Breaking and bending needles in foam

[Patrick W]

I am sewing backpack straps that are composed of a layer of 330d cordura and 3D mesh, with 1/4 closed cell foam sandwiched in between.  I am trying to add the necessary webbing but I keep breaking needles.  I have gone up to #16 and down to #9 but that doesn’t seem to matter.  I’m using gutermann tex 40 thread.  Any thoughts?

[Jerry Adams]

I’ve dome that before

It seemed like it helped to go slowly and let the foam go through the machine without touching it

Normally, I pull on fabric from both sides to put a little tension on it to keep it flat, but with foam that will cause the foam to move a little which breaks the needle

[Jerry Adams]

longer stitch length?  shorter?  different thread?

[Patrick W]

I have varied the stitch length, which made no difference. I have not changed thread because the gutermann thread is the only right sized thread I have.

I’ll try to be less active with the movement of the straps/belt through the machine.

[Kattt]

Is your sewing machine made to handle what you are feeding it through?

[Hoosier T]

I had the same problem. In my case the feed dogs were moving the straps too fast so the needle was getting bent as it went through the strap causing it to hit the base plate. I had to do mine mostly by hand using the wheel.

[Jerry Adams]

I have a Janome home machine that is most definitely not made to do something like foam, but I can make it do a little.  If I did it for a living I’d get another machine for heavy stuff.

 

[Daryl and Daryl]

Wish I could pinpoint the problem but I can’t.  Sometimes my home machine can handle foam sewing with no problems and sometimes it can’t.  I don’t know all the variables.

My experience is that 1/4″ foam sandwiched between two pieces of smooth nylon usually sews without problem.  So I’m thinking that the 3D or the cordura may have complicated things.

Do you have some scraps to experiment with?  Have you tried it with the mesh on top as well as the bottom?  How do things sew if you remove the foam altogether and try sewing cordura directly to 3D?  Just trying to sort out/isolate variables here.

 

 

[Nick Smolinske]

Before I had industrial sewing machines, if I was sewing webbing through a shoulder strap with foam like that I would just use my Speedy Stitcher (aka a hand sewing awl). Slower but you only need to do one pass since the thread is so thick.

[Jerry Adams]

maybe sew the webbing to the fabric, make a tube for the foam to go into, and then stick the foam in without having to sew through it.  Maybe put some hand stitches through foam just to stabilize things.

[Patrick W]

Lot of good thoughts!  My machine is a 70s era Kenmore.  Built like a tank.  I doubt the designers expected it to be used to make backpacks, but it’s sturdy enough.

At this point I have sewn the straps and belt closed, with foam inside.  The stitching going on now is sewing the webbing on the cordura side of these items.  I suspect that the stretchiness of the 3D mesh is not making this easier, but I have to keep the cordura side up now.

The idea of the feed dogs moving the strap/belt before the needle can extract/insert itself–causing the needle to occasionally strike the base plate–makes sense to me.

I am waiting for an order of webbing to arrive so I have a couple of days of working on other parts of the pack. When the webbing arrives, I’ll try to notice if the needle is striking the base plate.

I was wondering if anyone in a similar situation had tried soap or wax on needle to get it moving through the foam faster.  Could be messy I guess.

[Nick Smolinske]

Jerry, I’ve tried that and I found that the tube just rotated around the foam. A couple stabilization stitches might help but sewing the whole strap through the foam is definitely better.

[Jerry Adams]

same here, foam moves inside the tube.  A few hand stitches would be better than nothing.  At least as an experiment.

[Jerry Adams]

I’ve had the needle hit the baseplate and break before

[Ken M]

If I have this correct,  your layers from the bottom up are mesh. foam, cordura, webbing.

1)   Total thickness is probably thicker than the presser foot was made for but you can still get the wad underneath.  This makes for a tight fit…lots of friction.  Try loosing up the pressure on the presser foot.

2)  The mesh is probably just stretching as the feed dog tries to pull it through.  too much friction on top may aggreivate this.  Try putting a sheet of paper on the bottom and see if it might (?) give the feed dogs a bit more grip.  Or possibly try a layer of masking tape on the mesh…essentially just adding a firmer surface that you can remove later.  There is some rip-off backing for embroidery work that you would probably at Wmart or fabric store if any are handy.

3)  Another thought…  If above doesn’t help and you still break needles…  Lower the feed dogs so they can’t pull.  Needle down,  needle up and clearing the fabric,  pull the fabric a bit,  repeat one stitch at a time.

Hope something helps.

Ken

[Jerry Adams]

maybe flip the lever to raise the pressure foot and see if that works

if you have to have one side on the top. maybe put some hand stitches to keep everything aligned, then turn it upside down

[Roger Caffin]

maybe flip the lever to raise the pressure foot and see if that works

BAD idea. It won’t work.
You see, when you raise the pressure foot you also take the tension off the top thread. The stitches will be loose and tangled.

Sometimes you just have to accept that a particular sewing machine has limits to what it can do. Sew the foam-free bits with the machine, then hand-sew the foam bit (if they must be sewn).

Cheers

[Jerry Adams]

oh

just looking at machine, yeah, raising pressure foot lever releases top tension

you could still try it, maybe with no top tension, with foam, it would work better than nothing…

[Patrick W]

I should have mentioned that I have the adjusted the foot pressure for the least possible pressure.  I like the idea of tape.  I have some blue painters masking tape on my table because I use it sometimes to hold things in place.  I could run that under the belt and see what happens.  Some great ideas!  I truly appreciate the help.  Thank you!!

[Lester Moore]

Patrick – what type of needle point are you using? I had similar problems on my latest backpack and had to switch needle types, and that worked. The Microtech needle that works well for all the main pack seams was causing jamming and all kinds of problems with shoulder straps.

Another thing that solved the problem which I did not need to keep doing was to cut small elongated rectangular holes in the foam to perfectly match where you want to sew your webbing bartacks. This makes is easier for the needle to stitch through the webbing, top fabric and spacer mesh without any foam in the way.

They key is to experiment and find what parts (needle size & type and thread size) and conditions (tension, length) work for which combo of fabrics.

[Roger Caffin]

blue painters masking tape
Caution.
I found that the needle picked up the adhesive from the tape, so that the eye of the needle got all gummed up. Then the thread got gummed up as it whistled back and forth through the eye. Then the thread jammed and the needle broke. YMMV

Cheers

[Patrick W]

Thanks for the tip on the blue tape.  Don’t need to do that.  I’ve used a double sided tailor tape a bit and had that same problem when I sewed directly over the tape.  Very frustrating.

As for needles, I am using two brands, Kenmore and Organ, of various sizes.  I don’t notice a performance difference in the two needle brands.  Broken some of both.  Yes, I’ll be doing some experimenting for sure.  Got to find a way through this.

[Paul McLaughlin]

I have had the same issue. For me it is mostly about the thickness of the foam and the limitations of the presser foot’s ability to compress it. Thinner foam no problem, thicker or denser foam and trouble. I suspect, as has been mentioned above, that it has to do with the needle still being engaged in the piece while the feed dogs advance the piece, and/or becoming engaged before the piece has stopped moving. What I have always done to deal with this is to hand crank the machine through these seams. Slow, but faster than hand stitching for me. I suspect that industrial needle feed machines solve this problem but have never used one.

And by the way I have had the same thing occur with thick combinations of fabric and webbing. Used to be pretty common issue for me back in the days of sewing 1000d cordura and thick seatbelt webbing. Not a problem with lightweight fabrics and skinny webbing

[Roger Caffin]

Could be right Paul. Could also be that the foam drags too much on the thread during the retract.
I use an ELNA TSP for light fabrics, but not for heavy ones. For webbing and heavy fabrics I use an old black Singer – straight stitch only, but it goes THROUGH the heavy stuff. Mind you, the ELNA has a #60 needle while the Singer has a #100 needle.

Cheers

[Sam C]

I have experienced similar issues in the past.  A #110/18 Heavy Duty Singer needle solved the problem.

[Author]

Posts