Technical Let's talk about seat foam

In my avatar I cut down a Dodge caravan seat and used the same foam - my ass has sat on that seat for many, many miles.
In my old 40 Ford coupe I removed all the springs from the stock seat bottom and back, put a piece of plywood over the bottom/back openings and used sone thicker, softer foam first than sone dense cell foam like a yoga mat on top that was bigger than the cut of the under foam. I salvaged the old seat covers, having taken them off carefully, and put them back on nice and tight. This worked great for the 15 years I owned the car with plenty of loooong road trips.

In my present 32-5window with a stock seat I will be doing the same thing as my coupe. The trick to remember is the leading edge of the seat needs to be about an inch higher than the rear portion, giving you support under your thighs - your ass AND legs will love you for it …..

Btw - cutting and shaping the foam with an electric carving knife is the best way to cut it as has been said ……

 

The old ways, springs in burlap "socks", a layer of burlap, a layer of horsehair, a layer of cotton. Some pleats were stuffed with cotton or horsehair held in by ducking (linen) which was dependent upon material. Leather liked horsehair and wool liked cotton in my experiences. Cotton padding will move over time and make it look like a sack of potatoes so later on some cotton was bagged in linen as well. We cheated a bit in restoration. We finished with a nice quality ½" firm foam to maintain shapes over time and keep the cotton from bunching up.

But this is hot rod stuff so maybe this history shit is just brain food.

 

Here's the seat bottom in the Zipper. If you look closely at the seat back in the avatar photo, you can see a built in lumbar support. I depend on the guy doing my interior to get the right roam. So far, so good.

 

Steel is real.
Not much lower back support though.

 

This is how my mg seats were done for my model a

 

And a band saw.

 

I agree, a suspension base is best. That flat strap looks great. I recently bought some heavy duty lawn chair webbing and special screws. I need to re-do the seat bottom in my coupe. I don’t think it was engineered to carry the load of my fat ass.

 

Interesting thread. I'll be facing a seat rebuild in the not too distant future, so I'm keeping an eye on this one

 

Here are my bases I have to work with.

 

I've seen bench seats out of vans on Craigslist for free occasionally, how about picking up something like that and take em apart to use the materials?

 

What is the finished (look) design you are after. It will help with choosing foam.

 

That's the way Hot Rods used to be built, donor parts.

 

A lot of the mini van bench seats have the fabric glued onto the foam and it is almost impossible to get it off without destroying the foam.

 

I guess that's a good reason not to do it, then

 

When I had the interior done in my 50 Olds nearly 30 years ago, the guy stripped down my original seats, and said, "I can't get you foam as comfortable as this". It was in great shape, so he used it.

 

They are good for the frames. It's what I used in my truck. They are simple and easy to modify.

 

I used a minivan seat in the Produce truck.

. It’s ok for around town but it was designed for a kid hopped up on Red Bull and pixie sticks jumping up and down.

Not a fat guy driving across the state. My back starts to hurt after about 45 minutes.

 

Testing an repeated mock-up is time worth doing.
There are a number of good foams,and many from hard to soft,closed cell and open.
Typically a good foam seat bottom* is really two layers,about 3 inchs of very stiff,topped with a 1 inch soft topper/glued an cut to shape. On a baseboard.
This set up canbe used best if sitting low in rod is needed. To be comfortable an see out as you should.
Any rod that is not comfortable,no matter how cool you think you look in it,will over time be not driven as much<< that is fact= Stop bull crap { about,but I look cool in over chop,or with a super low windshield BS,and make it as comfortable as you can. It will be far more fun !! As for me,I like bench seat best,with a nice feel.

 

Necessity- and there being more than one way to skin a cat - is the mother of invention. Some great ideas here …..

 

THIS^^^^^^^^^^^^ is how to do a roadster. No reason to use springs these days. I am even doing my 51 GMC this way, modern tech and covering it with a more trad fabric/hyde pattern.

 

Thats a great base to start with

 

I bought foam for my Furd F100 project to build the seats from a bare frame. I used "Firm" 3 inch thick for the seat bottom, and "medium" density for the back. Amazon. Not super cheap, but not over the top expensive either.
My current set-up is a bit of an experiment, so I'd imagine I'll do 'em again sometime in the future. When I do, I'll use "extra Firm" for the bottom. The Firm feels good, but you do sink into it quite a ways. Kinda like a comfy sofa. Personal preference I think. But I'd prefer a firmer base than what I have.

 

Hello,

We had some foam cushions replaced with foam that was more dense and the upholstery shop said this was the next level of firmness. Seats in any chair or car seat will crush with the weight of the person. Constant usage will leave dents in the seat surface. The firm or dense foam will stand up to a lot of weight, with the addition of the material for seats. The cost is relative.

But, preparation of the supporting springs and straps is a must. Well, for that matter, so is the style of seats. Non-adjustable seat backs won't be as comfortable as fully adjustable units. Just because the Detroit factories have almost 90 degree seat angles, they are killers on long distance road trips. The more adjustments there are, then different drivers will feel nice in each set up car or hot rod.

Do you buy pants that are used for many years, stretched out and shapeless or spend money to buy new pants for all situations? What you use is a reflection of you and your tastes. Cheap or used foam is useless. One piece new foam, regardless of cost, that is shaped well, is much better than stuffing old foam on top of old foam.

A local foam reseller and upholstery shop helped us get a custom shaped foam piece cut and fitted for a unusual shape for a seating arrangement for our current house. We had the measurements and a pattern. They showed us various thicknesses of foam and the benefits of each version. We selected the medium range foam. The soft version was too soft and the hardest version was like sitting on a rock. So, like “Goldilocks,” the middle firmness was just right. But, it was a custom seating foam pad and cover used only for big time gatherings.

A car seat is used daily? Or at least not being a garage queen, used at least several days a week, rain or shine. The foam may need to go up one notch in firmness to keep the big body fitting well. It should not just crush from the extra weight put on it each time a ride to the store or long cruise comes up in the activities. The upholstery material helps keep the shape, but it too, will crush and show wear with constant use.

Jnaki

We just purchased a new custom made sofa. We got the extra firm foam inside. The cushions of any seat, let alone a sofa that anyone sits on daily, will get soft and crush over time. The weaker foam will crush sooner and the cost of replacing the foam is now in the upper end. The seats now become uncomfortable and movement to find a comfortable position is noticed when people constantly move around on the seat cushions. When you have the extra cost firm foam in the first place, the cost was higher. But, who cares, it lasts longer and feels much better. YRMV

Comfortable seats in all cars comes down to adjustability to fit all people, especially you as the driver. Not those 90 degree seat backs that are not good for anyone. Pay the extra cost, get the adjustable seat backs, form fitting base seats, good solid firm foam, and enjoy the comfortable ride.

There is a difference in foam and how long it lasts. I sat in my last 18 year old car with outstanding seats and pure comfort while driving. (60k miles) The driver's seat was comfortable, but not as comfortable as my passenger seat.

It was due to the constant in and out of daily driving, despite the leather seating surface and seats that were adjustable to the Nth degree. (and my wife being lightweight all of her life) Even the thigh supports were adjustable... but over time, and daily use, the good foam of original seats began to loose its stability. But, a 200 mile round trip to Long Beach was a common occurrence and it felt comfortable on every trip.

 

Upholstery supplies have seat foam and seat toppers also foam, from these you can can create a seat.

 

What I use on my bikes is just called High Density Foam. Its just tan and is the same stuff that they would use in your couch. Nothing majic at all. Just foam on a steel or aluminum plate for a base and covered.

 

I bought some 4" the other day at a local upholstery supplier. It's a firm foam. I'll use a softer foam for the back.

 

Don’t overlook stopping at upholstery shops that cater to the boating crowd. Seats are simple so the foam is the suspension and would be good for a rough riding rod. Most upholstery shops don’t mind helping out a do it yourself person.

 

A point on safety made to me by a friend in the upholstery business back in the '70s : MAKE SURE THE FOAM YOU USE IS FIRE RESISTANT RATED : There's nothing as sad as watching your ride going up in flames due to a dropped cigarette in the fold of the seat!!

 

The local guy who did the inside cushions for my boat had to order special foam for the boat. That stuff isn't cheap.
I don't smoke cigarettes and will never let anyone else smoke in my vehicles so that isn't a current issue for me.

 

Assuming you're near Oklahoma City I did a google search and found several auto upholstery shops in the area, one of them should be able to supply automotive grade seat foam.