Sewing machine recommendations for canvas work?!

zig-zag stitching "triangulates" the thread contact points with the material and makes it less likely to move in parallel directions.
 
OK, we've only ever used straight stiches for canvas projects, although the machine can do zigzag. Why is it better to use a zigzag rather than straight stiches?

Because a line of straight stitches will not stretch compatibly with sail material when loaded. This will stress the beginning and end of the repair and not allow the material adjacent to the line to take up the shape of the material further away. Zigzag stitches allow close stitching for stength but because of the lateral distance between each stitch the seam can stretch.
 
Reading this thread with great interest as I am trying to repair spray hood
Would this machine do the job on canvas and sail material ?
http://www.ebay.co.uk/itm/131903078416?autorefresh=true
Item number 131903078416

I doubt it was ever marketed as a heavy duty machine and to call it semi-industrial is daft. You often see these sorts of fanciful descriptions.

However if might well work but there are problems. First of all it looks rough, it will be light in weight which means it will wobble about as you wrestle with the heavy fabric and, very important, the space under the arm is too small - what I think the American call the Harp size.

Something like his would be much more suitable in my view:

http://www.ebay.co.uk/itm/Singer-20...564985?hash=item33bd32f339:g:9LsAAOSwgZ1XrdZE

Only straight stitch though, but that is all you need for your covers and, If you harken to me, your small sail repairs as well:)
 
I'm in the process of altering and repairing a canvas winter cover using an old hand-cranked Singer 99K . I have put some patches on that need 5 layers to be stitched together and the machine has no problem doing this. A professional seamstress advised me to use jeans needles and these do make a big difference.

It would be useful sometimes to be able to have both hands free to hold two pieces of fabric in alignment but this is not necessary if you use 3/8" double -sided basting tape to fix the pieces together before you start sewing.
 
It would be useful sometimes to be able to have both hands free to hold two pieces of fabric in alignment but this is not necessary if you use 3/8" double -sided basting tape to fix the pieces together before you start sewing.

Although the tape makes life easy in some ways, it has the disadvantages of increasing thickness and, after a while, gumming the needle up. I used to have a hand cranked Singer but found it hard work compared to electric, even worse than the 60+ year old foot treadle Oliva I was using yesterday on curtain tapes.
 
If anyone needs a serious sewing machine, quite old, meal case, on a heavy duty bench with a big motor that is ideal for covers etc I will be selling one shortly.
 
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