Upholstery and Fabrics - Redesign/reupholster old rocker

I am trying to update an old beat-up rocker, which has some sentimental value for my wife. I am guessing it dates from the 20s or 30s.
The area where you sit is close to a box shape. Originally it had 3 metal straps whish sort of dropped down in to this box shape, and each strap had 3 coil springs attached to it, then the stuffing (which looked like hay or horsehair surrounded by cotton batting) went on top of the coils (yeah, what a mess after this many years!) and uholstery (ugly green vinyl) went over that.
It has been recovered with that vinyl and probably at least one time before that. Last job was a real poor attempt, I can't even visualize how it was originally done.
The rest of the chair has some problems I hope I can fix up OK, or at least have the foresite to know when to leave "good enough" alone with this thing.
SO. What I need from you all is this:
"WE" have decided that it will be OK to just forget the springwork as being too tough to try to work with, especially in the upholstery fabric phase. I bought a 2'X2' piece of 3/4" oak plywood and have trimmed it up to fit on top of the box section. Now I want to recover it. My wife will want to use it (luckily she is a small person). What would I want to use to pad the seat, taking in to account I would like her to be comfortable in it? I am thinking a thinner layer of something rather dense on the plywood itself, maybe 1/2" thick, then working up to something thicker and not as dense?
I do have some reupholstery experience now, mostly car stuff and a small padded bench (similar to a piano bench), I do seem to have a knack for it (ends up looking good), but wanted to know what padding materials I should use to make this really comfortable for her.
Gilly

I would think firm foam, at least 2 inches thick with a layer of bonded dacron over the foam.

Thanks Moose, I have been on a short vacation (since Sunday). Is the Dacron something one would use instead of cotten batting? Should i be able to find it someplace like an upholstery shop or a fabric store?
Gilly

I would get medium to medium firm foam but high density. Firm foam may get a little hard feeling if you want something soft. The bonded dacron won't tear but you can use an upholstery batting. You can use regular batting but then you'll have to use more layers. Depends on the thickness of the batting.
Some fabric stores may have this and some won't, but don't buy the foam from Joann's Fabrics. An upholstery place would be better, then they can help you with the selection.

Uh oh, I bought the material (cloth) from Joann (it is upholstery cloth). What's wrong with their foam?

Gilly

The fabric they sell is fine, it's just the foam is cheap junk.

Well, against Shadeladies' advice, I had no good option when buying the foam, sooo, JoAnns is what I got. Supposed to be 2", I measured it at 1 3/4". Got it together and really looks nice, I am posting a picture.
Problem though. It's too thick, the seat is too high for my wife. So I have to redo it. I guess I can reuse the batting (I did get polyester, so I DID listen to that), and the cloth.
So.....where in particular would I find "good" foam (she also says it's too firm, is that a characteristic of JoAnn's junky foam? JoAnns did refer to it as "firm" or something like that. I guess I can't complaint too much about JoAnns, main problem is I need something less thick.
http://lh3.ggpht.com/_YbsV635_ofk/StUGocdsnOI/AAAAAAAAAjM/RVh_09YFLPA/s640/000_1429.jpg

Perhaps Joann's is supplying better foam now (it's been some time since I bought any there), but for comfortable sitting you want medium rather than firm. 2" isn't that thick, but I guess you'll have to go with 1" which may be somewhat flat, yet I'm not sure if 3/4" will make a big difference. Another option might be to use a down cushion rather than foam.
Try doing a search for "upholstery supplies" to see if there's a place near you.

Thanks much for the reply, even though I went against your better advice.
I was off on the thickness, I used 3", it measures in at about 1/8" less than 3" though. My wifes feet won't even touch the floor when she's in it (she's only 5' 2"). I glued a layer of the heaviest poly batting they had on the top of the seat, under the foam(they had a weird number system for the weight of it, I want to say it was #5 or maybe higher than that, but the highest number, quite thick). Then the foam, then an overlayer of the same batting, then of course the upholstery material.

My thought is this. Back to JoAnn and get something significantly thinner, like a 1" foam. The batting that is glued down I want to leave in place. OK, then the 1" foam, then a sheet of the batting, just on top of the foam, then the overall cover of batting, then the upholstery material. So total of 2 layers of poly batting over the foam. Of course NOW I am going to get my wife more involved in this because I only want to do this ONCE (OK up to TWICE now:rolleyes:).
She thinks it's too hard (firm) in addition to too tall, I am afraid that if she sinks too much it will be like sitting on the board underneath, no cushioning. JoAnn has "high density" on the price sign, seemed to apply to all of their foam.
Thanks again, you're great.
OH 2 or three other ideas (if you think I should just get some better foam and stick with one batting layer) we have a "Michaels" in the area (arts and crafts chain store) and also a Hobby Lobby, a couple people have mentioned them as a source, or what about a "Verlo" store, they probably have some stuff they'd sell.
Gilly

On the double layer of that thick batting(plus the layer between the board and foam), my thought process is the batting will make it comfy, but the inch of the high density foam would make it unlikely that it will ever feel like she is actually "on the board" underneath. That's my thought anyways, maybe I am going against conventional wisdom, but 2 different materials to do 2 different things.
Gilly

I am really proud of the way it looks anyways!:thumbup:

Yes, it does look nice! :D
3" is pretty thick, but 1" can look like a pancake. I would use 2" and just wrap once with the batting (if it's 1/2" thick). If you feel better using 1" and it's too flat, you can always add another piece of the 1".
I don't know what the #5 means. Foam's are very different depending on who makes it and where you get it. You want a high density foam no less than 2.5 (meaning better quality, will last longer, and won't squash and buckle) and a medium or medium/firm compression (meaning a little softer feeling).
I really don't know what kind of foam these stores are selling. You might want to ask someone that works there if they can explain their foam a little better.

The number system was for the batting, the higher the number the thicker it was, and this was the thickest, but not 1/2", it is probably less than 3/16" I'd guess? I am also guessing the number might reflect the weight? I have seen other things where the thickness or quality of something is expressed by a pound number, like the black paper they use under shingles on a roof. I thought it might be like that.

Gilly

I redid it, using some foam they had at Hobby Lobby, some stuff called Smart Foam. It isn't a "real" foam, more like the poly batting I used, but 2" thick.
Wife is much happier with it now.
Will post final pics, thanks for the help everyone.
http://lh6.ggpht.com/_YbsV635_ofk/SueM4ysfyrI/AAAAAAAAAkA/-NLP41QLR8c/s640/000_1470.jpg


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