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.

My main problem is all the muck that comes down when you open it.
Its one of those concertina ladders.
Brian

--
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This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
wrote in message
...
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.

We had a 3 fold z type at the last house cannot remember who made it but it had some spring assistance to heave it up but I did get to think as I got older it became harder to push up and certainly not a job for a little old lady!

Richard

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.

On 05/12/2019 16:11, newshound wrote:
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.
Clearance isn't an issue; the hatch isn't at the centre of the span but
there's no shortage of space above it.
I've been looking at commercial mechanisms and spare parts, but mine
will be heavier (mostly because of the door and because I want to make
the steps as wide as possible). There seem to be lots of spring design
websites but I've no idea how to estimate the required spring force.
The answer might be to use off-the-peg bits and to keep adding springs
until the weight is roughly balanced, but the loads on the attachments
might get worrisome.
With all the other jobs in progress I'm not exactly wanting another, but
it's a problem that needs solving and it's useful to gather info.

On 05/12/2019 18:14, wrote:
On 05/12/2019 16:11, newshound wrote:
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.
Clearance isn't an issue; the hatch isn't at the centre of the span but
there's no shortage of space above it.
I've been looking at commercial mechanisms and spare parts, but mine
will be heavier (mostly because of the door and because I want to make
the steps as wide as possible). There seem to be lots of spring design
websites but I've no idea how to estimate the required spring force.
The answer might be to use off-the-peg bits and to keep adding springs
until the weight is roughly balanced, but the loads on the attachments
might get worrisome.
With all the other jobs in progress I'm not exactly wanting another, but
it's a problem that needs solving and it's useful to gather info.


I have a loft ladder which is similar to the Youngman's 3 part one that
you can find with google. There are no springs. To raise the ladder you
push up the bottom two sections so that the bottoms are level with the
bottom of the top section. You then use a pole to push (tip on the
hinge) all three sections up into the loft where their weight keeps
them level with the loft floor. The pole is needed to gently pull them
down.

--
Michael Chare

I use aluminium ladders sawn off to size at my loft hatches
(which are long and thin)

[g]
On Thursday, December 5, 2019 at 2:19:17 PM UTC, 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.

On Thursday, 5 December 2019 18:14:20 UTC, wrote:
On 05/12/2019 16:11, newshound wrote:
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.
Clearance isn't an issue; the hatch isn't at the centre of the span but
there's no shortage of space above it.
I've been looking at commercial mechanisms and spare parts, but mine
will be heavier (mostly because of the door and because I want to make
the steps as wide as possible). There seem to be lots of spring design
websites but I've no idea how to estimate the required spring force.
The answer might be to use off-the-peg bits and to keep adding springs
until the weight is roughly balanced, but the loads on the attachments
might get worrisome.
With all the other jobs in progress I'm not exactly wanting another, but
it's a problem that needs solving and it's useful to gather info.

If you're not short of headroom just use a 1 piece ladder with weight on a pulley.

When using multisections the pulley mech doesn't need to balance it, just needs to keep it within workable limits.


NT

wrote in message
...
On Thursday, 5 December 2019 18:14:20 UTC, wrote:
On 05/12/2019 16:11, newshound wrote:
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.
Clearance isn't an issue; the hatch isn't at the centre of the span but
there's no shortage of space above it.
I've been looking at commercial mechanisms and spare parts, but mine
will be heavier (mostly because of the door and because I want to make
the steps as wide as possible). There seem to be lots of spring design
websites but I've no idea how to estimate the required spring force.
The answer might be to use off-the-peg bits and to keep adding springs
until the weight is roughly balanced, but the loads on the attachments
might get worrisome.
With all the other jobs in progress I'm not exactly wanting another, but
it's a problem that needs solving and it's useful to gather info.

If you're not short of headroom just use a 1 piece ladder with weight on a
pulley.

When using multisections the pulley mech doesn't need to balance it, just
needs to keep it within workable limits.

Havent seen too many roofs with that much room.

He did say its not at the peak of the roof.

On Sat, 7 Dec 2019 03:09:54 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH troll****

03:09??? LOL You'll make it ALL NIGHT long again, eh, you clinically insane,
lonely, senile pest? LOL

--
Marland revealing the senile sociopath's pathology:
"You have mentioned Alexa in a couple of threads recently, it is not a real
woman you know even if it is the only thing with a Female name that stays
around around while you talk it to it.
Poor sad git who has to resort to Usenet and electronic devices for any
interaction as all real people run a mile to get away from from you boring
them to death."
MID:

On Friday, 6 December 2019 16:10:06 UTC, Rod Speed wrote:
tabbypurr wrote in message

If you're not short of headroom just use a 1 piece ladder with weight on a
pulley.

When using multisections the pulley mech doesn't need to balance it, just
needs to keep it within workable limits.

Havent seen too many roofs with that much room.

He did say its not at the peak of the roof.

I didn't know you had sight issues. So that's sight issues, brain issues, hearing issues, comprehension issues & sense issues. Anything else?

On 06/12/2019 16:07, wrote:
On Thursday, 5 December 2019 18:14:20 UTC, wrote:
On 05/12/2019 16:11, newshound wrote:
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.
Clearance isn't an issue; the hatch isn't at the centre of the span but
there's no shortage of space above it.
I've been looking at commercial mechanisms and spare parts, but mine
will be heavier (mostly because of the door and because I want to make
the steps as wide as possible). There seem to be lots of spring design
websites but I've no idea how to estimate the required spring force.
The answer might be to use off-the-peg bits and to keep adding springs
until the weight is roughly balanced, but the loads on the attachments
might get worrisome.
With all the other jobs in progress I'm not exactly wanting another, but
it's a problem that needs solving and it's useful to gather info.

If you're not short of headroom just use a 1 piece ladder with weight on a pulley.
That's an interesting idea. A 1-piece ladder mounted to the trapdoor on
some sort of rollers so the ladder pushes-up until the bottom clears the
edge of the door and latches in place, the top of the ladder then drops
down onto the attic floor as the door is closed. The trapdoor needs to
be hinged at ceiling level so, with 8" joists, the ladder would need to
be held at least 9" above the door to be able to lie flat on the floor.
At the moment I can't see how a pulley and counterweight could be made
to work when the top of the ladder would be swinging through a large
arc, but it might be possible to use a long spring, rope and pulley
between somewhere on the door and somewhere on the ladder.

When using multisections the pulley mech doesn't need to balance it, just needs to keep it within workable limits.


NT

On Friday, 6 December 2019 20:34:00 UTC, wrote:
On 06/12/2019 16:07, tabbypurr wrote:

If you're not short of headroom just use a 1 piece ladder with weight on a pulley.
That's an interesting idea. A 1-piece ladder mounted to the trapdoor on
some sort of rollers so the ladder pushes-up until the bottom clears the
edge of the door and latches in place, the top of the ladder then drops
down onto the attic floor as the door is closed. The trapdoor needs to
be hinged at ceiling level so, with 8" joists, the ladder would need to
be held at least 9" above the door to be able to lie flat on the floor.
At the moment I can't see how a pulley and counterweight could be made
to work when the top of the ladder would be swinging through a large
arc, but it might be possible to use a long spring, rope and pulley
between somewhere on the door and somewhere on the ladder.

When using multisections the pulley mech doesn't need to balance it, just needs to keep it within workable limits.


NT


I think you may be overthinking this counterweight thing. Mine has no counterweight or spring and is just fine. If you make one that's awkwardly heavy, a partial counterweight should be enough. A 1 storey ladder is not normally overly heavy.


NT

wrote in message
...
On Friday, 6 December 2019 16:10:06 UTC, Rod Speed wrote:
tabbypurr wrote in message

If you're not short of headroom just use a 1 piece ladder with weight
on a
pulley.

When using multisections the pulley mech doesn't need to balance it,
just
needs to keep it within workable limits.

Havent seen too many roofs with that much room.

He did say its not at the peak of the roof.

I didn't know you had sight issues. So that's sight issues, brain issues,
hearing issues, comprehension issues & sense issues. Anything else?

You never could bull**** your way out of a wet paper bag.

On Sat, 7 Dec 2019 10:10:23 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the clinically insane asshole's troll****

10:10??? LOL

NO sleep AT ALL for you abnormal clinically insane senile cretin? You've
been up and trolling ALL NIGHT LONG, yet again! LMAO

--
dennis@home to retarded senile Rot:
"sod off rod you don't have a clue about anything."
Message-ID:

On 06/12/2019 20:43, wrote:
On Friday, 6 December 2019 20:34:00 UTC, wrote:
On 06/12/2019 16:07, tabbypurr wrote:

If you're not short of headroom just use a 1 piece ladder with weight on a pulley.
That's an interesting idea. A 1-piece ladder mounted to the trapdoor on
some sort of rollers so the ladder pushes-up until the bottom clears the
edge of the door and latches in place, the top of the ladder then drops
down onto the attic floor as the door is closed. The trapdoor needs to
be hinged at ceiling level so, with 8" joists, the ladder would need to
be held at least 9" above the door to be able to lie flat on the floor.
At the moment I can't see how a pulley and counterweight could be made
to work when the top of the ladder would be swinging through a large
arc, but it might be possible to use a long spring, rope and pulley
between somewhere on the door and somewhere on the ladder.

When using multisections the pulley mech doesn't need to balance it, just needs to keep it within workable limits.


NT


I think you may be overthinking this counterweight thing. Mine has no counterweight or spring and is just fine. If you make one that's awkwardly heavy, a partial counterweight should be enough. A 1 storey ladder is not normally overly heavy.


NT

I can accept that for a regular ladder, but my thoughts have developed a
bit. I want more of a pull-down staircase than a regular ladder, with
treads instead of dowels, and also for the ladder to be wider than the
standard 400mm - maybe 550 wide. If a regular wooden ladder is about
10kg I'd guess I'd be heading more towards 25kg. When the ladder is in
the "up" position the top part should partly counterbalance the door and
ladder so all I need is a means of taking-out the rest of the load
(up'n'over garage door thingy?) and a means of reducing the effort of
sliding the ladder from the down to the up position. I also need a box
of tuits!

On Saturday, 7 December 2019 10:54:27 UTC, wrote:
On 06/12/2019 20:43, tabbypurr wrote:
On Friday, 6 December 2019 20:34:00 UTC, wrote:
On 06/12/2019 16:07, tabbypurr wrote:

When using multisections the pulley mech doesn't need to balance it, just needs to keep it within workable limits.


NT


I think you may be overthinking this counterweight thing. Mine has no counterweight or spring and is just fine. If you make one that's awkwardly heavy, a partial counterweight should be enough. A 1 storey ladder is not normally overly heavy.


NT

I can accept that for a regular ladder, but my thoughts have developed a
bit. I want more of a pull-down staircase than a regular ladder, with
treads instead of dowels, and also for the ladder to be wider than the
standard 400mm - maybe 550 wide. If a regular wooden ladder is about
10kg I'd guess I'd be heading more towards 25kg. When the ladder is in
the "up" position the top part should partly counterbalance the door and
ladder so all I need is a means of taking-out the rest of the load
(up'n'over garage door thingy?) and a means of reducing the effort of
sliding the ladder from the down to the up position. I also need a box
of tuits!

Well I tried.

On 07/12/2019 12:36, wrote:
On Saturday, 7 December 2019 10:54:27 UTC, wrote:
On 06/12/2019 20:43, tabbypurr wrote:
On Friday, 6 December 2019 20:34:00 UTC, wrote:
On 06/12/2019 16:07, tabbypurr wrote:

When using multisections the pulley mech doesn't need to balance it, just needs to keep it within workable limits.


NT


I think you may be overthinking this counterweight thing. Mine has no counterweight or spring and is just fine. If you make one that's awkwardly heavy, a partial counterweight should be enough. A 1 storey ladder is not normally overly heavy.


NT

I can accept that for a regular ladder, but my thoughts have developed a
bit. I want more of a pull-down staircase than a regular ladder, with
treads instead of dowels, and also for the ladder to be wider than the
standard 400mm - maybe 550 wide. If a regular wooden ladder is about
10kg I'd guess I'd be heading more towards 25kg. When the ladder is in
the "up" position the top part should partly counterbalance the door and
ladder so all I need is a means of taking-out the rest of the load
(up'n'over garage door thingy?) and a means of reducing the effort of
sliding the ladder from the down to the up position. I also need a box
of tuits!

Well I tried.

I'm grateful for making me realise that a one-piece sliding ladder could
be a better solution than a z-fold.

wrote in message
...
On Saturday, 7 December 2019 10:54:27 UTC, wrote:
On 06/12/2019 20:43, tabbypurr wrote:
On Friday, 6 December 2019 20:34:00 UTC, wrote:
On 06/12/2019 16:07, tabbypurr wrote:

When using multisections the pulley mech doesn't need to balance it,
just needs to keep it within workable limits.


NT


I think you may be overthinking this counterweight thing. Mine has no
counterweight or spring and is just fine. If you make one that's
awkwardly heavy, a partial counterweight should be enough. A 1 storey
ladder is not normally overly heavy.


NT

I can accept that for a regular ladder, but my thoughts have developed a
bit. I want more of a pull-down staircase than a regular ladder, with
treads instead of dowels, and also for the ladder to be wider than the
standard 400mm - maybe 550 wide. If a regular wooden ladder is about
10kg I'd guess I'd be heading more towards 25kg. When the ladder is in
the "up" position the top part should partly counterbalance the door and
ladder so all I need is a means of taking-out the rest of the load
(up'n'over garage door thingy?) and a means of reducing the effort of
sliding the ladder from the down to the up position. I also need a box
of tuits!

Well I tried.

You've always been very trying.

On Sun, 8 Dec 2019 04:09:08 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH senile asshole's troll****

04:09??? And you've been up and trolling for HOW long already this night,
you useless senile trolling asshole?

--
Website (from 2007) dedicated to the 85-year-old trolling senile
cretin from Oz:
https://www.pcreview.co.uk/threads/r...d-faq.2973853/