Same Thickness Of Thread On Both Sides

[oisee]

Hello Everyone,

I was wondering if anyone could help me and give me some insight.

As a small Swiss fashion company we have decided to produce leather belts and wallets. We are collaborating with Italian leather manufacturers. The first samples they sent us were great and exactly the way we designed and wanted them to be. Except for the seam. The thread hasn't got the same thickness on both sides of the leather product. To us that would be very important. especially for the wallet.

This is how we wanted the seam to look on the front and the back:

And this is how the sample came out.

As you see the thread on the back side is too thin.

After discussing this with our Manufacturers they unfortunately told us that they can't use the thread used on the front for the back aswell. They say their machines can't handle it and the thread always tears apart.

This is where I need your help. Is it normal for Leather Manufacturers to not be able to sew both sides with the same thread thickness? Are we demanding too much? I've seen many Leather products before witch same thickness threads on both sides.. Did we pick the wrong Manufacturers with very old sewing machines?

Maybe they just need to make bigger holes so that theres more space for the two desired thick threads?

I hope someone can help me with this issue.

Thanks already in advance for any help

Best Regards

Stefan

[Chief31794]

I'm not sure why they would tell you that they may have good reasons, I always sew the same thread on top and bottom and I've never seen goods that used different sizes. I've seen different colors for effect but not different sizes. I would check with other manufacturers.

Chief

[Dwight]

Here in the states, we call that "blowing smoke". That is they way they have developed "their" products over the years, . . . and don't want to change for your product.

There are some in the US who use for example 346 on top and 277 on the bottom. Mostly (I think) the justification falls in that they don't risk running out of thread in the bobbin as often, . . . as the bobbin can hold a lot more 277 than 346. Some also just like the effect, . . .

I don't like it for my stuff, . . . I use 346 or 400 top and bottom, . . .

Good luck, . . . may God bless,

Dwight

[Andrew Chee]

I'm not sure what size thread you are requesting but it could be that the thread is pushing the upper limit of what their machines are capable of sewing. In that case, using a lighter thread on the bottom lets them be able to use the heavier thread on top. With the correct machine though, there is no reason that you can't have the same thread on the top and bottom. The problem is probably because they don't have the heavier class of machines. Also bear in mind that the stitches on the bottom side will not look as nice as the stitches on the top. That's just a fact of machine stitching (unless you use a needle and awl machine).

Andrew

[Ferg]

To add and agree with above posts.

Normally, the reason for using a lighter weight thread in the Bobbin is to extend the time of use. Regarding strength, the strength of the stitch is determined by the lighter thread.

Also, in your pics, you show a straight line stitch in the first photo where as I assume the second image is the Italian stitch which is a Saddle stitch. They are accomplished with different style of needle.

I have one machine with a large bobbin, use same weight thread in both top and bottom. My Cylinder Arm machine has a small bobbin. In some instances I will use next smaller thread in bobbin.

The photo looks to have at least two sizes smaller in the bobbin, that is totally unacceptable.

ferg

[pault]

I agree with everyone else. If they had the correct machine for the job they could use the same size thread top and bottom.

[oisee]

Thank you very much for the quick answers. You were all extremely helpful! I now know what to communicate to the leather manufacturers.

To add and agree with above posts.

Normally, the reason for using a lighter weight thread in the Bobbin is to extend the time of use. Regarding strength, the strength of the stitch is determined by the lighter thread.

Also, in your pics, you show a straight line stitch in the first photo where as I assume the second image is the Italian stitch which is a Saddle stitch. They are accomplished with different style of needle.

I have one machine with a large bobbin, use same weight thread in both top and bottom. My Cylinder Arm machine has a small bobbin. In some instances I will use next smaller thread in bobbin.

The photo looks to have at least two sizes smaller in the bobbin, that is totally unacceptable.

ferg

A question to "50 years leather".

I can see now that the one stitching is straight and the other one isn't. I can also see that the holes are a lot bigger. Is it possible that the one in the picture above with the straight stitching is sewn by hand?

Best Regards

Stefan

[Ferg]

It is possible but highly unlikely since I have to assume these folks are mass producers.

ferg

[TwinOaks]

The pattern of the stitch, whether straight or angled, is determined by the type of needle used. Some needles will make a straight stitch, others will make an angled one. I sew with a 'Boss', and have two common needles available: 'S', and 'LR'.

As posted above, sometimes a smaller thread is used on the bottom to facilitate more thread in the bobbin...but there's another reason. The needle size dictates the maximum size of the thread, as the needle hole will be filled by 4 thicknesses of the thread....two sides of a loop, from the top, AND from the bottom. If the maker wants close stitching (a high number of SPI), then there is a limit to how closely the larger needle holes can be to each other before it perforates the leather. By using a smaller bobbin thread, a smaller needle can be used....which allows the stitches to be closer together.

[reddevil76]

I have a thinner bobbin (bottom) thread for one project. The sewn edge was a total of only 5 oz thick. The customer wanted a thick thread look, but with the thin edge, the knots would appear either top or bottom no matter how I adjust. The only solution was to use a thinner bobbin thread.

[Jwalker]

fantastic info in this discussion...thank you all for sharing!!

[Zandeosaddles]

very helpfull. i like the heavy thread handsewn look since i used to handsew alot. I have gone to a thin thread and thick needle on shoe patcher since the heavier needle deflects less and causes less friction on thread and allows thread locks to pull in easier. I use a pfaff treadle on my 12" patcher. bobbin is small and m36 thread goes further.