DIYbanter - View Single Post - Has anyone here made a wooden folding loft ladder?

newshound

On 05/12/2019 14:19, wrote:
My house has a very large and boarded attic and I want to make access
easier by replacing a flimsy metal loft ladder that someone fitted in
place of an original wooden ladder. The existing trapdoor is quite large
(690x1450) so I'm tempted to make my own replacement ladder to avoid
having to put filler pieces in the ceiling - either a 3-section z-fold
or a 2-section slider. Making the ladder would be straightforward but
it's going to be heavy (especially when connected to the trapdoor, which
is timber framed and solid) and I can't see how to counterbalance it
safely. I could set-up 2 wires to pulleys on a purlin and use weights,
but the load will change as the ladder hinges down. Springs would change
their rate and probably do the job, but I can't see how to design the
mechanism and trial'n'error would be a pain.
I may give-in and buy an off-the-peg loft ladder, but it would be useful
to hear whether anyone else has tackled the same problem.

It's potentially quite a complicated design problem, a lot depends on
the clearance that you have above the hatch. A common way to cope with
the fact that load varies with geometry is to have friction somewhere in
the system. It's the sort of challenge that I quite relish, but then I
have been analysing mechanisms a bit like this for the best part of 50
years (usually when they are not working properly because of friction).
Even so, my starting point now would be to look at adapting a commercial
product.