Walmart is arguably the most popular place to purchase an inexpensive air mattress. You can purchase a twin for less than $10 and a queen for no more than $20. But is it worth it?
That is what we are going to be discussing today and the short answer is, yes, it is well worth it. Let’s first address the problems:
- The air mattress is easily punctured. Yes, almost anything on the floor or ground will puncture them. Your pet will also send the air freely flowing out of your newly purchased air mattress from Walmart. You now have plastic that is rendered worthless to sleep on.
- Over time the stresses on the air mattress will cause the seams to burst. This also makes the air mattress unusable.
- Plastic stretches and it does not stop stretching. For those that are interested, the engineering principals for “stretching” are as follows:
Strain – ε
Strain is the “deformation of a solid due to stress” – change in dimension divided by the original value of the dimension – and can be expressed as
ε = dL / L (1)
where
ε = strain (m/m, in/in)
dL = elongation or compression (offset) of object (m, in)
L = length of object (m, in)
Stress – σ
Stress is force per unit area and can be expressed as
σ = F / A (2)
where
σ = stress (N/m2, lb/in2, psi)
F = applied force (N, lb)
A = stress area of object (m2, in2)
And the Modulus of Elasticity (E) is a function of stress/strain. Strain is a relationship of elongation divided by original length. So the larger the strain, the lower the E value, meaning more elongation or stretching.
For PVC (plastic in an air mattress, plasticized) is between .0001 GPA and 1.8 GPA for the E value. Take for example Nylon 6, the E value is between 2 GPA and 4 GPA. The stretch resistance between the 2 materials are on a factor of multiples.
Why go through all this? In short, use a material that resists the stress/strain relationship and have the air mattress function to simply hold the air. So let’s touch back with the problems inherent with Walmart air mattresses and for that matter, any air mattress.
- The holes. A cover obviously will help protect against holes.
- The seams blowing out. We’ve covered how an exoskeleton cover will resist most of the stresses all through our website and the basis for the calculations are shown above. Keep in mind the entire mattress must be encased. Any portion of the air mattress not covered will blow past the cover confines and eventually fail.
- The stretching. A six sided soveiluften cover prevents the stretching and the engineered reason is discussed above.
You do not want to purchase a Walmart air mattress every time you plan on going camping only to find out the second night you end up on the hard ground. You may have to buy multiple mattresses as a pre-caution or even pony up and spend 10 times more money on a more expensive air mattress. What you will realize is ALL air mattresses will have the same problems. You will end up with the same issues and simply spending more money.
So the recommendation is to purchase the inexpensive Walmart Air Mattress and protect it with our Soveiluften Cover. You will never purchase another air mattress again!
