Foam To Make A Backpack Back Protector

[DayTrip]

I have a ULA CDT backpack that I love with the nagging exception of the flimsy foam pad that helps to protect your back from the pack's contents. It is a relatively dense foam about 1/4 inch thick so unless the pack is absolutely stuffed it tends to sag, fall out of the little loops inside holding it and wrinkle up at the bottom. So I figured I'd order a thicker piece of foam to remake the pad so it had more substance and could be a bit larger so it can't slip out of the loops inside....

And then I Googled "foam" and got about 11 trillion types of foam by the sheet, roll, etc. Is there a specific type of foam that gets used in packs? I went to the ULA site but it only describes a "foam pad". I'd like to get something about 1 inch thick so it helps provide a bit more structure to the pack, especially when it isn't fully loaded. I want it to be dense enough to possibly punch some holes in it too for ventilation. The existing 1/4 in pad is brutal for trapped heat and sweating. (Yes I know it is ultralight and that is part of the trade off).

So for the DIY'ers on here what type of foam should I be looking to use? Is there a such thing as antimicrobial/bacteria resistant types? Thanks in advance for any suggestions on tweaking a pack like this.

 

[JToll]

You could ask ULA for a recommendation for a supplier of foam.

 

[JustJoe]

You probably want something like this.
https://www.amazon.com/dp/B08TWWLWY...olid=1KLDAG9FZBFQ4&psc=1&ref_=lv_ov_lig_dp_it

 

[DayTrip]

You could ask ULA for a recommendation for a supplier of foam.

I don't particularly like the foam they used. I just wanted to know what type of foam it was so I could avoid that type. I supposed they'd recommend something though. I've emailed them a few times with questions and they have been pretty quick to respond and helpful. Like that company.

 

[DayTrip]

You probably want something like this.
https://www.amazon.com/dp/B08TWWLWY...olid=1KLDAG9FZBFQ4&psc=1&ref_=lv_ov_lig_dp_it

I was actually looking at gun case foam earlier. Supposed to be very firm and apparently has some sort of moisture resistance, which could be helpful given the application. I wish foam had some sort of classification for use and characteristics, i.e. how well it compresses, rips, degrades, etc. There is foam for hundreds of applications but they are all described simply as foam.

 

[jfb]

https://www.mec.ca/en/product/0808-022/evazote-winter-sleeping-pad?colour=NO_COLOUR

 

[dug]

You could disregard a one-to-one replacement, and instead take a 1/3 piece of Ridge-Rest and slip it inside between your gear and your back. Then when you get to camp, take it out and use it to kneel on, sit on, a table, etc.

 

[DayTrip]

You could disregard a one-to-one replacement, and instead take a 1/3 piece of Ridge-Rest and slip it inside between your gear and your back. Then when you get to camp, take it out and use it to kneel on, sit on, a table, etc.

That is actually what I am currently doing with an old Z-Fold pad I had. It does provide better support than the initial foam but because it is in foldable panels it is still kind of annoying wanting to collapse, fall out of the loops, etc. I think a more rigid panel would be better.

 

[dug]

Yes the Z-rest doesn't work quite as well as a Ridge-rest (do they still make them?) But the usability in all 4-seasons of such a lightweight item for inside the pack, around camp, on summits on dayhikes (painting moldings, weeding, emptying the pool skimmer, sitting on a metal bench at the soccer field, etc. LOL) makes it vital.

 

[peakbagger]

The US military uses a dense foam for sleeping pads. They are cheap, usually the shipping is as much as the pad. You can pick them up at military surplus stores or on Ebay. I ordered a couple of them during covid and they go lost in the mail so the vendor shipped another 2. About two months later the original set appeared so I have plenty of foam in stock. Its about 1/2" thick and holds its form pretty well.

 

[DayTrip]

The US military uses a dense foam for sleeping pads. They are cheap, usually the shipping is as much as the pad. You can pick them up at military surplus stores or on Ebay. I ordered a couple of them during covid and they go lost in the mail so the vendor shipped another 2. About two months later the original set appeared so I have plenty of foam in stock. Its about 1/2" thick and holds its form pretty well.

The gun case foam I was looking at is some sort of military spec grade and probably what I am going to use. I comes in a huge sheet though (I think it was 16x54 or thereabouts) so it was kinda pricey (The 1 in thick pad I think was $44 on Amazon. I get free shipping though). My existing pad is roughly 12x21 so I guess if I botch my first attempt I'll have enough left for a do-over.

 

[maineguy]

Foam specifications:

https://foamonline.com/foam-types/

 

[DayTrip]

Foam specifications:

https://foamonline.com/foam-types/

Awesome. Thanks.

 

[Lost Dad]

Closed cell polyethylene is a decent option. This is most likely what you are seeing in gun cases. We used it in tool cases for equipment that was shipped all over the US. I do not believe that you would need as much as 1" thick; 1/2" to 3/4" should do it. The stuff can easily be cut with a knife and if you want circles, a holesaw works wonders. You can also glue (hot melt glue) a couple of sheets together to get additional thickness in specific areas to customize the fit.

 

[DayTrip]

Closed cell polyethylene is a decent option. This is most likely what you are seeing in gun cases. We used it in tool cases for equipment that was shipped all over the US. I do not believe that you would need as much as 1" thick; 1/2" to 3/4" should do it. The stuff can easily be cut with a knife and if you want circles, a holesaw works wonders. You can also glue (hot melt glue) a couple of sheets together to get additional thickness in specific areas to customize the fit.

Yes this does sound like the type of foam I am looking at. An inch really isn't all that thick and I want to be sure if I poke holes in it the leftover mass is still sufficiently rigid.

 

[Breeze]

Hit up a discount retail store for a really inexpensive egg-crate mattress topper in twin bed or cot size. Measure and cut to fit, egg-crate to your back, and the ventilation need goes way down.

 

[DayTrip]

Hit up a discount retail store for a really inexpensive egg-crate mattress topper in twin bed or cot size. Measure and cut to fit, egg-crate to your back, and the ventilation need goes way down.

Interesting. That is really soft foam though isn't it? Will that provide support or were you suggesting purely for ventilation purposes?

 

[Breeze]

It's high density memory foam, IOW shape retention is a key feature. It doesn't slump under weight or pack down, the ventilation is a bonus.

 

[DayTrip]

It's high density memory foam, IOW shape retention is a key feature. It doesn't slump under weight or pack down, the ventilation is a bonus.

Excellent. Definitely going to check this out. Thanks.