I need help to adjust the setting for knit fabrics on my friend's white Jeans Machine sewing machine...We've lost the manual. Thanks for your help!

What you are getting is what's called lettuce edging.
How to Sew Lettuce Hem Two Ways

You could unconsciously be holding the fabric back when it is feeding through the machine so you are building in stretch. Or, the presser foot pressure could so high that the presser foot is actually pushing the fabric in front so it is building in stretch. If you have a presser foot pressure adjustment on your machine, you might try loosening it some. It would be helpful to use a roller foot or walking foot (if you have one) that will not impede the movement of the fabric but instead help the fabric move through evenly. Also, lengthen the stitch length and add a zig-zag. That will give the garment some give, but if the fabric does stretch, it will also go back to flat once you remove it from the machine.

How to Sew Knits and Stretch Fabrics with Sewing Machine
Sewing Stretch Fabrics
Sewing with Stretch Knit Fabric Part 2

Your machine takes standard sewing machine needles, available from quite a few manufacturers like Organ, Schmetz and Singer. I have even seen them for sale in drugstores! Most people use #11, #12, or #14 needles--the higher the number, the larger the needle, and the thicker the material. In addition, Sharps are used for all woven fabrics like cotton and wool; ball point needles are used for things like t-shirts and other knit fabrics. Home sewing machine needles range from #8 to about #18. For instance, you would probably use a #14 or #16 needle for Jeans, although for those, there are also specialty Jeans needles you can also use.

I'm a bit confused, this isn't a serger machine as far as I can see. So do you mean an overcasting foot where you sew a XXXXX type stitch along the edge of the fabric? The overcasting foot just helps you to line up the fabric edge and sew over it neatly.

if you go to this page http://www.sewingpartsonline.com/necchi-6022-sewing-machine-parts.aspx
there is an instruction manual for sale.

http://sewmamasew.com/blog2/2009/06/feet-feet-feet/ is also a great resouce on sewing machine feet with good photos of what they are used for.

Here is a video of overcasting foot in action http://www.sewingmachine-sales.co.uk/sewing_machine_info/video/34/adjustable-overcast-foot.html

If you are wanting to sew knit fabric then you just need to use a small zig zag stitch and a ball point needle to put elasticity into the seam. Or your model may have a stretch stitch, where the fabric is moved forwards and backwards during the stitch formation to add some elasticity.

Sewing elastic stretched onto fabric is a bit different with a SM, can be fiddly and hard to keep everything lined up nicely and stretched. Some machines have a little device which clips onto the needle plate in front of the needle that you can feed elastic through and tighten it to tension it, then just use a three step zig zag stitch to seam over this onto your fabric. But I don't know if Necchi has such a thing, your needle plate would need holes in front for it to clip into. Elna had these on their swiss machines in the 80's but haven't seen a similar device for a while.

Hope I've answered your question and not completely misunderstood your problem. Purchasing a manual is often the best way forward when a machine is unfamilar. Or www.sewing.about.com is great resource.

Most machines can sew on jeans fabric, but you may need to go slowly or even hand-turn the needle when crossing thick seams to keep from bending or breaking your needle.

Bobbin: It won't matter if you use plastic or metal bobbins.

Needle: You should use a heavier needle - you can purchase 'jeans' needles, or use the heaviest sharp or universal needle you have.

Tension: For tension adjustment, you can follow the guidelines in your sewing machine manual but you'll also need to adjust the tension based on sewing on scraps of the fabric. If you are sewing light-weight denim, the settings are pretty much the default/normal settings. As you increase the weight/thickness of the fabric and seams to cross, you'll need to loosen your pressure foot tension. If you use decorative 'jeans' thread or topstitching thread, you'll need to loosen your needle tension.
*Always test on scrap fabric to make sure the stitches are forming properly. It is best to make small adjustments to your tension settings, then test, then adjust and test, until it is right. If you sew that weight of fabric often, make note of your tension settings inside your machine manual to save you some time the next time you sew.
I hope this helps.

Hi. You use different size needles for different fabrics and fabric weights. Size 16 needles are used for heavy fabric, like canvas, duck, or blue jeans. Size 14 needles are still on the heavy/thick fabric size. Size 10 needles are for very light-weight fabrics and size 12 needles are for medium-weight fabrics. Also, you need to pay attention to the type of fabric--if sewing on knits, you need ballpoint needles. If sewing on woven fabrics, you need sharps or universals. Universals are supposed to be for knits, too....but ballpoint needles are SO much better!
Use the right size and type of needle for your fabric, don't sew over any pins (they can bend or even break the needle), and make sure you don't pull or push the fabric while you're sewing on it. Let the feed dogs do the work of moving the fabric--you just gently guide it.
Hope this helps!

This is a very highly regarded serger. Check out the reviews on http://sewing.patternreview.com if you're interested--but they are all extremely positive.

I also checked out the White Sewing Machine site--the three sergers they currently sell all use regular sewing machine needles.

Based on what I read on both sites, I believe your machine also uses regular sewing machine needles (not all sergers do, BTW). To be absolutely certain, you can call the White Help Line (l 800-331-3164, Monday through Friday 8AM to 5PM, EST).

If your serger uses regular sewing machine needles, then the size of the needle depends on the type of fabric you're sewing. Sizes 8 to 10 for lightweight fabrics, 12 to 14 for medium weight fabrics, and 16 to 18 for heavy weight. Use ballpoint needles for knits, jeans needles for denim, and universal needles or sharps for woven fabrics.

15x1 or 705 or Organ make of needles

Hi, getting a lettuce edging on knit is not in the settings . To get this effect, you need to stretch the fabric as you feed it thru the machine. Try it on a scrap first to get the right effect, then try it for real,

You can find it here:
http://ifixmachines.com/index.php?page=shop.product_details&product_id=3289&option=com_virtuemart&Itemid=54

Try this link:

http://sewusa.com/Sewing_Machine_Instruction_Manuals.htm