WARPED/TWISTED CUSHIONS! =( help me

[Regina NEEDS help]

Ok So I am a total newbie.

This is my first project.  I am making cushions for an outdoor semi circle fire pit bench seat.  Its 4 long cushions, 4 ft each cushion.  So each one of my cushions keep coming out slighting warped/twisted.  Not sure what I am doing wrong or how to prevent this from happening.
Here are the steps in which i used to make this project: (maybe I am missing math somewhere I dont know! I will post pictures of my problem)
- I created a pattern from butcher paper.
- Added 1/2" all around the pattern for seam allowance onto sumbrella fabric
-made my own piping.
- The foam itself is 2" thick.  My seam allowance that i am useing is 1/2". I read to only add 1/2" instead of a whole inch to the boxing (total of 2 1/2") bc it will make for a better fuller cushion. not sure if this is part of the problem. I cut the length of the boxing to match my top and bottom plates so 1/2" was included already on both sides for seam allowance.
- cut out the fabric plates and boxing. 
-*I read to increase the zipper plaque length by 1.0125 % to account for shrinkage.  however in the end I found that this was too much material, I woudl end up cutting off a bit. not even sure of this is needed, but hoping a pro could help me out with the math of the zipper plaque. 
- Sewn it all together
-used my original butcher paper pattern to trace on the foam.  From watching sailrite videos, they said to add 1% to both dimenstions of the foam and to never add less than 1/2".  So I added 1/2" to both dimentions W/L. 
-Cut the foam, stuffed it in, which was not fun at all. was a very tight fit, which was nice.

I figured after the first two cushions coming out warped that maybe the problem was with the foam, maybe i added too much to the length and width and that was causing the weird twist of the cushion.
So the third cushion I only added 1/2" to the width instead of the length.  And low and behold of course the cushion was twisted again! I dont Know what I can do to correct this problem.  Any help/tips would be greatly appreciated. 

I knew doing a semi circle cushion would be challenging as a first project, and there is a lot of math to this, so Im hoping either my math is off or maybe there are ways to avoid this.  I also made one rectangular box cushion with no problems of twisting.

=( I need help here!

[Regina NEEDS help]

Here is a link to the pictures.

Any help is greatly appreciated.

Let me know if the link doesnt work.

https://www.flickr.com/gp/139730956@N05/658w15

Thank you guys!

[SteveA]

What type of thread does sunbrella suggest for their fabrics ?
SA

[cajunpedaler]

I think the foam is not heavy, dense or stout enough to hold the cushions out to the shape.  And because they are so long, the fabric is going to overpower the foam.  I think if you could cut wood bases for the cushions, and then cover the foam that is glued to the board, then cover with fabric with staples, I think you might get a better result.
Your sewing looks adequate, it appears that the foam is a lightweight and the fabric is a heavyweight...
I always put foam in a "pre-cover" muslin or cotton liner, with polyester batting glued to foam to give it desired loft. 
Perry
Experience is the best teacher.

[Darren Henry]

-made my own piping.

Couple of questions;
>What size welt cord and welt foot are you using?
>what order did you sew in? Some people try to make the welt as they sew it and the panels and the border all in one pass. I've never had much luck with that. when I first started I sewed up my welt then sewed it to the plates and then sewed on my border & zipper plague. I often fought with exposed stitches from the second pass in the corners. I usually make my welt and then sew the three components together in a second pass.

One of the first cash paying projects I did was V berth cushions for a 27' sail boat in a light cotton denim. The only machine I had at home at the time was my old 31K19 singer with the rolling foot that I used for making shoes. Without the walking foot I was having so much trouble with keeping them aligned that the old lady and the dog went and hid under the water bed. They were doing exactly as yours.

When you adjusted your 111 for those thick seam issues did you back off the presser foot tension? A simple test to see if your machine is walking the fabric on you is to cut two long  (6-8 foot) strips of scrap fabric the exact same length and run them though the machine. Don't try to "sew" them, just feed 'em in and let 'er rip. If your machine is set right they will be same length when you get to the other end.

I would suggest you turn one inside out and rip out one of the plates. The other plate and border should sit there like a giant cake pan. If it does make a truckload of reference marks on both plates and the corresponding point on your border. Staple the heck out of the plate you are about to sew back on lining up the reference marks on it and the border. It should look like a nice square inside out cushion. If it does; sew it up and go "Dang that homely old goober was right again". If not, white out this  paragraph please.

[brmax]

ya had me until the end Darren now roflol
Floyd

white out

[brmax]

Darren thanks, as always right as rain.
I had machine off about an 1/8th on a 4' run did it 5 times.
kept backing off pressure total 1-1/2 turns right on the mark, so put needle back in tested material lays flat as good ski water.

have a good eve
Floyd

[gene]

I started to get up to get my bottle of white out and read Floyd's reply and realized that it was a joke.  :)

This is my first project.

Newbies always seem to start with a very difficult cushion. And your cushion is in the difficult category.
As a newbie you are not yet grateful that you are working with sunbrella fabric on this project instead of some loose woven $3.00 per yard fabric that stretches more than an octomom's stomach.

My 2 cents, which by the way, if adjusted for inflation from the year I was born is now worth 17 cents:

I think the problem is that the foam is too big.

When I cut out the fabric panels, I use a panel to trace onto the foam and this is the size of my foam. The panel is 1/2" bigger all around for the seam allowance, so the foam is now 1/2" bigger all around than the finished cushion cover. This makes for a snug fit.

I cut the boxing 1" bigger than the thickness of the foam. For a 2" foam, I cut the boxing at 3". This gives me a 1/2" seam allowance on the boxing and the finished boxing is 2". I always use poly batting on my foam. For outdoor cushions I use an outdoor poly batting. This poly batting makes the foam fit snug across the 2" dimension.

Practice makes perfect, except when it comes to boxed cushion covers. It only makes you a bit better for the next time.

There is no one way to make a boxed cushion cover. There is, however, a perfect way to make a boxed cushion cover. And you will only know if you used the perfect way once you have finished and the boxed cushion looks awesome!

Best regards,

gene

[Regina NEEDS help]

Thank you all for your input!
You guys are great!

Going to try out what Darren said about testing my machine with the 6' fabric to see if it matches up in the end. And also going to use a stapler to keep material in place as well as a bunch of reference marks. Since I have made 4 cushions (and all came out twisted) I will try to take one apart and see if i can realign it with the reference marks and stapler. These cushions by the way are for personal use and not for profit, however I need to get my Sh*t together because I am learning all of this in order to make a profit eventually. 

eek! ok off to the sewing machine I go. 

[Regina NEEDS help]

"When you adjusted your 111 for those thick seam issues did you back off the presser foot tension? A simple test to see if your machine is walking the fabric on you is to cut two long  (6-8 foot) strips of scrap fabric the exact same length and run them though the machine. Don't try to "sew" them, just feed 'em in and let 'er rip. If your machine is set right they will be same length when you get to the other end."

So I did what you said  Darren and this is what i got! is this normal? what do i have to do to correct this?

https://flic.kr/p/DBNh9R

[brmax]

Regina, as another tradesman at the bench. I will say what worked for me as to what Darren mentioned because some issues I was noticing on mine, and ongoing they always are. Thanks to the group here, anyway On my test yesterday like your photo on top: back off some pressure and on the lower test strip in photo add pressure by clockwise turning on mine to add. again this worked on mine
I'm going to add from my view stitch looks good "this side" so keeping an eye here with both yours and my setting changes probably wise.
With Genes description I am seriously looking at also, now the fix? I will wait, sorta.
Yesterday I wondered what if any covering you could use to say help load the foam in the cover. Because I thought something may help there. I know many use materials and are able to remove them afterwards, obviously have to on outdoor cushions.
I want to mention Gregg had about the best manual on 111 I seen and also others mentioned to, for some reason I cannot open it or its history on my pdf list but worth looking at his site for a download.
great work
Floyd

[kodydog]

All great advise by the folks above. I think Darren's advice about the reference marks will solve your problem. Another thought to add would be to pin the whole thing together at each reference mark and take a good look at it while its laying flat before you start sewing. Also where the back of your cushion is curved is called cut on the bias. This makes the that part of the top panel very stretchy. And because your boxing is cut on the straight and not stretchy, it is very easy to get all catywhompus.

If you sew the boxing to the zipper first, before you start sewing, it is doubtful everything will end up in the right place when finished. I cut the boxing 6" longer than necessary. I don't sew the zipper to the boxing till later. I usually sew the zipper onto the panel first. Sew it all the way across the back of the cushion except the last 5" on both sides. Leave it just hang off. Then sew your boxing. When you get to your zipper you will have more boxing than you need. At this point lay the boxing over the zipper and allowing for a 1/2 inch seam measure and mark where the seam should be. Then cut the boxing down to the correct size and sew the boxing and zipper together.

[Darren Henry]

Good point about the bias Kody. After this many years you don't think about the physics anymore you just know it's going to happen and use a few more staples/reference marks. [BTW the pliers style staplers like your dry cleaner uses to put your tags on are bee's knees. They are available for standard office staples. I bought my last pair at Wilson's business supply because the first pair I bought was in an obscure "calibre" that the dry cleaners use and ordering staples was a PITA]

I too cut my boxing long, but I sew it to the zipper. I line the zipper up with the back of the plate and start sewing 6-8" from the free end of the zipper watching to ensure the zipper plague stays lined up with the edge of the panel as I sew. This places the seam at the corner when you turn and head up the side.

I wondered what if any covering you could use to say help load the foam in the cover.

I almost always spray my cushion cores with silicone before I stuff them. In the last couple of years I've become a huge fan of plastic wrap as well. It's not just for leftovers any more LOL. I just put it on the corners of arms and backs when I'm fitting one of those "pre-sewn assemblies" that the industry has adopted and the leading corners of cushion cores when I stuff them. Note ---get your own roll or have it back in the kitchen before supper dishes are done. It can get ugly---apparently.

Another little hack is to extend your zipper up the sides of the cushion 3-4 inches if you can. This lets you roll it onto the foam instead of stuffing the foam into an opening 1" narrower than the foam. This lets you manipulate your salvage and centre the boxing as it goes on instead of having to reach in and fuss with it later. N.B; I wouldn't worry about that on this project---we'll get 'em sorted out by re-sewing the one plate I'm sure.

is this normal? what do i have to do to correct this?

No, they should still be the same length. Your feed dog has teeth like a saw/ your presser foot is smooth and with a welt foot has a smaller contact surface than the feed dog. As Floyd said by increasing or decreasing the pressure on the presser foot you can control the amount of "slippage"  on each side until they are equal. This is adjusted on that shaft and knob that come out of the top of the machine between the take up lever and the tension discs.

These cushions by the way are for personal use and not for profit, however I need to get my Sh*t together because I am learning all of this in order to make a profit eventually

Cut yourself some slack Reggie. I got starved out of custom making orthopedic footwear 21 years ago and took this up. I screwed yesterday and had to do a "do over" on a simple furniture repair job today. BTW if you think I know a bit about machines----you should see my tutorials on seam rippers!!!

[Regina NEEDS help]

I just wanted to say thank you all again.  This site has really helped me out in so many ways. I feel like you all are my go-to for advise and help and I appreciate all the encouragement and ides. 

I have no clue how to adjust the pressure foot, but tonight I plan on tackling that job.  Trying to mentally prepare myself for my next big project of reupholstering boat seats! Wish me luck!

Im sure you'll see me on here soon enough! =P

[gene]

What type of thread does sunbrella suggest for their fabrics ?
SA

I think sunbrella sews like any other fabric.

Here's a pdf file from sailrite.com.

gene

http://www.sailrite.com/PDF/Thread%20and%20Needle%20Recommendations.pdf