I got an email from my Gutermann rep; Germany, it seems, has relented and will now allow me to order my gimp by the spool instead of by the box per colour- a box containing 5 spools of 100m of gimp which would make, I guess, about thirteen thousand buttonholes. That's too much. Now if only they would relent on the silk twist as well.
UPDATE If you are located in North America and are interested in the Agreman gimp, a group buy is being organized on the C&T forum. Or you can contact me directly at jeffery_d at ymail dot com for more info.
In the photo above, on the far left, the large spool is my gimp of choice. I have always used this type of gimp but when Gutermann made it hard to get I tried a few different varieties and none even came close. Made in Spain, the article is called Agreman and is a wrapped core gimp which comes in spools of 100 meters. Richard James Weldon stocks this but shipping gimp from London to North America can be very expensive.
To the right of the gimp is my buttonhole twist of choice, Gutermann's silk R753, which is a size 40/3 long staple thread. More on this in a bit. It comes in 400m spools (like the one with the orange cob) and can be found at Ely Yawitz or Bergen Tailor Supply in the US. The box standing behind it is the same thread but in small cobs of 10m each; this is the retail format which is available from RJW (they told me they didn't have the bigger format) and is not really worth the money; a cone of 400m from Bergen is about $15 US, while the box of 10 cobs of 10m costs around $20 from RJW. Yawitz sells the individual cobs for about $2 or $3 so if you have a weird colour to do and don't want 400m of it, then the individual cobs are good for a two piece suit.
Second from the right is a one ounce spool of size F (Mara 30) long staple thread that I got from Bergen for about the same price a the 400m of R753. To far right is Gutermann's S1003 wihch is the same size but is a spun thread. Again, more on this in a second. This cone came from Dugdale and I haven't seen any of it in North America but is fairly common in Europe and comes in 300m spools; it is also available in size 40/3 (like the R753 but Dugdlae does not have it. Despite its being spun, it is about the same price as the long filament thread.
Not pictured is some continuous filament thread from Amann which Schneidergott sent me- it is the same size (40/3) but a shade more lustrous than the R753. He says it's hard to find over there (it's impossible to find over here). Maybe someone knows of a good source?
So which one to use?
First the difference between the spun thread and the long staple. When the silk cocoons are soaked to separate the fibers, the beginning and ends are shorter in length and are spun together to create the thread. Because they are shorter, the are more fiber ends which makes a fuzzier, duller texture. The long staple threads are made from the longer silk fibers from the middle part of the cocoon- the longer fiber means less ends and thus a shinier, stronger, and more lustrous thread.
The advantage of using a heavier thread, like the size F or the S1003 is that less stitches are required to cover the buttonhole, meaning less time and less thread. It is also easier to do a neat job using heavier thread. The buttonholes look a bit chunky compared to those using finer thread, so I prefer the finer. This is personal preference and one is not better than the other.
Examples of both size can be seen below; in each case I used the Agreman gimp.
This is the Gutermann S1003- the heavy spun silk. The size F thread would look the same, only shinier. This is a small buttonhole for a 24L button on a vest.
This is Gutermann R753 with the contrast punched up a bit so you can see some detail. This is also a small buttonhole for a 24L button on a vest.
And finally, the Amann 40/3 thread.
For details on how to make hand made buttonholes, see this thread