Double-Fan Adhesive Binding

The Double-Fan Adhesive Binding is a treatment we use in Preservation Services for new single sheet items with a good gutter margin such as theses or to repair worn out adhesive bound books.  Good margins are important as the process will trim 1/16" all around when finished.

MATERIALS

2 endsheets: cut to Height (H)
2 20-point boards: cut to Width (W) x Height of book
        (Can stack endsheets and boards to cut on guillotine)
Cloth lining: cut to H x [spine thickness + 2"]
Covering cloth: cut to H x [(W x 2) + spine thickness]
Double-sided tape
PVA glue
Tyvek optional 

PREPARE

Trim out of old case, leaving case intact, if possible.
Mark upper foredge of text with pencil mark (gets trimmed off later). 

 

Put rough-cut boards and endsheets into position with endsheet folds at foreedge to remain intact when cut.

Cut spine off.

 

 

 

DOUBLE FAN GLUE

Clamp into press screwing in the pressure equally.  Three loose bars are in the press (one has an L-shaped piece attached) with usual sized books.  Can remove one or more for bigger (wide and tall) book.

 Tip up the book to work on it.  Glue the spine once as it is straight up.  Fan it left and glue.  The fan it right and glue.  Squeeze the glued spine into shape.

  

 

CLOTH LINING

Glue up lining and set on evenly, pinching and pulling and smoothing.  Set onto spine and let dry about one hour.

 

BOARDS

With a pair of dividers run a score line 1/4" from the spine edge head to tail on each board.  Run a strip of 1/2" double-stick tape down the inside edge of the score line.  Flip the board over and glue the board up.  Now place glued side of board down onto text block lining up the spine with the double stick tape edge along the spine edge.  Nip for 30 seconds in press.                                                                                                                      

COVER WITH CLOTH or ORIGINAL PAPERBACK COVER

With new cloth:

Cut cloth to H x [(W x 2) + spine thickness].
Crease at the first spine fold.  Then make another fold 1/4" from this line (toward the foredge).  Make the other spine fold, and then the 1/4" fold from that line (toward the foredge).

Test fit the cover if cloth.  Clip off excess before gluing.  Put tattle tape onto spine cloth.  Glue up the boards, peel off the double-stick tape backing.  Press board going from spine to foredge.  Nip 30 seconds in press.  Let dry one hour under weight.

Prepare old case materials to reattach:

Trim out spine, old plate from old cover and reattach.  If the spine is porous, line the back with Japanese tissue.  If barcode is on board make sure to save and reattach.  If old cover is not usable in one piece, trim front and back covers to size and glue onto new cloth.

Once textblock is dry, trim no more than 1/16" from the head, tail and foredge on the guillotine.  Do a visual double check of margins to make sure where cutting is safe.

RECASE

Paperback cover:

Take a piece of Tyvek cut to H x [spine thickness + 2"] and glue over spine area of cover covering the 1/4" folds by 1/2" or so.

Clean the joint area.  Put tattle tape onto the spine of case.  Recase the book.  Trim if needed.

VARIATIONS

Kerfs (do before put on cloth liner)
On a very thick book, could put on a second liner and then make kerfs (saw marks) cut into the spine at an angle.  Could glue in some thick sewing thread, leaving them longer and then glue them down to the sides.

Written by Brian Markee.

Image Resolution and You

Picking your resolution is perhaps the most important decision you'll make when digitizing photos, artwork, or any other kind of image. But it can also be confusing if you're not familiar with these terms and their meanings. This is a simple primer to help you choose the right resolution for your needs.

The terms DPI and PPI are both shorthand units for measuring an image's resolution. DPI stands for "dots per inch" and PPI, "pixels per inch." This means that DPI is technically a term for a printed object's resolution while PPI describes an image displayed on a screen, but in common use they are essentially interchangeable.

The system that these measurements describe is called Raster, and it's by far the most common in a modern digital setting. A raster image is essentially a mosaic, collecting dots of color called pixels in a tiny square grid to produce an overall image. The more pixels per inch, the more detailed the image. Simple enough, right? For an easy example, here is the same image at three different standard resolutions: 600dpi, 300dpi, and 72dpi (click to see at full size)

You can always lower the resolution of an image, but it's impossible to raise it, except in a simple multiplying sense. This is why all digital images look blurry if you zoom in far enough. You're making the pixels bigger, but you aren't adding any new information to them.

Another factor you will want to consider is your display resolution. Modern high-definition TVs will often give you this basic measurement, and while computers have a greater variety of resolutions they will generally fall under a few typical values. 480p means a screen is 480 pixels wide, and is considered "standard" definition. 720p is, of course, 720 pixels wide, and marks the beginning of "HD" standards. 1080p is probably the most commonly used HD resolution, and the cutting-edge "4K" resolution is a convenient shorthand for screens 3,840 pixels wide. The screen resolution will determine how "large any given image looks at full-resolution on the screen. If you try to stretch a 480p wide image across 1080 pixels, it will look bad.

While the ideas surrounding pixel resolution, display resolution, and print resolution are quite complicated, they can still be understood easily with a few guidelines. For most purposes you can create images using 3 different resolutions:

600ppi is what we at the Dartmouth Digital Library Program use as the standard for high quality "master" images. Although many scanners can go higher, the size of the file becomes very unwieldy at that point. My advice is to always start at at least 600. Better to have a high-quality image and not need it than to need it and not have it.

300ppi is a common resolution for a high-quality print. Unlike looking at a screen where the resolution can be shrunk or blown up, a printer is rigidly limited in the amount of detail it can put into any given area. While a particularly good printer may get higher resolutions, most will clock in around 300dpi. This lower resolution also makes transferring files for print easier. And of course, it's always useful to keep your higher-res files around in case you need to go back to them.

72ppi has become the most common display resolution on the internet. There are a few things to consider before simply converting your image into 72ppi. Look at your display, and understand what its resolution is. Then consider how "big" you want your image to look on the display. So, if you have a 1080p monitor and want an image that fills the whole screen, you'll want to change your ppi to 72, AND change your image width to 1080p at the same time, with the proportions locked.

Here we can see Photoshop's image size menu (Image -> Image Size), where the pixel width and resolution are changed while the proportions remain constrained.

This is often a confusing concept to grasp. The simplest way I can think of is: if you reduce a 300ppi image to 150ppi, but also double its size, it will essentially be the same image when you see it on your computer. But if you try to print that, it will be half as detailed by virtue of being twice as big.

Fortunately, you don't need to fully understand all of this in order to create and work with high-quality images. As long as you make sure your highest-quality 600ppi master versions are safely backed up, you can play around with these variables in Photoshop or any other imaging program until you meet your own needs. Understanding how screen resolution, print resolution, and image resolution work together is an ongoing process that changes with technology as well as peoples' needs. It's important to be consistent, especially so for an institution like ours, but it's equally important to know how to adapt to your own needs.

Written by Ryland Ianelli

Conserving Collaborators: making it work.

Last October, I had the pleasure of having Giselle Simon, Head of Conservation at the University of Iowa, in the lab for a day.  Giselle and I go way way back so it was just like old times.  I thought "What could we do in a day?"  I recalled that Giselle had treated many antiphonals when she was the Conservator at the Newberry Library in Chicago.  And it just so happens that we have one here that is displayed in the reading room of Rauner Special Collections in need of assessment and attention.  So how perfect, with Giselle's help (which this was definitely a two person job) we transported the antiphonal down the long corridors and elevator rides to the conservation lab.

All tied up and ready to go.  Rauner Special Collections reading room.

Being able to maneuver the pathway was tricky.

Getting the book into the elevator.  Tight squeeze.

Riding solo going down, no people allowed.

Once off the elevator, transport got a bit easier as we had a truck to put the book on and wheel away.

The goals for the day were simple.  To assess the book, perform some minor stabilization, and create a carrying/support tray.

Giselle using a HEPA vacuum to clean soiled surface.

Once we got the book situated, we realized that the surface needed quite a bit of cleaning.  Surface debris was evident in a substantial amount of areas.  Giselle hopped right in and gave it a go with her gentle touch.

In the paste down area there was extra surface debris which she was able to clean.

The back board was damaged at the fore edge, missing the outer portion of the board.  This resulted in the pages bending at the fore edge because there was no support under them.  Therefore we came up with a quick solution for a moderate fix.  We cut a strip of matt board that fitted precisely into the missing area and pasted it down with a tissue strip placed in top for a bit of extra strength.

Piece of matt board secured to fore edge of lower board.

 The next step was to fabricate a carrying tray.  We didn't have all the materials to make one like the Newberry so we improvised.

Carrying tray at the Newberry.  Coroplast lined with Volara.

Newberry tray showing a catch wall at the back.

Nothing like getting out the glue gun.  I knew I had bought that for something!

Multiple layers of blue corrugated board were laminated together to make the tray, then we adhered a sheet of Volara.  We also had time to relax and flatten some of the pages.  So in a few hours a lot was accomplished.  The antiphonal was returned at the end of the day in much better shape than it had been.  Because of the detailed inspection and keen team work the next steps are within reach and a game plan is laid.  Sometimes, those seemingly overwhelming big jobs, just need that initial step, and having a conserving collaborator around can be just the thing.

I've always fantasied about a conservator exchange program, whereby we could visit each other's labs to help on a project, to share our experiences, and to learn new techniques and approaches.  A week would be great, but I'll take a day!  Thanks Giselle.

Giselle, settling in!

Written by Deborah Howe