a particular day of the week, say Sunday. Set 17 under Sunday, and under May note the years 2026, 2037, etc. Sometimes you can use the calendar to guess a date. A co-worker tells you on June 14, 2024 that tomorrow is her wedding anniversary. You forgot which year she was married, but you know it was on a Saturday. Set 15 under Saturday and under June note the years 2002, 2013 and 2019. You also know that she has been married for more than five years, but less than 20. Therefore, she was married on June 15, 2013.