Email digest for the Global Conservation Forum (ConsDistList) egroup. ------------------------------------------------------------------------------------------------------------
1. RE: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas 2. RE: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas 3. RE: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas ------------------------------------------------------------------------------------------------------------ 1.From: Elizabeth McDermott Posted: Sunday June 14, 2026 9:40 AM Subject: RE: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas Message: Hi Heather, You will need to consider the weight of the object in relation to the shear strength of the magnets. There are different grades of magnets all with varying axial pull forces and relative shear strengths. The size, thickness, composition, and grade of the magnets should be carefully considered, as well as the surface area and texture with which the magnets are in contact. Gwen Spicer wrote a fantastic book called Magnetic Mounting Systems for Museums, which I highly recommended. What Gwen calls "continuous pressure" mounting systems might be a great option for you. My concern for this particular object when using a magnetic mounting system would be the texture of the canvas on the verso detracting from the surface area in contact with the magnetic system that you eventually create. I think that it's doable but will require some shear strength testing after weighing the object and running some calculations regarding shear strength. Testing will need to include any protective covering you add (like muslin or Japanese tissue) to prevent abrasion as well. Hope this helps! Liz ------------------------------ Elizabeth McDermott Senior Conservation Technician/Exhibits University of Pennsylvania Libraries Yeadon United States ------------------------------ ------------------------------------------- Original Message: Sent: 06-11-2026 14:25 From: Heather Adams Subject: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas Hello, We have a 12x8 foot paper poster mounted on canvas. The goal is to digitize and then roll it for storage. We're considering hanging it for just long enough to get good images of it. It's been lying on top of shelves for as long as I've been alive, and we have no idea what the condition will be when it comes down. Does anyone have a rule of thumb of the weight magnets could hold, or do you have other ideas for how to hang it? Thanks, Heather ------------------------------ Heather Parks Head of Preservation & Conservation Binghamton University [email protected] <[email protected]> ------------------------------ 2.From: Zuzanna Szozda Posted: Sunday June 14, 2026 5:26 PM Subject: RE: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas Message: Dear Heather, I think magnets can certainly be a viable option. However, a few practical considerations may be worth keeping in mind. One aspect worth considering is that calculators such as the K&J Magnetics tool estimate the direct pull force of a magnet, but they do not directly predict whether a large sheet or canvas-mounted object will remain safely in place. In practice, a relevant parameter here is the extraction force, which is closely related to the coefficient of friction between all contact surfaces. As a result, the effective holding capacity can vary considerably depending on the materials involved, surface texture, protective interleaving layers, and the actual contact pressure. For this reason, pull force alone may not be a reliable predictor of how well the object will resist slipping once suspended. In other words, the question is often not how much weight a magnet can lift, but also how well the entire mounting system can resist slipping. I also agree with George's suggestion that distributing the load over a larger area is often safer than relying on a limited number of high-force magnetic contact points. The condition of the object will probably be the key factor in determining how much contact pressure can be applied safely. If the poster has been stored for many years and its condition is still unknown, I would be cautious about concentrating forces in only a few locations. The application and removal of strong magnets can also be challenging and, in some situations, may present a greater risk than the actual hanging period. For fragile objects, it may therefore be worth considering systems that allow a more gradual and controlled engagement of magnetic force rather than relying on magnets that snap into place at full strength. Here perhaps, a mounting system that allows the contact pressure to be adjusted and distributed over a larger area may offer additional safety compared with relying solely on the maximum strength of fixed magnets. One example would be magnetic holders with adjustable pressure, which allow the holding force to be introduced gradually and controlled during both mounting and removal. I discussed this type of approach during the AIC Annual Meeting in Los Angeles in 2022. If you or anyone else is interested further in the topic, I would be happy to share relevant references and ongoing research. My current PhD research focuses on the use of magnets in the conservation, mounting, and display, including the mechanical interactions between magnetic systems and art materials. It sounds like a fascinating project, and hopefully the poster will be in better condition than expected after all these years. Best of luck with the digitization, and I would be very interested to hear what solution you eventually choose. Best wishes, Zuzanna ------------------------------ Zuzanna Szozda Paintings Conservator Copenhagen, Denmark [email protected] ------------------------------ ------------------------------------------- Original Message: Sent: 06-11-2026 14:25 From: Heather Adams Subject: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas Hello, We have a 12x8 foot paper poster mounted on canvas. The goal is to digitize and then roll it for storage. We're considering hanging it for just long enough to get good images of it. It's been lying on top of shelves for as long as I've been alive, and we have no idea what the condition will be when it comes down. Does anyone have a rule of thumb of the weight magnets could hold, or do you have other ideas for how to hang it? Thanks, Heather ------------------------------ Heather Parks Head of Preservation & Conservation Binghamton University [email protected] <[email protected]> ------------------------------ 3.From: George Schwartz Posted: Sunday June 14, 2026 10:00 PM Subject: RE: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas Message: Here is another practical method that doesn't require calculating and configuring a magnetic mount. Use gripper clips designed for tarpaulins. You will want to pad the jaws with a non-slip, high-grip benign layer at least on the face side to improve the clips staying put. I recommend asking your phlebotomist for a few disposable rubber tourniquets they use when drawing blood. You can pass a tight wire rope through the holes, or put a series of nails into the wall where you want to hang the map. The clips are easy to close and open, without the risk of prying powerful magnets off a paper surface. If you have your heart set on using magnets, I understand well, the cool factor. I'm a confirmed magnet geek myself. I can draw up a tried and true design and send it to you. Personally, it would be overkill in this application and far more costly. good luck George ------------------------------ George Schwartz Principal, Senior Conservator ConservArt, Inc. Boca Raton FL [email protected] Chair CIPP 2011-2013 Conservators in Private Practice ------------------------------ ------------------------------------------- Original Message: Sent: 06-14-2026 16:32 From: Zuzanna Szozda Subject: Using magnets to temporarily display massive 12x8 foot paper poster mounted on canvas Dear Heather, I think magnets can certainly be a viable option. However, a few practical considerations may be worth keeping in mind. One aspect worth considering is that calculators such as the K&J Magnetics tool estimate the direct pull force of a magnet, but they do not directly predict whether a large sheet or canvas-mounted object will remain safely in place. In practice, a relevant parameter here is the extraction force, which is closely related to the coefficient of friction between all contact surfaces. As a result, the effective holding capacity can vary considerably depending on the materials involved, surface texture, protective interleaving layers, and the actual contact pressure. For this reason, pull force alone may not be a reliable predictor of how well the object will resist slipping once suspended. In other words, the question is often not how much weight a magnet can lift, but also how well the entire mounting system can resist slipping. I also agree with George's suggestion that distributing the load over a larger area is often safer than relying on a limited number of high-force magnetic contact points. The condition of the object will probably be the key factor in determining how much contact pressure can be applied safely. If the poster has been stored for many years and its condition is still unknown, I would be cautious about concentrating forces in only a few locations. The application and removal of strong magnets can also be challenging and, in some situations, may present a greater risk than the actual hanging period. For fragile objects, it may therefore be worth considering systems that allow a more gradual and controlled engagement of magnetic force rather than relying on magnets that snap into place at full strength. Here perhaps, a mounting system that allows the contact pressure to be adjusted and distributed over a larger area may offer additional safety compared with relying solely on the maximum strength of fixed magnets. One example would be magnetic holders with adjustable pressure, which allow the holding force to be introduced gradually and controlled during both mounting and removal. I discussed this type of approach during the AIC Annual Meeting in Los Angeles in 2022. If you or anyone else is interested further in the topic, I would be happy to share relevant references and ongoing research. My current PhD research focuses on the use of magnets in the conservation, mounting, and display, including the mechanical interactions between magnetic systems and art materials. It sounds like a fascinating project, and hopefully the poster will be in better condition than expected after all these years. Best of luck with the digitization, and I would be very interested to hear what solution you eventually choose. Best wishes, Zuzanna ------------------------------ Zuzanna Szozda Paintings Conservator Copenhagen, Denmark [email protected] <[email protected]> ------------------------------ You are subscribed to "Global Conservation Forum (ConsDistList)" as [email protected]. To change your subscriptions, go to http://community.culturalheritage.org/preferences?section=Subscriptions. To unsubscribe from this community discussion, go to https://community.culturalheritage.org/HigherLogic/eGroups/Unsubscribe.aspx?UserKey=d16eaa87-0f69-494b-9f2f-303dbc1222e1&sKey=fab9aa4f27a04c5d876e&GroupKey=757a8f16-505f-4323-8e74-e376757aa9f7.
