Ultrasonic Misting- Part One

I’ve been busy the past several months in the Paper Lab getting together the parts, purchase requests and wherewithal to construct an ultrasonic mister in order to care for a group of paintings needing some attention.

Last year, Lilly Library received a generous gift of over 450 paintings by the playwright, screenwriter and producer Clifford Odets http://www.indiana.edu/~liblilly/blog/new-donation-the-artwork-of-clifford-odets/

Soon after the library received this gift, the Paper Lab hinged and matted nearly all of the paintings for storage and safer handling and access. During this process we noticed that a number of the artworks were suffering from condition issues related to the paint media that Odets chose. Much of the work relies on a layering method of drawing and painting over wax crayon. Odets would scratch through the pastel and gouache paints he favored to reveal the crayon beneath (a.k.a. sgraffito).

Here is a photograph of one such painting- on the back of a postcard- in raking light.

You can see how the teal blue paint has been scratched away to reveal orange, pink and purple wax crayon beneath. However, though the technique allowed Odets to create some wonderful images, it also created what we conservators refer to as inherent vice. There is little adhesion between the media layers and as the upper water-based paint layers dried, they began to shrink in place causing minute cracks and more seriously, flaking and loss. This close-up shows what I mean (poor little flaky fish!)

 

In these circumstances, conservators perform a process called consolidationTypically, the consolidant is a type of adhesive carefully chosen for a number of factors including, but not limited to, compatibility with the object physically, visually and chemically, ease of preparation, ease of application, quality of bond strength and ageing characteristics. Normally, the process would be carried out under a low-power microscope using a small brush and delicately applying the consolidant to the cracks and underneath the lifting paint, fastening it back down. With these paintings the scale of damage prohibits such an approach- the fish above is 2cm long, which makes each of the tiny flakes far smaller than a millimeter in dimension. My fine motor skills are excellent, but not that excellent!

Another method is called for: that of Ultrasonic Misting. Developed by the Canadian Conservation Institute in 1990, the ultrasonic mister allows greater control of the whole process of consolidation of powdery paint and pigments. Unfortunately one can’t readily buy such systems- at least not at affordable rates for an aerosol generator- so I set out to construct one myself. There are a number of published articles explaining how to make one as well as a number of institutions who have blogged about it in the past, such as this account from the UCLA/Getty Conservation Program. Within a month or so I had purchased and cannibalized the necessary parts and had it up and running:

What the device consists of is a domestic ultrasonic humidifier, with the upper water reservoir removed. We use this very humidifier routinely in the lab for the relaxation of library materials, so it was good to have on hand! Resting in about one inch of water over the oscillator within the humidifier is a LDPE plastic bottle containing the consolidant adhesive. Ultrasonic frequencies generated in the base of the humidifier travel through the bottle and cause cavitation to occur, generating a fine mist of adhesive to rise from the liquid. A pump (the large white cube in the background to the left) was borrowed from our vacuum suction table to drive air into the bottle (through the clear tube entering the back of the bottle), and then the adhesive-laden water vapor finds its way out the top, through another length of tube to be emitted through a small applicator nozzle. Also sitting in front of the device is the consolidant of choice. Can you guess what it is? There is a clue in the painting I chose to include earlier…

Next week, I’ll cover the pros and cons of the design and talk about the success of the treatments.

Preservation Week 2015

custom made enclosure
custom made enclosure

Next week marks the fifth occurrence of annual ALA-ALCTS Preservation Week events.  To borrow from their website :

Preservation Week was created in 2010 because some 630 million items in collecting institutions require immediate attention and care. Eighty percent of these institutions have no paid staff assigned responsibility for collections care; 22 percent have no collections care personnel at all. Some 2.6 billion items are not protected by an emergency plan. As natural disasters of recent years have taught us, these resources are in jeopardy should a disaster strike. Personal, family, and community collections are equally at risk.

Recognizing this need, ALA and its Association for Library Collections and Technical Services inaugurated national collections Preservation Week, May 9-15, 2010, along with national partners that include the Library of Congress, Institute of Library and Museum Services, American Institute for Conservation, Society of American Archivists, and Heritage Preservation

ALA and its partners urge libraries, museums, and archives to take this week to remind others of the importance preservation efforts play in maintaining our collective national heritage and accumulated knowledge in the form of the written and printed word.

We don’t have any special events planned this year as last, but that doesn’t mean  preservation efforts have stopped in the lab. In fact, we’re working harder than ever to identify, prioritize and care for those very types of items mentioned above, within IU Bloomington Libraries and other Bloomington Campus collections.

Fiscal year 2013-2014 saw 6,736 enclosures made for items as varied as wooden puzzles, microfiche rolls, artist books, manuscripts, scrapbooks, photographs, pamphlets and just about any other category of item in our Special and General collections. 3,056 individual items were given remedial care. 6,603 volumes were prepared and sent for commercial binding.

Beyond this, Preservation staff are on call to respond to water emergencies affecting collections across campus. We provide insect and mold remediation services to many research centers and departments. Tours of our facility are conducted on a regular basis educating students, staff, faculty, donors, peers and university presidents about the work we do; spreading the importance of our mission.  Seven temporary/student workers are currently employed and provided with valuable on-the-job experience in the Library field as well as income to aid in continuing their studies.

All told, much of the work we do has a visible effect on collections- items are repaired and made available to circulate safely and enclosures are created to aid in best storage practice. Beyond that, Preservation plays an integral part in library operations as a partner in the overall mission of providing the University community with information resources for years to come.

Transportation

The Preservation Lab at IU Bloomington shares the same address as our Auxiliary Library Facility (ALF)- a compact storage facility on the edge of campus designed to hold 6 million book volume equivalents. Most of the time, we enjoy being away from the parking hassles and student congestion of the main campus libraries, but increasingly we’re finding issues are cropping up with transportation of collection materials. ALF currently stores 3.2 million books, manuscripts, maps, architectural plans, film reels: you name it! Combine this with transport needs for the items we’re working on in the Paper Lab and General Collections Lab and quite a lot goes back and forth each day.

Much of the work the Paper Lab handles is transported using personal vehicles, for a number of reasons:

  • It’s often easier and quicker to just do it yourself.
  • I can be available to consult with subject librarians and archivists if they deliver items in person.
  • Flat paper items often do not fit into the totes utilized for book delivery.
  • I get a chance to visit satellite libraries and reinforce professional relationships.
  • I can rule-out mishandling of items during transit.

However, recent developments are causing us to reassess some of these habits. Our Geosciences Library closed, with much of the collection coming out to ALF. I’ve also implemented a rolled-storage method of housing campus architectural plans out here (representing a significant portion of the University Archives holdings). Additional pressures have arisen to store items from other campus entities that don’t always fit the mold of tote-able goods. There are also liability issues with the transport of university property in personal vehicles. All of this means that more and more requests are coming in for items whose transport needs haven’t been formally considered.

ALF employees currently make a five mile round trip once a day to deliver requested items to patrons at campus library locations. A second trip to the main library (Wells Library) occurs too. Books are packed onto shelved A-frame style carts and strapped to the walls of a box truck. There is also a separate Library-wide mail service originating at Wells; rigid plastic totes are used by this unit. In order for oversized materials (either on a rigid tube, or foldered/flat boxed) to be transported by either service, they must be packed securely and robustly, strapped down when appropriate, be weatherproof and capable of delivery by one person. Packing must also be straightforward on both the shipping and receiving end for conservator and general library employee alike.

So, after some searching for products to meet these specifications, we’re going to pilot two types of cases: a rigid tube and a reinforced case.

 

tube

case

The interiors of both cases can be filled out with Plastazote and/or Volara foam for clean, discrete and archival padding. Existing delivery routes and workflows should not need to be changed. I forsee some training needed by those who manage collections and staff reading rooms, but nothing that an instructional session and some printed guidelines can’t solve.

Mass Humidification

We mentioned a month or two ago a long-term project we have going with the Wylie House on campus. Roughly 5000 letters of correspondence are being cleaned, repaired and rehoused for eventual storage at ALF– the compact off-site storage facility our library system has on campus. Surface cleaning and mending the letters has been relatively trouble free, but early on we realized that the stage of humidification (prior to pressing) was causing a workflow log jam. The first efforts involved utilizing the dome on our cold suction table. An ultrasonic humidifier feeds humidified air into the chamber and after a couple of hours, the letters are damp and ready for pressing.

We could only humidify about twelve to fifteen leaves at a go with this method, so we added on another humidification technique by turning our large sink into a chamber, supplied with wet blotters beneath a layer of Gore-Tex. Another dozen or so letters could be prepped this way each day.

sink humidification

Even with these two options, pressing efforts were being stalled, causing us to go back to our client library with a much longer than originally projected completion date. Thankfully, inspiration struck and it occurred to us that it may be possible to convert our print drying rack into a Mass Humidification Device.

drying rackWe constructed a slip cover of sorts out of plastic sheeting and Velcro tape that fully encloses the rack, except for the bottom. With a generous ‘dust ruffle’ of sheeting at the base, not much water vapor seems to leak out. The cover is constructed of two parts: the larger is a single sheet, with stapled ‘seams’ giving some rigidity to five ‘panels’ to wrap around the rack, with closure in the front; the second piece is a top that Velcro bonds to this upright portion.mass humid test1

The above photo shows initial tests introducing humidity into the chamber by way of the ultrasonic option. After several hours, the %RH was only up to ~70%. Opening up the cover revealed that the humid air wasn’t dissipating into the overall volume fast enough, before condensation occurred at the point of introduction. In other words, we had liquid water and dripping where the hose made contact with one of the shelves, but dryness elsewhere. A second set of tests with wet blotters proved much more effective with speed of humidification and distribution of water vapor.

We are now able to fill 20-25 shelves with correspondence per day. A wet blotter is placed between every 4-5 shelves of letters. Humidification takes place over about six hours. We empty the rack of its contents at the end of the day, and create a press stack for overnight drying and flattening.  The process is repeated the next day, ensuring that items are pressed for 24 hours, which is effective enough for single-leaved, stationery-weight paper.  Foldering and boxing then occurs.

papers on rackpressing stack

-submitted by Doug Sanders

 

Craig Lab Quarterly Report (July – September 2011)

In spite of having nearly no student employees in any of the Preservation units during this period, our output for the quarter increased for both the General Collections Conservation and Kasemake units while both the Paper Lab and Bindery Prep saw slight decreases that are typical of the summer.

In the General Collections Conservation unit total treatments increased from 2,407 during the previous reporting period to 2,615 for this one. Of these, the higher level treatments declined while enclosures nearly doubled as staff spent considerable amount of time working on projects for the Fine Arts Library.

Continue reading “Craig Lab Quarterly Report (July – September 2011)”