I use sisal rope because it accomplishes the same purpose as tree bark. It catches the front claws so the cat can pull downwards and release the sheath to expose the new claw underneath.
I use 6mm sisal rope rather than the 1-2mm that other inferior products use because it is chunky, and is purrrfect for kitty to sink their claws into. It also helps Kitty to grip for that all important climbing.
The thicker rope size makes it more durable and longer lasting too.
My scratching post has a 110mm hollow centre. Which is important for how I fasten the sisal rope. It also helps to keep it lightweight which is important for a wall mounted product.
My technique for fixing the 6mm sisal rope allows for slight movement within the rope which is beneficial to your kitty and stops claw damage.
Which means I don’t use any glues or silicone to stick the sisal rope; because gluing the rope into place does not allow for proper movement of the natural rope, for when kitty is scratching/climbing.
Sisal rope is a natural fibre rope which means it is affected by moisture. If wet it will shorten and if dry it will lengthen. However it will be minimal especially when inside.
I do not use cardboard tubing in any of my products. My tubing is 110mm Industrial pvc tube. This means the post is suitable for outdoor use because it has a waterproof inner. Although if it is to be used outside it should be under cover.
I attach my brackets with 5mm pan head screws, nuts and spring clips. So they are solid and well attached. My brackets are very strong.
I use untreated sanded mdf discs for the top and bottom of the post. This creates a sturdy sitting platform. Should your kitty want to sit on the top. The discs are perfectly smooth. No risk of splinters.