u/throwaway_the_manual

Part 1

Per some comments about making it pony themed, the working title of this project is "Valerie's Predicament" as a nod to the sawhorse brand and certain donkey of discworld fame. The opportunities for bad puns and jokes about splashing were just too good to pass up. It's just the VP Bench for short.

This week was about figuring out how to make the saddle work in all positions (face up, face down, standing, kneeling, etc.) without putting pressure on tendons and nerves. The result is something like an extra wide bicycle seat with a big notch taken out of the center. When kneeling or straddling it facing out, your sit bones rest on the flared part so even though it's bare wood it more comfortable than you'd expect. Kneeling face down your ASIS are on the padded portion (white cloth in the picture) If I can figure out how to cover the exposed wood with a thin layer of padding I will, but there isn't much room to play with.

I got one of the pivoting arm/leg supports mocked up (pictured), and it works better than expected. I need to fabricate one for real and do some destructive testing since these are the aspect of the build where I have the most concerns about durability. While I'm busy breaking things for science, I also need to build a scale model of this thing to figure out the assembly order and design of the center beam.

When not in use, the plan is to raise the arm/leg pivots to full height (table configuration) and put a 3'x5' desk top on it, with a bit of faux-structural shielding underneath to further disguise it's true nature. While it will be modular and collapsible, not having to set up and break down every time would be nice.

Lessons learned:

1. Add some grab bars and foot pegs to assist with getting on/off. Lying down on your back atop this thing is fine once you're there, but getting up and down without falling off is challenging bordering on dangerous.
2. When using it face up there should be a solid cap on the end. A little extra width and a solid surface will make lying down easier and more comfortable.
3. Add an upper cross brace to the legs to keep them from twisting, but keep it low enough that it won't interfere with a wand/FL/dildo attachments
4. Even though having the knee braces tipped in slightly is more comfortable when kneeling face down, it makes other positions worse so it's probably better to keep everything parallel to the floor.

(Part 1)

I was planning to build the classic Versahorse, but after reading This post from a few years ago I decided to try the approach of starting with a simple frame and experimenting to find what actually works best for the people who are going to be using it. This prototype currently looks like garbage but I have already learned a ton. My ultimate goal is to come up with something similar to the Versahorse in it's ability to quickly set up or take apart and fit under a bed, but be better for actual fucking in terms of being able to put the user at the correct angle and height for both face up & face down use.

I'll update this as the build continues, but I've already learned a ton about ergonomics that seemed worth sharing. Feel free to ask questions or offer suggestions; I'm hoping to turn this into a how-to guide when I'm all done and I'd like the design to be as flexible and easy to modify for different body dimensions as possible.

Materials used so far:

• Burro brand sawhorse
• 1/2 inch plywood scrap
• 1x6 pine scrap
• foam floor tiles

The only thing I bought was the sawhorse ($40), everything else was scrap that I already had. If I'd had to buy everything new it would still have come in under $100. The burro sawhorse is slightly cheaper than buying the raw materials to build it and it gives you a place to start. The down side is that it's put together with staples and glue, so taking it apart is a bit of a pain.

Lessons learned:

1. The sawhorse (and versahorse) are too wide to comfortably straddle. As built, the top on both is a about 6 inches wide even before padding, which digs into your inner thigh if you are sitting astride it. This compresses some nerves and can cause numbness/tingling in a matter of minutes. I ripped the beam down to 3" wide, making the overall width 4.5" before padding. 3" between the legs allows plenty of space for hands or toys. A fleshlight won't quite fit, but there's room to mount it just below (pictured).
2. Whatever hole you are planning on fucking should be no higher than your pubic symphysis (the bone you can feel at the base of the penis or mons), and not more than 2" less than your inseam.
3. Bodies aren't symmetric front to back, so both the height of holes and the angles are going to change depending on whether someone is face up or face down. The vagina will be about 1" higher than the top of the bench when they are face down, and 3" higher when they are face up. The anus is the reverse, but has a similar amount of change. If the finished height of the bench is 2-3 inches less than your inseam you will probably be able to make all holes/positions work, but some may not be ideal.
4. Angles matter just as much as height. If the person is face up both the vagina and rectum slope down at roughly 30°, meaning the entrance is the highest point. If they're face down these both slope up at 30°, meaning the entrance is the lowest point. Having some means to control pelvic tilt such as a foam wedge or adjustable seat will make things better for everyone involved. Since tilting the pelvis also changes the height of the holes, this solves two problems at once.
5. You don't need (or want) thick, squishy pads. You want enough padding under knees, elbows, and sit bones to prevent bruising, but if it's too soft you again risk compressing soft tissue & nerves. The single layer of EVA foam floor tile material I'm currently using is too hard, but only barely. The goal should be something about the firmness of a bicycle seat or weight bench.
6. Openings in most sex furniture for hands/toys are way too big. I've noticed that a lot of bondage chairs or rideables like the monkey rocker have openings that are quite wide. This may make for a nice visual, but can be bad for the user. Your sit bones (ischial tuberosities) are the protrusions on the bottom of the pelvis that are designed to carry your weight when sitting and they're about 4.5" apart in men, 5.5" in women. Sitting for more than a few minutes on something with an opening wider than this puts pressure on surrounding tissues not designed to handle the load, and can compress the sciatic nerve. Sometimes called "toilet seat neuropathy" because that's the most common cause of this injury, it is unpleasant and can cause nerve pain that may take weeks or months to resolve.
7. The Burro sawhorse has an outward angle of 15° on the legs. This makes the horse slightly tippy when climbing on. The 20° used by the versahorse is more stable and feels a bit more natural.
8. The arm supports should be level with the floor, but the leg supports are more comfortable angled slightly in. If the leg supports are set level, you have to work harder to keep your knees from sliding out to the side.