exxos's Atari, Amiga & retro forum

rubber_jonnie wrote: 12 Oct 2023 15:53 BTW, you said the chair has a foot rest, does that mean you never rest your feet on the floor? That could add a lot of extra stress at the top of the gas strut.

I bought the chair as it had a foot rest, thinking its a huge "lever" on the pison, so the chair *should* have been stronger. But it wasn't. I never use the foot rest even.

Incidentally that new piston I fitted not long ago seems be awfully wobbly as well. I doubt that will last much longer either.

Still going :hide:

exxos wrote: 12 Oct 2023 16:11 Still going :hide:


IMG_1394.JPG

Assuming that's 100% infill?

rubber_jonnie wrote: 12 Oct 2023 16:14 Assuming that's 100% infill?

Not exactly no. I explain something about this a few post back. Its only 10%, but I am using 20 outerwalls, so almost does the same job. But some parts in the center will soon show the 10% fill. Which is just as well because it is getting awfully "lumpy" there :roll:

exxos wrote: 12 Oct 2023 16:17

rubber_jonnie wrote: 12 Oct 2023 16:14 Assuming that's 100% infill?

Not exactly no. I explain something about this a few post back. Its only 10%, but I am using 20 outerwalls, so almost does the same job. But some parts in the center will soon show the 10% fill. Which is just as well because it is getting awfully "lumpy" there :roll:

Okey dokey.

Still going :roll:

Finally! Watch it not fit at all now :lol:

I think getting a metal one printed is a bit out of the question :roll:

Why not make up some box girder and attach it using a bolt going through the two sides of the seat frame and fit a reenforcing ring for the piston to fit into? Then, when it breaks you can unbolt it and fit another one.

stephen_usher wrote: 13 Oct 2023 13:17 Why not make up some box girder and attach it using a bolt going through the two sides of the seat frame and fit a reenforcing ring for the piston to fit into? Then, when it breaks you can unbolt it and fit another one.

Sounds like basically what it had before, though no idea about how it actually construct such a thing.

It would probably be cheaper to get a engineering place to make something out of aluminium.

Only other possibility , is to use this stuff which seems be about the strongest material and process.

https://3d.jlcpcb.com/help/article/200-PA12-HP-Nylon

EDIT
saying that..

PETG also has higher flexural strength at 70-90 MPa compared to 50-70 MPa for PLA+. These superior mechanical properties make PETG the ideal choice for high-stress applications like mechanical parts, tool handles, fixtures and functional prototypes.

So getting one made in China probably won't be much stronger than the ones I am printing now anyway.

Indeed "high-stress applications" :lol: