I have been asked if I could do minor repairs to a leather jacket by a friend. It looks like the zipper is just coming unsewed at the bottom. My question is regarding my machine.....a Janome 6600....taking into consideration the thickness of leather, will my 6600 be able to sew through all the layers without stressing or damaging my machine? There will be the outside layer of leather, edge turned under, ....then the zipper....then the inside facing which is another double layer of leather. The repair itself is simple, but is the machine strong enough? What thread would I use? Thanks in advance for your advice and knowledge.