Making a rounded corner on a cushion?

[nigelmercier]

I made a seat cushion last year, but thought I could get away without rounding the outside corner, it doesn't look good.

The cover is made from a + shape of vinyl, with the sides folded down, so no seam on the top edges.

I can't get my head around if it is possible to round the corner!

 

[doug748]

If I have understood correctly, I don't think you can. If you could run a line of stitches along the folded seam it would pull it tight and could look much better, might be impossible to get in there though.

I am no machinist but I have made cushions with rounded edges by cutting out the top and bottom to the shape required (plus seam allowance) and stitching to this a band of material that equates to the thickness of the foam (again plus seam allowance * 2). Working inside out.

How are you getting on with your Sailrite machine BTW? I keep looking at it but dare not spend the money.

 

[Hydrozoan]

Mrs H (who BTW thanks again for the HH course recommendation - she's nearly finished the saloon) goes along with Doug - again assuming we have understood your + description correctly. She, too, says you really need a separate panel for the cushion edge.

I ventured (cautiously) that that was an "I wouldn't start from here" sort of answer, and that you might want to avoid a top seam to match other cushions. I then suggested starting with a + with one corner not removed and folding it down with a couple of darts on the vertical edge, on each side of the corner. She wasn't impressed, and said that you'd probably need a series of such darts, and the result probably wouldn't look very good. I suspect that Doug and Mrs H are right, but perhaps an upholstery expert will be along in a minute – or you might give HH a ring to see if they have any ideas?

 

[LadyInBed]

If you have not got a face edge, then you will have to use pleat's, it could be as many as six on each corner, depending on the radius. Not easy on vinyl.
A corner template made of three ply or hardboard would help.

 

[William_H]

If I have understood correctly, I don't think you can. If you could run a line of stitches along the folded seam it would pull it tight and could look much better, might be impossible to get in there though.

I am no machinist but I have made cushions with rounded edges by cutting out the top and bottom to the shape required (plus seam allowance) and stitching to this a band of material that equates to the thickness of the foam (again plus seam allowance * 2). Working inside out.

How are you getting on with your Sailrite machine BTW? I keep looking at it but dare not spend the money.

+1 for seams top and bottom. good luck olewill

 

[charles_reed]

Putting in darts to modify the current corner is a simple, but probably unsatisfactory course of action. The other way, of making a saparate front panel would probably work, in a textile upholstery material but I'd br unsure of yout chances of success in your current fabric.
I'd leave well alone, having spent a day at a sewing machine on furnishing fabrics yesterday.

 

[seanfoster]

I'm no seamstress (well that would be physically impossible), but have turned my hand to upholstery on a number of occasions and have often encountered rounded corners.
Youtube is your friend to find tutorials on learning the basics, but from your description, you are right in assuming it isn't possible without a separate top and bottom panel.
However, rounded corners are relatively easy to do and results are (usually)very satisfying.