The blade is most likely dull or nicked. Usually, one blade can be changed by the user. The other blade needs to be done by a technician because it requires some technical knowledge.

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Sounds like your blades are either dull, misaligned, disengaged or broken. Examine your serger book for how to re-engage the blades. If they are engaged, make sure they are aligned correctly. If that still doesn't help check for damage.

I take it this is a serger from the fact you have a looper. Try changing which looper thread is on top when you thread it. Mine jams if they're not done just right. BTW, the easiest way to thread a serger once you've got it once is to tie the new thread to the old and pull it through.

Hope this helps.

the serger probably needs to be checked at a sewing machine shop
to see if the machine is out of time & to make sure the loopers
aren't damaged

Can you wind the lower cutting blade to the right to cut less fabric and therefore fill out the stitching? On most sergers the lower blade position can be adjusted sometimes with a little knob or dial. You need to raise the top blade out of the way first, usually you put pressure onto it to release the spring holding it up against the lower blade, then swing it up to do this. Then wind the adjustment on the lower blade and move it to the right to cut less fabric then test serge. Your manual should give you more specific information on this and should be your first 'go to".

I would adjust my looper tensions to suit the fabric and width of the stitch I'm trying to achieve so yes, the settings you've been given are average tensions but its okay to vary these too. From left to right, I'd set 4, 4, 4, 4 and test serge again and see if this pulls the looper threads in against the fabric if moving the blade hasn't tightened up the stitching.

Sergers are more variable than a straight stitch sewing machine so its okay to move tension knobs a bit, just turn each a half number each time you adjust, then test serge and look at the stitch formation. Your needles tension should be fine at 4, leave them alone.

I'd suggest if you can find one, go to a "Getting to know your serger" type class as there is lots of techniques such as seaming on a curve, turning right angles, both inside and outside and making rolled hem edges that are very helpful serger skills to learn along with making adjustments and troubleshooting. Or go to you-tube and search some of these techniques for videos. Also www.sewing.about.com is a great sewing resource and Debbie has pages on sergers/overlockers here too.

When I'm starting a new dressmaking project I will spend 10 mins on the overlocker/serger, changing the thread colour to suit the garment, then test serging and adjusting the stitch tensions to suit the fabric. I have 4 cones of thread each in white, black, beige, grey, pink and pale blue and these threads will give a suitable finish on most fabric colours and prints. Then there is wooly overlocker thread, this is a fluffy thread that you can use for rolled hems as the thread relaxes once stitched and "fills" out the closely stitched edge covering the rolled fabric edge and is another whole area of fun to try out.

Often I'll just use a three thread to neaten the raw edges of a seam I will press open. Or I will assemble a whole knit garment using the four thread stitch, so much faster then stitching seams, then neatening. Jersey knits and sergers are made for each other.

As an aside the D on your machine model would denote "differential feed" too - briefly differential feed is adjusting the amount that the two feed dogs move under the foot and means you can "hold back" the fabric as it is stitched (0.5), or "stretch" it out (1.5 or 2 setting). Really handy for loose weave fabrics that stretch as you serge them, you can compensate using the differential feed setting. And in reverse, you can create a "lettuce" or wavy edge by turning the differential feed up.

I hope that this helps you out with your Brother 1034D and hasn't just confused you. Good luck.

Sergers are not really meant to sew very thick material. The blades have a maximum amount of range, or thickness that they can reach to cut. If you go outside that range, get ready for a big repair bill! You can break loopers and even the needle plate when you "push" a serger. My advise would be to use you sewing machine for the, "pounding" work. The type of material matters too, A thick Quilt like fabric can be sewn becatuse it's not dense material. A thinner harder denim could max out at 3 layers because of it"s hard finish. If the fabric you're sewing isn't dense like, you could just need new knives.

This problem is usually when the lower blade drops below the sewing plate. Look at the blade in relation to the plate and see if it has dropped below the plate, then you can reset the blade. If it is not the upper blade may be too dull to cut so it will need to be replaced.

For now, it works only satisfactorily:
I applied alcohol to further clean both blades,
dried and then oiled them. There seemed to be a slight gap between blades;
the fabric was dragged into the gap instead of being cut.