The Upholstery Forum

I’ve searched and tried to see in the videos in the courses how to pattern an insert but adding a standard seam allowance to the outside of the shape doesn’t work in this example.

This is a test practice piece. It’s a simple diamond pattern insert into a three sided panel, as it would be in a seat back.

I realize that when I sew foam and stitch the diamond pattern the insert is smaller. Yet presuming I just take that out of the picture if the outside piece has a window the same size as the insert plus a half inch seam allowance (1/2” inside…so if stacked face up there’s an inch overlap) yet when used it together the outside piece appears too long across the top.

If the outside piece was three parts two sides and a top I can make it work but apply those same measurements to a one piece outer.

If my finished pattern is 10”x7” I add half an inch seam allowance around it so 10.5x7.5. What size should the hole be in the outside piece to fit seam to seam to fit the pattern. 9.5x5 should give me a half inch to sew to the insert but it’s wrong and I’m not sure why. Any help is appreciated.

I would make the outside part out of three separate pieces myself. Sew the top brown piece to you diamond insert, then add the side pieces. With you brown outside piece being one solid piece it will be more difficult to sew in you insert with the 90 degree corners and make it look good. If you have to for some reason keep the outside part one piece I would radius the corners to make it easier to sew up.

Appreciate it and it simplifies greatly if I do that but still hoping for some explanation on how to better approach it in case that's not an option. These are just practice and for some reason I can't get my head around the backwards sewing part when the pieces come together and the videos just aren't showing me what I'm missing. I start in the right place but by the time I get past the first turn it doesn't connect by a long shot on the other side.

I'm building a custom seat from the frame up and have it patterned. I'll likely have to do it twice first in vinyl to work out the kinks and as practice, then in leather if that doesn't go to badly.

I may try the three piece and use that to practice a hidden stitch on the connecting parts on the brown parts. Then I can decide if it looks good.

Thanks again.

Shouldn’t your insert piece be 11x8? 1/2 inch on all sides. And then your outside piece would need to be 9x6 on the inside.
I am new at this, so I may be totally wrong and hopefully corrected.

I think @Jim is on to something. If you add 1/5 in on each side then the finished measurement will be a ful inch. not a half inch. That is one of the reason that a 1/22 seam allowance makes it easy to lay out. need 10x10. cut it one inch bigger... 11x11.

Also I think you are going to have to makes some snips in the corners when sewing and be careful to stop short of the end of the material when you make the turns. I am sure I would end up upside down and backward by the time i got to the end.

Show pic of your finished project.

sorry for the typos... it is eary and i havent had my coffee yet.....

@vicstric , better make a big pot. I have keep up the great work!

Jim wrote: ↑Tue Aug 03, 2021 10:40 am Shouldn’t your insert piece be 11x8? 1/2 inch on all sides. And then your outside piece would need to be 9x6 on the inside.
I am new at this, so I may be totally wrong and hopefully corrected.

Here's a better representation of the problem, maybe this will help. I'm adding a 1/2 on each side for a total of 1" on both sides. Basic 1/2" seam allowance

Check out this video. It may help you out.

I've watched Chechaflo's videos and they are great. I'll watch again. John's course videos too. I can easily solve it by making the border panel 3 parts. What I'm trying to understand is why in this one case when I pattern, adding the same seam allowance doesn't work in the type of config I'm showing. I don't think I would actually use it on a seat back, but can see it in a door panel. I can fake it by reducing my pattern insert in the long dimension.

It wouldn't matter except I'm patterning my own seat and this makes me feel like all of the explained detail on allowances doesn't work in this case, so want to understand why.

I'm probably over thinking it and will finish out my practice pieces in 3 sections like above. Thanks for everyone's help.

If the colours on your pictures are an accurate representation of how you are sewing the panels together, once you fold the 11” insert over, you will have 10” left. But the cutout of the frame is still 9”. That would put 1” of the insert over on the other side. Does that seem to be what’s happening? If so, then I would tend to think it’s the way you are starting the seam. Flat versus pinching it together to form a T.

so the cutout should have an opening 9 inches wide and the insert should be 11 inches wide. If these are your measurements it should work. Have you actually sewn this up yet or just visualizing it? As mentioned a pattern like this will be tricky on the corners.

Is your material stretching and flattens as you sew?
When you lay the pieces together before sewing to check fit, does it match up?
Since you are patterned for 90 degree corners you could mark centerline on insert and centerline on other piece and sew the middle section first then sew the two outside seams.

@vicstric is correct. "the cutout should have an opening 9 inches wide and the insert should be 11 inches wide"
If thats what your measurements are then something wrong is happening when you sew it.

Let us know if that fixes it. Were here to help!