Fabric not feeding on simplicity serge pro. Seems like the feed dogs are not high enough. I've changed the differential speed settings and the foot tension setting.

According to the manual, your machine does not have the capability to drop/raise the feed dogs. Instead, there is a cover plate that is installed over the feed dogs when performing darning or free motion quilting.

Check that your stitch length is set high enough to actually move the fabric. Some machines also have a presser foot pressure adjustment that will increase or decrease the amount of pressure the presser foot applies to the fabric and the feed dogs. If your machine has this adjustment, it may help to increase the pressure so the fabric will move better. Another thing to check is whether you are using the correct presser foot that will actually rest on the feed dogs.

Reading the hints on pages 28 and 29 may be helpful.

User Guide Manuals LS 2020 Others Brother

Another possibility is that the feed dog points have been worn off. When the points are worn, they no longer grip the fabric like when new. When stitching, be sure to never run the machine with the presser foot setting directly on the feed dogs, it without fabric.

Make sure the stitch length is set high enough to actually advance the fabric--the feed dogs actually need to move forward and backward.. The stitch length control controls how much the feed dogs move the fabric. Also, check if your machine has a presser foot pressure control. This manages the amount of pressure the presser foot applies to the fabric, causing the feed dogs to grip the fabric in their movement.

If these do not resolve the issue, you may need to take it for service.

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Check that the Stitch Length is set high enough to actually advance the fabric, ie #2. Also, have the feed dogs been dropped, ie for darning? Be sure the feed dogs and bobbin area are cleaned of any lint, thread pieces, and gunk. If it is an older machine, perhaps the feed dog tips are worn. Is there enough pressure from the presser foot to actually force the fabric to react to the feed dog movement? Otherwise, the machine may require service.

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Lower the front feed dog

Make sure the stitch length is set long enough to actually advance the fabric. If set too short, the fabric movement will be very minimal. Also check that the presser foot pressure adjustment is set for the type of fabric you are sewing. The adjustment can be made for light- or heavy-weight fabric. If the presser foot pressure is too tight or too loose, it will have difficulty pulling the fabric.

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Check to be sure you have not inadvertently dropped the feed dogs on your machine. Dropped feed dogs are used for 'darning' or 'free motion quilting.' Below is info from Troubleshooting Manual:

Fabric does not feed through the machine
The feed dogs are lowered. Use the feed dog position switch to raise the feed dogs. 81
The stitches are too close together. Lengthen the stitch length. 42
The wrong presser foot was used. Attach the correct presser foot. 179
The needle is bent or blunt. Replace the needle with a new one. 34
The thread is tangled. Use scissors, etc., to cut the tangled thread and remove it from the race, etc.

what is the stitch length set to? should be 2.5 or thereabouts for normal serging.
Is the pressure foot pressure turned up too high perhaps?
The reasons I could think of for it not feeding through would be:
- the feed dogs under the pressure foot are out of position/not moving
- that the differential feed is turned up so its pushing the fabric back to the front of the machine
- stitch length is set very low so hardly moving the fabric at all
- or youv'e got a thread tangle happening around the foot/blade area.

I have a Simplicity serger SL880 that was my mothers. She past away about 8 years ago. I was trying to use it but appears the motor may be locked up that moves the feed dogs. Is there a place to oil it? If so where? Thank you.

From "Serge With Confidence" by Nancy Zieman:

Set the machine up for a 3-thread rolled edge. Normal width; length 1 - 2.

Use Woolly Nylon in the loopers & regular thread in the needle.

Lock or disengage the cutting blade.

Guide fabric along the right edge of the presser foot.

Stretch and equal amount from fron to back while serging.

Lower the differential feed, if available to about 0.6.

Serge at a slow to moderate speed.

Practice with scraps first.

After serging, gently stretch & release the fabric edge after serging.

The most common troubles with feeddogs not working properly is either lint trapped in between the feed teeth...remove the needleplate and clean out the lint which may look like felt in extreme cases. or... the presser foot tension is too low, in which case, increase tension...there will be a knob of some sort at the top of the machine directly above the Presser Foot Shaft. It is a remote possibility that the feeddog height needs adjusting ...it will have been a major trauma of a severe jam or tugging etc to cause this. As it would almost certainly result in other timings being affected and particularly in the case of a Serger/Overlocker, the added risk of breaking loopers (expensive), I would recommend a service by suitably qualified technician to restore all to optimum condition.
Best Wishes Martyn
Bargain Box in Australia