# Material for shock-absorbing foam rubber and where to get a small piece? **URL:** \ **Category:** Factual Questions\ **Created:** [January 5, 2019, 5:00pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252 "2019-01-05T17:00:58Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![KidCharlemagne](https://avatars.discourse-cdn.com/v4/letter/k/ed8c4c/32.png) [@KidCharlemagne](https://boards.straightdope.com/u/KidCharlemagne)\ **Post date:** [January 5, 2019, 5:00pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/1 "2019-01-05T17:00:58Z")
I need to find a small piece of a medium density, very spongy foam rubber, ideally around 3/8 to 1/4 inch thick. I need to make a custom heel insert donut-like thing to straddle the hotspot on the back of my heel from heel bursitis. (none of the commercially available stuff can do what I want). It’s probably best if it’s dense enough to only compress around 50-60 percent by pinching with fingers. I looked on eBay but I’m not sure of the material I need because I see a lot of foam rubber that looks like those relatively large cell foams used for insulation. I’m wondering if there is a special synthetic material that I should be looking for and also where I might source a small or cheap piece of it. Thanks. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [January 5, 2019, 5:15pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/2 "2019-01-05T17:15:43Z")
I’d look for closed cell foam such as used in [this type of koozie](http://www.wellpromo.com/upload/upimg48/4-x3-3-8--Thick-Foam-Can-Coole-22448.jpg). The koozie’s circular bottom piece would probably work a treat after being cut to size. ---
**Author:** ![MindsEye\_Watering](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mindseye_watering/32/3619_2.png) [@MindsEye\_Watering](https://boards.straightdope.com/u/MindsEye_Watering)\ **Post date:** [January 5, 2019, 6:02pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/3 "2019-01-05T18:02:25Z")
[Sorbothane should work.](https://www.amazon.com/Isolate-Sorbothane-Vibration-Isolation-Square/dp/B0042U78H2/ref=sr_1_14?s=hi&ie=UTF8&qid=1546711193&sr=1-14&keywords=sorbothane) ---
**Author:** ![KidCharlemagne](https://avatars.discourse-cdn.com/v4/letter/k/ed8c4c/32.png) [@KidCharlemagne](https://boards.straightdope.com/u/KidCharlemagne)\ **Post date:** [January 5, 2019, 6:13pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/4 "2019-01-05T18:13:40Z")
> [@Gary\_T](#): > > I’d look for closed cell foam such as used in [this type of koozie](http://www.wellpromo.com/upload/upimg48/4-x3-3-8--Thick-Foam-Can-Coole-22448.jpg). The koozie’s circular bottom piece would probably work a treat after being cut to size. Ah yes, that’s exactly the kind of foam I’m looking for. I knew it was everywhere I just couldn’t think of where. Thanks. ---
**Author:** ![KidCharlemagne](https://avatars.discourse-cdn.com/v4/letter/k/ed8c4c/32.png) [@KidCharlemagne](https://boards.straightdope.com/u/KidCharlemagne)\ **Post date:** [January 5, 2019, 6:20pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/5 "2019-01-05T18:20:20Z")
> [@Gary\_T](#): > > I’d look for closed cell foam such as used in [this type of koozie](http://www.wellpromo.com/upload/upimg48/4-x3-3-8--Thick-Foam-Can-Coole-22448.jpg). The koozie’s circular bottom piece would probably work a treat after being cut to size. Whoops missed my edit window. Do you happen to know if a koozie would be considered med or high density foam? ---
**Author:** ![aethelred](https://avatars.discourse-cdn.com/v4/letter/a/dec6dc/32.png) [@aethelred](https://boards.straightdope.com/u/aethelred)\ **Post date:** [January 5, 2019, 9:05pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/6 "2019-01-05T21:05:25Z")
I suspect you will probably want to experiment with multiple thickness/density combinations until you find the one which works best (might even be different depending on how long you are going to be wearing a given shoe/boot, what the heel angle is, etc.). You might want to look at “super-cushioning foam” here > **[McMaster-Carr](https://www.mcmaster.com/foam)** > > McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day. (sorry - I can’t seem to make a link to the “super-cushioning foam” subpage - operator error, no doubt) I’ve found McMaster Carr to be pretty good about coughing up samples for nominal costs, sometimes free, although the fact that I buy a few hundred bucks per year of stuff from them probably helps with that. You don’t list your location, but if you’re in a large city there is a probably a foam distributor near you that you can scrounge scraps from. ---
**Author:** ![Littleman](https://avatars.discourse-cdn.com/v4/letter/l/ccd318/32.png) [@Littleman](https://boards.straightdope.com/u/Littleman)\ **Post date:** [January 5, 2019, 9:15pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/7 "2019-01-05T21:15:46Z")
How about a jumbo pool noodle? Or perhaps a kickboard. Otherwise I believe what you’re looking for Is called EVA foam. A quick Google search will reveal a great many sources. ---
**Author:** ![Littleman](https://avatars.discourse-cdn.com/v4/letter/l/ccd318/32.png) [@Littleman](https://boards.straightdope.com/u/Littleman)\ **Post date:** [January 5, 2019, 9:28pm UTC](https://boards.straightdope.com/t/material-for-shock-absorbing-foam-rubber-and-where-to-get-a-small-piece/827252/8 "2019-01-05T21:28:04Z")
Amazon has many thicknesses, hobby lobby has 5mm and 2mm which could be glued together with contact cement. Idk if those floor puzzle pieces things are made thin enough. Anyhow EVA should get you started.