wavy piping

[SoInTrouble]

I have gotten through my first couple sets of seats.  These will go into my cars, I have been learning as I go.  I am having trouble with wavy, or puckering piping.  It seems to happen on some seams and not others on the main seam that holds the two halves of the bucket seats together.  I am using prefabed 1/4" piping.

I am wondering clipping the seam allowance vinyl as I go around bends will help. 

http://i1111.photobucket.com/albums/h478/sointrouble1/Upholsterydartfinished016.jpg

[gene]

Some people like to wave back, usually with only one specific finger, though.

Yes, clipping can help, but not fix the problem.

The two fabric panels are not sewn equally in length to the welt cord. If the welt cord in that section is 8" for example, one fabric panel may be 8" and the other may be 6".

Mark both fabric panels above and below the waviness. Take out the seams and measure between the two marks.

Search this forum also. This topic comes up on a regular basis.

Good luck, it can get frustrating.

Gene

[JuneC]

It looks like the white vinyl might have gotten stretched as you sewed the welting onto it.  Which piece of vinyl did you sew the welt to first?  Or did you sew all of the assembly in one fell swoop?  The seam is too long - so it waves.  Why it got too long can be difficult, as Gene says, to figure out.  Maybe one of the flat pieces is cut on the bias?  Maybe you "pushed" the welt core as you sewed?  What kind of core did you use anyway?  Looks rather firm, like the poly stuff. 

June

[SoInTrouble]

Thanks for the reply.  I will mark out 1"  increments on both sides of vinyl and check to make sure they line up as I sew the two halves together.  I did look through the archives and will try using the small black clamp line paperclips to secure the two halves together as I sew them.

Some people like to wave back, usually with only one specific finger, though.

Yes, clipping can help, but not fix the problem.

The two fabric panels are not sewn equally in length to the welt cord. If the welt cord in that section is 8" for example, one fabric panel may be 8" and the other may be 6".

Mark both fabric panels above and below the waviness. Take out the seams and measure between the two marks.

Search this forum also. This topic comes up on a regular basis.

Good luck, it can get frustrating.

Gene

[Mike8560]

id say there bolth right if you had reference marks on bolth the pieces they must have gotton off .
ill make reference marks and make sure they line.
up also with your pleats im sure you have sew foam back there. if the cloth is left on at the curve thats what causes the crease there

[SoInTrouble]

The Welting is the prefabed poly stuff, and I first sewed it to the back side, although for my latest set of seats I sewed both sides and the welt together at once and still had a little of the same problem.  I have been starting at the center of the two pieces, lineing them up and sewing them, then flipping the cover over, starting at the center again and going down the other side.  I might try marking both sides in 1" increments and then going from one corner. 

I am wondering about marking the edge, if it is a curved section, it seems like you would want to measure along the stitch line, 1/2" in, or you will be short on the left hand turns and long on the right hand turns.

It looks like the white vinyl might have gotten stretched as you sewed the welting onto it.  Which piece of vinyl did you sew the welt to first?  Or did you sew all of the assembly in one fell swoop?  The seam is too long - so it waves.  Why it got too long can be difficult, as Gene says, to figure out.  Maybe one of the flat pieces is cut on the bias?  Maybe you "pushed" the welt core as you sewed?  What kind of core did you use anyway?  Looks rather firm, like the poly stuff. 

June

[stitcher_guy]

clamps aren't strong enough. You don't realize it because it spreads out over the whole expanse of the seam, but the piece of material cut on the bias (it's stretchier) is lengthening as you sew. Get a heavy stapler and staple the pieces together every few inches to hold it all together. ALSO, or instead, when you sew, do not hold the pieces (upper and lower and the welt) and do not pull it into alignment. Any little thing will stretch it.

What I do is push down onto the sewing bed to hold all parts together, and let the feed pull the material through all at the same time. I will even push down and slightly forwards, towards the needle to take all tension off of the panels and keep anything from stretching. It happens the worst with vinyl, but also with other materials. It's something you have to really be aware of all the time

[SoInTrouble]

Thanks for the help on this.  I pulled apart the two halves, trimmed about 1/16 to give the needle some fresh vinyl, marked 1" increments on both pieces, and stitched them together.  I noticed some improvement, and was surprised at the amount I had to push and pull the material to line up.  I pulled it all apart and did it one more time this time trying to use only compression to line up the marks.  It came out fairly well. 

I did notice that the Bias was 90 degrees of on the pieces that I was having trouble with, and I will make sure that I cut the pieces with the bias in a way to minimize stretch along long seams.  In addition this vinyl had a lot of stretch to it.  I will avoid that in the future.

I was trying to squeeze out the max number of panels of the vinyl and didn't pay attention to the bias.  Lesson learned. ;D

Thanks again.

[Mike8560]

Great! I also only pinch the material and not try to ouch or drag the mater going to the needle unless I want too 

[DBR1957]

Our seamstress used to get wavy seams when she would make the welt. Turns out she set the spool on the floor and just pulled the cord as she went. Once we placed the spool on a rod and let the cord roll off the waves went away.

One trick with wavy seams is to steam from the inside. I've recovered many an odd shaped boat seat or cushion with a compound curve and steam smoothed everything out.