Introduction

While there is a variety of common wisdom regarding the effects of mechanical advantage and friction on suspension lift lines, the only published charts I'd ever seen attempting to quantitatively illustrate the subject were speculative and presented conclusions seemingly defying the laws of physics.

I've finally had some time over the past few weeks to explore this issue in more depth, first developing a mathematical model of the system, and then performing some experimental measurements to test the predictions of the model and determine the relevant coefficients of frictions. What follows are my conclusions from that work.

For background on the type of lifting setup which is discussed herein, please see this illustrated article.

Lifting Force

Let us imagine you are lifting a 100 lb bottom in a single-point suspension -- or, alternately, that you are lifting 100 lb worth of the body weight of a heavier bottom (for example, lifting their hips while their chest is...

I know some of you were having trouble watching some of the videos hosted on YouTube this past week; it looks like this was due to a recently introduced bug in the YouTube player used by some browsers, particularly Firefox. I've been able to work around the issue for now, so everything should be working again -- and I'm continuing to gradually move stuff over to Vimeo, which seems to be a more reliable platform.

Please let me know if you continue to have playback issues! Also note that for those on slow/unreliable connections, the video files can be downloaded for offline playback from my Vimeo channel.

I just added a feature (as suggested by one of you) to allow voting on what ties you'd like to see me cover next as I film more videos. Now when you go to a tie that doesn't have content yet, you'll see this:

Ties that get a lot of votes will move up in my video queue.

If there's a tie you'd like to see me cover that doesn't have an entry in the database yet, just let me know, and I'll add it so it can be voted on!

As I announced on Fetlife a few days ago, I've now finished posting all the required content to guide you through every step of performing your first rope suspension. To add that as a goal and have the system take you through everything step by step, just click this link and you'll join over 150 people already working their way through this free online course.

Do keep in mind that there's no substitute for in-person instruction, and it's always a good idea to have experienced supervision during your first few suspensions. My hope is that this material will improve the quality of information available to those without good local resources, but please don't go it alone -- if there's no expert in your area who can help guide you, at least have a couple friends with you when you're suspending to assist if you get into trouble.

This past week, I've been posting and updating a variety of articles and videos to help prepare you if you're working toward suspension.

My expanded rundown on hardpoint evaluation is a must-read for all rope suspension tops and bottoms; if you're going to be dangling from something, you really want to know that it's not going to suddenly drop you on your head.

I also wrote up an article on what goes into conducting suspension scenes safely, including technical concerns, good communication, and self-awareness.

Finally, I discussed how to select rope for suspension use, then illustrated with videos how to secure your support lines during a suspension, as well as other important aspects of support line handling.

Armbinders are a tricky tie -- they provide a wonderful feeling of restraint, but often cause nerve and circulation problems. The key to not having to untie your armbinder almost as soon as you finish it is to pick the right technique and level of strictness for your bottom's flexibility.

For escape artists and very flexible bottoms, the Extra Strict Armbinder can be made as restrictive as you could want, while still providing a lot of adjustability to get something sustainable.

When tying someone relatively flexible and not pushing the limits of their flexibility, the Basic Armbinder is a simple solution that works well as a component of larger patterns (such as hogties) because of its construction out of standard column ties.

For maximum comfort, and tying on people with limited shoulder flexibility, the Lace Up Armbinder is a beautiful tie full of creative possibilities. It can also be tied on numbers of arms other than two.

Over the past week I've been uploading a bevy of bedroom bondage videos to get you started with some hot restraint at home. One fan even already posted a story of a scene they had using one of these ties!

To start with, you're going to want to equip your bed for bondage. The tie in the story I linked above, which is great for transporting someone to a bed is the classic hands-behind-the-neck position. If you've already got someone on a bed, I showed a quick chest harness you can tie while they are lying down. And of course, if you've got a single or double column tie on a limb, you'll want to use a taut line hitch to tie it off to your bedposts or handy nylon tie-down loops!

Just posted are two videos on crotchropes -- one on a basic crotchrope you can wear out on the town, and another on how to use a crotchrope to attach a Hitachi Magic Wand for hands-free (or hands-restrained) vibrating.

It's really hard to overstate how much fun can be had with a simple crotchrope. On one recent occasion, I tied one on a date before going out to a party we thought wasn't going to include play; later in the evening when it did wind up turning into a play party, we didn't have any toys with us, but the crotchrope was just long enough to re-use to tie her hands up for a quick and very hot scene.

I posted videos this week of how to tie two versions of the classic Shinju chest harness; one is a more traditional variation which makes a good first technique for beginners to learn, the other is one of my own design that is optimized for suspension.

Also recently added are videos on the sheet bend technique I use to extend ropes, and how I keep track of the center of my rope.

I've added some new information to the CTKv4 article, including:

• A note on the size of the wrist cuff
• Explanation of the arm-wrap half hitch directions
• Some tips for tying on those with large breasts
• A section of links to related work

Ropeboi also pointed out to me that I failed to mention in the list of benefits of the split stem how much more comfortable it makes this TK for lying on your back in! BondageNexus posted a great photo illustrating this.