猎豹座椅

Summary

A seat for the LeaperKim Lynx.

This is a somewhat tall seat that slides forward when you need to operate the trolley handle, the seat adds around 6-7cm from the top of the Lynx, the top of the seat is meant to be soft but the lower part of the seat is firm and supportive due to a lot of walls on the inside.

I have learned a lot when designing seat for other wheels in the past and my goal when designing this seat was:

• Make a taller seat for better seated comfort on the Lynx.
• Make sure that even while being a tall seat it still doesn't hit my butt while jumping in the skatepark or doing other demanding off-road activities.
• Make sure the seat doesn't cut into my legs in any way while standing on the wheel.
• Make the seat soft and comfortable yet not compressing too much and overall giving good support.
• Make trolley operation easy and more comfortable.
• Create some sort of anti-slipping mechanism at the top so that the seat does not feel slippery.

The mechanism for sliding the seat forward is simple yet secure, it won't move by itself when riding but is still easy to operate. The seat rests on a bottom bracket which is attached to the wheel, there is a small lifting handle in the front of the seat that you use this to raise the seat a small bit and then slide the seat forward for access to the trolley handle. When you close the trolley you slide the seat backwards and push it down and it becomes secure again.

Before designing this seat I had the popular BD Seat which had some drawbacks that I wanted to address with my own design:

• Lower weight: The BD Seat is around 1kg (or 1.3kg with my 2cm riser that I designed), this seat is around 500g.
• The front of the BD Seat is designed in such a way that it can hit the inside of your legs while standing on the wheel, even more so with the riser I designed, this leads to pain in the legs over time.
• Trolley operation was not super comfortable the way the BD seat was resting against the trolley handle and didn't leave much space for your hand, it also felt awkward.
• Due to the aluminum folding part of the BD Seat I was worried what could happen if the wheel took a tumble, if the seat folds up while tumbling and is hit in the process then the stress from the impact will be transferred into the front handle of the Lynx, this can easily happen off-road and would cause damages that the Lynx would otherwise handle just fine.

Printing:

3D printing a seat can be tricky, you want the seat to be soft and firm at the same time, it needs to give you good support while also not feeling too hard, the filament is important too, TPU 95A is the best choice for this application but you can not use brands such as overture who makes way too soft filaments, I recommend using any other brand than overture when printing a seat, personally I use Yoyi TPU95A from Amazon which is both cheap and prints very good.

This print uses about 540g of filament with supports (depending on your support settings), the holes under the seat and supports for them are completely necessary to create a seat that feels good to sit on and I wouldn't recommend trying to modify that just to skimp on filament.

Print the seat either sitting on the print bed if your print bed is large enough or standing on it's rear if it doesn't fit your print bed.

My settings are based on a 0.6 nozzle but I will provide measurements in millimeters as well for those with a different size nozzle who wants to mimic my settings (which I strongly recommend).

TPU Brand: Yoyi TPU95A
Nozzle Size: 0.6mm
Layer Height: 0.3mm
Line Width: 0.62mm
Walls: 2 (0.62 x 2 = 1.24mm)
Top+Bottom Layers: 4 (0.3 x 4 = 1.2mm)
Infill: 5% Gyroid
Supports: Tree Supports personally I think tree supports are superior for this type of application, tree supports doesn't take as long to print, uses less material and are easier to remove, I use "Tree Slim" supports in Bambu Studio.

Installation:

As per the photos, clean the top of the Lynx with something effective such as Rubbing Alcohol and install Velcro, install Velcro under the bottom bracket, attach the bottom bracket to the seat first and then install seat and bracket together to get a good alignment, the seat should rest against the rear handle as flush as possible.