Sew Foam

[bobbin]

The many curved and shaped yacht seats shared here lead to the following questions:

1.)  Some of you glue the foam, some sew it.  When do you do which and how do you arrive at your decision?
2.)  Do you ever apply sew foam to add some loft to an existing foam base?
3.)  Do you glue the foam side or the tricot side (guessing the foam side)?
4.)  How do you decide if you'll used 1/4 or 1/2"? which size is your favorite, "go to" size?

[jojo]

Hi Bobbin,
If I can get away with not using it, I will. But sometimes you need it to hide pits or small gouges in the foam.
I always glue it; I've tried just sewing it, but sometimes by the time you get all the way around the edges of a large piece there's a little bubble, no matter how hard I've tried to prevent it.
And you are correct - you glue the foam side. The tricot will then glide smoothly over the machine bed while sewing.
On Marine, I always use 1/4", unless you are making your own pleats, then use 1/2". For cars, use 1/2".

[JuneC]

And I never glue.  If the pieces are straightforward - like a rectangular cushion, I don't bother, but on almost everything else, I sew the foam to the fabirc, scrim away from the fabric unless it's an inside curve - then scrim goes next to the fabric.  On the other pics I posted, the seat back had the scrim next to the fabric but the seat bottoms had the scrim away from the fabric. 

And I use 1/4" on just about everything I do.  I go through scads of the stuff.  1/2" is too thick unless doing tuck-n-roll, especially if there's welt involved.  Imagine trying to find 5/32 welt through 1 inch of foam!  Also, the thicker the foam the more difficult it is to hide the selvedge.  That 1/2" of foam selvedge pushes out below the seam and goes seriously ugly.   

I usually staple the bits together before assembly unless it's oddly shaped.  Then I sew the bits together beforehand.  Makes life really easy and avoids the problem that JoJo identified.  You have to attach it somehow before assembly.  But.... it's time consuming.



June

[bobbin]

Thank you both for the good information!  I suppose working with sew foam is like anything else we do, you develop your own little techniques out of necessity. 

[Mojo]

I always glued and then sewed. It helped me keep the fabric and the sew foam together.

I bought a large roll of sew foam several years ago and then had to go back and buy more a year or so ago for a project. I am not crazy about the newer sew foam. June knows what I am talking about I think.

The sew foam from a few years ago had a grey fabric backing and was really good to work with. This new stuff I personally do not feel is as good. Maybe its just me.

Thankfully I have very little call for doing vinyl anymore and pawn off that work to others. :)

Chris

[baileyuph]

The auto interiors have gravitated to what appears foam bonded to the upholstery fabric.  It sure works out in terms of bulk issues and lack of bonding potential issues.

One thing observed by using sew foam is it can get in the way of taking advantage of upholstery fabric stretch.  This explains why auto interiors are handled the way they do by them.

Several factors to digest, a bit more than just sewing sew foam to the upholstery fabric, vinyl or a woven fabric. 

Quarter inch is the most popular, half inch, for me, comes in for restoring older seats some times. 

The over riding issues are bulk in the seams, particularly at corners and inside curves and stretch compatibility of the sew foam and finish material.

The technologies of how foam backing on fabrics are handled have changed considerably the last several years.

Doyle