captain_spalding said:

can’t be done. not enough information.

ChrispenEvan said:

captain_spalding said:

can’t be done. not enough information.

Yes, you might want some content with that.

Working on that now. Apologies.

ChrispenEvan said:

captain_spalding said:

can’t be done. not enough information.

LOLOL

The answer is 4.

captain_spalding said:

Ok, you might want some content with that.

I have made a rope-making machine, as per a short series of videos from this source:

https://www.youtube.com/watch?v=RM9GY-n6PEA&t=6s

and it works wonderfully, just as described in the videos. It produces cordage of uniform ‘lay’ (twist)’ from any old twine that you care to thread it with.

I put some simple, cheap cotton twine on it, and it laid the twine up into a uniform three-strand cord, tightly twisted and very pleasing to the eye. It’s the kind of cordage that i’ve sought for literally years for ropework projects, but which is, as far as i can ascertain, utterly unobtainable in this country, and in most other places.

The only problem is that the mechanism relies on a simple deadweight (in this case, a platic bottle filled with water) hanging at the end of a cord to provide the necessary constant tension against which the twisting mechanism ‘pulls’ so as to impart the right tension to the lay of the cordage.

This is a limiting factor, as, once the deadweight is drawn up hard against the ‘bottom end’ of the machine, then that’s it, that’s as long a length of cordage as you can produce on that run.

I can conceive that, to produce longer lengths of cordage, a reel of cord might provide the same counterweighting effect as the bottle of water, and that it would permit far longer runs of the machine, so that longer lengths can be made.

But, i’m not smart enough to work out if just a reel of cord would do the job.

I might, for example, weight the reel so that it has a mass of, say, 3kg, and thus exerts a ‘resistance’ of 3kg. Certainly, that would be the case at the start of the run.

But, would that mass/resistance alter during the course of the run? As the line pays out from the reel, does the resistance to the pull exerted by other parts of the mechanism alter, possibly becomiong less and less?

Or, is it the case that the 3kg mass/resistance remains in the system, whether the line is wound on the reel, or paid out in a long straight line?

Just run the rope/string through a gadget that makes a bit of friction on it, so there’s always tension going into the mechanism.
Something as simple as having the spool of rope/thread on a roller with a brick leaning on it, to slow it down.

Spiny Norman said:

Just run the rope/string through a gadget that makes a bit of friction on it, so there’s always tension going into the mechanism.
Something as simple as having the spool of rope/thread on a roller with a brick leaning on it, to slow it down.

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

captain_spalding said:

Spiny Norman said:

Just run the rope/string through a gadget that makes a bit of friction on it, so there’s always tension going into the mechanism.
Something as simple as having the spool of rope/thread on a roller with a brick leaning on it, to slow it down.

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

Can you not extend the counterweight cord up and over a pulley handing from the ceiling, say, or garage roof (depending on where you are set up), so that you could have the same weight but (a lot) more distance for it to cover before it reaches the ‘stop’?

AussieDJ said:

captain_spalding said:

Spiny Norman said:

Just run the rope/string through a gadget that makes a bit of friction on it, so there’s always tension going into the mechanism.
Something as simple as having the spool of rope/thread on a roller with a brick leaning on it, to slow it down.

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

Can you not extend the counterweight cord up and over a pulley handing from the ceiling, say, or garage roof (depending on where you are set up), so that you could have the same weight but (a lot) more distance for it to cover before it reaches the ‘stop’?

“handing” = hanging

AussieDJ said:

AussieDJ said:

captain_spalding said:

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

Can you not extend the counterweight cord up and over a pulley handing from the ceiling, say, or garage roof (depending on where you are set up), so that you could have the same weight but (a lot) more distance for it to cover before it reaches the ‘stop’?

“handing” = hanging

Thanks, DJ. That’s precisely the solution i came up with myself, as something of an interim measure. Great minds think alike, eh? But, again, it produces relatively short lengths of cordage, although rather longer than those made by the initial set-up.

If the reel-counterweight solution can be made to work, i might be able to make lengths of 20 metres or so.

captain_spalding said:

Spiny Norman said:

Just run the rope/string through a gadget that makes a bit of friction on it, so there’s always tension going into the mechanism.
Something as simple as having the spool of rope/thread on a roller with a brick leaning on it, to slow it down.

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

Okay have the rope/thread spool on its own roller with zero friction.
Run the rope/thread parallel to the floor, to another drum/roller and wrap the rope/thread around it several times so it’s got a good grip on the drum/roller. Use a simple friction mechanism on that drum/roller and then it won’t matter how much is left on the main spool.

Spiny Norman said:

captain_spalding said:

Spiny Norman said:

Just run the rope/string through a gadget that makes a bit of friction on it, so there’s always tension going into the mechanism.
Something as simple as having the spool of rope/thread on a roller with a brick leaning on it, to slow it down.

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

Okay have the rope/thread spool on its own roller with zero friction.
Run the rope/thread parallel to the floor, to another drum/roller and wrap the rope/thread around it several times so it’s got a good grip on the drum/roller. Use a simple friction mechanism on that drum/roller and then it won’t matter how much is left on the main spool.

Thanks, Bill. A rather elegant solution that would have never occurred to me. I had thought of some kind of tensioning pulley, but was pondering on its likely effect (or lack of it), and just how to achieve the desired result.

I was sure that one of the group of Forumites who have a background in sciences and mechanics etc. would be able to shine the light of ingenuity on it, and i’ve been proven right.

I’ll tinker with the device, and introduce modifications one step at a time, to observe their effects.

captain_spalding said:

Spiny Norman said:

captain_spalding said:

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

Okay have the rope/thread spool on its own roller with zero friction.
Run the rope/thread parallel to the floor, to another drum/roller and wrap the rope/thread around it several times so it’s got a good grip on the drum/roller. Use a simple friction mechanism on that drum/roller and then it won’t matter how much is left on the main spool.

Thanks, Bill. A rather elegant solution that would have never occurred to me. I had thought of some kind of tensioning pulley, but was pondering on its likely effect (or lack of it), and just how to achieve the desired result.

I was sure that one of the group of Forumites who have a background in sciences and mechanics etc. would be able to shine the light of ingenuity on it, and i’ve been proven right.

I’ll tinker with the device, and introduce modifications one step at a time, to observe their effects.

Cool.
FWIW I 3D printed a fillament spool holder for my printer a few years back. To help keep a bit of tension on the filament – as it tends to SPROING! itself out of the spool when new – it’s got a variable friction mechanism on the side.
And of course I can’t find the model online sorry. Something like that would work for you quite well I would think.

Spiny Norman said:

captain_spalding said:

Spiny Norman said:

Just run the rope/string through a gadget that makes a bit of friction on it, so there’s always tension going into the mechanism.
Something as simple as having the spool of rope/thread on a roller with a brick leaning on it, to slow it down.

Thganks, for that, Bill. An interesting idea, and i can see how it’d work.

But, my aim is to have a steady and unchanging degree of tension/resistance on the ‘counterweight’ line, so as to eliminate any variation in the twist imparted to the cordage being produced. Don’t want one part of it wound tighter than another part.

If there’s any loss of ‘resistance’ inherent in the unwinding of the reel of counter-acting cord, then that variation will still be present, even if i apply a source of friction to the reel.

Actually, my own amateurish estimation is that there’ll be no change in the resistance as the reel unwinds, as the component parts will remain the same, and so their mass (resistance) will be unchanged.

There’s a couple of ‘experiments’ with the workings of this device that have sprung to mind. This question of the ‘reel counterweight’ may just be another experinment to be done. Unless a Forumite can clear it up for me.

Okay have the rope/thread spool on its own roller with zero friction.
Run the rope/thread parallel to the floor, to another drum/roller and wrap the rope/thread around it several times so it’s got a good grip on the drum/roller. Use a simple friction mechanism on that drum/roller and then it won’t matter how much is left on the main spool.

Sounds like threading up a sewing machine.

Spiny Norman said:

captain_spalding said:

Spiny Norman said:

Okay have the rope/thread spool on its own roller with zero friction.
Run the rope/thread parallel to the floor, to another drum/roller and wrap the rope/thread around it several times so it’s got a good grip on the drum/roller. Use a simple friction mechanism on that drum/roller and then it won’t matter how much is left on the main spool.

Thanks, Bill. A rather elegant solution that would have never occurred to me. I had thought of some kind of tensioning pulley, but was pondering on its likely effect (or lack of it), and just how to achieve the desired result.

I was sure that one of the group of Forumites who have a background in sciences and mechanics etc. would be able to shine the light of ingenuity on it, and i’ve been proven right.

I’ll tinker with the device, and introduce modifications one step at a time, to observe their effects.

Cool.
FWIW I 3D printed a fillament spool holder for my printer a few years back. To help keep a bit of tension on the filament – as it tends to SPROING! itself out of the spool when new – it’s got a variable friction mechanism on the side.
And of course I can’t find the model online sorry. Something like that would work for you quite well I would think.

Found it, but for some reason I can’t link directly to it. Anyway there’s a few mechanisms here that could do it.
https://www.thingiverse.com/search?q=Universal+Auto-Rewind+Spool+Holder&page=1

Spiny Norman said:

Spiny Norman said:

captain_spalding said:

Thanks, Bill. A rather elegant solution that would have never occurred to me. I had thought of some kind of tensioning pulley, but was pondering on its likely effect (or lack of it), and just how to achieve the desired result.

I was sure that one of the group of Forumites who have a background in sciences and mechanics etc. would be able to shine the light of ingenuity on it, and i’ve been proven right.

I’ll tinker with the device, and introduce modifications one step at a time, to observe their effects.

Cool.
FWIW I 3D printed a fillament spool holder for my printer a few years back. To help keep a bit of tension on the filament – as it tends to SPROING! itself out of the spool when new – it’s got a variable friction mechanism on the side.
And of course I can’t find the model online sorry. Something like that would work for you quite well I would think.

Found it, but for some reason I can’t link directly to it. Anyway there’s a few mechanisms here that could do it.
https://www.thingiverse.com/search?q=Universal+Auto-Rewind+Spool+Holder&page=1

Thanks, Bill, and yes, buffy, it does remind me of a sewing machine. Perhaps i should look to Mrs S’s sewing machines for inspiration, too.