I am writing up an article on what types of foam to use (not just for muppet-types so if you have other suggestions, let me know!). However, I'm really confused on "reticulated" vs "polyfoam". It seems they are two different things, based on the conversation on this site; but when I checked my enquiries to a foam supplier, they used "reticulated" to refer to EVA foam, when some people use EVA foam to refer to polyfoam.

Can someone please give me a succinct explanation as to what they are called by the manufacturer and what the differences between the two are?

Thanks!

PS. Continually amazed at the amount of info that is here for all to find.

I don't think you are going to get a solid answer on this one.   Seems as if ever seller has different names.  Here is how I see it.

Polyfoam is what I use when I am refering to the foam sheets you get at hobby and craft stores. As a rule it is what you find in chair cushions.

Reticulated foam looks a bit like air conditioning filter in that it is very open almost like a sea sponge.

EVA foam is very dense foam and most commonly used to make cushions on boats and docks because it is "water proof". It is often refereed to as close celled foam.

I think really that they all kind of fall under the heading of Polyfoam but that each is a different process and I am sure mix of chemicals and agents.

I ordered some foam that was close to reticulated from Albany foam http://albanyfoam.com/ It was called E-Z dry and is used for cushions in outdoor furniture. As Shawn said the reticulated I think is primarily used to make filters in air conditioning and heating systems. There are some craft products made from eva foam as well.

http://www.foamonline.com/types.php?cartID=c1b5e3eb832637baf8a28253af55a770

Good link Billy!  The "Closed Cell Foam" that is shown on that page is what my supplier calls EVA foam.

This confused me for years, but after learning from some chemists and talking to companies that actually manufacture foam, I think I can give you a pretty definitive answer. Really, there are only two types of foam - open cell foam and closed cell foam. Every type and brand of foam fits under one of those two categories.

Open cell foam has an "open" structure and is usually very soft and pliable. One characteristic of it is that it contains pores that can be filled with a liquid (like water) or gas (like air). For example, synthetic dish sponges are made from open cell foam, which is why they can absorb water. Open cell foams are reticulated, which just means they are structured like a web or a net. What is commonly called "reticulated foam" in puppet building circles is actually industrial filter foam that is usually manufactured to make filters for air conditioners as mentioned above. What's often called "Polyfoam" (short for polyurethane foam) is the type of foam rubber that couch cushions and mattresses get made from. Technically speaking they are both open cell foam and therefore reticulated foam.

Closed cell foam does not have pores and is usually stronger and harder than open cell foam. An example of a closed cell foam is L200/400/600 foam, which is known to many people as "craft foam" or "Foamie" when it's sold in thin sheets. As I think Shawn mentioned, closed cell foams are typically used for marine applications because it floats and does not absorb water because of it's "closed cell" structure. Pool noodles are manufactured from closed cell foam and it's also used to make life jackets.

EVA stands for Ethylene-vinyl acetate, which is used to make lots of things like wetsuits, hot glue, and even body bags. It's a type of polymer (technically, it's a copolymer) that can be used to make foam, so all "EVA foam" means is that it's a foam made from EVA. All of the EVA foams I've ever seen are closed cell foams, although it's probably possible to manufacture an open cell foam using EVA, which might explain the confusion.

Does that make sense?

Is it possible that we can award Andrew an honorary doctorate in Puppetry? I know this could lead to some confusion what with Jay already having the tag of Dr. Puppet but I just feel like Andrew deserves a PHD after his name. I know we have a great many experts with so much knowledge that contribute regularly here and I appreciate you all. I'm just always amazed by Andrew's breadth and depth of knowledge and the scholarly approach he uses.

I'm seriously considering just following you around Andrew to learn just a tiny bit of what you know and thus greatly expanding my knowledge. Of course I'd have to move to Canada and I don't think my wife will let me take her much farther north than we already are. Ah well, I suppose I'll have to content myself with the bits of knowledge I pick up from you (and all my other "teachers") via the interwebs.

Thank you SO MUCH Andrew. It all makes sense now. I think actually the article will just be made up of your answer in the form of a quote. I do wish you'd come here more often and leave comments, because they're always extremely useful.

On a related question: what do people use when making marionettes out of foam? And are the above foams also used for other types of puppets, like rod puppets, etc?

that was an AWESOME description Andrew!

Speaking of L200... does anyone know of a craft store that sells it in thick pieces or blocks? I've looked at Joanns, Michaels & AC Moore but then again, maybe I'm not looking in the right spot.   Would I have better luck at a hobby store?

I agree with the above folks... Andrews answer really hits it on the nose.  Wish I had that talent for explaining things.

@Goochman I doubt you are going to be able to find the close cell or L200 foam in a craft or hobby store.  I imagine you are going to have to get it on-line in less you are lucky enough like me to have a company in town that sells it. The company here in Kansas City is called Comfort Felt and Foam and it sell to manufactures of furniture, pillows, boating goods ect. Luckily they have been very kind to the theater community in town and let us walk in off the streets to get foam. Granted you have to buy at least a full sheet of the foam but that is not really a bad thing. Also they have a "trash" bin that you can look through and get scraps for cheap or even sometimes free when you buy other stock.

@Na  I use the close cell foam to make the upper torso of my marionettes some time but that is about it.  I do know that some of the members here have been using the regular open cell foam to sculpt body parts and heads even for rod puppets and marionettes. Most of them seem to use a structure under the foam like wood or something though.

Thanks Shawn. I recall Fratello Marionettes uses floral styrofoam, I did a workshop with him at the puppetry festival in Atlanta. Interesting how there are so many different options for one product.

I've now added my article, found here:
http://www.schoolofpuppetry.com.au/tutorials.php/how-to-make-a-foam-puppet-aamp-what-kinds-of-foam-to-use

Thanks again Andrew for the help!

I purchased foam from a couple suppliers for years. One closed, the other quit selling the foam I used. 
I've been to two different foam places to purchase foam, and they asked what density I wanted.  I really had no clue.  One place, the guy said he would suggest a sheet of their cheapest foam, and if that did not work we could do something else (it was not what I needed). The other place sold me rolls of narrow pieces that they had cut from larger rolls.  This worked well, as I could experiment with several densities and decide what was best.  Now I will take a piece of the one I liked the best and they will sell me larger pieces.  I have no clue which density this is, but they said they can tell by looking at it.    Said all that to say... perhaps we should be listing densities to help folks getting started. 

Sorry Na but I have to disagree on your section entitled Common myth: polystyrene or "styrofoam".  I think the thing that triggered me on this the most was the line "Anyone who writes this hasn’t spent a lot of time using or making puppets.". Ahh... I would use it and have used it.  Remember that just like the poly foam that is used to make the common hand in mouth puppet, there are a large variety of grades and types of polystyrene foams. We are all more comfortable with different mediums and I feel you should take that into account. Do not dismiss someones work simply because of the medium they have chosen to work in.

P.S.
It is a great article overall.    I didn't want you to think I didn't appreciate it.

Actually, I kind of agree with you. Initially I had written it up in terms of "styrofoam" because that's the most common term used in hobby tutorials on puppets for kids. Then when I realised that floral styrofoam was used by Fratello, I rewrote it.

The problem I have is that 99% of the free tutorials out there do recommend using things like polystyrene cups for making muppet heads. While I think polystyrene is perfectly fine to use for certain puppets, the aim of the article is mainly towards those making muppet-type puppets and in this case recommending people away from polystyrene is probably a good idea.

Maybe another rewrite of that section is necessary, with some clarification in regards to what I just said here.  EDITED TO ADD: I've made a footnote explaining my reasons at the bottom of the article, along with removing a few small sentences from the actual paragraph in question.

I'm certainly not dismissing other people's choice of materials, but you've got to remember my readership is mainly non-puppeteers who want professional results without having to wade through nuance to get it. I do actually say at the beginning of every article on materials that you can use whatever you want, but some things might be better for your needs.

Plus, I have used polystyrene before and had it break down on me when trying to use it.

Feel free to criticise, I enjoy discussing this stuff, and am more than happy to make changes where I'm wrong.

I purchased foam from a couple suppliers for years. One closed, the other quit selling the foam I used. 
I've been to two different foam places to purchase foam, and they asked what density I wanted.  I really had no clue.  One place, the guy said he would suggest a sheet of their cheapest foam, and if that did not work we could do something else (it was not what I needed). The other place sold me rolls of narrow pieces that they had cut from larger rolls.  This worked well, as I could experiment with several densities and decide what was best.  Now I will take a piece of the one I liked the best and they will sell me larger pieces.  I have no clue which density this is, but they said they can tell by looking at it.    Said all that to say... perhaps we should be listing densities to help folks getting started. 

Forgot to say this is a good idea: what densities are commonly used?