Different kinds of springs and other info
Jan 30, 2010 1:14 PM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
http://en.wikipedia.org/wiki/Mattress

From the page above:

"Spring mattress core

The core of the mattress supports the sleeper’s body. Modern spring mattress cores, often called "innersprings," are made up of steel coil springs, or "coils."

The gauge of the coils is another factor which determines firmness and support. Coils are measured in quarter increments. The lower the number, the thicker the spring. In general, higher-quality mattress coils have a 14-gauge (1.63 mm) diameter. Coils of 14 to 15.5-gauge (1.63 to 1.37 mm) give more easily under pressure, while a 12.5-gauge (1.94 mm) coil, the thickest typically available, feels quite firm.

Connections between the coils help the mattress retain its shape. Most coils are connected by interconnecting wires; encased coils are not connected, but the fabric encasement helps preserve the mattress shape.

Here are five types of mattress coils:

  • Bonnell coils are the oldest and most common. First adapted from buggy seat springs of the 19th century, they are still prevalent in less expensive mattresses. Bonnell coils are hourglass-shaped, and the ends of the wire are knotted or wrapped around the top and bottom circular portion of the coil and self-tied.
  • Marshall coils are each wrapped in a fabric encasement and usually are tempered. In the case of Beautyrest, high carbon magnesium is added, while the steel itself remains untempered. Some manufacturers pre-compress these coils, which makes the mattress firmer and allows for motion separation between the sides of the bed.
    Bonell springs
  • Encased Coils or encased springs, are a component part of a mattress in which each coil is separately wrapped in a textile material. Encased coils may also be generically referred to as Marshall coils or wrapped coils.
  • Offset coils are designed to hinge, thus conforming to body shape. They are very sturdy, stable innersprings that provide great support.
  • Continuous coils Or Mira-coils, work by a hinging effect, similar to that of offset coils. In a basic sense a continuous coil is simply that, one continuous coil in an up and down fashion forming one row (usually from head to toe) of what appear to be individual coils. The advantages of how firm a support the continuous coil provides it is somewhat tempered with the "noise" associated from a typical Mira-coil unit. The largest company using a Mira-coil design, is Serta Mattress Company, though their coil units are supplied by Leggett & Platt.

Bonell springs are hour-glass shaped, which means their resistance increases with load. They are therefore best suited for firm mattresses. [my emphasis]

Pocket springs provide support along the entire length of the body. This design works to maintain natural spinal alignment throughout the night.

Re: Different kinds of springs and other info
Reply #26 Jan 31, 2010 11:15 PM
Joined: Dec 17, 2009
Points: 850
Simmons Beautyrest for a very long time has only been independent pocket coils.  In Beautysleep (not sure if that line existed in the US, its also done now as far as I know) was Bonnell coils for a long time, and they also did some continuous springs in their lowest end models. 

Sealy Posturepedic was a double offset coil since the 50's and more recently triple offsets, and some other small variations have come and gone, newest Posturepedics (last couple of years) could be offset or pocket coil. 

Spring Air....I honestly don't know.  That company to me is a little bit more of an unknown because they have changed ownership so many times and in my region they have never been all that popular.  So I couldn't tell you what they used back in the day.  Nowadays they use a lot of continuous springs in the lowest end product, bonnell coils in some limited quantities and some cheap pocket coils in some beds just above those in terms of pricing.  Although I have seen a lot of retailers selling the continuous springs as a big price jump over the bonnell units, I think thats just a big cash grab. 

In the whole industry the two most used coils that seem to keep on cropping up are in a queen size a 390 coil count bonnell spring that can come in quite a few different gauges of wire.  As well as a 720 coil count continuous spring...interestingly I think the bonnell is typically a much stronger and more expensive coil.  I can definitely tell you from my earlier days in this business working in a cheap discount schlock house I used to unload a lot of both of them, and the bonnell coils were a LOT heavier. 
Re: Different kinds of springs and other info
Reply #27 Jan 31, 2010 11:51 PM
Joined: May 3, 2008
Points: 827
Thanks for the info.  I thought you were too young to know, guess I was wrong.  But Spring Air was popular in the US here.  I thought they didn't start changing hands until 5 years ago.  They were changing hands before that???

I knew Simmons had the wrapped kind, at least when I went looking you can feel the difference on those mattresses.  I never thought those wuld hold up in the long run.  Do they?  Doesn't matter now though Simmons is gone, but maybe someone will revive them.
Re: Different kinds of springs and other info
Reply #28 Feb 1, 2010 12:10 AM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
budgy wrote:
no, I think I certain degree of understanding is required.  the problem is, every time they made changes they marketed them as being good for the consumer.  well once they started getting rid of cotton batting in favour of foams, then the only way to still sell a bed at 2 or 3 thousand (which they do offer in some cases) is to put more foam in it, which ironically makes for an even poorer mattress design.  i really don't wanna shift the blame where it doesn't truly belong, but consumers did keep on buying them right?  Its kinda like using your wallet to speak for you and say 'yeah I want a big thick pillowtop bed that looks like its worth 2 grand instead of a bed thats actually worth 2 grand'.  And of course we have uneducated sales people (or misleading ones depending on how much they really know) that tell people these beds will still easily last 10 plus years.  The other ironic thing with it all....especially with the really thick beds, there has to be a point where the innerspring itself would make virtually no difference in how you sleep because you could have 6" or more foam inbetween the sleeper and the spring system, at which point its basically like sleeping on an all poly foam mattress. 


That last sentence is just the point I was making to Leo, I think, about how sleeping on more than 3" of foam on top of my mattress - for me - negates the working of the mattress springs. I can see maybe going to 4" or so, in some cases, if it's good quality, but like you say, after that the springs seem superfluous.

Yes, of course they marketed the No-Flip as a great thing for consumers!
It's funny but people DO hate and procrastinate moving their bed! I procrastinate just rotating mine, so I know. But really, the companies knew these beds weren't going to last. But you are right, people bought them... But at the same time, look back on it:

Let's say all the S Co's have just changed to No Flip and you're Average Joe and Jane Doe walking into a mattress store. You have no reason to believe that the mattresses they are selling will be any worse than what was sold before and you had your last mattress for 20 years!

You buy one and after 6 months you start to notice some back aches and after a year you need to find a new bed. You decide to buy a different brand this time and you do and let's say that one lasts 2 years, this time... My point is that it took people at least 3-5 years - or more -  to begin "catching on" to the fact that these are poorly made mattresses! So it took consumers at least 10 years to catch up to the fact that ALL the Big S companies - who surely must account for 80-90% of all mattress sales, especially 15 years ago -  had now started producing inferior products.

Even now people don't know because many people are sleeping on beds that are 20 years old.

So when you say "People kept buying them", yes, because they'd buy one from one company and assume the next one from a different S Co would be better. Who'da thunk that EVERY major (S) company was now selling inferior products? Even I wasn't cynical enough to think that.

I bought a Simmons in 1997 or so and then bought a Sealy when that wore out... It took me a cycle of 2 bad mattresses before I began to suspect  there was something rotten in Mattress Land. And I had internet to research it and was inclined to do so. Go back to the 90's and not as many people had internet nor were inclined to use it for research like this.

So my point is, it took people a long time to realize the wool was being pulled over their eyes re mattress quality. Additionally all the salespeople - honest or not - were sayng this technology is better, this spring system is better, etc... so you figure "Oh, I see, those last 2 mattresses I bought used the wrong technology... this one will be better.  This time I'll spend more money, I'll get the $1400 one instead of the $1000 one..."

One more quick point: I talked to my friend today whose guest bed I slept on in December for a few nights. I really liked it but forgot to ask what it was. So today I said "I bet you it was at least 10-12 years old and it's a no-flip and it hasn't been used that much." He said, "Yes, it is about 15 years old, it was used by my wife for a few years and then it's been in here in the guest room since we've been married (12 years), so hasn't been used much."

I was telling him to take care of it and never sell it but instead fix it if it needs it because he'd never get another one like that.

He is a very sharp consumer yet was very surprised to hear that now everything is no-flip because he has not bought a mattress for 15 years. So you see - the point is, even now people can walk into a mattress store and have no idea how the quality has changed since their last mattress. So they'll buy one or two or three - before they even realize ...they're ALL bad.

By the way that great mattress my friend has is a 15 year old Spring Air! Ha! Now counted as the bottom of the barrel...
This message was modified Feb 1, 2010 by jimsocal
Re: Different kinds of springs and other info
Reply #29 Feb 1, 2010 12:31 AM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
Leo3 wrote:
I do blame the manufacturers mostly because of their greed and poor management, they no longer cared about good products or warranties, or even return customers. 

Not caring about return customers is the part that blows my mind! I can't wrap my head around a business that operates that way.

But then, I worked for a company for 12 years that cared not one iota for their employees. Their attitude - yes, actually stated verbally - was "we don't care if you stay or not; if you don't like it here, get another job". This was not just to me but to the entire staff. Unfortunately more and more busineses - almost all - are run like this now. Bottom line is profit, nothing else counts.

It's "the race for the bottom". Lowest price for a product or service is all that matters. People want to spend less.
In a way Budgy is right: we do keep buying the lowest price plane ticket and the lowest price this or that, even though it means less service, less quality, etc.

But for the companies, what about next year? Aren't they worried about losing customers or losing good employees, or ...?
Next year doesn't matter. It's all about making profit NOW. All that matters is the Almighty Dollar.

Huh?
I feel like I woke up to a bad dream.
What happened to this country?
What happened to companies caring about their employees? What happened to companies trying to make the greatest highest quality product they could? What happened to caring about the future of the business, the future of the employees, the future of the planet... our future?

Forgive me. I'll get off my soap box now.
Re: Different kinds of springs and other info
Reply #30 Feb 1, 2010 12:39 AM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
Leo3 wrote:
 This you might find interesting  http://www.epinions.com/content_2589958276
it is posted by a mattress developer in 2002 (still relevant)  that gives some insight to coils and which ones help/hurt a back, and why you back needs some cushion to fill up the small of your back to prevent lower back pain.  Be sure to look at the links page on consumersearch.com.


Thanks for that link. I bookmarked it and will get around to reading it sooner or later.
Re: Different kinds of springs and other info
Reply #31 Feb 1, 2010 12:44 AM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
Leo3 wrote:
http://www.beddingcomponents.com/innersprings.asp

This is from Leggett and Platt website.  Now can someone tell me which mattresses use what components?  On the right hand column you can download the .pdf on bonnell and Marshall coil.  I am STILL trying to find out what my Spring Air from 15 years ago has.  I think Bonnell obviously, but those are the firmest from what I understand.  I am not even sure if the bed manufacturers still are using these.  Who knows?

Leo that site used to be very informative but now it's about only their latest technologies and no, there's no way of knowing who is using what...
what a weird business the mattress co's are running! They go to the trouble of making what looks like a very informative site but it has almost no useful information!
Yes, Bonnell is still very much used, and my Englander is supposed to have Bonnell. I say "supposed to have" because I have never seen any printed info on what is inside my Englander. And I was told different things by different salesmen. But my best guess is they are Bonnell 12.5 gauge springs.
Re: Different kinds of springs and other info
Reply #32 Feb 1, 2010 12:52 AM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
Leo3 wrote:
http://www.beddingcomponents.com/innersprings.asp

 I am STILL trying to find out what my Spring Air from 15 years ago has.  I think Bonnell obviously, but those are the firmest from what I understand.  I am not even sure if the bed manufacturers still are using these.  Who knows?

I recall about 9 years ago when we bought our Sealys (BIG mistake!) that one store was trying to sell me a Spring Air that had "zoned" springs, I believe. Softer at the shoulder, firmer at the hips, something like that. I could be wrong, maybe it was the foam, but I'm pretty sure they showed me the springs.

That mattress my friend had that I liked so much was a Spring Air from 15 years ago. It's called a Majestic. But he had no info on the springs, only what was on the label. I guess the most important thing was on the label, though. It said, "Endorsed by orthopedic surgeons" ...

Hell, it was probably a very middle of the road bed back then but now it is probably better than anything you can buy without spending $3000+ !
Re: Different kinds of springs and other info
Reply #33 Feb 1, 2010 4:14 PM
Joined: May 30, 2009
Points: 9
If I remember correctly, 15 years ago Spring Air usually used a bonnell coil on their promotional coils. On the top of their line they used a368 offset 12 3/4 ga & then went to a 532 offset unknotted coil
Re: Different kinds of springs and other info
Reply #34 Feb 1, 2010 4:17 PM
Location: Yosemite area
Joined: Sep 10, 2008
Points: 249
Good thread, Jim;
From what I've gleaned, the main manufacturer of coils in america is L and P, and Sealy makes their own.  There are some independent spring makers but they typically only make the Bonnell units(ask Bill sometime...he gets specialty bonnnells).  There can be quality difference other than the type and gauge, depending on the processing of the wire...is it heat processed or electro processed?  That rearranges the molecules inside, can make the steel more brittle. 
Bill says that if a coil in a Bonnell  goes awry, it can be fixed.  Not so with continuous coils...the whole thing needs to be scrapped.  I think that was his objection to offsets as well, but I have to wonder just how often that happens.  But it must from time to time.
Wickipedia is a compilation of information gleaned from the internet, so it is just more sites rolled into one, not necessarily full truth.
Kait
This message was modified Feb 1, 2010 by Kait
Re: Different kinds of springs and other info
Reply #35 Feb 1, 2010 4:44 PM
Joined: May 3, 2008
Points: 827
jimsocal wrote:

But for the companies, what about next year? Aren't they worried about losing customers or losing good employees, or ...?
Next year doesn't matter. It's all about making profit NOW. All that matters is the Almighty Dollar.

Huh?
I feel like I woke up to a bad dream.
What happened to this country?
What happened to companies caring about their employees? What happened to companies trying to make the greatest highest quality product they could? What happened to caring about the future of the business, the future of the employees, the future of the planet... our future?

Forgive me. I'll get off my soap box now.

I agree.  I was still trying to read about Spring Air history to see where they went wrong.  You can't find much except twice now it has done chapter 7 and/or 11, and at "Furniture Today" website I found an article on how not to close a plant, regarding how Spring Air put a letter on the door and the employees came into work to find no job, no health care, and no Cobra options.  Nice huh?  A CEO and VP (I think) sued for severance pay (this was the first bankruptcy) and won.  A former employee (recently) is suing Spring Air because you are suppose to give 60 days notice for plant closure.  Hope they get some justice.  I feel really bad for employees nowadays, we get a really bad deal.  This in turn gives consumers less choice and probably higher prices, no competition the companies don't have to have good prices anymore.

Maybe this will make smaller mattress companies succeed, if they make a good product.  Not many people will choose these S manufacturers that keep filing chapter 7/11 and selling to another company and then another......

Off soap box now.

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