Reproduced by permission of the author - Ron Flynn
| Matting and Framing |
A Modern Guide to Archival Museum Quality Matting and Framing For Your Audubon Prints
When hiring a frame shop to mat and frame your Audubon prints, the words "museum quality", "conservation" and "archival" will be terms you will hear often in connection with materials and techniques. You might naturally think that the term “museum quality” means better or a higher standard, and that “conservation” and “archival” mean longer lasting or preserving. Unfortunately, there are no agreed upon industry standards that define these terms, or guarantee the quality of materials used and/or the work done. Rather, these terms are used by the manufacturers and framers to describe the many different products and techniques they use in matting and framing. The purpose of this chapter is to point out the differences in these products. This will help you decide which matting and framing products and techniques are right for your particular prints, in the location and environment where they will be displayed. You will need to weigh the monetary or sentimental value of your prints, against the costs of using different framing and matting materials and techniques, to achieve the overall appearance you desire with the appropriate level of protection for your artwork.
My wife has been a watercolor artist for a number of years, and I have been collecting and selling antique prints for many years. We have a considerable amount of matting and framing work done. We do no matting and framing ourselves, but are fortunate to have access to private framers. I regularly confer with our framers, and the curator at the local college museum, about the latest materials, techniques and thinking in the areas of archival museum quality matting and framing.
Generally, it is recommended that your artwork be hung in areas with relatively constant temperatures, and away from excessive heat and humidity. Sunlight, halogen spotlights, black light, and direct indoor incandescent and florescent lighting can all fade colors, darken unpainted paper surfaces, and contribute to the deterioration of the artwork over time.
The basic purposes for matting and framing are to display your artwork in a way that will best enhance and highlight the beauty of the art itself, plus encasing it in a protective stable environment that will greatly lessen the potential for damage and deterioration from interior and outside sources, and prolong the life of the artwork. When matting and framing your Audubon prints, there are 3 main areas of consideration: the glazing, the frame, and the matting package. There are a few other items to think about, which I will also discuss below.
GLAZING
Glass -
Glass, of course, will protect your artwork from airborne dirt and pollutants, especially in areas where smoking is prevalent. It also affords some protection against damage from little flying objects that children might throw around. Finally, glazing prevents very interested or curious people from actually touching your artwork and leaving finger smudges or natural human body oil residue from their fingers.
Regular picture framing glass (perhaps under different names regionally) is the most common material used for glazing. In quality, it is a step above ordinary window glass that you might buy at your local hardware store. Picture framing glass can come in different qualities from different manufacturers. At a minimum, picture framing glass should be clear and without imperfections. Popular back in the 1960s-1980s and now experiencing a comeback, non-glare forms of regular picture framing glass are available. Non-glare glass has been lightly sandblasted or etched on one side. This cuts down on the reflection of light when artwork is viewed from different positions. Avoid textured or etched non-glare glass. Acid residue could remain which has not been completely neutralized. Also, some non-glare glass will not be as clear, and will slightly distort the details in the artwork or change the colors of the artwork underneath it. If you are thinking about using non-glare glass, be sure and view your artwork (in natural and artificial light) under a sample of the glass. Borrow a few of the frame shop’s mat board corner samples and set them between your artwork and the glass. You’ll then see your artwork, through the glass, at the same spacing as it would be when matted and framed. This is important! If your artwork does not have a relatively high sentimental or monetary value, you could safely use regular picture glass (clear or non-glare) if your artwork is hung in places where only reflected or ambient light reaches it.
Conservation Glass -
Obviously, you want your artwork displayed in an area with enough light so it can clearly and comfortably be viewed. Too much light, however, will cause damage to your artwork over time. Quality frame shops will now likely suggest that you use conservation glass for all your artwork. Conservation glass (sometimes referred to as UV glass) will filter out various levels of the damaging ultra-violet light rays from the sun and from fluorescent and other artificial light sources. However, UV glass does not prevent damage from visible light sources. Apogee Enterprises Inc. produces a wide range of glass and acrylic products under the Tru Vue trademark name. Tru Vue has virtually become a generic term in speaking about glazing for framing. Other companies have come out with similar products using slightly different spellings of the Tru Vue name.
There are 2 important characteristics that you should consider, against the cost of the glass and the value of your artwork, when choosing conservation glass. The most important is the percentage (%) of UV light that the glass blocks. The second consideration is the percentage (%) of transmitted light that the glass does not block, and therefore allows your artwork to be seen in its best light. In both cases, the higher the percentage the better.
Conservation glass is available in both clear and non-glare forms. Always bring your artwork to the frame shop to see how it will look under non-glare glass, if you are considering using it. Depending on the individual manufacturer of the glass, there may be one to several different conservation glasses available, with different specifications. Its costs will range from 2-3 times more expensive than the best picture framing glass. Today, it is probably a good idea to at least use a conservation glass with all your Audubon prints. You should find out what percent of the light in the UV spectrum is filtered out by a particular glass. Conservation glass will generally filter out 85% - 95% of UV light.
Museum Quality Glass -
I think it would be fair to say that any museum would utilize the highest standards and very best materials in protecting and displaying their artwork. Again, there are no agreed upon standards for a “museum quality glass.” Some UV glass is also called museum quality. However, a true museum quality glass will cost considerably more than any other previously mentioned glass, and will exhibit superior qualities and features.
A good museum quality glass would offer non-glare features to eliminate reflections from your artwork when viewed from different angles. Yet, this glass would be smooth and hard, to reduce excess collection of airborne dust and dirt. It might also have an anti-static coating. A good museum quality glass would be harder and stronger than other picture framing glass, but it would be optically clear and distortion free, allowing 96% - 98% light transmission through it. Finally, a good museum quality glass should offer filtering of 98% - 99% of the radiation from the ultra-violet light spectrum.
Below is a list of the costs I found for an 8” x 10” piece of the various listed glass products –
Window glass $1.25
Picture framing glass $3.00
Tru Vue Conservation Clear $6.00
Tru Vue non-glare Conservation $11.00
Tru Vue Best Museum Glass $47.00 (this is NOT a typo)
Acrylics –
Clear acrylic sheets (Lucite®, Plexiglas®, and Lexan®) are materials that are being used more and more today as quality glazing materials in archival matting and framing. Acrylic sheets are perfectly safe for your Audubon prints, but they can develop static charges and may not be safe for other artwork such as chalk and pastels. Their chief advantages over glass are their nearly unbreakable characteristics and their lighter weight. They should be considered for any size artwork that will be hung in a rec room or children’s room where balls or other objects might be tossed about. When matting and framing double elephant sized Audubon prints, whether original or modern reproductions, acrylics might be used in place of glass to reduce the overall weight of the finished framing job.
Acrylics cost a bit more than regular picture glass. It can be considered archival because it is stable and does not out-gas any fumes that would harm your prints. Acrylics are optically very clear and distortion free, and come in several thicknesses. However, acrylic sheets can show up with minute scratches in them. Do not hesitate to reject a sheet with scratches. If the scratches are miniscule and in an area over the window mat, they will be virtually invisible if placed on the inside, up against the window mat. Acrylics are available with a UV coating that will filter 95-99% of ultra-violet light. They are also available now in non-glare forms. While certainly not traditional, acrylic sheets have legitimate uses in modern matting and framing, and are now being used more often.
Antique Glass –
Framing with original antique glass is becoming more popular. Individuals or frame shops will rummage through salvage yards where fixtures and furnishings from old buildings and homes are sold. Often, old windows or individual glass panes can be purchased at fairly reasonable prices. This 75-100 or more year old glass will give some authenticity to framing an antique print. The imperfections and other marks commonly found in glass of that age would give it some original character. The glass can be cleaned up and cut to size, often trimming off the edges where glazing putty has stained it for many years. Some frame shops can arrange to have a clear UV coating applied to this glass to further protect your artwork.
No Glass –
One of the newest ideas in framing is to frame a print without using a glazing covering. Using blind archival fastening, the print would be mounted to a back mat or board, and framed without a top mat, as if it were an oil painting. This technique would not yet be recommended for antique Audubon prints. However, it is something to consider when framing modern high quality Audubon reproductions.
There is a relatively new product called Print Guard, manufactured by Lyson Inc. in Illinois. It is recommended for use on any watercolor or water-soluble surfaced print. It comes as an aerosol spray, and 3 light coats are applied to each print. The flat non-glossy finish provides protection from moisture and humidity. The print can be dusted or lightly scrubbed to remove dirt and fingerprints. The most important feature of this coating is that it filters out 97-99% of ultra-violet light.
I have treated 2 later edition Audubon octavo bird prints, and another 12 assorted modern prints, with this product. All are framed, without glazing, and are hanging on a wall that is bathed with direct morning sunlight, plus they receive several hours of overhead incandescent lighting each day. I have control samples of all prints stored in my paper vault. Upon comparison after more than 3 years, there is no noticeable fading of colors, or darkening of any of the uncolored paper areas, from either of the light sources.
FRAMES
Frames for your Audubon prints can be made from many different materials. Wood is, of course, the most popular material. Frames are also made from metal, glass and plastic. I will not discuss glass or plastic frames because they are either, in my opinion, inappropriate or not structurally sound. There are hundreds of metal frames available that might be used in particular decorating schemes. Metal frames are mostly extruded in very simple profiles and designs. There are a few ornamental cast metal frames also available. Metal frames come in various natural metal finishes, as well as painted colored finishes. Metal frames are structurally stronger than wood frames. Therefore, a smaller width metal frame will safely hold and support a larger and heavier sized framing job, compared to an equally sized wood frame.
Wood Frames –
There are thousands of different wood frames available in various profiles and finishes. This chapter is not intended to favor particular frame finishes or profiles. The selection is vast and the final decision is up to you, and your particular taste and decorating scheme.
Wooden frames, and some simple metal frames for that matter, are available in standard sizes at Wal-Mart and other major discount store outlets. Some of these frames are made of solid woods, like oak, and are adequate, but often the assembly is not precise and professional looking.
In terms of quality, the next step up from pre-manufactured standard sized frames from retail outlets is the so-called custom frame. The term custom frame or custom framing has many meanings. You can find, on the Internet, many companies selling a vast selection of “custom frames” at “discount prices.” While the profile selection and variety of finishes is generally fairly large, and certainly more than your local Wal-Mart, they are usually made from inexpensive woods, or other wood materials, and come in standard sizes only. A few of the Internet custom frame shops will allow you to provide your own measurements, and they will manufacture a custom sized frame for you. The cost will be somewhat higher than their standard size custom frames. You should again take note of the materials used and the quality of workmanship in the finished product. Most of the Internet custom frames are a bit better than what you might find at a Wal-Mart or similar store, but local frame shops can do much better in terms of quality and service.
Custom Frame Shops –
When you walk into your local framing shop, with the idea of matting and framing one or more of your Audubon prints, you should get the impression that you are dealing with professional competent people, who have knowledge of the latest materials and techniques of archival museum quality matting and framing. When you go, bring your artwork and all your questions. You should expect individual and personal attention, specific to your needs. You may want to call first and ask some of your more important questions. Maybe you’ll discover that a particular frame shop is not equipped or knowledgeable enough to suit you. If you phone first and tell them what you want done, you might make an appointment with the owner/manager or person most knowledgeable about your area of matting and framing.
At a frame shop, you will likely see scores or hundreds of pre-finished frame samples from a number of manufacturers. Some samples may come in various colors, but not all will be displayed. If you find a profile you like, ask what finishes it comes in. Pre-finished frame mouldings are usually sold by the foot, and each side of a frame is measured from point to point to get the total number of feet needed for a frame. Prices will vary widely. I’ve seen pre-finished wood frame mouldings from a company like FrameAmerica at less than $5.00/foot, and mouldings for over $30.00/foot for some Larson Juhl frames.
Once you have selected your frame, glazing and matting (discussed next), the frame shop will do one of two things. Most frame shops do not actually make your frame in their shop, for lack of space, or lack of money for a large moulding inventory. Instead, they will phone in your frame’s manufacturer name, style and measurements, to a regional manufacturing warehouse. The warehouse will cut and assemble your wood frame and ship it to the frame shop. Some of these manufacturing warehouses are near enough to the frame shop so that someone can make regular trips to pickup assembled frames and other matting and framing supplies as needed.
Some frame shops will have the inventory and equipment to actually assemble your frame at their store. No matter who assembles your frame, it is the quality of the work that matters. Look around the frame shop. They will likely have framed art or prints for sale, or have framed work there that is waiting to be picked up. Examine the quality of the workmanship. Look at all four corners and see how they line up. Whether you pay $5.00/foot or $30.00/foot for your frame, you do not have a quality frame job if the corners aren’t well constructed. This is an easy way to evaluate the work done by a particular frame shop.
Whether you choose an authentic antique frame reproduction, or choose a period, contemporary or modern design, the choice of frame finish and profile is yours to make from the hundreds that are available. Finally, your frame shop should advise you on frame size and structural stability. If you are framing a full double elephant sized Audubon print using a metal frame, with either glass or acrylics, a 1” to 1-1/2” wide metal frame should be structurally sufficient. If framing the same print with a wood frame and acrylics, a 1-1/2” to 2” wide wood frame should be adequate. For a wood frame with glass, probably a minimum 2” wide frame should be used to carry the weight and maintain structural integrity.
Custom Wood Frames –
If you want the very best of frames, you can have a truly custom frame built for your artwork. You will find these custom frames available at large or exclusive print dealers, highly specialized frame shops, and at upscale art galleries. A truly spectacular authentic custom frame, along with hand colored mat, and museum quality glass, might cost in the $1000.00-$25000.00 range for a double elephant sized print.
This type pf frame is assembled from unfinished hardwood mouldings. The mouldings can be ornate designs made by machine, or can be hand carved. Once assembled to the correct size for your artwork, they are sanded to perfection, and then finally finished. How your custom built frame is finished can almost be left to your imagination. However, many examples of authentic period frame finishing designs will be available. You could easily take features from more than one example, and combine them into your personal custom frame.
Simple yet elegant hand rubbed wood finishes, in most any shade you want, are available on a large variety of different woods. Custom colored hand painted features and accents can be added. Various complementary or contrasting wood inlays can be included. Gold-leaf and white gold-leaf accents can be added. For an authentic yet completely different look, the unfinished frame is covered with gesso (a plaster like coating), followed by a smooth clay layer in one of several colors. Gold-leaf is then applied to the colored clay layer, and burnished by hand (a very laborious process). The burnishing of the gold-leaf gives the gold its luster. Further hand burnishing removes minute areas of the gold-leaf, revealing portions of the colored clay beneath it. This produces a very stunning and dramatic effect. To complete these unique custom frames, additional hand antiquing and distressing provide the final touches.
Wood Out-gassing or Leeching –
There is the potential for out-gassing, or leeching out, of harmful fumes or by-products from some wood frames. In certain unseasoned or inexpensive wood frame mouldings, resins or other acidic chemical compounds may exist in the wood. These acidic compounds or resins, or fumes from them, could actually come out of the wood mouldings and get into the mat package and damage the matting materials or even the artwork
All surfaces of pre-finished frame mouldings are generally finished and sealed, except for the rabbet. The rabbet is the right-angled cutout in all wood frame mouldings that accepts and holds the glazing, matting (with artwork) and any support backing. A frame rabbet usually comes as freshly cut unsealed raw wood. Conservationists now recommend that the right-angled rabbet of any wood frame be sealed with either a clear acrylic sealer or a polyester tape with acrylic adhesive, before assembling the entire frame package.
MATTING
I’ve discussed the frame and the glazing. The rest of the materials that go into a framing job are referred to as the “framing package”, “mat package” or simply the “package.” A few people might include the glazing as part of the “package”, and I won’t quibble.
The most important parts of the package are the window or top mat and the back mat. Besides hinges and fastening devices, the window and back mats come in direct contact with your artwork, and therefore must be made of materials that will not damage your artwork. Unless your artwork is fairly small, you will undoubtedly need a backboard or backer board, which goes behind the back mat, to help support and give structural integrity to the package. Finally, a moisture barrier and dust cover would complete the package.
Mat Board Composition and Construction –
The window mat and the back mat would generally be made from the same mat board material. The window mat is, of course, the one on top with the beveled cutout to reveal and display your artwork. Only about 1/4” of the window mat, along all four edges, need contact the artwork to hold it down. However, some Audubon prints and modern reproductions are done on large paper sheets with smaller image areas. In these cases, a larger area of the window mat will cover and contact the artwork. The artwork is attached to, and rests entirely on, the back mat. Mat boards are a pressed board made of fibers. They generally come in various thicknesses called plies. Commonly, mat boards are sold in 2, 3, 4, 6, and 8 ply thicknesses. 3 and 4 ply are the most commonly used. 2 ply is more for photographs and very small artwork. The thicker 6 and 8 ply are used for their added strength to very large mats, or where special effects such as added depth are required. Added depth can also be achieved by double or triple matting.
There are many different kinds or grades of mat board. Some are not acceptable for archival museum quality matting, despite what is claimed. Read the specs before you decide which one to use.
Standard mat board is made from bleached wood pulp. It is not acid-free. Lignin, and other chemicals from the wood pulp in the mat board, will soon turn a standard mat yellow or brown, and turn any artwork it touches acidic. When this happens the artwork will discolor and begin to deteriorate. Standard mat board is NOT RECOMMENDED.
Buffered mat board is made from bleached wood pulp and is treated with a buffering agent, like calcium carbonate, to make it acid-free. Buffered mat board is a little better than standard mat board. However, the buffering agent will gradually wear away or deteriorate. When this happens, you basically have standard mat board. While buffered mat board will offer acid-free protection for a while, it is NOT RECOMMENDED.
Acid-free mat board is made by chemically neutralizing the acids in bleached wood pulp. It is sometimes also buffered. However, acid-free mat board is not lignin (a complex polymer in wood) free. Eventually, acids and other chemicals in the lignin will begin to discolor and damage the artwork. While providing adequate protection for a period of time, acid-free mat board is NOT RECOMMENDED for archival museum quality matting.
100% Alpha Cellulose mat board is an acceptable archival museum quality mat board for use in matting your finest artwork. It is made from wood pulp, but has been emaciated and chemically purified to remove all lignin and other acidic chemicals. It is 100% acid-free and 100% lignin free. It is also buffered, to raise its pH* to 8.5-9.5, for additional protection.
Finally, the very best archival museum quality mat board that you can use for your artwork is 100% cotton rag mat board. It is not made from wood pulp, and is naturally 100% acid-free and 100% lignin free. Little purification is required because cotton is nearly 100% pure cellulose. 100% cotton rag mat board is also available in a buffered form, for additional protection in areas where light sources and airborne pollutant levels are high.
*pH is a chemical measurement of how acid or alkaline a material is. The pH scale goes from 0-14.0, with 7.0 being neutral. Numbers below 7.0 are acid, and above 7.0 are alkaline. The pH of a high quality archival museum quality mat board should be in the 8.5-9.5 range.
Colored Mat Boards –
Mat boards are available in literally hundreds of colors, including an amazing variety of whites and off-whites. Mat boards also are available in various patterns and textures. Today, mat board manufacturers have changed their color selections, in various grades of mat board, as consumers have become more aware and knowledgeable about the need for archival museum quality matting and framing for their most valuable artwork.
The three NOT RECOMMENDED mat boards above now come in a limited selection of colors. These three grades of mat board have legitimate short-term uses. In fact, many frame shops now explain and sell them for “temporary” or “short-term” matting of inexpensive artwork and other items that people might want displayed for a relatively short period of time. However, frame shops would offer no guarantee of longevity in using these grades of mat board.
Today, the 100% cotton rag mat boards are available in the largest selection of colors and variations. You can be as creative as you want in putting together a matting package for your artwork. You can double and triple mat for extra depth and interesting effects. For antique artwork, you can select off-white colored mats to match the color of the antique artwork’s paper. You can pickup a specific color in your artwork and use a matching colored mat. Or, you can do both by double matting. It is not necessary or recommended to use a colored back mat. You artwork lies directly on the back mat, and is never seen, so use a plain white back mat.
There are two other considerations when using colored mat boards. You should be CAUTIONED that not all colored mat boards, even some made from 100% cotton rag, are “color safe” or “color fast.” Colored mat boards that are not color safe can easily fade, even if protected by UV glass. More importantly, however, is the danger of non-color safe mat board colors running or bleeding when displayed in certain environmental situations. If colors run or bleed, they could ruin your artwork. This is further reason to never use colored mat board for the back mat. Various manufacturers will certify and label some of their colored mat boards as “color safe” or “color fast.” Use only those.
The 2nd consideration, when using colored mat board, is to realize that the color is only on the surface. When the beveled window cutout is made, the white inner core of the colored mat board will be exposed on all four inner edges, and will be next to your artwork. This may or may not matter to you. If you use a single colored top mat to pickup a color in your artwork, the white beveled edge inner core may closely blend or match the color of your artwork’s paper. You could use a white or off-white inner top mat, and double mat on top of that with a colored mat that picks up a color in your artwork.
There are at least two manufacturers, that I am aware of, who make a “solid core” 100% cotton rag mat board. This means that the surface color, and the color of the inner core, is identical. When the window mat cutout is made, the four beveled inner edges will match the surface color of the mat. This can be very useful, in either single or double matting, if you don’t like the look of the exposed stark white beveled inner core. Bainbridge makes a line of solid core colored mat boards, which I have seen, and Crescent has a similar line, which I have extensively used. These “solids” aren’t available yet in a wide range of colors. Until just recently, Crescent had only 25 colored solids, mostly off-whites plus beiges and grays and black. Both companies are regularly coming out with more colors for their solids. They are available in 2, 4, 6 and 8 ply, and either buffered or non-buffered.
Custom Mats –
Your local frame shop will custom cut the mat for your artwork and personally mount and assemble your artwork in a complete framing package ready to hang on your wall. While that is custom service, it is not a custom mat. You would find people with the knowledge and skill to create custom mats at upscale print dealers or art galleries, if your local frame shop does not do this work. The work requires a lot of experience and patience.
The simplest, and perhaps most elegant, custom mat that you can have done is the French mat. The term French line is also used to describe this mat finishing technique. Usually 1 or 2 fine accent lines are hand drawn around the entire window mat, using colors that are picked up from the artwork. If 2 lines are drawn, they run parallel to each other around the entire mat. Often the space between the two French lines will be hand painted with another complimentary color.
If you think it appropriate for your artwork or decorating scheme, you can order a hand painted mat. This requires an artist, but the possibilities are limited only to your imagination. Typically, one or more different decorations would be hand painted and evenly spaced around the entire window mat. A straight or wavy hand painted line might connect these painted decorations. Also, the cut beveled edges of the window mat can be painted with an accent color. If you cannot find just the right color, among the hundreds of available colored mat boards, the bevel and exposed surface of the lower mat (in a double mat system) can be custom painted to any color. Finally, a hand painted frame liner or fillet can be used between the glazing and top mat. They can be painted and decorated in any color, including metallic finishes.
Some people would say that the finest of all custom mats is the French Silk mat. Actually, the French Silk mat falls into a category of custom mats called “hand wrapped mats.” Hand wrapped mats fall into two categories, paper wrapped and fabric wrapped. In both types, a 4-8 ply 100% cotton rag mat is cut to size and the beveled window opening is cutout. At this point, the mat could be finished in any of the above-described techniques.
For a paper wrapped mat, the cutout window mat is hand wrapped with a 100% cotton rag artist’s watercolor paper. The paper can be any color, and any available finish or texture. From there, the custom mat can be decorated and finished with any or all of the techniques described above.
A fabric wrapped mat is a step above the paper wrapped mats. The process is the same as for a paper wrapped mat, except the mat is hand wrapped with a fabric. Fabric wrapped mats are made using linen, suede, satin or silk. I suppose of those four fabric types, silk could be considered the “queen” of fabric wrapped mats. The choice of fabric colors and textures is certainly in the hundreds, and probably exceeds the number of colored mats that are available. The silks and linens can also be hand painted with additional decorations and accents.
The variations for custom mats are only limited by your imagination, taste and pocketbook.
Completing the Mat Package –
A number of other details and techniques go into completing the mat package. The artwork cannot touch the glazing. The common use of a window top mat will generally provide enough space between the artwork and the glazing. If for some reason a top window mat is not used, either spacers or a frame liner or fillet will have to be used between the glazing and the back mat. Even if both a 4 ply top mat and back mat are used, it is generally recommended that a rigid backboard or backer board be used behind the back mat. Mat board is fairly rigid, but over time and under certain conditions, it could sag or warp. An acid-free backboard, such as foam core or tiger board, would prevent this.
The top mat and back mat are generally hinged along one common side so that the two pieces would fold open like a book. Acid-free archival linen tape is generally used. The top mat and back mat inner surfaces (the surfaces that will touch the artwork) are placed face up and two sides butted. A strip of linen tape applied straddling the butted seam will create the hinge. The artwork is secured or mounted to the back mat. Two T-hinges made from Japanese rice or mulberry paper, and attached using wheat or rice paste, is the best way to mount artwork. There is an acid-free paper tape roll available, with water-activated adhesive that is also used to make T-hinges. Clear acrylic or Mylar mounting corners can be used, if they do not prevent the top mat from lying flat and the artwork is not too tightly constricted. The T-hinge method is best because it allows for some natural expansion and contraction of the artwork. Dry mounting and heat-activated glues are not safe for your artwork. Also, there is no pressure sensitive adhesive tape that is safe for your artwork.
After the mat package is mounted in the frame, a polypropylene or polyester sheet should be affixed as a vapor barrier. This is especially important in cold weather climates where the frame is to be hung on an outside wall. Finally, the back of the frame is sealed with a special Kraft paper dust cover. In cold weather areas where the frame is hung on a colder outside wall, spacers are placed on the back of the frame to provide warmer air circulation behind the frame.
IF YOU VALUE YOUR AUDUBON PRINT, DO NOT FOLD OR TRIM IT TO FIT A SMALLER SIZED FRAME.
Encapsulation –
Frames Unlimited, a chain of framing shops here in the Midwest, offers a technique called encapsulation, for added protection, as part of their framing package. Encapsulation is a process that uses a gel adhesive to seal your artwork in a clear archival Mylar envelope. This clear envelope, containing the artwork, is mounted to the back mat in a mat package, and covered by the cutout window mat, for conventional matting of antique prints. I’ve seen a sample of their encapsulated artwork, but not matted and framed. This technique, though used in libraries for document storage, is not yet proven as a safe environment for artwork within a framing package
Alternative UV Protection –
When I purchased the condo I now live in, all windows with a south and west exposures were lined on the inside with a protective film. This film provides filtering out of 98% of UV light from the sun, and also filters out some percentage of the sun’s infra-red (IR) energy, which additionally helps cut down on air conditioning costs. These films are available in clear, tints and reflective colors. My reflective film has a 20 year warranty, and only reduces the amount of visible light in a room by 5%. If you cannot find a satisfactory UV glass (non-distorting and non color altering) to protect your artwork in a particular room, you might consider this option for UV light protection. These films are now available at Lowes, Home Depot and other home supply stores for do-it-yourself installation. However, you must not defeat the purpose of these films by using direct fluorescent or incandescent lighting on your artwork. Visible indoor light on valuable artwork should always be indirect.