Making a Unique Ruling Pen

[secret_squirrel]

Greetings all,

 

I found a pen on a Youtube video that I am very interested in. 

https://www.youtube.com/watch?v=nYRJg0nO6UY

The video cites the pen's creator as none other than Dipper on this very website (which is what led me here to begin with)

The pen is a variant of a "Ruler" style pen that Dipper created to be used with multiple different inks and paints, while being easy to clean. I fell in love with this design at first sight. I searched around for a while and was unable to find any nib similar to this, so I reached out to Dipper here on the forum. He was happy to help, but he isn't able to sell them as they are one-offs and were more of a project for him. So I set my mind on picking his brain to see how he created them in hopes that I could make one myself. Dipper suggested that I made a post here so that the community could both contribute to and benefit from the discussion which I thought was a great idea.

So if anyone (including Dipper himself) has any advice, ideas, or improvements please let me know!

Please share how you would go about creating this pen as well as any improvements you would make.

 

I am quite fond of the shape of the nib. I like the solid metal square design, and the line variation that can be achieved with it.

I've attached some screenshots of the pen from Peter's Youtube video of it (linked above).

What I know so far:
The nib is made from a 10mm square 316 grade stainless steel bar

 

 

What I want to know:

Estimated cost?

Would other materials work?

What are the dimensions?

How to cut the tapered slit that widens towards the reservoir?

[dipper]

Here is the original image. It is a bit sharper than the screen grab from the Peter Draws video.

 

Estimated cost:

A lot of sweat, frustration and damaged fingertips. The cash cost depends on materials chosen.

 

At top of photograph is a purchased ArtCoe ruling pen. Tip reshaped. It works, but has low ink capacity and is fiddly to hold and use. Cost about £4 UK.

 

In the body of the photograph from left to right:

 

A big fat brass woodscrew in a bamboo tube. Cost a few pence.

 

An Easton target archery arrow point, mounted in aluminium arrow shaft. Cost - just scraps I had lying around.

 

Pens 1 & 2 & 5. An unknown piece of steel rod from my scrap store. They are showing slight corrision now. Cost zero.

 

Pens 3 & 4. Each made from a five inch galvanised mild steel nail. Pen 3 is a short stub mounted in a handle. Despite the zinc galvanizing being removed at the working end of the pens, and of course in the ink slot, these show no corrosion, nearly a year after making. Cost a few pence.

 

Pens 6-12 and 15 (pen ten is missing from the family photograph because it went off to Peter in USA for his video). 316 grade stainless steel 10mm sq bar. Cost something less than £2 per pen, bought in 250mm cut lengths. These probably cost more per pen for hacksaw blades and abrasives than for the steel!

https://www.metals4u.co.uk/materials/stainless-steel/stainless-steel-square/13535-p

 

Pens 13 & 14. Phosphor Bronze rod 1/2 inch diam. Cost about £4 per pen. MUCH easier to work than 316 stainless.

https://maccmodels.co.uk/shop/1-2-12-7mm-dia-phosphor-bronze-pb102-12-2/

 

And other materials? I have tried wood, and bone. They do work, but only for really big tips that make line widths of a few mm. Wood is very easy to work of course compared with metal. I have a large artwork done entirely in acrylic paints applied with wooden ruling pens that I made.

 

Cutting the slot:

Hacksaw! A "high tension" hacksaw frame proved to be an excellent investment.

Then layers of abrasive paper pulled through the slot to smooth the inside. Done by hand for the first few pens, then later I upgraded to spinning disks - two sheets back to back - mounted in an electric drill.

 

Slot dimensions:

After working a flat parallel sided slot the two tines are bent inwards to almost touching. Then the tip is shaped.

 

Will need to look back through my workshop notes for dimensions. (And this is the really interesting part where the mysteries of surface tension play a big part.) Will be back soon with another post about dimensions.

[secret_squirrel]

Oh wow. Why did I not think of bending them? That seems so obvious now. Thank you for the information! This definitely gives me a place to start! I look forward to reading anything else you have.

 

[MarkDC42]

Hi Dipper, would it be possible to buy a pen like number 8? And a bronze tip like in pen 13 and 14 as well? As much as making my own dip pen intrigues me, I just don't have the time but seeing your pen at work in Peter's video was pretty amazing.

 

All the best.

 

Yours,

Mark

[dipper]

.....Would it be possible to buy?

 

My pens are not for sale, sorry about that.

 

Would it be possible for a manufacturer to make these for sale? .... Yes certainly !!!!

 

Many manufacturers currently make the traditional "ruling pen" design, sold for just a few pounds. They appear to be copies of the same ancient design. And they don't work well enough to be really effective drawing or painting or writing tools..... 

 

The only reason my pens work better is that the dimensions and angles and curves are altered slightly from the ancient design. But those small changes make a huge difference to how inks and paints behave in the pens.

 

I have not fully solved the design of the dimensions and angles though. Some of my pens don't work very well - and I don't know why!

 

Perhaps together, on this forum, we can solve the design problems?

And perhaps a manufacturer can then make the pens that a number of us want to buy.

That could be a factory made product, or it could be one person running a small craft business.

 

There are others trying to make similar improvements:

https://scribblers.co.uk/product/set-of-6-dreaming-dogs-ruling-pens-in-a-case/

You can find demos of how those pens perform on YouTube.

 

 

 

[dipper]

I now have some ruling pen measurements ready to post in this thread. First though, I had a rethink of what would be best advice for anyone who wants to try their hand at making an improved ruling pen.

 

In 2020 I  did not jump straight in making Peter Draw's steel pen, or the other metal pens shown so far. By 2020 I already had plenty of practise making wooden ruling pens, using just basic DIY hand tools.

 

So my revised advice is this:

If you have some basic craft skills, but only simple tools, try making some pens in wood first. All the metal pen dimensions (coming soon) should work for wood pens also, except for the tips of the tines. Wood pens will wear down unduly rapidly if the tips are too narrow.

 

On the other hand, if you have access to a proper machine shop then going directly into making metal pens should be no problem. (Easy machining metals would be a wiser start than 316 stainless!)

 

Another option that fascinates me is the possible use of 3D printing. Either printing directly in metal, or printing in plastic and then making a metal casting using a version of the lost-wax process.

 

But back in the world of wood..... What drawing can you do with a wooden ruling pen?

Here is a painting, or maybe it is a "paint drawing", that I made some years ago. Golden Fluid Acrylics & Liquitex Medium Body Acrylics,

all applied with wooden ruling pens, plus a few touches with steel dip pens for the very narrowest lines.

Canvas size is 760mm square.

Subject is "The Great Fire Of London", seen from inside the viewing platform at the top of "The Monument" column. 

 

https://www.themonument.org.uk/

 

Next up ... the wooden ruling pens.

 

[dipper]

Here is a simple wooden ruling pen that anyone with DIY skills can make. (Pencil included for size comparison.) This is not a great pen! But it does work, and the experience gained in making it will be invaluable.

 

 

Looking down into the ink slot:

 

And looking at the pen blade profile:

 

Method:

1) If you are in the UK, take two ice-lolly sticks.

If you are in the US, take two popsicle sticks.

 

2) Using penknife or craft knife, carefully and slowly carve out a hollow near to the tip of one (or both) sticks. See photo "into the ink slot" above for the general form, or if you want to be precise see "pen dimensions" in a future post of mine. Do not carve all the way to the end of the stick(s). (Later you will carve backwards  to meet the hollow.)

To save cutting your fingers it helps if you can clamp the stick to something large and heavy before you start carving. 

 

3) Cut a strip of thin card to match the width of the sticks. The length of the card is to run from the back end of the sticks to just short of your carved hollow.

 

4) Glue the sticks and card together as a sandwich with the sticks on the outside, carved hollow(s) facing inwards, and the card strip at the centre of the sandwich. Do not get any glue in the carved hollow. Clamp your sandwich flat until the glue has set hard.

 

5) Using penknife or craft knife, carve away the excess wood at the unglued tip of the pen, like sharpening a pencil, working backwards until you reach the hollowed out area and you see a little gap appearing at the pen point. Smooth and shape your wooden "nib tip" with fine sandpaper or a nail file.

 

6) Dip your pen into ink or paint and try writing or drawing with it.

 

Problems with this design are:

- Ink creeps up the pen onto your fingers.

- After a time the ink or paint soaks into the thin poor quality wood, the blades warp, and the pen stops working. (My pen returns to its original shape when allowed to dry out.)

 

Good things about this design are:

- It takes only minutes to make - plus a wait for the glue to set.

- It costs nothing.

- You can easily make more improved pens, with the same basic idea, better materials, a proper handle, or whatever other improvements you like.

 

My other wooden pens need a bit more effort and time to make. They are made from hardwood sticks, often donated by my wife from prunings of Viburnum, Forsythia, Lillac, Cornus, etc. See the next post ......

[dipper]

Here are photos of the wooden ruling pens that I do use as serious drawing and painting tools. I will not go into any how-to-make details for these. Hopefully the photos will be enough.

 

Some of these are the pens that were used to draw/paint "The Great Fire Of London" picture posted earlier. Over the years their tips have worn down and been resharpened a few times since then.

Some have gap adjusting screws. Some are glued with a wood shim, or bound with cord, holding the blades at a fixed ink reservoir angle.

Most show the shiny black residues of one of my favourite media: W&N waterproof black drawing ink.

 

One has been seriously re-carved to be a broad italic! About 5mm line width I think.

 

All these pens work well for medium to large size drawings and paintings.

The reason they all work is that if any pen is showing a problem it gets recarved outside, or reshaped in the slot with sandpaper, until it IS working!

( In other words - trial and error.)

 

Downsides are:

- The wood tips wear down.

- Even the thick hardwood can warp sometimes, needing readjustment work.

- The pen tips need a lot of drag force to move them over a painting surface.

- Fat rounded tips can last a long time (years), but narrow pointed tips wear away rapidly.

 

All those downsides are reasons for making metal ruling pens. Metal pens are hard wearing, low friction drag, can be made with very narrow tips, do not warp, and can be cleaned with stuff that would damage their wooden cousins (bleach, boiling water, etc).

We can't be making metal pens by random trial and error though!

Proper dimensions are needed.

.... cue the next post.

[dipper]

The ink slot in a ruling pen must narrow towards the tip. If the slot does not become narrower (blade to blade distance) then the blob of ink will be held back, up inside the slot, by surface tension effects, and the pen will not write.

 

Some pens may have one ink reservoir angle, as top sketch above, that is a roughly constant angle. Most ruling pens have a steeper angle towards the tip.

 

ArtCoe ruling pen (purchased):

The ink reservoir angle is 7 degrees over the distance between 5.2mm from tip to 1.6mm from tip. From 1.6mm down to the tip the reservoir angle is almost 11 degrees.

The blades are in fact formed as a continuous smooth concave curve, my measurements are average values over the distances stated.

These are very steep angles! The result is that the pen is guaranteed to always write, but wetness is difficult to control and the pen draws up little ink or paint at each dip. (3 or 4mm of ink say.)

 

My "improved" pens:

All 15 pens are slightly different! Their main ink reservoir angles are all in the range 0.42 degrees to 4.18 degrees.

Generally they have steeper angles at tips, and all are in the range 2.02 degrees to 5.72 degrees at their tips.

Lengths of the steeper portions are all in the range 1.83mm to 5.2mm.

 

Pen #10 (The Peter Draws pen):

Main reservoir angle = 1.34 degrees.

Steeper tip angle = 5.53 degrees.

Steeper tip length = 2.1 mm

 

The Pen #10 Ink Reservoir Angles are a good target to aim for.

 

The behaviour of the blob of ink or paint in the pen depends on other dimensions also though, interacting with the Ink Reservoir Angle(s).

Cue the next post....

 

[dipper]

 

Three dimensions in this post, as labelled in the sketch above. The sketch shows two views of the same pen, one looking through the slot and one looking face-on at the blades.

 

----------------------------------

Slot length:

 

Needs to be long enough so that dipping, and the ink rising up into the pen at each dip, does not take ink all the way to the back or "root" of the slot.

 

My 15 pens need just a couple of mm of tip dipped into ink or paint, and the pens will suck-up a column of ink over 5mm in length. My record so far is a 12.5mm drawn up! This varies greatly with the ink or paint type used.

 

My 15 pens slot lengths are all in the range 14mm to 25mm.

Pen #10 (the Peter Draws pen) is about 17mm slot length.

These lengths are kept relatively short because I am designing for stiffness and stability down at the tip end.

 

ArtCoe ruling pen: This has a much longer slot. Not because the ink will be drawn up that far, but to give elastic springy blades, an adjustable tip gap, and to lift the adjustment screw safely above any ink dips. Total slot length is 37mm. The downside of this feature is that the tips can flex sideways slightly, relative to each other, when drawing a curved line, amplifying scratchyness. (Tip form is a topic for a later post.)

 

----------------------------------

Pen Body Thickness:

 

The behaviour of the ink blob held in the pen is not affected by body thickness. This dimension is a matter or blade strength and stiffness.

The ArtCoe ruling pen's springy blades are about 1mm thick, with a total body thickness of 4mm to 5mm.

My 15 pens generally have blades at least 2.5mm thick at the blade root, and total body thickness around 8mm to 9mm. That range gives excellent stability at the tips.

A few of my pens are slimmer, because the fattest brass screw I could find was only 5mm shank diameter, or because I messed up when hacksawing and filing to shape! Those pens do suffer from slightly unstable tips due to my errors.

 

----------------------------------

Blade profile width:

 

This dimension is critical to the behaviour of ink in the pen. There is a lot here that I do not understand fully from the point of view of physics and surface tension effects.

Some changes made gave unexpected results. Sometimes when testing and modifying pens during manufacture the process does seem more like casting magic spells than science. (Magic = Science we have not figured out yet!)

 

I have done experiments watching blobs of water moving around between two glass microscope slides, separated by shims to various angles and overlapped to simulate different blade profile widths..... and all that I have come away with is fascination and a lot of guesswork.

 

Here are a few pointers that may contain some truth:

 

- A wider blade profile width gives a greater volume of ink drawn up into the pen, for a given ink column distance drawn up from the tip. (GOOD)

 

- My pens are in the range 7mm to 9mm Blade Profile Width, except for two made from nails at 5mm profile width and one made from a brass screw at 4mm profile width.

 

- The ArtCoe ruling pen Blade Profile Width is about 4.5mm. However, due to its steep Ink Reservoir Angle the maximum length of ink column held in the pen is around 5mm to 6mm long, and at that distance from the tip the (tapered) blade profile width is only 3mm. So the pen's functional blade profile width is 3mm.

 

- A wider blade profile width may be one cause of a problem I encounter occasionaly. Sometimes there is plenty of ink in the ink reservoir slot, but the ink is held back from the tip of the pen, and the pen stops working. If the ink is held back from the tip by 2mm or by just 0.2mm the result is the same - the pen stops writing - despite being full of ink! (BAD!)

 

- The Pen#10 (Peter Draws pen), and a few others with broader tips than pen #10, are in the 7mm to 9mm blade profile width range and they do not show any signs of the problem I have named "Tip Draw Back". They happily suck up loads of ink when dipped, and lay it down on the paper perfectly! (SO THAT IS "GOOD", BUT DOES NOT HELP US ARRIVE AT A TROUBLE-FREE RELIABLE DESIGN!)

 

.... more research is needed on the subject of Blade Profile Width.

 

 

Further ruling pen dimensions coming soon in future posts.

 

[Grayspoole]

Dipper—

 

Thanks for posting all of these details about your exploration of custom ruling pens. This all sounds like a lot of fun.

 

You stated, 

 

Another option that fascinates me is the possible use of 3D printing. Either printing directly in metal, or printing in plastic and then making a metal casting using a version of the lost-wax process.

 

I would warmly encourage you to investigate this route. I immediately thought of this when you first posted about your process and the difficulties you faced in shaping the metal rods by conventional means. You could use a company such as Shapeways (www.shapeways.com) that can produce items in stainless steel and other materials to your specifications. I have purchased sterling silver jewelry made by artisans using Shapeways. You would need to generate 3D digital shop drawings in a program such as Illustrator or Rhino—either by yourself or by using Shapeways’ design services, or by finding an impecunious design student who could do it for you.

 

Whatever you decide to do, keep us posted! You’ve inspired me to try some ruling pen calligraphy.  Paul Antonio has a video tutorial on making such a a pen from a soda can...

 

 

[dipper]

Folded soda-can dip pens are a lot of fun. As Paul Antonio says in the video above, ".... it's going to splatter!"

 

Looking at all the options for ruling-pen designs I see a spectrum of characteristics:

 

VERY FLEXIBLE BLADES

.... soda-can blades or similar

.... very scratchy

.... very splattery

SLIGHTLY FLEXIBLE BLADES

.... screw adjust ruling pens

.... a bit scratchy

.... good for ruling straight lines

 RIGID BLADES

.... the Peter Draws pen #10

.... tip can be made non-scratchy

.... gives cursive non-splattery lines.

 

One performance feature shared by all ruling pens, anywhere on the flexible-to-rigid spectrum, is that a curved edge profile allows line width adjustments by raising or lowering the angle between the pen axis and the paper. You can see that same performance feature being used in both the Peter Draws video (Rigid) and the Paul Antonio video (Flexible).

 

[dipper]

More of my ruling pen dimensions....

 

Here's a good tip:

The idea of this sketch is to show that the outer surfaces of the two blades of the pen, at the working tip, are both parts of a single smooth continuous surface. That surface  can be imagined arcing over the the gap between the two blades as a unified smooth dome.

At the "inner corners", as labelled in the sketch, you can imagine a crisp 90 degree corner between the outer curved surface and the inner plane faces of the slot.

 

Such a form is surprisingly easy to make. The blades are stiff and rigid in normal use, but during manufacture can be deformed inwards by crushing in a metalwork vice or by hammering on an anvil at the blade root area. This is done when the blades are still rough and knarly on the outside from hacksaw shaping work.

Crushing and hammering continues until the blades are permanently set to the designed ink reservoir angle and the tips are sitting at slightly closer than the intended tip gap.

 

Then the outer faces of the tips are rounded and smoothed with files and abrasive papers. Gradually working through finer and finer grades of abrasive I eventually reach 8000 grit micromesh.

During that rounding process the entire tip gets shortened lengthwise, perhaps by 2mm or so. As the tip is shortened the exposed tip gap gets larger. I monitor the tip gap with feeler gauges so I know when to stop.

(Tip gap size is a future post in this thread.)

 

The pen blades remain rigidly in position throughout that shaping process. You simply round off and polish the overall tip, almost ignoring the fact that there is an empty space between the two blades, and the continuous curved outer surface described above is automatically created.

 

Almost done.... but those crisp 90 degree inner corners need to be slightly rounded-off or else the pen will feel scratchy when in use. The rounding must be very slight, or the pen will refuse to write - the same as a fountain pen with "baby-bottom" nib problems.

I do the inner-corner-rounding with the same care that is shown when tuning a fountain pen nib, but use a different technique. A strip of very fine cotton fabric is pulled through the tip gap, pulled to turn a sharp corner at the tip inner edges. The fabric is moistened with metal polish. ("Peek" works well).

Three or four strokes, and then I test the feel of the tip on paper. Then a few more strokes, and test again. As soon as the scratchiness fades away I stop.

 

This usually takes ten to twenty strokes on each blade tip corner, with 316 Stainless Steel.

The improvement in pen smoothness is dramatic. However, under a 10x hand lens the corner rounding is just about invisible.

 

What size is the domed tip?

That depends which way you look at it:

 

(The dotted circles above are imaginary of course.) 

One circle matches the shape of the pen tip, viewed through the slot, for some arc length at the tip.

Another circle, that may be a different diameter, matches the pen tip arc when the pen is turned 90 degrees to look at the blade profile.

 

My 15 metal ruling pens have tip diameters ranging from 0.5mm up to 3.7mm.

 

Pen #10 (the Peter Draws pen) has a tip diameter of 0.9mm viewing through the slot, and 0.5mm when viewed looking at the blade profile shape.

 

The ArtCoe purchased ruling pen I have reshaped and polished slightly. Its current tip diameters are 2.2mm viewed through the slot and 1.2mm viewing the blades profile.

 

Measuring tip arc diameters?

I do that by eye and a 10x hand lens, comparing the pen tip to holes of known diameter in a thin metal sheet.

 

 

[dipper]

Continuing these pen dimensions, here in the area behind the rounded tip.

 

This area is the curve behind the small rounded tip.

Viewed in profile, as sketch above, we are looking edge-on at the part of the pen surface that makes broader marks when the pen is held at a lower angle  to the paper.

The dotted line marks the position of the back of the ink reservoir slot.

 

I have measured the included angle between the top and bottom faces of my pens at the position where the metal curve breaks away from the imaginary circular tip arc, and measured the angle again at a distance 5mm back from the pen tip.

 

My 15 pens have angles in the range 38deg to 65deg at the tip arc breakaway position, and 21deg to 46deg at 5mm back from the pen tip.

 

Pen #10 (the Peter Draws pen) has a tip arc breakaway angle of 52deg, and 43deg at 5mm back from tip.

 

The purchased ArtCoe ruling pen has a tip arc breakaway angle of 75deg, and 17deg at 5mm back from tip.

 

Here are the curves as worked from a solid bar of metal:

The outer grey rectangle is the original metal rod or bar.

The jagged light shape is the result of hacksaw cutting, and surface damage caused by hammering in the area at the blade roots to bend the blades inwards.

The inner dark grey shape is the final result after filing, grinding and polishing.

 

[dipper]

And now the important tip gap sizes:

 

My 15 pens have tip gap sizes in the range 0.125mm to 0.486mm.

 

Pen #10 (Peter Draws) has a tip gap of 0.196mm

 

The purchased ArtCoe ruluing pen has an adjustable gap. Typically I use it set to about 0.25mm.

 

I don't directly measure the tip gaps to the ridiculous accuracy quoted above.

Using Pen #10 as an example, these are the actual measurements taken:

A 0.2mm feeler gauge is inserted through the slot and moved towards the tip until it gets stuck. The feeler gauge is stuck at 0.04mm back from the tip, measured by digital callipers.

 

And a 0.40mm feeler gauge gets stuck at 2.11mm back from the tip.

And a 0.65mm feeler gauge gets stuck at 12.76mm back from the tip.

 

Entering those six values into an Excel spreadsheet, some formulas instantly calculate and display the tip gap, ink reservoir angle at the tip, and the main ink reservoir angle.

 

If the calculated values are not what I intended then I just pop out to the garage again and give the pen a few more whacks with a hammer.

Perhaps 3D printing would be a better way!

[secret_squirrel]

Dipper,

I just came back to check this thread after a couple days and wow. The information you provided is outstandingly helpful. I've been brainstorming some ways of manufacturing and I'll post whatever ideas I can make coherent enough for other people to understand. I do like the idea of 3D printing, and it just so happens I have a 3D printer. I can definitely give it a shot, but I'm not sure if it would work very well. I don't know how familiar you are with 3D printers, but I'll explain my reasoning for anyone who isn't familiar with them. There are two main types of 3D printers, FDM (fused deposit modeling) and SLA (stereolithography). FDM printers work by putting down layers of melted plastic down one at a time (think of a hot glue gun on a CNC machine). You can get some pretty fine resolution, but it will still be noticeable ridges on any curved surface. SLA however would be a better option as they work by using an LCD screen as a mask that cures layers of liquid resin. You can get the layer resolution on these things down to a few hundred microns. All that being said, one of the things that attracted me to your pen design was the solid metal construction and the weight that comes with it. 
Either way, I'm going to do my best to model it and I will share a link here in case anyone with the means wants to give it a shot.

Thanks again, you went above and beyond here!

[Inkyways]

Hi Dipper,

I have seen" your pen " working in the HANDS OF "PETER DRAWS'" It is amazing,  how you tested all your pens and came so far up to these pens. I love pen tools and I already have many Automatic Pens and one ruling pen. I still don't know how they work and what ink and paper is the best. Your all experiment on ink and papers give a slight idea that it is rabid hole.  I love to learn how to use them.

 

Thank you for the share and keep do what you love to do. There will be a nice bright light at the end of the tunnel.

Cyril.

[dipper]

This post is showing TWO BAD THINGS.....

 

The first bad thing is an ink reservoir slot that opens to a slightly flared gap at the tips.

The sketch above shows a highly magnified view of the pen tip, looking sideways through the slot. The inner faces of the ink reservoir slot should be as the two dotted lines, but due to poor manufacture methods the tips are curved slightly.

 

The result will be that ink held in the slot will not flow down through the flared area. The pen will not write.

 

When smoothing the inside faces of the slot I found it impossible to avoid making flared tips.

My solution is to make the pen initially with an extra long slot. About 10mm of extra length is included at the pen tips, at the start of manufacture. Slot cutting, shaping, smoothing, bending etc is all done with that extra 10mm in place. Then during final grinding and shaping of the outside of the pen tips that extra "waste" 10mm length is cut off.

Any flare caused during slot smoothing will be in the waste discarded part.

 

Here is the second BAD THING:

Pen A is good. The ink stays where it is supposed to be.

 

Pen B is bad. It has an ink reservoir slot that narrows towards the root of the blades.

A small quantity of ink or rinsing water or paint can be held up in the back end of the slot in pen B.

 

Result during use of pen B will be that the retained blob of liquid will inevitably drop down sometime during a drawing session and mix with the working ink at the business end of the slot. Unexpected red ink appearing in the pen halfway through working a light blue tinted sky can be upsetting.

 

Pen A can be tested during manufacture by submerging the entire pen in water, then lifting out of the water, draining away any water from the tip area of the slot onto a cloth - and checking to see that all water in the root area of the slot is also carried away down to the tip.

 

[dipper]

The ruling pen metal part described in posts above needs to be mounted in a comfortable handle.

 

One difficulty with modern commercially available ruling pens is their very thin handles, inherited from the designs of tools in draughtsmen's drawing sets.

 

A much better handle would be something similar to a fountain pen in diameter and overall form.

I favour wood or bamboo, but the outer tube of an old plastic biro is also perfectly useable.

 

Uni-ball "eye" liquid ink rollerballs have excellent tough plastic outer bodies, and a conveniently wide front end hole. When empty it is easy to pull out all the guts with pliers and rinse clean:

 

What shapes, at the back end of these ruling pens, work best for mounting in a handle?

 

Here are some that I have used:

If you make the metal pen from a very large old brass woodscrew or perhaps a modern stainless steel machine screw then it comes with a threaded mounting shank ready made for you.

Remember though that you will want to remove the screw from the handle for cleaning, so the screw thread should not be a tight fit in the handle.

For mounting my brass woodscrew pen in a bamboo handle I heated an identical screw in a gas flame and screwed that into the bamboo, burning a perfectly formed thread form inside the bamboo.

The brass screw pen now goes in and out easily with finger twisting only, and is wobble free when screwed fully home.

 

The middle example in the sketch above is a plain straight shank. I found it difficult to make a handle mounting hole that was tight enough to prevent wobble, but not so tight that the pen was difficult to pull out. A plain shank really needs a handle that incorporates some adjustable gripping action. There are two examples visible in the photograph that shows all my metal ruling pens, posted near the start of this thread.

 

My current scheme is to make a square cross-section pen shank, as the third example in the sketch above.

The rear of the pen body tapers to blend into the shank in the region labelled B.

The corners of the square shank are flattened off except at region labelled A.

Then the square peg A is pushed into a round hole in the handle giving a tight fit.

The pen is very wobbly in the handle when only region A is giving any grip in the hole.

But when pushed deeper into the handle, at some depth, region B will engage with the handle opening. The pen is then located securely and without any wobble, but is not difficult to pull out again. (At least, that's the theory!)

The photo of a ruling pen mounted in a uni-ball rollerball body happens to have a transparent handle that shows this A/B fitting idea in action.

 

 

 

[Ferocity]

THIS IS SUPER COOL

So excited to see this!