Frame for “frameless” pack

What about instead of just cutting the pad in half you cut it like a puzzle piece. 5 or so male ends on the bottom half. 5 or so female ends on the top half and it will hold itself together without adding any weight.

Using CCF(Closed Cell Foam) pads for a frame is an old idea and a good one. You make a good point about two pads being needed to stiffen a frameless pack. The buttons you mention are really no heavier than using a bunch of duct tape to hold them together in use as a pad. The symmetrical loading of two stiffening members improves the ”tube style” of rolling inside.

The basic technique of using duct tape (DT) and CCF works quite well, at least till the tape dries out. This happens after about 4-5 years. DT sticks quite well to CCF. The entire pad, being fairly water proof and maintenance free, is not prone to punctures and leaks like inflatable or self-inflating pads.

The thickness of the pads can be a problem. With thin 1/8” or 1/4” pads, you can loose the overall effect of stiffening. Multiple layers of thin pads do not have the same stiffening effect as a single layer of a thicker 1/2" pad, nor the same warmth. Some textured pads provide pressure reliefs for lofting of a bag. Z-Rest, Nightlite, and some other pads provide additional warmth when used as a pad but sacrifice some stiffness when used as a frame. A Nightlite pad, for example, can interlock which adds some stiffness back when used with more than one layer, and, reduces volume from 3/4" for a single layer to about 1-1/8" for two layers…not the expected 1-1/2".

So, at last look at this method there were several variations that can be employed.
1) A simple rolled up tube.
2) A flat “fanfold” pad
3) A pair of smaller tubes as Eric describes.
4) A shaped stiffener pad

Of course, various combinations and reorganization of the basic shape you can cut and tape a CCF pad into. Longer pads mean more layers to a basic 20” pad. Often a 25” width is more dictated by the height of your pack, but is doable with most packs. All but the XUL or SUL packs being tall enough in most instances, even if it means extending into the collar, some.

Here is a basic diagram of the basic shapes:

A photo of the twin tubes "frame" would be great. Thanks, Scott

I think this would work quite well Eric. Only problem is 20" is too short for a lot of folks, especially if you want the frame to extend up enough for load lifters.

One of these size large? Would five inches help?

If I understand Eric's idea correctly, how about this way then ?

The rolls are kept in place by some improvised clips (bent coathanger wire)
Franco

A few posts up you mention 20" isn't tall enough for many people, and I agree. I'm thinking that, for instance, with a RidgeRest Solite Small at 48×20", a cut up pad would make two rectangles at 24×20". Instead of rolling the "short" way to create 20" tubes, why not roll the "long" way to create 24" tubes? If this is too tall one could snip off an inch or two on the pad until it was the correct length, at minimal cost to the functionality of the shorty pad.

I use the RidgeRest as an example of a common size pad (which I own). I'm not sure that the ridges themselves would take kindly to this rolling orientation…just an idea.

The OP's double-tube idea is very intriguing.

Perhaps Franco's suggestion of NOT cutting the pad (say a RidgeRest regular) but rolling it from both ends would work well. It's worth a try before going the more complicated route I suggested. Simpler is often better.

(Remember guys, I'm definitely of the "internal frame persuasion" so I won't be actually trying any of this.)