Monday, October 27, 2014

DIY: Cutting a Memory Foam Mattress

Maybe you're like me and you have something like this just lying around your house:

A giant, king-sized memory foam mattress with a chunk missing.

The chunk that our anxiety prone dog "ate."
No? You don't have a giant memory foam mattress with a chunk missing just lying about in your home? What?!  

Well if not, keep following along anyways, because I'm going to tell you how to cut memory foam, and this work on regular foam too.

Tools needed: 
-Ruler / Tape Measure (straight lines are important)
-Electric knife, such as this one that I bought from Wal-mart. It's also available from Amazon here.  I actually had to go back to the store and buy another one, because the mattress was so thick it dulled the first one when I was almost done. But if you're not cutting something so huge, you should be fine with one! 

To begin: 
I started by propping the bed up against the wall and drawing a line where I wanted to cut.
I was going from a king-sized mattress to a full, and taking off that unsightly chewed-up chunk with it.

I looked up the dimensions of the bed and decided to just cut a 26 in piece off of the length, since the width of a king and the length of a full are only an inch apart. I was going to cut a bed that would be 54 in x 76 in when finished and I figured I'd just stretch the sheets to fit. I was not going to attempt to cut one inch off the whole mattress. That would have made a bigger mess and at this point, I was have a bed frame and bunky board delivered the next day, so I needed it done now.

Dimensions of king bed: 76 in x 80 in
Dimensions of full bed: 54 in x 75 in

Dimensions of my new bed: 54 in x 76 in

I used a permanent marker and a tape measure to draw the cutting line (I had to do it on both sides.)

Plug in the electric knife (I used an extension cord because the cord on the knife was incredibly small) and take off the safety. Hold the knife straight up and down and just push down into the foam and it'll cut.  The straighter you hold it, the straighter your cut line will be. 

I am not good at following the lines.

Hello in there! 

Since my foam was really thick-like 12 inches or something- (and actually consisted of 2 layers), I had to cut it from both sides. I peeled apart one side and tried to cut the other side through it, but that was really hard to do because the foam was so heavy.  In the end I cut off the top layer and then measured the other side on the back and cut from the back.

Halfway done! This is missing the top layer of foam on the right side. 
Close up of the top layer missing. I had to get a step-stool to stand on while cutting because the mattress was so big.
You can see part of where the dog chewed up the mattress too.
Then I just continued cutting down the side of the mattress until I was all the way through. I am going to put the cut edge towards the wall, so I'm not too concerned if it's not cut super perfect. 

Cutting the big mattress actually required a bit more strength than I thought it would, mostly because the bottom, thick layer of foam was really heavy. And quite big.

Here's a before and after:

I ended up cutting the top layer of foam into pieces and my eventual idea is to make floor pillows out of them. I used the big bottom piece as a buffer between my 2 year old's bed and the floor.  I also had her sleep there for awhile when she didn't want to sleep in the crib, but the queen sized extra bed we have seemed too big for her. It was actually a perfect size for a little girl to snuggle up and sleep. 

I was going to just have the mattress company take the cut off pieces of mattress away when they delivered the frame and bunky board, but they told me they couldn't take just part of a mattress.  When I told them what I had done, one guy was like, what?! And the other thought it was a pretty genius idea. A bunky board, by the way, is basically a big covered board that goes under the foam mattress, so it doesn't seep down into the frame. It needed something to sit on while on the metal frame, and this did the job.  I only got a plain metal frame, since this is our guest bed and sits in the girls' playroom; I didn't want to invest in anything fancy.  
See? It's just a little bit over, nothing I'm worried about!

And that my friends, is how you diy a king-sized memory foam mattress into a full-sized!  I hope this helps any of you out there who have a damaged memory foam mattress and don't know what to do about it (that's got to be, like, 5 people, right?). The mattress delivery people said that I could call the memory foam company and get a new cover for the mattress, but since we got it for free from a friend, I decided to just cover it with a mattress pad cover underneath the sheets. It's been working really well for us too: lots of extra space in the playroom and my parents appreciate that the bed isn't on the floor anymore. :)




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