Sewing hems on curtains without stitch showing?

Probably depends on the fabric and the look you want. You can use a blind hem stitch if you don't want the stitch to show from the front of the fabric, or you can use a simple straight stitch or possible use a twin needle (if you machine accommodates it).

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Good evening to you and your sewing machine.
If you have the manual there is probably a certain program for doing the hem this way in the machine.
If you are a little nervous of using the machine to do the hem you could do it by hand with what was called in my younger days " invisible stitch" or you can practice on a piece of cloth in the machine, take a look here Magic Invisible Closure and here
Hand Sewing Stitches How to Sew Hidden Stitch
If you do not have the manual handy you can always get it here Free User Manuals and Owners Guides ManualsOnline com

If you want it done entirely by machine you will need a special attachment. You'd have to check the make and model of your machine to find out if there is an attachment available from the maker. If not, there are some companies that make general attachments, and they'll list what machines these will fit. Check online sewing supply houses for this kind of thing.

You can also make one by hand. Any decent sewing book would tell you how. Usually you sew a straight stitch along the hem, using quite small stitches. Trim hem to a quarter inch from the stitch line. Crease the fabric or press it along the stitch line to the inside. Anchor your hand thread, then take a short stitch right along the stitch line. Next catch one thread of the fabric a quarter inch above the stitch line. It's just a basic running stitch, back and forth. Every few stitches, gently snug up the thread, which will roll the hem over. The finer the fabric, the smaller the stitches you take where they'll show should be.

There are some images that will help, if you enter the following search terms in google, you will see several pictures. Type the words," Illustrations for how to make a rolled hem by hand ? " and you will get a load of ideas.

Have you found the blind stitch foot? On my Elna SU it has a piece of metal shaped a bit like a boat rudder in the middle, going front to back. Do you know which stitch does blind stitch? On my Elna it does two or three straight stitches and then one zig zag stitch. Make absolutely certain the needle is in the centre position before you start, if not, it will get expensive on needles! Fold up your hem and press it, and tack it into position. Blind stitch is a bit different, you need to position the presser foot so that the hem is on the right hand side of the paddle, and the "body" of the item is to the left. In order to do this, you need to fold the body of the fabric again (but don't press it or it will leave a line). I'd suggest a few practice runs first on scraps of fabric, so that you get the fabric positioned correctly. It will also take a bit of fine tuning to get the needle to just take a tiny bit of the body of the item. I found it a great stitch for things like curtain hems, and fairly heavy fabrics like tweed, because done properly it's far stronger than hand sewing and the stitch hides itself in the fabric, but I find it difficult to get it just right.

here is a link to great info on sewing.about.com which explains this technique with images, http://sewing.about.com/od/techniques/ss/machineblindsti.htm

In brief, you need to fold the fabric to be hemmed into a Z shape with the wrong side hem edge at the bottom of the Z.

The Blind stitch is either three straight stitches then a wide zig zag which swings to the left and catches a little bit of the folded edge, or three small zig zags, then one wide zig zag to the left to catch one stitch into the folded edge. The zig zag style has a little more stretch in it so works good on jerseys and knits.
You need to use the blind hemming foot which helps you to line up the folded edge and keep it at a constant distance from the needle. It will look like this.
Turn the little silver screw to move the white plastic guide left or right until you've got just a smidgen of fabric being stitched by the left wide stitch. Always do a practice sample first to get the stitching and guide set right. On most machines you can vary the width of the big zig by adjusting the stitch width dial a little.

You need to adjust the blind hemming foot guide so that the needle is just catching a tiny amount of your folded fabric because this is the stitch which shows on the right side of the fabric when you unfold the Z. So forget trying to hem satin or expensive fabrics this way, a hand sewn stitch will give a much better finish.

Blind hemming works best on a hem which is continuously straight on the same grain line, its not great for a curved hem. So if you've got a tiered skirt or the frill on a bed valance, it is fine as the fabric edge to be hemmed will be a continuous straight length. You can use it on a slightly curved hem for jerseys as the fabric has more give, and patterns will help to disguise the stitching too.

I hope that this helps you to sew your blind hem, 4 thumbs up if so.

blind hem foot is good if you want to machine stitch a hem but not have a seam showing. it will have an adjustable piece you can move left or right with a screw. but blind hemming works best on straight grain and not on a curve like a skirt hem unless its a knit fabric that gives. to make a blind hem press the hem allowance up then turn the main garment piece back to form a Z shape. you then stitch along the hem side with your blind hem foot guidr running along the top fold and use the blind hem stitch which looks like three little zigzags then one big zig far to the left onto your folded piece taking a little 'bite' - this stitch shows on the right side when you press the top of the Z back flat. so you need to adjust the foot position and how wide the needle swings to minimise this stitch showing. hope this makes sense and helps you with your sewing.

bunching up on the bottom means that there is no upper tension...

you want to use a blind stitch. Refer to your manual and it should give you details on how to set the machine for that stitch.

You can find some instructions on a narrow double hem at http://www.sewjanetmoville.co.uk/content/learning/viewArticle.asp?lcArticleCategoryID=0&lcArticleID=3&pgid=learningCentre. Instead of machine sewing it, use a hand slip stitch as seen here: http://www.hutchal.clara.net/curtains/sewguide.htm.

You can find more info on these techniques at http://www.repair-home.com/how_to_sew_repairs.html

Hope this helps! Let me know if you need more info.

If you want to do blind hemming you need to find the stitch on your machine that looks like 3 small zigzags, then one bigger one, or 3 straight stitches, then one zig zag to the side. This is the blind hemming stitch. You'll possibly also have a blind hemming foot to use, which helps with guiding the fabric fold into the machine and keeping it even.

As the previous poster said, blind hemming is a little difficult to explain. You'd be best served by visiting http://sewing.about.com/od/techniques/ss/machineblindsti.htm for photos and intructions, getting a copy of a manual for your machine (if it doesn't have this stitch, then you're going to need to find another way) or getting a ibrary book out.

Blind hemming works best when hemming straight edges of fabric such as a ruffle on a full skirt - if there is any curve in the seam, it gets much harder and the result won't look so good. In essence, you press the fabric hem up, then fold the hem edge back under so you have a "S' shape, then sew along the single layer with the folded edge sitting against the foot guide. Then when the machine takes the 4th wide stitch, the needle swings to the left and catches a small stitch into the upper folded layer, then back onto the hem. The trick is adjusting the stitch so that the wide stitch doesn't show much on the right side of the garment.