Sewing A Flat Seam On A Bag

[thechavez]

I am looking for some advice on how to sew a flat seam on a bag. I have been sewing a regular seam on my bags by sewing them inside out with the grain sides facing each other, but I would like to know how to do a flat seam with grain side to flesh side so that the seams do not stick out into the bag. I current have a flat bed Consew, a cylinder bed Adler, and a post bed Pfaff at my disposal, but the trouble comes when I get to sewing too close to the base or when the bag is being sewn together on the second seam and doesn't fit under the machine. A good example of what I'm trying to do is shown in this photo. I'd like to have a flat seam on both sides of the bag if possible. Any advice would be greatly appreciated.

[25b]

...you are skiving the edges before you turn it over to sew the flat seam......right??

[dirtclod]

Look at a french seam if I'm understading what your asking right.

[ENC]

It looks like what you are talking about is a lap seam. The one you showed was done on a double needle machine, however you can get the same thing by sewing the (over)lap twice, but you wont get the perfect equal distance between the stitch lines that a double needle dose.

Ray

[thechavez]

Yes, a lapped seam would be what I'm referring to, wasn't sure if that would be familiar term with everyone or not. Essentially, what I'm looking for is some pointers on how to achieve a lapped seam on any particular machine, as it is a lot more difficult to maneuver than a standard seam. Is it helpful to tack at both ends, or how does one feed the piece under the foot while keeping the rest of the material out of the way? I'm guessing it just involves a good deal of cementing and tucking/folding along the way.

[ENC]

In any case I would glue the seam together first. If the bag is big enough and the leather soft enough you can feed it under the foot from back to front before you start stitching and then sew your way out of the bag. If not you need a "sew off machine" (or to stitch by hand). Its like a cylinder arm machine except the cylinder arm goes in the same direction as the feed. Some machines sew front to back with an arm that is perpendicular to the front edge of the table. Others look mostly like a normal cylinder arm machine, but sew right to left off the arm.

Ray

[Uwe]

A shoe patcher style cylinder arm machine (e.g. Adler 30-70 or Singer 29-4, etc.) will happily sew in any direction using a 360 degree swivel head without having to turn the workpiece. It's an option but it'll be tricky to do a double line of stitches perfectly aligned. If the leather is soft enough and the bag big enough, like in your photo, you can just fold/squeeze/wrestle the piece through a normal walking-foot twin needle flatbed machine, I suppose. Glueing the lap seam before sewing may be less aggravating but more time consuming.

I was admiring a Brooks Soho bag at a store recently. This bag has multiple lap seams and uses VERY stiff bridle leather. It's probably sewn by hand but I'm not certain. I am fairly certain that Brooks does NOT wrestle these pieces through a regular sewing machine, the leather is absolutely pristine on the finished bag. I'm not aware of a practical way to sew a lap seam on a stiff, cylindrical piece lengthwise unless you have a special machine that can sew in the direction of the cylinder arm, or by hand, as ENC mentioned before.

[kevinp]

Try this youtube channel he shows how to do french seams which are neater than the ones on the bag shown..

Edited August 30, 2015 by kevinp

[Uwe]

If the leather is thin/soft enough and the workpiece suitably big, a post bed two-needle walking foot machine might do a nice job for a lap seam on a bag. Apparently not many leather workers use post bed machines due to needle and thread size limitations. If you have $3,400 to spare, there's a nice Pfaff 1296 post bed machine for sale on my local craigslist.

The french seam approach shown in the video does not really solve the problem of how to sew a three-dimensional piece on a machine. Flat pieces like the ones shown in the video above are comparatively easy to do in both lap and french seams. French seam on a bag seems impossible unless you can turn the bag inside-out, which is not an option for stiff bridle leather.

[jesschyno]

What might also work is re-thinking the order in which you assemble the bag. For example, if you start your sewing from the bottom of the bag, then work your way up the sides (or the "walls", if you will), the lapped seam becomes easier to manage on a flat bed machine or a cylinder arm machine. However, you will probably have the most trouble using the flat bed machine.

Can you show us an idea of what the bottom of your bag will look like?