Here is a close up of the end of one leg of the breeches in the museum. It is a plain band that encircles the leg and there is nowhere to put a tie if you wanted one. In fact there is no need as the breeches are cut to fit the leg below the knee. So had I got this one wrong? I needed to look at some more evidence.
I wondered (as all the conventional wisdom I'd heard suggested that leg ties were used in the 1640s)s if looking at pictures might help solve the problem. I went to the 1640s Picturebook blog and clicked on the "breeches" tag to examine the pictures that had a decent image of the lower end of a pair. I took no notice of the status of the wearer, just the finishing of the breeches. If you are so minded, you can look for yourself by following this link. What I found was five basic types, examples of which I have copied below. As of time of writing there are 85 such images on the blog.
The first most numerous type is basic gathered legs with no visible ties or decoration. The type that is probably gathered into a small band. The example is from the English Improver Improved 1652. This type appears in 47% of the images.
The second most numerous is breeches legs ungathered but decorated in some way, usually with ribbon though buttons make an appearance occasionally. 25% of images in this case. This example from The School of Artificial Fireworks 1658.
Third on the list shows breeches legs tied around with tape or ribbon, where the tapes pass around the outside of the leg. In this case the breeches can be gathered by the tape, but the tape is not a part of the breeches. 13% of the sample. This picture is from Corpus Sine Capite Visibli 1642.
Just left ungathered, no decoration 8%. James Naylor's torture from 1656
And the final section where it just looks like there may be leg ties attached to the breeches, but I suspect from the weight of statistical evidence that the bows are more likely to be garters to keep the hose up. 7% Shepherd's Oracles 1645
I'm convinced now that leg ties were not used on 1640s breeches, nor were they actually necessary. What you did need though was something to tie round your hose to keep them up. This I believe is the origin of the leg ties seen worn by some reenactors of the period.
Sometimes however things move quickly in reenactment. This quote was pointed out to me today. It's from the National Archive and contains the toughest of George Wood from 1645 on the costings of suits to be made up for the standing army. The reference number is SP 28/33 f 443
If the State allow 17 shillings for a cassock and a pair of breeches (that the two may be made according to the usual sizes formerly made for the furnishing of the several magazines I humble contrive it for quality and quality the two ought to be and worth in ready money, viz,
4 yards of Northern kersey at 3s and 6d per yard
or proportionally 2 yards ¼, 1/16 1/32 of broadcloth at 6s
1 yard ½ of lockram at 12d per yard
1 pair of pockets at 3d
In tape for binding the cassock and knee strings 2d
In hooks and buttons for the breeches 1d
For making of the cassock and breeches total 17s
For the making of a cassock and a pair of breeches there will be requisite as follows according to the samples I have seen I humbly contrive them to be in quality and quantity and worth in read money
3 yards ½ of Northern kersey at 2s per yard is 7s
1 yard ½ of linen cloth or lining the breeches 9d
1 pair of leather pockets 3d
In tape for binding the cassock and knee strings 1 ½
In buttons and hooks for the breeches 1d
For making the cassock and breeches 10d
4 yards of Northern kersey at 3s and 6d per yard
or proportionally 2 yards ¼, 1/16 1/32 of broadcloth at 6s
1 yard ½ of lockram at 12d per yard
1 pair of pockets at 3d
In tape for binding the cassock and knee strings 2d
In hooks and buttons for the breeches 1d
For making of the cassock and breeches total 17s
For the making of a cassock and a pair of breeches there will be requisite as follows according to the samples I have seen I humbly contrive them to be in quality and quantity and worth in read money
3 yards ½ of Northern kersey at 2s per yard is 7s
1 yard ½ of linen cloth or lining the breeches 9d
1 pair of leather pockets 3d
In tape for binding the cassock and knee strings 1 ½
In buttons and hooks for the breeches 1d
For making the cassock and breeches 10d