Appropriate Sewing Machine For Watch Straps

[Wizcrafts]

4 hours ago, Sticks said:

Hi there,

 what is the feed system on the 31-15 ? How does it feed without marking the leather?

I actually need a machine to ONLY make the holes so I can then handstitch.

 

The 31-15 is a drop feed machine, via feed dogs on the bottom. The presser foot is static. The feed dogs will mark the bottom layer, with the depth of marking dependent on how much force is needed to hold the leather down during the upstrokes. But...

I doubt that a 31-15 will be able to hold a needle large enough to punch holes for hand sewing thread. It is a tailoring machine that normally uses small needles, up to #22. It would take a #25 or #26 needle to make a large enough hole to pass typical hand sewing thread (no wider than #277 machine thread). This would require a throat plate with a greatly enlarged needle hole and the removal of the bobbin case (and possibly shuttle driver), which would be impacted by the oversize needle.

I sometimes use my Cowboy CB4500 with a #26 or #27 needle to punch hand sewing or tiny rivet holes. You are going to have to set your sights a lot higher than a Singer 31 class to punch such large holes

[dikman]

I've hand stitched by pre-punching the holes using a #21 needle to give me even spacing and then used an awl to widen the holes for stitching. I'm assuming this is what Sticks intends to do?

[Wizcrafts]

1 hour ago, dikman said:

I've hand stitched by pre-punching the holes using a #21 needle to give me even spacing and then used an awl to widen the holes for stitching. I'm assuming this is what Sticks intends to do?

If that is indeed the case, the 31-15 will accept a #22 needle that can lay down evenly spaced holes that can be enlarged with a hand awl. But, the throat plate a large hole plate. The fine plate won't pass a #22 needle. The standard plate "may" clear it, if the needle doesn't get deflected at all by the strap. The large hole plate has enough clearance to deal with needle position inconsistencies.

FWIIW: The large hole throat plate is usually sold with a matching larger feed dog as the "heavy duty set.". This may be too aggressive on the bottom layer, so I would try to keep the existing (fine/standard) feed dog in place, unless it won't physically fit into the throat plate's slots.

An even better solution would be to obtain a straight stitch machine that is already setup with a roller foot and large hole throat plate.

[Wizcrafts]

15 minutes ago, Sticks said:

Thnx for the replies guys.

Actually the holes I need really need to be small as I mainly use 832 and 40s thread .

Wiz,can you comment on the singer 138w101 post machine.? What feed system does this use.?

Is this any good to a watch strap maker.?

You'll have to ask a dealer about that one as I have no experience with that model. The only info I see relates to double needle machines, with a 3/8" gauge between the needles.

I can tell you from my experience in the distant past that Singer post machines used light weight thread and small needles.