Three messages on encapsulation procedures.---------Johnnie ------------------------------------------------ Fri, 04 Mar 94 11:19:28 CST Donna Koepp <[log in to unmask]> Encapsulation My experience here at University of Kansas has been with encapsulating the maps from the U.S. Congressional Serial Set. We deacidified the maps before encapsulation using Wei T'O Soft Spray. We sealed the Mylar with an ultrasonic welder, but even with this process we have raw edges of mylar, because the Minter Ultrasonic Welder does not seal the very edge, but a small distance in from the edge. We did however, invest in a corner rounder, which I think is probably the key to preventing damage to other non-encapsulated maps. My recommendation for thickness of Mylar would be 5 mil, depending upon the size of your map. With two pieces of paper between the Mylar sheets, I think you would need this thickness. We used 3 mil for the maps we have encapsulated here, but that was really pretty thin for the largest of the maps. We did it just for expediency in using the Minter Ultrasonic welder, which does not easily accomodate the thicker Mylar. Just from experience, I think you may find that the map will move around within the envelope with two pieces of paper in there. The thing that keeps the map stable is the static that builds up between the mylar sheets, and you will lose that by having two sheets, which will have some airspace between them. I think you will need to trim the mylar very close to the map to hold the map in place. Then, of course, you run the risk with tape, that the map may come into contact with the adhesive. My thoughts on the security strip, is that it should be on the side of the acid free paper AWAY from the map. Those strips are highly acidic, or so I have heard, and I think it would not be a good idea to have it in contact with the map. If you are taping the edges of the mylar, how about putting it along the edge as part of the tape holding the mylar closed? Just a thought. Otherwise, could you put it under a piece of tape on the acid free paper, and have that piece of tape be your label, to somewhat disguise it? Good luck. Sounds like a good project. Donna Koepp University of Kansas Government Documents and Map Library 913 864 4660 DOCSMAP@UKANVM ------------------------------------------------ Fri, 4 Mar 94 10:32:13 HST Ross Togashi <[log in to unmask]> Re: Encapsulation Greetings, Regarding map encapsulation, this is how we do it over here. 1) We use 4mil on the majority of our encapsulation, but go to a heavier 5mil if we feel that the map needs more support because it is large or poor shape, and if it is an item that is frequently handled. We own a ultrasonic encapsulating machine which is capable of sealing various thickness of polyester and so, no longer use double-sided tape. 2) We do not tattle tape any of our maps. At the moment, our map collection is a "closed-stacks" library with staff on hand whenever we are open to the public. 3) I don't quite understand your fear about sharp edges of the polyester. The only thing that has potential for damage is the corners, but we round them off with a corner rounder (scissors will do fine) so that they do not poke any other map or person. I've never thought about using single-sided tape on the outside, but imagine that eventually the tape will either rub or peel off. Also, there will be a problem of the tape being unable to flex with the polyester, which might make the tape buckle and eventually come off. If you haven't yet, I would recommend that you take a look at _Polyester Film Encapsulation_, by the Library of Congress. SuDoc no. LC 1.2 P76. It shows how to encapsulate and has good illustrations, showing step-by-step how to do it. Aloha, Ross Togashi University of Hawaii at Manoa Hamilton Library Map Collection ------------------------------------------------------ Fri, 04 Mar 94 09:21 PST "Carlos B. Hagen-L" <[log in to unmask]> Re: Encapsulation Hello. My name is Eric Scott. I'm an L.A. at the UCLA Map Library. I handle most of the preservation here--which is minimal, unfortunately. Regarding encapsulations, we use 3 mil mylar which we obtain from Conservation Resources in Alexandria, VA. We do not add a sheet of acid-free paper as this is more expensive and makes the material being encapsulated so thick that the map can move around. We use double sided tape and very neatly trim the mylar to within about 1/8" of the tape and round the corners. We avoid exposing the tape as the glue can stick to other maps within the folders. We've never had a problem with the edges cutting or tearing other maps, only sharp corners seem to be a problem. I use double-sided tattle tape and put it right along the edge of the mylar in place of a section of the double-sided tape. I started doing this myself--I haven't heard of anyone else doing it. I figure if anyone is going to try to get out the tattle tape, they are going to destroy the encap sulation. At that point, they would probably just try to cut the map out of the mylar. We don't usually let our valuable maps out of our sight that long. I would argue that, with maps, an obviously tattle taped item is discouraging enough in itself for all but the most serious theives, etc. I hope this info. is useful. If you would like to querry me further, you can reach me via e-mail: ECZ5EDS.MVS.OAC.UCLA.EDU Or by phone (310) 825-3493 8am-5pm PST. Good luck!------Original message---------------------------- Eric Scott. > > We are considering encapsulating some of our more fragile and irreplacable > maps. We are going to buy rolls of polyester, sandwich the map along with a > piece of acid-free paper with tattle tape attached. I have a few questions > about this process: > 1. Is ther a recommended thickness of polyester that we should use? > 2. Should we place the tattle tape between the map and the sheet of paper so > that it is invissible to any user or, place it on the visable side of the > acid-free sheet of paper away from the map but in plain sight? I guess we > could cover it with tape, however, how hidden would it be? > 3. We had thought to use the double sided tape companies sell along with the > film, however, I have a concern with that. Does the use of double-sided tape > leave sharp, polyester edges free to slice through other maps in the drawer? > Does anyone use single-sided tape on the outside of the sandwich, putting > tape on the front sheet of poly, folding the tape over the edge (therefore > covering those sharp edges) and sticking the tape to the back sheet? Does > anyone sew the sheets of polyester together? (You still have sharp edges, but > the preservationists fear of adhesive is gone.) > Thanks for your advise and assistance. > > Michael McDonnell > Waldo Library > Western Michigan University > Kalamazoo, MI 49008 > 616 387-5208 > [log in to unmask]