Harness needle in relation to thread size

[RemingtonSteel]

I am having a little difficulty pulling the eye of a size 2 John James harness needle through 14/15 oz of leather, and thinking of using a smaller needle.

1) Ritza supposedly recommends a size 1 harness for their 1.0 mm thread and I am using a size 2 harness needle. So my main questions is:  Are there any drawbacks/problems associated with using a smaller needle than recommended, or is it just a matter of if you can get the thread through the eye of the needle you are good to go?

2) Looking at John James website, they list the following sizes for harness needles:

Size 1 55mm length x 1.02mm diameter
Size 2 55mm length x 1.02mm diameter
Size 3 55mm length x 1.02mm diameter
Size 4 48mm length x 0.86mm diameter
Size 18 (1/0) 57mm length x 1.09mm diameter
Size 17 (2/0) 60mm length x 1.42mm diameter
Size 16 (3/0) 62mm length x 1.63mm diameter

I am wondering since the length and diameter of the size 1, 2, and 3 needles are exactly the same, could the difference between them be the size of the eye (size 3 having a smaller eye than size 2)?  

3) Lastly,  Is anyone using a size 3 or 4 needle with Ritza 25 1.0 mm thread? 

 

[Matt S]

A no4 needle should be fine with 1mm Tiger, since it's so flat. At £2 a pack it's got to be worth a go.

How are you stitching? 16oz is about 6mm, which isn't so very thick. A no2 needle shouldn't be much trouble.

[Tugadude]

Just as important is the size awl you are using.  If not using an awl, you might want to because it temporarily stretches the holes, making passage of needles easier.

[plinkercases]

Agreed on the awl size... on thicker pieces I will even run the awl to the round and stretch the whole a little.... it come back to diamond and closes up as usual.

And use the trick about using the first thread threw to pull the second needle threw which is a finger saver when remembered....

[motocouture]

For info, I use the size 4 needle with 0.6mm Tiger thread, and the size 2 with 0.8mm Tiger thread.  I'm generally sewing 4-5 oz leather, but doubled with folded piping in between it's probably getting close to 14-15 oz equivalent.  I definitely found the size 4 needle easier to pull through. 

[RhodesAveDesigns]

Here's my .02 (from someone with a card wrapped in "extra" pieces of wasted/shredded thread). 

The #1, #2, and #3 needles are all exactly the same; JJ and some resellers have included explanations for "why" (which are somewhat convoluted, and have something to do with different # systems and size expectations in different areas). 

In my experience, trying to use a needle size which is too small for your thread will shred your thread at the eye, if you can actually thread the needle at all. A smaller needle may be "easier" to sew your leather, but having to stop constantly to "fix" your thread (and losing some of your thread length) will not help speed up/ even out your stitching process. While Tiger thread is pretty flat, this doesn't necessarily mean it will fit through all needle eyes, and 1mm will not work well in a #4 needle (and you may break the needle at the eye). 

As others have pointed out, you should utilize an approriately-sized awl (or a different chisel size or type), rather than try to compensate with your thread/needle combination. Unfortunately, until you own nearly "everything" available, this may mean needing to pause your project until you have a better combination of supplies.  

- Elizabeth

[zuludog]

As far as I know, the reasons it is difficult to pass a thread through leather are

The needle is too thick

The thread is too thick, causing extra thickness where it folds over at the eye

The holes in the leather are too small

Any combination of these

Now; a #2 needle is one of the larger sizes, but is still very common in leatherwork

1 mm thread is a thick - ish thread, but again not excessively so, and I should imagine that this combination is one of the most commonly used in leatherwork

So it could well be that your holes are too small. As suggested, use a bigger saddler's awl or enlarge the holes with a round awl. if you use a round awl the holes should close up afterwards and revert to their original size & shape. If you use a larger saddler's awl and the holes look like they might join up and run into one another then your spacing could be too close together. I'd say 3 to 4 mm is about right for your combination of thread & leather thickness

You should be able to push or pull a needle & thread through leather by hand about 95% of the time, with just a slight resistance or satisfying drag. The exception is when you are backstitching, but even then it shouldn't reduce you to blood & tears. Try using small pliers with the jaws wrapped in masking tape to prevent scratching the needle

Whether by hand or with pliers, if the needle becomes stuck, use a straight pull. Resist the temptation to wriggle it about or it may snap at the eye

[zuludog]

Have a look at this video by Nigel Armitage on YouTube - 'Saddle Stitch in Detail'. Between 3min 40sec and 4min 30sec he describes the different sizing systems for needles in UK and USA

It could well be that you know you need size 2 John James needles, but when you have asked for them in USA you have been given USA size 2, which are bigger. The video shows this quite clearly

 

Edited September 9, 2017 by zuludog