How to lock hands behind back?

[untitled]

As subject says

I bought an electronic time lock padlock, but aside from the general air of unreliability that makes me reluctant to trust it -  I'd rather have something that fails open if the battery dies - once the time runs out you have to press the release button, which I was kind of hoping would be impossible with hands sufficiently well bound and locked behind me. The whole point is to take away my dexterity, right?

I'm going to try putting an ice cube in a sock and tying it to the cuff d-rings, but thinking it may be escapable with simple brute force. (And if the sock is next to skin, it's going to melt faster than it did my trials hanging it from the top of the door, but for a first session that might be a good thing)

The MagBound looks very cool but not within my budget. The selfbondage-shop ice lock I could probably (pun unintended) stretch to.

Has anyone tried getting a 3dprint service to run off one of the thingiverse ice locks?

[Strappado]

I'd prefer a padlock between the wrists over the bulky ice lock, then ice away the key.

[Anne]

I still use this technique: https://www.likera.com/forum/mybb/Thread...-a-padlock

[TieUpTime]

I use locking leather cuffs. You can put a time lock on each cuff. Then a steel lockout hasp between them with another time lock (to keep the stress off of the lock shackle). Triple redundant!