In rebuilding some boat cushions. I'm having a little trouble with loose welting. I'll my stitching is nice and tight but when I sew the vinyl together with the welt it seems to loosen up. Any ideas?
Welcome to ya there, just to start off a bit can you describe how exactly you have or are putting the materials together. Is the welt pre sewn and just stands high afterwards or sewing some other way.
Good day
Are you using the correct size welt foot? A 5/32" welt cord takes a 1/4" welt foot. If you are making the welt up yourself. If it is premade welt you still need the correct foot to get next to the welt cord when sewing on the vinyl.
It's premade welt. The inner core is 5/32. I'm using a 1/4" welt foot. The stitch is in the correct place it just seems to loosen up. More when I go around curves or corners. I can see the stitches a bit when I stretch the covers over the foam.
You can try turning the smaller foot in a little being careful to still allow the needle to go through the hole.
First look at the premade welt (on the roll) to examine if you see the same characteristic on the welt.
If so, then it is sewn too loosely (welt foot was too large).
A work around would be to unsew the factory welt cord and sew it tighter with a foot size that tightens it up. If it tightens up, problem solved.
Just curious, what type filler is in the factory welt? It should be a hard foam core for marine. Probably is, sure you would have noted that.
Like mentioned before, probably due to factory technique.
Doyle
Sounds like maybe your thread tension is too loose? You say the stitches are in the correct position - That indicates to me that you don't really need to get the stitch line any closer to the cord. Is that correct? If you can see thread as you pull the face fabric away from the welt, your thread tension is too loose (or the bobbin tension - same result).
As for the corners, I'm betting the stitching is much better on the approach to the corner than just after you turn it. Try this - flip the work over and stitch from the other side just going into the corner.
What happens is that on the approach the needle is riding just where it should be along the welt and into the bend, but as you round the bend, the welt foot tends to push the welt away so you get an inch or so of stitching that isn't close enough to the cord. If you flip the work over and stitch in the other direction into the bend, it'll tighten up that side of the corner.
June