Mostly Printed Continuous Ropewalk - for Scale Ship Model Builders

A Slight Preface:

This has been a stretch to make a project like this in 2 weeks for the rope and string contest.

But I slid in, just in time!

I did have a head start though. 15 years ago, I was an avid ship model builder. I was a member of several online forums and made the acquaintance of a gentleman that was smarter than I ever will be. This is based on his design. Back then, I made a handful of these and tried to sell them, with his permission. They were complicated and tricky to work and I regret asking money for them.

Sadly, this brilliant man is no longer with us, but his ideas and machines survive. You see variants of this online Some major improvements as well. Some even are basically autonomous. But, they also cost $250+ and I don't know that the results are the same for every operator. This design is from the original and follows how he and I worked out the details. If something wears out, you can print a new part. If you don't find that you use it, you're out $45, but at least you made your own. And making your own is way better than buying one.

In an effort to make up for my failings 15 years ago, I offer this design to the world. It could use some tweaks and there is the possibility for automation with an Arduino genius, some tension sensors and maybe a counter, some sort of micro controller, a happy little tree here or maybe a mountain lives there?. I will leave that to those with better abilities than I. I have all the parts in .step files and will gladly share for the asking.

In the end, you cannot patent making rope. I mean, it's like saying you invented a 2x4, or Pizza toppings.

Rope

Rope making is ancient. Check out the Wiki https://en.wikipedia.org/wiki/Rope#Styles_of_rope... Ship building is also ancient and making ship models is almost as old. People spend endless hours making exact replicas of every aspect of these machines, down to the most delicate detail. Rope is one of these details. Cable laid, Hawser laid, 3-strand, 4-strand, Stay, on and on. and commercially available rope that looks like scale rope is expensive and hard to find.

SO without further adieu........

I introduce the Mostly Printed Continuous Ropewalk.

Continuous? Well, Everything has an end, so that is an exaggeration. This is limited to how much thread you can load onto a standard sewing machine bobbin. But, it's a lot. The typical Ropewalk, DIY, scale or real life full size version is limited to the length of the building or table top you are working with. This machine is 24 inches long and can easily produce 100+ feet of quality 3 strand rope. All for ~$45 if you have a printer, $150 if you have to pay someone to print the parts.

Why 3 Strand and not 4, well, even I am not that OCD and to the eye, at this scale, I cannot tell a 3 strand from a 4 strand. Plus, I had 2 weeks to design, print, build, test and write this up. So, if you want 4 strand, ask me for the .step files and I will send you a link. Just share it with the world and don't make any money from it.

That Said....

Let us begin.....

Hand Tools, a drill, drill bits, C-Clamp for pressing in the Skate Board Bearings, and means to cut a steel 8MM Shaft. You will also need Solder, Flux Pen, Soldering Iron, Heat Shrink Tubing, Means to shrink said tubing, and 4" zip ties.

Attached to this step is the BOM. It lists everything you need to be printed and hardware with links to specialty parts..

I try to design all 3-D printed parts to avoid supports, alas, I needed supports on the Gear Shaft, but I tried. All the rest are support free. List is in the BOM, Files are attached.

Print with PLA or PetG, 55% infill. Brims help but are not needed if you are having a good adhesion day.

Use 3 walls

Watch the extrusion on the gears. Too much and they will not mesh and too little, pfft, no one wants to talk about Under Extrusion.

~55 hours print time at 40mm per second. I print slow. You can really cut this down if you rev it up to 60mm.

I am also putting these on Thingiverse to Cross Pollinate this design. https://www.thingiverse.com/thing:4171364

Tip: Pre-Thread your Nyloc Nuts a couple of times before assembling. It will be easier on the plastic and help you avoid jamming a flat head screw driver in the slot to hold the nut for tightening.

You will notice in my pictures, the EMT Conduit is longer. That is because this is a prototype and from start to finish I spent 2 weeks on it. I wasn't sure if I would need more lead space after the head and before the spool to form the rope. As it stands, 24" is a good overall length. It probably could be shortened 2 or 3" but I did not have time at publishing to experiment more.

Nothing Fancy here. Cut the 8MM shaft with a 4" Grinder and a cut off wheel or a Hack Saw and a LOT of elbow grease. Or Porta-Band or whatever. Bevel the ends, make sure they are burr free and smooth to allow for easy assembly.

Look to the Head Assembly for pressing in the bearings.

I use Super Glue, Epoxy or Model Cement will work

Slow and Steady with the bearing press.

Go Ahead and slide one of the shaft collars on the main assembly. Leave it loose for now to allow for Head Positioning at the end. Then slide on one of the main body parts to the Main Shaft for Head assembly.

Put a Captive 3MM Nyloc in 19 - Main Gear, Slide the gear onto the main shaft. Install the (3) Spur Gears.

Lock down the Main Gear to the Main Shaft with a M3 x 16MM Cap Screw. If it does not lock down tight, you may need to file a flat on the shaft at this location to hold the gear in place and allow for the little bit of torque we need to overcome.

Read the notes in the picture.

Also, keep the Bobbin Holders (part 5) straight to the Spur Gear Shaft and parallel to the Main Body face. It will make the machine operate better and prevent vertigo watching catty-wampass bobbins flaying about.

If you are having trouble getting the bobbin holders to stay put, thread the holes in the spur gear shaft ends to M3 and use some M3 x 10 Button Head Cap screws to lock them down.

Just follow the comments in the photos

The handle assembly sits inside the square boss in the spool. Glue the spool halves together and secure with a M3x12 Socket Head Screw with a M3 Nyloc Nut. You may want to make several of these so you can store your scale rope. Maybe an Instructable on a rack to hold them can be made by someone??

Tip: When setting the Nyloc Nut, put it on a 2.5mm bit as in the picture and then insert it straight and true into the provided recess. This prevents going in crooked and jamming it up.

This is fairly simple to wire in. You will need a DPDT Mini Switch. DPDT = Double Pole, Double Throw. Meaning, you have 2 poles per switch positions, of which, there are 2.

The goal is to reverse the direction of the DC motor. Positive to Positive, Negative to Negative will make the motor run Forward. Positive to Negative, Negative to Positive will reverse its polarity and, in turn, reverse the rotation.

So, Solder your 24ga wire, about a 2' length, to the motor. Also, bring a 4' or so length to whatever 12v Wall Wart you are using or power supply. these will all land in the little control box.

Solder on the positive side of the power supply to the left center terminal on the switch, looking at it from the rear. Then repeat with the negative on the right.

At the ends of the wires for the motor, splice on 2 wires, ~4" or so.

Follow the diagram to solder on the motor supplies. Basically, one on one side above, the opposite side below.

Rotation is marked on the Control box. Just test it out and rotate the switch to match rotation.

I provided Zip Tie slots to chase the wires in the box. 21 Control Cover attaches to 20 Control with zip ties. Chase both the power in and motor feed back to the motor, zip tying as you go to keep it neat.

See the pictures for how I did it.

I like polyester thread. It has less fuzziness and it does not stretch as bad as cotton. The Downside is you cannot dye it. I ended up buying 3 spools of Taupe Upholstery Tread. 50 yds per spool. Most of it fit on the standard bobbin with a little room to spare.

Chuck one of the M5 x 25 in a cordless drill, place a bobbin on it and then use a M5 Nyloc to snug the bobbin down. Then tie an end of your tread around the Bobbin and wind it slowly at first and then fill up the spool. Make sure you have tension on the the thread so that the fill is solid. This prevents jamming later on.

Now, take note of the wind of your thread. if you twist it to the right and it tightens, you will need to run the machine head away from you. Opposite if it tightens to the left. Remember this in the next step.

Load the bobbins and put in the tension bolts.

Here is where practice will come into play. Imagine pulling a shoe lace untied. This is the range of tension you want on these. and , they all need to be as equal as possible. I suppose a pull scale would be of benefit here. Just get it as close as you can. we have remedies for unequal tension later on after the rope is formed. Because for the first few uses, there is sufficient tension in the holder itself, just secure the cap screw and nut so that the bobbin has an axle.

Thread each strand through it's corresponding eye and through the 16 - Winder, tie these into a square not and twist and pull until you can reach your spool with enough slack to form a loop and cinch it around the spool.

It should look like the photo.

Find a comfortable place.

If you are left handed, hopefully you built this backwards. It is a simple matter of reversing the 6 - Clamps and 20 - Control side.

Remember the twist direction of your thread.

Grasp the outer main body of the head.

Flip the switch to coordinate with the thread twist.

Allow the gears to twist the individual threads for a few seconds. once you see them tighten and thread being pulled from the bobbins, begin to turn the spool handle clockwise while at the same time releasing some of the grip on the main head. Watch the rope "Lay" together right after the right side of the winder. If you see loose spots, grip the Head tighter, if you see knotty places, spin the spool a little faster.

In a few minutes, you will Zen out into a happy place of rope making. Keep on keeping on until your bobbins are empty.

Twist a little, Lay a little, Pull a little, rinse and repeat.

You need to lock down the final tails with a dab of glue or a knot.

Cut them free from the machine and remove the spool.

See the Video, Don't laugh too hard!! But it explains things better than I can write them

This is a home made machine making home made rope. And we are humans. There will be unequal tension through out the rope.

Grab you kid or spouse or friend and and have them help you unwind the rope from the spool. Don't let the rope just "go", you will end up with a knotted mess. Simply pull the rope off the spool and let it pass through pinched fingers. The rope will spin to continue to lay the rope. It will spin a lot. Let it spin until it does not spin anymore, but control the spin. Think a 1952 Bait Casting reel on a windy day birds nest type of thing, It will equal out and you will have a nice scale rope.

The photos show the rope made on the machine from 3 strands of Upholstery Thread. The next step is were this machine really shines.

Now, let's use this rope and make a larger rope.

Wrap the 3 bobbins back to 3/4 full. make sure you dab a small amount of superglue on the ends. It will prevent it from unraveling and it also serves as a "needle" to thread the machine. Just cut them on an angle at the super glue location,

Reload the machine and Operate it in the same manner, except reversing the motor.

Tip: To save your good rope, put a leader on the spool to the 3 strands coming off the Head. You will prevent 6 or so inches of scrap.

Equalize the tension and viola, you have a beautiful scale rope.

The final picture shows the results of a 9 strand rope made on this machine.

Well, there you have it. This doesn't take a team of people dressed in Medieval Garb to make. In Fact, on a quiet Sunday afternoon, you can make a couple hundred feet of good quality scale rope, alone, in the peace and solitude of your workshop.

If you continue to use this, you can increase the speed of the gear motor to 50 or 60 RPM. 15 RPM is a good training speed though.

Download it, build it and make it your own. Just share it.

If you have made it this far, you must know how to properly pronounce Gunwale and Forecastle and Quay and Boatswain. If you post a picture of a ship model you are making or have made, I will pick a winner and send this machine to you, free of charge. I do not build ship models any longer, so this machine will sit on the isle of misfit toys until I decide to chuck it out. Deadline is 4/5/20.

Salute Mr. Jim