3½ years on my custom emperor mattress - a retrospective

I made a 7'x7' mattress that I've been sleeping on since mid 2018.
It's October 2021 now, so I've been sleeping in it for about three and a half years. This retrospective will cover my findings from worst to best:

This was clearly the biggest weakness with my project. When I finished my mattress, you could see the zigzag patterns along the buckling column gel comfort layer. It did not look like a professional mattress that one would purchase.

On top that, within a few months, the top of the gel sort of recessed in a bit so I lost about an inch on every side. Part of that is because the buckling column gel sheets were 4'x4' so I had to cut down three out of four of them to get to 7'x7', and I'm sure I dind't make perfect cuts. But even the corner of the one gel sheet that remained at full size curved in a bit. Luckily, this trend did not continue beyond that initial shrinkage within the first few months.

More on this later...

The loss in score comes from the previous issue with polish. Otherwise, the mattress has remained firm, there are no indentations from sleeping, the materials have not degraded, I do not notice where one buckling gel sheet ends and the next begins, and no connections have broken.

"You chose the size! How was this only 8.5/10!?" you ask. Let's break it down:

width - 5/5

The width has been perfectly fine. Even with the slight regression of the comfort layer, 6'10" width proved to be enough, noticeably more sprawling space than the 6'4" of a King sized mattress which would only give me a couple inches past my wingspan. Sometimes my girlfriend would slowly inch me over to the edge of the bed or vice versa while we slept, but doubling the width would only delay that process...

height - 3.5/5

No, I'm not 7' tall, or even 6'10" or anything close to that. But if I want to lie chest down on my mattress, with my toes pointed downward, with my hands and forearms above my head at an angle, perhaps to use a phone or laptop or simply to hold a pillow, that length is greater than 7 feet, although still less than 8. Honestly, I should have predicted this, the King and Queen mattresses are already 6'8", so I only added 4" (which collapsed down to about 2"). I am able to do this diagonally but it's not quite the same.

other thoughts on the size

Other mattresses look tiny to me now! Also my roomba would sometimes get stuck deep under the bedframe and getting it out was a challenge.

When I originally planned to just buy a mattress, I really didn't have comfort in mind, just size. But I'm glad I ended up researching materials and making this myself. This is by far the most comfortable mattress I've ever slept in.

Temperature-wise, the cooling caused by the gaps of the buckling column gel, on top of the latex with small holes throughout, on top of holes I put in the bed frame makes this sleep very cool, which has always been an issue for me.

Support-wise, the buckling of the gel provides support sitting, lying face down, lying face up, lying sideways, and so on.

It's a weighted average! Overall I consider the mattress to be a resounding success.

The three flaws are lack of length, visible buckling gel edges, and shrinkage of buckling gel along the edges.

All of these could be fixed if I were to make a new bed. Rather than cutting the buckling column gel sheets to make it 7'x7', I would simply make the main latex core 8'x8' and put four sheets on as is for a matching 8'x8' total. This would solve the size issue and part of the shrinkage issue. After that, I would add 2" more of latex on the four sides at the full height of the core plus the gel and attach the gel to these edges in addition to the core. This would solve the remaining shrinkage and the visible buckling gel edge issues, leaving a solid 8'4"x8'4" rectangle to be put in an encasement like so:

Looking back now, having side foam is incredibly obvious, but alas! In theory I could attach some latex foam on top of the existing latex core and attach the gel to that foam to get the solid rectangle like in the above diagrams, but honestly I would have to take so much of it apart, squish it together properly, and then reattach it that I am not inclined to do so. I'm also not entirely confident that the smaller foam strips would hold as well as entire sheets of latex foam attached from the outer edges.

Am I likely to actually build another mattress? Not in the next few years. But if I were to move to a place with a larger bedroom and a guest bedroom for my original mattress, then yes.