Slight confusion - needle/ thread size top and bottom

[RemingtonSteel]

Some of you may be aware that I am hopefully acquiring a Ferdco Pro 2000 this weekend, and if you haven't figured it out,  I am new to sewing leather with a machine.  So for the last several days I have been cramming in as much information as I can, about what I think I need to know about this topic.  One of the more confusing sub-topics is needle type as well as needle and thread size selection, but I think I have a pretty good understanding right now, with one point of confusion.

Wizcrafts states in the "Needles and Threads" pinned thread,

On 8/27/2011 at 12:14 PM, Wizcrafts said:

The weakest link in any project is the smallest diameter/tensile strength thread. Sewing with #277 on top and #207 on the bottom makes the stitch as strong as the #207 bottom thread.

and I believe this to be a sound statement.  Yet on Ferdco's website, I found some information on thread and needle sizing as well as in a pdf compiled by gtwister09 (great document by the way) in the "794 Machine Needles" pinned thread.  They recommend for Ferdco (and some other machines) one thread size for the top, and a one thread size down from that for the bottom, i.e. #25 needle, top thread #277, bottom thread #207.  So why do some manufacturers recommend this setup, while other suggest using the same size top and bottom as Wizcrafts mentions.

I have my suspicions on why this may be, but does anyone for know for certain why this is? 

What would the potential drawbacks be for me to run the same size thread top and bottom on the Pro 2000?

Any recommendations on thread type (polyester vs nylon, vs ...) and thread size for western holsters mostly consisting of 1/4" thick leather with welt upto a 3/4"? (From my research I am guessing polyester #277)

Is it generally a good practice to go down one size on the needle, over the recommended size to keep the holes in the leather smaller and would I be able to penetrate 3/4" of veg tan if I did?

Edited November 21, 2019 by RemingtonSteel

[Wizcrafts]

There are no drawbacks to using the same size thread on top and bottom. On the contrary, it provides maximum strength per stitch for the thread's rating. However, you have to use the larger of any recommended range of needle sizes. For example, to sew #277 thread on top and bottom calls for a #25 needle. A #24 will punch a tight hole that makes it hard to hold down the leather on the upstroke. If the leather lifts on the upstroke, you will get skipped stitches and ratted thread.

Sometimes you'll want to have a thicker thread on the top for appearances only, not to hold the project together against a lot of forces pulling it apart. In this case use a smaller thread in the bobbin, plus one size smaller needle and possibly increase the bobbin tension or back off the top tension to keep the knots from coming up too high.

As for the thread size in differing thicknesses, choose the largest thread that you can bury the knots so they are not visible from the top or bottom. For 1/4 inch, that could be either #207 or #277 thread. For 3/4 inch it would be either #346 or #415 thread. I personally limit my maximum thread size to #346 because it's hard to find #415 in anything other than black and white.

A 3/4 inch stack of veg-tan leather will tend to deflect the needle if it is too small. Use a larger needle to reduce deflection and poke a large enough hole for the knots to be centered without maxing out the tension and pressure springs. I use a #26 or #27 needle with #346 thread in any stack approaching 3/4 inch. This size needle pokes a huge hole, so stretch out the stitch length to no less than 5 to the inch.

One more thing is the strength of the pressure spring. It needs to be very strong to hold down 3/4 inch of leather.

All of these recommendations assume that the machine you are getting is actually capable of using these sizes of needles and thread and holding down thick stacks of leather. Can you test the machine before taking delivery, or will the seller run a test stack for you with heavy thread and large needles?

FYI: When I got my Cowboy CB4500 and when one of my buddies got a Cobra Class 4, there was a 3/4 inch stack of leather sewn off with #277 thread and a #25 needle under the feet.

Buy various sizes of needles and thread and see how things play out for you. It will take some adjustments to change thicknesses and thread sizes. You will learn this as you experiment and use your machine. Always keep leather scraps handy and sew the same thickness off as a test strip to get the knots positioned in the middle and the best looking stitch length.

[RemingtonSteel]

Wizcrafts,  thank you, lots of information to digest, but it mostly makes sense to me, except for this.

2 hours ago, Wizcrafts said:

This size needle pokes a huge hole, so stretch out the stitch length to no less than 5 to the inch.

When you stretch out a stitch's length, are you not decreasing the number of stitches per inch?  If correct shouldn’t the above be no more than 5 to the inch, or should I take that to read, anything less than 5 doesn’t look good?

 The seller has the original dealer sewn sample of several layers of leather at 3/4 inch that came with the machine when it was new. I’m not sure he knows what thread or needle size that was used as it was around 20 years ago and this was his father’s machine.

So my takeaway on this based on the holster type that I am making, I should do the following:

• Sew the lining to the holster leather (approx 1/4 inch) using 207 or 277 thread with appropriate needle size.
• Sew the two sides of the holster together with the welt in between (approx 3/4 inch) using 346 thread and size 26 or 27 needle.
• Keep stitch length between the two consistent.

Won’t using different size threads look a little off? With hand stitching, I always used the same size thread for.the entire holster and gun belt.

I guess with certain projects like this you just get used to changing needle and thread sizes.

[dikman]

Normal practice is to glue the liner to the outer layer. Once you've formed the shape (usually wet-formed) then it is stitched.

[RemingtonSteel]

1 hour ago, dikman said:

Normal practice is to glue the liner to the outer layer. Once you've formed the shape (usually wet-formed) then it is stitched.

I do glue the lining first, I was just summarizing the stitching steps to better understand how using a machine will differ from how I have been hand stitching.  

I don’t wet form, I form the shape during gluing by using a technique that I learned from Jim Simmons by following one of his tutorials. The rigs I am making are for Cowboy Action Shooting, so there needs to be enough retention to hold the gun through a large range of movement, yet still be easy to draw. I accomplish this by sandwiching a 1 inch wide strip of curved Kydex between the two layers of the holster.  This gives good gun retention, yet keeps the holster open when the gun is removed making it easy/fast to re-holster.

 

 

Edited November 22, 2019 by RemingtonSteel

[Wizcrafts]

3 hours ago, RemingtonSteel said:

When you stretch out a stitch's length, are you not decreasing the number of stitches per inch?  If correct shouldn’t the above be no more than 5 to the inch, or should I take that to read, anything less than 5 doesn’t look good?

Yeah yeah yeah, okay

[dikman]

That rig looks very nice. There's no right way or wrong way to make holsters, you use whatever method works for you. I find that if I don't wet mine it's extremely difficult to get it to fold over, plus the wetting/drying process actually makes it "set" quite rigid and I can easily make the holster with zero retention if needed, plus it keeps its shape.

It would certainly be easier if I didn't have to wet it.

If you're gluing the two layers then I can't see why you'd want to stitch them first?

[RemingtonSteel]

8 hours ago, dikman said:

If you're gluing the two layers then I can't see why you'd want to stitch them first?

Sorry, I guess I was having a hard time explaining myself last night... it was late and I may not have been thinking as clearly as I normally do. 

First, I moisten the leather along the fold area on the opposite side of the leather that the glue is being applied, to help minimize cracking or wrinkling. Then I glue the lining to the outer layer by curving the outer layer and slowly working the liner into the curve of the outer layer. Once glued, I then sew the entire piece except for the main seam. I then glue in the welt and sew the main seam.  There are various miscellaneous steps in between these, but I hope this helps to clarify my overall stitching process a little bit better. If you haven't check out Jim Simmon's tutorial (in pdf format) in the Holster forum, it is worth the read: 

One concern of this method is that it really pre-forms the holster into a nice curve and I am wondering how easy or difficult it will be to sew on a machine, but I am sure I will figure it out real soon.

 

 

[dikman]

Ok, now I understand. Sewing that curved part may be a bit of an issue on a machine, depending whether you can flex it open a bit to sew. You will probably need a holster needleplate, or maybe a stirrup would be better for that? I guess the best way will be to make a dummy section from scrap (not a whole holster) and try it first?