I can't find my Bernina Serger 800 dl manual - how do I thread for a 2 thread rolled hem, and do I need a upper looper cover and that the heck is that anyway?? Thanks

Most likely. Most overlockers can make a rolled hem. You will probably want to do a lot of practicing on scrap chiffon before trying it on the real thing. It involves using only one needle, both loopers, and making appropriate adjustments to the machine.

Serger 101 Threading the Juki MO 654de Machine for Roll Hemming by CKC...

How to Serge Rolled Hem

Serger Stitches 101 Cheat Sheet Never Ever Without It Your New Must Have...

Bernina has some very nice Serger Workbooks that could be helpful:
Bernina Mastery Workbooks

I don't know your model in particular but generally this is how you set up a serger/overlocker to create a rolled hem. Remove the left hand needle and thread if 4 threads are threaded). Now there is usually a lever around the stitching area that you slide back towards you to remove the stitching finger back (disengaged). Then you adjust the top looper tension looser (about 2-3) and lower looper tension tighter (7 or 8). Leave needle tension at normal tension (5). You may need to move the cutting blade to the right too. The technique is to cut the fabric wider but with a narrow stitch so the cut edge rolls under within the stitching. You want the top looper thread really loose so it rolls right around underneath up against the needle thread, the lower looper thread needs to be tight and almost invisible, pulling the upper looper thread down. I usually do a few test runs and check the stitching. Once happy, I turn the stitch length right down to 1 so it is very dense. This uses a lot of thread up.

Ideally use a wooly overlock thread on the upper looper as this "fluffs" out once stitched and "fills" in covering the fabric edge completely.
some good images here
Sewing Basics Narrow Rolled Hems with Serger Sew Mama Sew Outstanding...

Your owner's manual should have instructions for rolled hem settings. My Bernina manual has a the following settings:
Medium weight fabric
80/12 Universal needle
3 cones serger thread
Upper looper 3-5
Lower looper 7-9
Left needle (no thread)
Right needle 3-5
Stitch length 1-1.5
Cutting width 2-3
Differential feed N

Can use woolly thread in the upper looper, but the tension may need to be loosened since the woolly nylon thread will stretch.


Make It Handmade Threading Your Serger or Overlocker

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Depends on your serger model. Best idea is consult the owner's manual. Some manuals are available for download on Bernina's web site (look under Support). Be sure to thread in the order specified in the manual. Usually the upper looper is first, then the lower looper second, then the needles. (Hint: The lower looper thread ALWAYS lays over the top of the upper looper thread in the final looper threading step.)

You can also download a serger workbook too.

BERNINA of America Premium Swiss quality sewing machines BERNINA

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Sounds like you want to do a rolled hem for a handkerchief edge, I do the following to create a rolled hem on my over locker. Take out left needle and cut and remove that thread. Open front cover and slide back lever for the stitch finger in the needle plate, this finger stops the fabric rolling under thread tension normally so you need to pull it back out of engagement. Your Janome may have a similar means to select the rolled hem or you may need to remove the stitch finger with a screwdriver, it varies between models.

Thread upper looper with wooly nylon and right needle and lower looper in matching colour thread. (You can go wooly on the bottom looper but it hardly shows so I never bother.) Disengage upper blade and move the fixed lower blade to the right to trim less, then lower upper blade back into position. Now tension, needle leave alone (5)' upper looper very loose (2-3) and lower looper tighten up to 6-7 and test stitch. You want the upper looper thread to go right underneath and the lower looper thread to disappear against the needle stitch. And the fabric to roll inside the stitching. Finesse tensions on the loopers until this is right, you may need to change blade position too, depends on weight of the fabric and how it rolls. Once this is right turn stitch length down to close up stitching, 0.8 or even 0.5 if you want full coverage. Thats it. You can use differential feed if you want a fluted rolled edge, nice on knits.

I don't know your babylock well, some of these have automatic tensions and electronic stitch selection. But a rolled hem is achieved on any overlocker in the following way; the actual dials and knobs might vary a bit.

Firstly there is a stitch finger that you need to change or retract so that the thread can roll the fabric rather than staying flat. For a normal seam this finger sticks out in the area where the loopers and needle form the stitch holding the cut edge flat until the seam is made over it. But for rolled hems you want to retract this finger so it does roll.

On the Bernettes this is a little lever in front of the stitching area that you pull back to retract the finger. Have a look around where the stitch forms and you should see the finger. Some machines, its a part you change on the needle plate with a screw driver, or just move a switch or lever.

You want the right hand needle in place, remove the left hand needle.

Thread upper looper with wooly overlock thread, this is a fluffy nylon that pulls flat under tension but relaxes and "fills" out once its stitched into place. Gives that lovely covered look you see on shop bought tablecloth edges. Your regular thread in needle and lower looper. Usually cutting blade to the right side as you want it to cut more fabric than in the seam so it rolls under. Now loosen off the tension on the top looper, (I use 2 on mine but this is something you need to finesse with each machine), and tighten up the tension on lower looper, (about 7). Leave needle tension alone.

Now test stitch on your fabric, and finess the upper and lower looper tensions until you get the lower looper thread almost not showing, it should be right up against the needle on the underside with the upper looper thread completely wrapping around top and bottom, pulling the fabric under.a seam like this.


Test stitch and adjust upper and lower looper until this is happening.

Now, turn stitch length down to close up the stitching, probably 1 or 0.8 if you want a real satin stitch look to the hem.

Because of the stitch density this uses thread so do the finessing first, then turn the length down.

That's it! Now right down the tension settings you used and keep handy for next time.

HI
I would reccommend regular serger thread for the right needle (left needle is removed) and the lower looper. and use wooly nylon in the upper looper
The tensions on the needle should remain at 5-6 upper looper thread tension should be about 3-4
and the lower looper tension at about 8
contact me at [email protected] if you have further quetions
Wayne Buss

You might take a look on ebay item 150416413591

Here is a little jingle to remember as far as the order of threads to thread...
Upper looper, lower looper, left needle, right.
Usuall if you give numbers to the threads from left to right as 1,2,3,4 , you would thread it in the order of 3, 4, 2, 1 . Also when threading the loopers be sure the lower looper thread goes over the top of the upper looper thread as it goes out the back.
Hope this helps.

You need to disengage the cutting blade by openingfirstly opening the front and left hand side covers. pull on the larger of the two silver knobs and slide the red lever towards you. I'm not sure what the tension settings are, but I'm certain you need to reduce them a fair bit to aid in the rolling effect. I only use 3 threads when doing a rolled hem.
My description isn't too detailed but I hope it helps!