Cast Composite Films

May 31, 2010

At the 2010 LCCDG, Grace Owen and Sarah Reidell, conservators at New York Public Library Goldsmith Conservation Lab, presented some preliminary results using cast composite films.  They are cast with acrylic gel mediums and paints on a silicone mold which replicates the grain of various leathers.  Surface casting techniques were borrowed from objects and painting conservation, and can be attached to a wide variety of substrates.

Grace showed me a couple of the samples she had prepared, and it seems to be a technique that could show great promise for board slotting.  Hopefully, they will present a paper on the subject when their experiments are completed. This seems to be a very exciting prospective treatment– the inherent strength of board slotting combined with visual integration of cast acrylics.  Stay tuned.


More on Syringes

May 26, 2010

I noticed that McMaster-Carr sells syringes and needles in the United States. They are currently  available in type 304 stainless steel. Gauge 25, .020″ O.D. fits a 1/64″ blade quite well, $13.97 for 50.  The 21 Gauge, .032″  O.D. fits the thicker 1/32″ blade, also $13.97 for 50.  Both are an easy to handle 1/2″ length.

As Victoria previously mentioned, there are advantage to flexible plastic needles as well.  The thinnest PTFE needle they sell is 22 Gauge, .040″ O.D., $19.43 for 10. They also have a Polypropylene needles, 25 Gauge with a .029″ O.D. for $2.23 each.

WARNING: Their catalog contains over 480,000 products and is highly addictive.


Visible Board Slotting

January 5, 2010

Recently, as I was installing a board slotting machine, several of us started talking about the possibility of slotting other materials.  The blades that the machine uses were originally designed to cut metal, and I’ve successfully slotted wood for an artist book edition. Plexiglas, aka. Perspex, was a natural choice, given its use in mounting applications The ability to insert an flexible hinge into a piece of it seemed to be potentially useful for something, although I’m not sure exactly what.  Normal plexiglas slotted fairly well, with a fairly even matt appearance in the actual slot, but cast plexiglas, which is optically slightly clearer, didn’t slot as evenly, and tended to clog in the slot itself.  Reversing the direction of the blade, in order to clear the slot, exasperated the problem even more.

I haven’t tried the new Optium (TM) from Tru Vue, which according to the manufacturer, has less than 1% reflection at a 90 degree viewing angle, dissipates 2000 times more static charge than normal acrylic, passes a 600 dry cloth rub test (at 2.5 pounds) for abrasion resistance, 99.6% UV filtering below 380 nm and 98% light transmission.  At least they send out an impressive looking sample set!

Since the exact path of the blade is visible, a slotted piece of plexi is a useful teaching tool when beginning to learn board slotting.  It helps the uninitiated visualize where to begin the slot relative to the height of the board.  The dust tended to clump together, so a thin, rigid piece of paper was used to clear the slot.

If nothing else, this visible slot is a very clear example of the precision and angle that is usually hidden.


Daubeny Project: Light Relief

November 19, 2009

The last few weeks has seen me concentrating on the big questions of light and consolidation.

The Daubeny Library both benefits and suffers from being in its original laboratory setting. The context is wonderful and really adds to the uniqueness of the collection, but the light exposure it suffers from several 3 metre+ high windows which face the book presses is less great. I have been logging light levels over a number of months, as well as setting up a long term light test using samples of the dyed textile used for slotting. Light levels have become somewhat of an obsession due to the work I did on the reactive dyes, as traditionally, and somewhat unfairly, they have always had a reputation of being less light fast than direct dyes. At Daubeny, the UV light levels are encouraging but the visible light levels are slightly too high. It is a difficult space to regulate in light terms as it is used both as a library and a lecture room. Consequently I have been encouraging users to lower the blinds in the room after use, but this has had a variable degree of success. However, any lowering of light levels is a big improvement on the relatively uncontrolled exposure the collection has experienced up until the recent refurbishment of the laboratory.

Consolidation in progress. Image reproduced with the kind permission of the President and Fellows of Magdalen College, Oxford.

The chemically degraded nature of the majority of the leather covering the Daubeny books has also been a challenge. Early tests with the traditional consolidant mixture of klucel g in IMS showed considerable and unacceptable darkening of the leather, and a coarsening of the leather surface. Having done some research into the water content of common solvents, I settled on isopropanol as the solvent of choice. Unlike IMS, with a water content of up to 1%, isopropanol has a water content of less than 1%, and as such seemed a better bet not to darken the leather. I made a 2% solution in isopropanol by gradually adding the solvent to the klucel g, stirring all the time, and leaving it to fully dissolve overnight. This resulted in a very smooth, gelatinous liquid which when applied with a brush caused neither darkening nor streaks across the leather surface.

Victoria (Stevens)

The experiments on the dyeing of spine materials for the Daubeny slotting programme has taken up my time and almost all my thought since my last post on this project.  This is due to it being uncharted waters for me and the criteria being fairly demanding.  I needed a process that was simple and could be achieved in a normal studio setting with the equipment available, and which provided a strong depth of shade using a dye recipe that was easy to accurately replicate.  As the Daubeny books are stored on open shelving good light fastness was also important.  Finally, I did not want a dye which altered the texture or handling properties of the aerocotton chosen for the new spine material.

This search for the holy grail of toning and dyestuffs was quickly narrowed down to 2 dye systems: direct and reactive dyes.  Direct dyes, specifically the Ciba-Geigy direct dye Solophenyl, are used extensively by textile conservators.  They have excellent reproducibility and light fastness but their relatively low wet fastness is an issue.  They also require heat and pH monitoring during the dye cycle leading to a reasonably elaborate procedure.

Reactive dyes, such as Procion MX and Cibaron, or its new incarnation Novacron, are highly solvent resistant due to the strong covalent bond they form between the dye and the fibre.  The dye cycle does not necessarily require heat as the dye is extremely reactive under normal ambient conditions.  This category of dyes have fair to very good light fastness, with the reds being the poorest.  However, this is so with all dyes types.  On the negative side, the highly reactive nature of the dyes can make them difficult to reproduce accurately and can cause unevenness in colour, or unlevellness, across the textile.

Having worked with collections stored in historic buildings I was all too aware of the water based events that can occur involving library and archive materials.  Also, having attended a course on dyeing, arranged by the Textile Group of Icon at the much mourned Textile Conservation Centre (TCC), and witnessed first hand the relatively complicated procedure involved in using direct dyes, I knew reactive dyes were the way forward.

My early results with Procion MX dyes have been very encouraging.  I have benefited from the advice and expertise of Stuart Smethurst at Kemtex, a UK distributor of these dyes, my colleagues at the Oxford Conservation Consortium and the Bodleian, and the mass of literature available on the subject.  I have listed supplier’s information and a brief sample of essential reading for anyone embarking on a reactive dyeing programme below.  These sources also detail recommended dye colours and the dye cycle very clearly, so I will not repeat it here.  However, the problems I had with levellness and reproduction of an exact shade may be avoided by taking care in the following areas:

1. Wetting out: it is important that the fabric is thoroughly wetted before making contact with the dye bath to ensure even uptake into the fibre.

2. The thorough mixing of the salt in the dye solution is also crucial.  The sodium sulphate used is very reluctant to dissolve, and the course information from the TCC recommends making a strong solution of the salt and adding that the dye bath, rather than trying to dissolve it in the bath itself.

3. Agitation: you can not rock the dye bath to much!

4. Rinsing and drying: the smallest amount of residual dye can cause unlevellness, so thorough rinsing in hot water to include a brisk boil wash for around 5 minutes is also important to achieve even dyeing.

With regard to light fastness, the 3 colours I am using have fairly good to very good light fastness.  I have set up light tests on my samples and will report in due course.  Finally, with regards to the inconsistencies in colour reproduction, I am looking into more accurate methods of measuring.  The quantities of dye in solution are so small that even minor discrepancies may cause differences in colour when a recipe is repeated.  A more accurate pipette has been ordered so hopefully this will result in more accurate colour reproduction from the ratios of the stock colours than I have so far been able to produce.  I’ll let you know how I get on.

Toning cloth for boardslotting using Procion MX dyes. Reproduced with the kind permission of the President and Fellows of Magdalen College, Oxford.

Sources of information and suppliers:

Ruth Norton, Dyeing Cellulose-fibre Paper with Fibre Reactive Dyes, The Paper Conservator, Vol 26 2002

Edward Simpson, Dyeing Aerolinen and Aerocotton with Reactive Dyes, Paper Conservation News 71, September 1994

Dyeing Techniques Manual, Textile Conservation Centre, 2008

Timar-Balazsy and Eastrop, Chemical Principles of Textile Conservation, Butterworth Heinemann, 1998

Lerber, Karin von, Cibaron F (reactive dyes) versus Solophenyl (direct dye) for Support Fabrics in Textile Conservation, Newsletter, ICOM Committee for Conservation, 1/96, 3-5

Stuart Smethurst, Kemtex Educational Supplies, Chorley Business and Technology Centre, Euxton Lane Chorley, Lancs, UK, PR7  6TE., 01257 230220.  Suppliers of dyes and auxiliary chemicals.

Victoria Stevens

Sometimes, a board to be slotted is slightly longer than the maximum allowed by the carriage.  It is still possible to slot these, and the example below illustrates the temporary modifications to the machine and outlines the technique.  In this case, board slotting was used on a small edition of 12 books.  The large (46 x 31 cm) medium density fiberboard covers were covered with burl veneer, and the artist, Accra Shepp, and I decided that slotting would be an ideal method of firmly attaching the laminated paper/ linen spine to to heavy boards, while keeping their clean, unobstructed visual appeal.  More information about the book including images is available at my blog.


First the clamping bar is removed and a four cm. thick plywood spacer is added so that the boards will clear the edge of the carriage.  In this case, 2 clamps proved adequate to keep the MDF from shifting during the slotting process.  For typical binders board, it may be necessary to clamp it between plywood during the slotting.



As the slotting progress, the clamps are moved so they do not hit the blade guards.  As long as only one clamp was moved at a time, the position of the board did not shift.  The MDF was very easy to slot.



Once the left side of the carriage cleared the motor, the board was clamped on the on left side.  It is necessary to turn the machine on and off a number of times to adjust the clamps– it would be dangerous to leave the blade spinning when adjusting the clamps.



When the machine reached the end of the available space, the carriage was brought back to the center of the machine.  If you look at the position of the board relative to the plywood spacers you will notice that the board has been shifted about 5 cm to the left, then reclamped.    In this case, it was necessary to release both clamps, and slide the board to the left so that the right side of it could be slotted.  Depending on how exactly the board is repositioned at the front of the machine, it may be necessary to readjust the height of the blade to reenter the exact position of the previous cut.



Once again, the clamps are moved and pictured here the board is finished being completely slotted.  If a number of oversize boards were to be slotted, it might be prudent to glue the stacked plywood together, so that they don’t shift, or even attach them to the base in the pre threaded 1/4″/ 20 tpi holes for the original clamping bar.  The book board itself could be clamped in a simple press (two pieces of plywood with 4 carriage bolts at the corners) to eliminate some of the shifting of the various components that I encountered.  This would make the repositioning of the board much easier and more accurate.


After a long run in due to pressures of other work, the slotting project at the Daubeny Library, Magdalen College, Oxford, is now underway.  A preliminary selection survey showed that the books were mostly of a similar level of deterioration, giving a wide choice of suitable material, and thankfully of a broadly similar colour.  This will mean that time spent dyeing will be reduced and so more books can be repaired in the time available.

Charles Daubeny, under copyright of and reproduced by kind permission of the President and Fellows of Magdalen College, Oxford

I have selected in particular a very large folio volume to work on, as up until now I have only ever slotted small octavo sized volumes with relatively thin boards.  It will be interesting to see how the slotting process differs on a large book.  Slotting this book is further complicated by the method in which it was originally bound.  The text block is made up of single sheets whip stitched or over stitched together in a very impressive display of chunky sewing.  This may create problems when attempting to attach the first slotted lining by sewing, which will definitely be required given the size of the book.

The next area to look at is dyeing the aerocotton.  I have decided to go down the Procion MX route, and any advice and help that anyone can provide on this dyeing method would be very gratefully received.

Victoria Stevens