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 #16 Jan 31, 2010 1:15 AM
Joined: May 3, 2008
Points: 827
jimsocal wrote:
Did some searching on the net and was shocked that there are really no sites other than wikipedia that go into the differences in inner spring types. L&P's own site now just highlights their newest springs, it doesn't even talk about Bonnell, offset, etc. any more... I think they USED to have a good page on the most common types of springs...

Anyway, this is the ONLY other one I could find that talks about various innersprings:
http://www.consumersearch.com/mattress-reviews/innerspring-mattresses

I haven't even read it yet, I just glanced at it and put it here so I can look at it later.

Thanks for the link, I just read it all and then clicked on the links and read some more.  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.

Also after reading what consumerreports.org reviews are based on is pretty lame.  They only tested the mattress for a month.  Now we all know that the mattresses take a few more months for the foam to break down and those indentations to form (though memory foam does not show the holes, but you feel the breaking down of the foam).  So they also don't make recommendations.

Lots of good reading material for a sleepless night to make you fall asleep, LOL.
Re: Different kinds of springs and other info
Reply #17 Jan 31, 2010 1:56 AM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
budgy wrote:
"Budgy, can you comment on how and when this happened?"

In my opinion the major companies are actually in a heap of trouble and I think it is primarily because this has happened.  Industry content warning, rest of this post will be more about business.  The value of the major S brand companies is in a major downward spiral recently.  This is partially due to the recession.  But in reality this is a cop out, Simmons was the first company to go to non-flip mattresses...initially it was done only on their 'high end' mattresses.  Of course in reality this was marketed as a new special technology and was done to reduce motion transfer and magically you never had to flip your mattress anymore, although if it really cost any more money to build a mattress this way why on Earth would it eventually trickle down to even the most basic mattresses they made? Pretty obvious really.  Of course other major companies quickly followed suit because this feature was being sold against their products and didn't want to lose sales to this.  We in the industry were also told that the 'stress tests' that they ran on the product actually showed the newer non-flip mattresses stood up better.  We know now after a few years of selling this stuff that this is obviously not the case.  This is one of many things that has been done over the last 30 years to keep the prices in check. 

Believe me when I say that quality cutting actually started longer ago than you may think.  I want to give you some unique perspective.  I personally think from my end that todays average consumer may not actually think a good mattress is truly worth what they cost today.  I am gonna use Simmons as another example.  Back in the 70's they were still using cotton shells for the pocket coils, the mattress came on a proper coil 'boxspring' instead of a coil base, they were upholstered mostly with cotton and wool batting, had good quality cotton damask covers, they were fully reversible and they all last 15 years on average.  Heres the thing....back THEN a good quality beautyrest like this actually cost somewhere around $1000.00.  A 'good' Beautyrest today still only cost $1000.00 (give or take a couple hundred) after 30+ years of inflation.  Spending $1000 on a mattress back then is like spending $3000~$4000 on a high end sleep set today.  These companies have gotten so large that in order to keep the factories running full tilt they need to churn out a lot of mattresses.  So in reality they have all been racing to the bottom (of price) for decades.  And in the process they have set up a completely unrealistic expectation for customers to think they can get a top of the line queen bed for a thousand bucks.  Problem is a top of the line bed from the same manufacturers today @ $1000.00 is just not made even remotely the same way.  Now that these companies have already completely devalued their own product it is actually way too late for them to go back to the way they used to build them and charge what they use to charge.  Don't expect it to change for the better, expect it to stay the same until these companies run themselves into the ground. 

We have been told that mattresses being replaced quicker and quicker is great for us in the sales aspect, we started our company based on the philosophy that in reality if someone buys a $1000 bed from me and it lasts 5 years they will never buy from me again, I really don't care if its good for the industry, I care what is good for myself and good for my customers.  I want them to spend the same basic money lets say instead of buying a $1000 bed and it last 5 years, its my goal for them to spend 2~5 thousand on a queen, have it last 15~25 years, have the best sleep of their lives and recommend all their friends to come see me as well.  To me this is a win-win, and the manufacturers don't really seem to understand this basic concept anymore.  Or they have a delusional view of how good their product is if they honestly think these people will buy from me again. 
"Fascinating..."

That is kind of how I thought it happened. One followed another into this mess...

As cynical as I am about the Big S companies, I still have to ask:
Is it possible that they were in a way economically "driven to using cheaper materials" in order to keep the price low enough for the average consumer to be able to buy a "great" bed? Perhaps they figured that since it was starting to cost $2000 to make a great bed, they started looking for a way to make them cheaper? And in so doing, they also of course had to make them last less time...

Seems to me that the mistake they made was in not continuing to make great beds at $2k and $3k, so they had something to "sell up" to. And perhaps if they had marketed those higher priced beds, each company could have had at least one truly good bed in their line? But then, if they couldn't sell enough of those beds at that price, they would have to make less of them which would not achieve a proper "economy of scale".... so they let that end of things go...

Or am I giving the *&%~|\'s way too much credit?
Re: Different kinds of springs and other info
Reply #18 Jan 31, 2010 1:11 PM
Joined: Dec 17, 2009
Points: 850
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. 
Re: Different kinds of springs and other info
Reply #19 Jan 31, 2010 1:54 PM
Joined: Oct 15, 2009
Points: 966
Budgy, you make a good point about what a mattress should cost now adjusted for inflation.  If they use to charge $1000 20-30 years ago for a quality mattress, it probably should be at least $2,500- $3,000 now.   I can't remember what I paid for a Sealy Posterpedic 22 years ago, but I think it was around $700-800.  It was definitely constructed better (and heavier) than the stuff they put out today.  It didn't have much in the way of wool or cotton padding though, so I assume a better more comfortable one back then would have cost even more.  It seems like you have to buy from a smaller brand now to get a quality product and avoid the junky foams. 

The mattress industry seems to have gone the way of some other industries like the airlines.  They are in constant competition to reduce costs and show cheap prices.  As a result, they have degraded their "product" over time. Consumers contribute to this some what, because they will generally take the airline that has the cheapest cost, even if their service is worse.  However, one can put up with a few uncomfortable hours on plane, but having 8 hours of misery every night it a totally different matter.  Will consumers wake up and start demanding a better product (by not buying the junk)?  Maybe most are getting by okay, and don't want to spend the extra money.  However, if they have to replace the mattress more frequently, they are not really saving money.

A friend of mine might be in the market for an innerspring.  I told him about the Royal-pedic, and he seems interested in that.  Are there any other brands that you recommend in the U.S. that are "reasonably" priced?

Re: Different kinds of springs and other info
Reply #20 Jan 31, 2010 3:06 PM
Joined: May 3, 2008
Points: 827
budgy wrote:
  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. 

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.  Yes consumers kept buying them, I think they kept trying different brands thinking this brand has to be better. I never fell into the trap of big pillowtops, but it was increasingly difficult to find any decent mattresses at all.  Okay I fell for the gimmick of Sealy Truform, I confess.  If it sounds too good to be true it is.  But I never tried anymore memory foam and foam mattress combinations.  Nor would I put latex over foam.  Okay I turned the Sealy Truform over and put latex toppers over that; it didn't work!  The foam broke down, never ever will I use regular foam again as a base.

The internet has helped consumers GREATLY because reviews are out there now for all to see.  They can't hide their poor products anymore, but now it is too late.  Selection is bad because companies are closing doors. Smaller companies may prevail in this economy, time will tell.
This message was modified Jan 31, 2010 by Leo3
Re: Different kinds of springs and other info
Reply #21 Jan 31, 2010 3:06 PM
Joined: Dec 17, 2009
Points: 850
in the coil mattress segment...nope.  they seem to be the best overall value for the money from what I have seen.
Re: Different kinds of springs and other info
Reply #22 Jan 31, 2010 4:54 PM
Joined: May 3, 2008
Points: 827
I have to say after further research I found Simmons filed chapter 11, and than I find an article they have new mattress line.  I read they have kept changing hands over the years.  I have read that about Spring Air too.  So are their any mattress S companies that have not filed chapter 7 or 11 or whatever?  Are any of them really the original owners?  I doubt that.  Why does this never make the news?  I have stopped watching the news because it really isn't news.
This message was modified Jan 31, 2010 by Leo3
Re: Different kinds of springs and other info
Reply #23 Jan 31, 2010 5:13 PM
Joined: May 3, 2008
Points: 827
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?
Re: Different kinds of springs and other info
Reply #24 Jan 31, 2010 6:48 PM
Joined: Dec 17, 2009
Points: 850
a 312 bonnell coil from leggett and platt is used by probably over a hundred small manufacturers in north america
Re: Different kinds of springs and other info
Reply #25 Jan 31, 2010 10:50 PM
Joined: May 3, 2008
Points: 827
Thanks Budgy, so are you saying Spring Air USE to use Bonnell coils?  I guess it doesn't matter, but I am so darn curious now.  What was common for the S manufacturers 15 years ago?  I believe Simmons used the wrapped coils, Marshal coils I believe. But then I see it could be hinged springs.  Do you know what they used back then?  You are probably too young LOL, to know.