Steve Briscoe 8/13/08

Has anyone used 9lb foam as decking in cases? Are there issues with fabric covering? Is it sturdy enough to hold mounts? I'm doing some tests for upcoming work and looking for a source of 9lb foam. I know Small Corp makes an 'Ethadeck' consisting of alpolic, foam and fabric, but I can't afford their fancy ways. My supplier has 2" but won't slit it into 1" planks. Is it available thinner?  Has anyone tried HDPE cutting board material or is that too wacky? Steve Briscoe Preparator, History Department Oakland Museum of California 1000 Oak Street Oakland, CA 94607 510-238-2244 510-238-3044 Fax www.museumca.org

Philip Brutz

8/13/08

We have been using ½” 9 lb Ethafoam on top of ¾” medex for our decks and back boards when we need to use pins.  It will hold small mounts and for heavy mounts we drill back into the medex.  We attach the fabric with staples on the under side of the deck.  Our suppler is BB Bradley 440-354-0039.  They still have Dow Chemical brand Foam.

Philip Brutz

Mountmaker

Cleveland Museum of Art

11150 East Blvd.

Cleveland, OH 44106-1797

216-707-2617

Jim

8/13/08

RE: [mountmaking-forum] Re: Source of 9lb foam?

The Detroit Institute of Arts has used 1/2” 9 lb in the same way, for the same benefits, as Philip has described.  Our supplier is American Excelsior. Google them and you’ll find a contact number for your area.   

Jim

Steve Briscoe 8/13/08

Re: [mountmaking-forum] Re: Source of 9lb foam? Then are you sealing the Medex with Marvelseal or paint? Steve

Philip Brutz 8/14/08

RE: [mountmaking-forum] Re: Source of 9lb foam? We have been sealing with a clear acrylic water based varnish but we are now covering our decks with Marvelseal.  This is a very big issue for us right now.  What are other museums using?

Mendez 8/14/08

Contact Sealed Air (sealedair.com) and find a sales representative in your area. The rep should be able to hook you up with a fabrication house that will either slice a plank of 9 lb foam. Or if you like, you may be able to purchase a sheet of their 1.5" foam. Keep in mind that the density of these foams are inconsistent along the edges of the fabricated planks and you may find the sniped end unusable (usually the last inch or two).

This foam hold mounts very well, but you may have to add a second support foot along a single rod to prevent it from rotating. You may also want to make sure your post is long enough to penetrate the thickness of the foam and attach into a more denser substrate lying below. There are issues with fabric-covering this stuff but there are creative solutions as well. Beva film works the best, but you have to use the thicker of the two available, and you have to use the appropriate weight fabric because something too thin and too flat will show the texture of the foam and overheating may allow the Beva gel to penetrate to the surface of the fabric. The Beva film has to be applied to the foam first with a hot --and dry-- iron. The fabric is ironed on next.

HDPE sounds expensive and may not offer the versatility of object placement the foam provides, but if you can cover your deck with an approved aggregate, or a fabric-wrapped layer of thin acrylic that hides previously drilled holes, I'd say use it. HDPE (drilled at a slightly smaller diameter than your mounting post) offers a great 'grab' for brass and steel, but not so well for aluminum over time.

steve 8/14/08

RE: [mountmaking-forum] Re: Source of 9lb foam? I have fabric covered 9 lb foam by cutting a slit about 1-1/2" or so inboard on the back of the foam then pushing the fabric into the slit with a blunt burnishing tool. The foam holds the fabric quite well if the slit is 1/2" deep or better.  A piece of cotton cord can be pushed in afterward securing it even more. This works sort of like installing a new piece of screen in a window screen.  After the fabric is stretched in to place and secured, the excess can be cut off.  This way, no adhesives are used and fabric can be easily changed.

Steve Briscoe

8/14/08

Re: [mountmaking-forum] Re: Source of 9lb foam?

I like that. We've been using that technique to make basket storage   mounts using tyvek pushed into slits in the foam. So you're using it   without a wood backing? Is curling an issue?

I called Small Corp (website sucks, call them) about the ethadeck   thing they make with Dibond and 9 lb foam. She told me the foam alone   would curl, which in my heart I probably knew. Expensive though. A   hypothetical 36" square was $235+shipping.

We have always used MDF or ply covered with Marvelseal then fabric   using a mylar tape by 3M. Hard to get the really crisp corners that   other places get, but we manage. From the roving techs I hear the   deYoung and Asian seal with a paint then glue (Yes glue?) down the   fabric. This doesn't sound any easier, just different with more   chemicals. I'll stick with our method until we can invent something   better.

Steve Briscoe 8/14/08

Re: [mountmaking-forum] Re: Source of 9lb foam? And what are you using to glue foam to wood? Hot glue?

Philip Brutz 8/14/08

RE: [mountmaking-forum] Re: Source of 9lb foam? We staple the foam to the wood.

steve 8/14/08

RE: [mountmaking-forum] Re: Source of 9lb foam? Curling depends on the type of fabric being used, how much tension required to get a nice surface, and the thickness of the foam.  The thin stuff, 1" or less will require backing which I have done using "T" nuts in the foam and screwing a backing board to it.  We made some shaped panels for some textiles where the panel matched the shape of the textile using 2" foam and only a small,( much smaller than the outside shape), without any curling problems.  I have also used the same method for attaching fabric to wood panels. I cut a groove on the table saw all the way around about an inch or so inboard and attach the fabric using screen beading,(that rubber cord that you put screens in with) with great success.  You could put a thin panel of foam on a board and cover them together with the same method.

Suzi McG 8/15/08

Re: [mountmaking-forum] Re: Source of 9lb foam? I worked on an exhibit years ago where they had a very large panel of medex, maybe 5' x 2.5' set at an angle.  The fabricator cut out some of the medex to inset pieces of foam for me to pin the objects into.  They liked the idea because they didn't have to use a whole lot of foam  - just where they really needed it.  Using smaller pieces they were able to cut it to size to match the thickness of the medex pretty well.  (I'm not exactly sure how - that wasn't my job.)  They held the foam in place with straps of material stapled into the back of the medex and then fabric wrapped the entire panel.  It looked very clean and did a nice job.

Suzi

Steve Briscoe 8/15/08

Re: [mountmaking-forum] Re: Source of 9lb foam? That's a cool idea. And the edges would be crisper with wood. Of course, it would help to have the case laid out before the thing gets fabricated! Our spontaneous ways might thwart that. SB

Philip Brutz

8/22/08

Hot Glue

I need to glue ethafoam together.  What is the best hot glue to use?

Philip Brutz

Mountmaker

Cleveland Museum of Art

11150 East Blvd.

Cleveland, OH 44106-1797

216-707-2617

Steve Briscoe 8/22/08

Re: [mountmaking-forum] Hot Glue We use and like the 3M 3792 LM which is clearish and adheres well. It's a low temp glue and so not as ouch-y. I believe our conservator is recommending a change to the high temp 3797. I think I remember a post about the Getty's favorite being tested, but can't find it. I think it might be the 3797. The 3M rep says they are all very similar EVA based products with slightly different properties based on what is to be glued. I've also heat joined Ethafoam with a heat gun. For small things this is easy. You have to hold it together in a Vee and throw the heat between. Depending on your technique it can be a weak or strong joint. It will allow you to build up several layers or edge joint two pieces quickly. It cools fast and no gluey mess.  Steve