Can i sew a patch on my down coat ? I have been told it will cause my jacket to leak around the stitches

I don't know about your specific machine, but in general for heavier fabric, increase the pressure on your pressure foot and reduce the length of your stitches.

Your gonna need a machine with a over locker on it.

Use the reverse button. That's what it is for. Sew forward and then push the button and sew in reverse.
Machine Darning Jeans Shirt

If you have a darning foot, you can use it (drop the feed dogs) and then you manually move the fabric around while stitching.

Learn How To Mend Clothes with Machine Darning

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That sounds pretty heavy for your machine... yes try your walking foot attachment AND a longer stitch

check with leatherworker.net & ask them

Subject verb agreement. No one in our group has a jacket

I do not know what machine make and model this is.

But I darn the following way.

Iron onto the back of the hole/rip a piece of iron on mender in a similar colour and weight to your garment, allow just a centimetre extra around the rip. Try to bring the edges as close together and neatly as possible before ironing to attach the patch behind.

Now set the machine to a three step zig zag stitch, stitch width to the maximum and turn stitch length down to about .8 or so. Now sew over the rip/tear area fillling in the damaged area reversing back and forwards to cover the damage and a good margin around it. I use a colour matched thread if I can to make the stitching less obvious.

Done!

Hi, if you check your local outdoor shop you will find self-adhesive gore-tex patches for shell garments - you might even get the right colour. As they are made for outer shell garments they stick well and are not affected by rain etc.

This is caused by a bent needle. Try a different needle that is straight. When they get the slightest bed in them the stitching will end on the back side only

Yes, if there is an iron-on adhesive being stitched over.

A bead of Sewer's aid along the seam line in advance of stitching will keep the needle clean - but, with tulle, it may not adhere.

Try it on the top thread by running a bead of SA down the side of the spool to lightly coat the thread.