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Cylindrical thumb ring from black pool ball No 8 or Plastic

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orange
Hi, I will like here to describe 12 steps I use to make a Cylindrical thumb ring from half of black pool ball No 8

Here we discuss making a Chinese like cylindrical thumb ring such as are:

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Source: Chinese Thumb Rings: From Battlefield to Jewelry Box

You can also see some in Museum of Anthropology here China Thumb Rings Image Gallery

We are discussing how to use such cylindrical rings here How to use cylindrical thumb ring ?

I will use some experience with using white billiard pool for making lip based thumb rings in past, you can find it here Lip based thumb ring from white billiard ball or Plastic.

The Plan

Because cylindrical thumb rings are near a square in shape, material need to be high enough, we need to cut ball into 2 half, drill in center, cut outside around the hole and make a final shape.

I will material for 2 cylindrical rings, so I will make one mote thick and one more thin.

PS: I will try to use tools you or your friend can have, no big machinery as turning lathe - machine which can make precise cylinders.

Step 1: Get right pool ball

Billiard/pool balls have different sizes, you need to get large enough one

WiKipedia - Billiard ball

I select a black pool ball No 8 American-style pool – 57.2 mm (2+1⁄4 in), I can get it as single ball cheap enough about $3/piece , I have best experience with polyester based balls.

I pickup back color, because it look better and it can more easily polished.

Also number 8 is centric, it will help us mark ball to cut it into 2 equal parts.

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Note: Ball is symmetrical, it has 2 white fields with number 8 opposite to each other.

Why again billiard ball as thumb ring material ?

Original billiard and similar balls was made from IVORY Wiki Ivory, but as time go Ivory material start to be too expensive, so it was soon replaced by modern plastic.

Because thumb rings was also often produced from Ivory, balls look like logical choice as source of Ivory supplement.

However there are more possible Ivory supplements, which can be used as material for thumb rings , I will list then in conclusion.
orange
Step 2: Make a ball middle marking tool

Tools and Materials for marking tool

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Final ball middle line marking tool from piece of flex plastic

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orange
Step 3: Mark the middle of ball

Tools needed to mark middle of ball

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First I mount marking tool into middle of number's 8 on both sides with some strong nail or pin.

(Take care then you really use middle of white circle, because we will use resulted hole as a starting point for drilling later , so I use a measurement unit to check it)

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While moving marking tool around ball with help of lip on end scratch middle line with nail or pin

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Line is not well visible, we need stronger one for better checking while cutting

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To make line more visible you can use special thin marker called Paint Marker, or you can paint more thick line with some goof paint and after scratch again (visible cutting line will be back on while)

Here is a test of 2 good paints which will stick to ball you can easily get in your near store and they can be easily remove after:

- Woman nail color (I use one with metal shine, is better visible)
- While typo on paper print correction liquid

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Here is final mark ball with yellow Paint Marker, market cost around $2-$3, so yellow looks like most usable color on most color surfaces and cost sawing option.

(There is a real liquid paint inside this type of markers, shake it very well before usage to get solid line, paint from marker stick well and can be removed only with alcohol)

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Bede
This doesn't look like a plan for a cylindrical thumb ring to me, but more like one of the Korean ones.

A good cheap material to make rings from is plastic (acrylic) off cuts. They come in various thicknesses and colours. A small off cut could produce several rings. The plastic can be glued together with cyanoacrylic glues and multicoloured rings can be produced. It is easy to cut, polishes to a high gloss and is durable.
orange
No, this is purely a cylindrical thread one, I update a first entry with plan and I remove all references to while ball, I make a separate thread which will use proven procedure with 1/3 of ball for lip based thumb rings.

Sure, there are more options to get plastic usable for making a Thumb rings, like you can also contact you local seal producer, there have variety of usable plastic, like Seal Company - Economs with supervised parameters.

Issue with so many plastic today is, we can't guarantee then your material will be same then mine, so is difficult to guide users how to best work with it. Most peoples can get pool ball and it will be very similar in material, so I fell it a good starting point how to start to learn how to work with plastic.

PS: I was making for some time ship models, I will not put on my finger anything glued. Gluing for high pressure need experience which most user will not have. But I never see such colored rings, do you have photos ?
Bede
I haven't got any multicoloured ones on hand, but I will see if I can make one and photograph it soon. I was going to make some cylindrical ones on a lathe so I could easily start with a multi coloured one.
orange
I use this kind of plastic a lot during my modeling work:

Generally be careful with colored ones, crystal clear Acrylate know also as Plexiglass Plexiglas is really strong and have melting point mote then 100C.

However some colored ones are from more cheap and less strong Acrylate variants with melting point even less then 100C, basically you can test if is your Acrylate good enough by putting peace of it into boiling water which has 100C, if it don't melt is OK to us it.
osmiu
after more of the dozen pool ball plastic korean thumb rings broked on my bow , I closed the books on this type of material . maybe pool balls finded in here are cheaper ones ... poor quality ... maybe the bow is too strong for it ... I don't know ... but I will search another type of material from now one .
maybe textolit(phenolic resin with cotton sheet) , or teflon ... I'll see . I like to make thin thumb rings , and plexiglass seems to me too brittle . I didn't try it so far . Horn is hard to find here .
Daniel
Funny you should mention that Osmiu:
I have pretty much same experience with mock ivory (polyester really)
Tryed to make tenon type arrow nocks and before I new it snaped clearly off at the bottom of the tenon. Horn, hardwood and bone all work fine.
Bede
Here are some pictures of real Qing rings that I was demonstrating in 1998. One is 19th century with a 19th century arrow and the other is earlier and of better quality.
Jos?Dom
Bede, could you show a picture of that arrow? I'm interested in the fletchings style.
orange
mock ivory (polyester really) called also a syntetic ivory is worth then balls matrials, its mostly not so homogenous, because its made onlyfor feal end look of Elephant Ivory (used for knives or music instrumens), this matreail try to have same gray/while shiny areas which makes it more fragile - less flex plus its made in lines/plates - is its one direction much stronger - oposite to real ivory.
plastic korean thumb rings ... breaks

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There is simple rule for all similar plastics with melting point aroung 130C-180C:

You need to be sure to don't overheat plastic during making the ring - especialy when drilling and cutting - overheating make this type of plastic less flexible and more more fragile

From my experience generlay any plastic rings are good for low poundage bows, say to 50lb, if you have stronger bow is beter to get proven matreial like horn or jade. It will take some more time to get matreials and you need to make more cate to build a ring, but result will be probaly better. I am working on make at home jade based rings - but I will need some more time to tune the procedure so its cheap and most peoples can use it..

You can overheat real Elephat ivory too :roll:, if you have in your country peoples making knives you can try this material for making your rings:

Tagua Nut - Vegetarian ivory or Some samples of usage (You need to get larger ones of 5cm diameter), I will chat about this material later.

PS: May be you have also an issue with inner shape of this lip based rings, lets discuss this theme here Lip based thumb ring from white billiard ball
Bede
I have a ring that is so thin on the sides that I thought that it would break easily but I realised that the pressure in this style of ring was concentrated on the lip and the sides and back were only there to hold it in position.

I have a Perspex ring that I can draw 90 lb bows with so plastic is not inherently weak. However, I cut the hole out with a jeweller's saw rather than drill it out. Perhaps the lack of heat and vibration in manufacture contributes to its strength.

I will photograph the whole arrow and add it to this thread. It is of a type that had very large fletching glue on at 12, 3 and 6 o'clock. Peter Dekker makes and shoots arrows with fletching like this. The big feathers straighten out the arrow's flight really quickly.
orange
Bede, can you please send us a photo of your rings from opposite side we don't see when they are Thumb ?

I poll yesterday my contacts in Aircraft Models building community and I get technical Plexi (One I know its parameters) , I get German Plexiglas Plexiglas DE

I get brick 60mm x 80mm x 25mm for $8 (There was 30mm , but not in stock and 40mm, but I was lazy to get it , because it will need additional cutting)

Note: Perspex is another commercial name for Plexiglas

{Todo: Add foto there }

Good on technical plastic is, then have measured by 10 standards values related to mechanical features, this values in table will probably not tell you much (but are good for comparison), so I try to find for you them described verbosely:

Polymethylmetacrylate (PMMA) - ACRYLIC GLASS

Important note:

Don't use any alcohol (spirits) cleaners on Acrylate, it will get while milk color.
If you want clean Acrylate use technical benzine / petroleum based cleaners (or use one from pharmacy used in medicine) .


When I will have time I will like to make a separate thread about technical plastics and their mechanical features measured by this standards, if you are interested, for now if you are curious:

PERSPEX PROPERTIES

Comparison Table for Plastics

PS: I use a economy / budget pool balls from Taiwan, these are from of super strong and durable cast polymers and polyester like PET-P (Yes it can be from recycled pet bottles), which has at least same or better mechanical values then Plexi-PERSPEX.

However professional balls are ofter made often from much more hard, but more fragile materials like Phenolic Resin.
Bede
Orange,
I don't understand what you mean by opposite side. Cylindrical rings are symmetrical. They look the same from both sides.
orange
Ou , source of confusion is then I had in my hand so far only this type of Cylindrical based rings:
Most rings of this form that were intended for shooting had one end tapered from the inside to the outside and the other with a taper from the outside to the inside. When worn, the outside tapered portion was towards the hand. This was where the string rested.

If you wear the ring close to the base of the thumb as shown in some western illustrations, the string inevitably presses on the tendons running from the hand up the inside of the thumb (these are the ones responsible for closing the thumb). This makes it very uncomfortable with strong bows

So if cut this rings they looks on borders asymmetrical a little like letter "S", sample from museum (I pick up with combination ivory/silver, so better visible)

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The technique shown in several old photographs and in diagrams republished in Chinese Archery by Stephen Selby has the ring on the centrally on the thumb. This means that the knuckle of the thumb (the distal joint) is inside the ring and only the nail and its base are visible on the outside. So, unlike a middle Eastern ring, the thumb is not hooked through the ring. The thumb is bent so that the two inner surfaces of the thumb press against one side and the knuckle presses against the other. With this grip, you should not be able to pull the ring off your thumb until you straighten the thumb.

So this type of ring can be just simple symmetrically "D" shaped as we can see in this sample from museum:

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orange
Osimu wrote or teflon ...

Some time ago I was also repairing old Paintball guns, I have contacts to local seal producers, which uses a variety of plastics and you can get there materials in small peaces (many time for free as cut off)

I pull my contacts there, but there are old and they need to be refreshed, so be patient.

For now, I can say:

No :arrow: , Teflon (PTFE) , is not ideal choice, it's to expensive and you will be probably disappointed with result, because:

- Main reason is then, Teflon don't like pressure, it leak under it (it change its shape). Yes, there are a about 30 variant of PTFE with additives to solve this issue, some time ago I had along phone call with one of main Teflon producers under name Flexon, only usable variant will be variants with glass, but to drill/cut this variants you need to use expensive diamond tools and special cooling.

- Second reason is SAFETY, then if you heat Teflon more then 250C is very toxic and carcinogen, you can easily make this temperature when for example drilling.

Note: There a lot of new Cosmic Industry / High-Tech (read it = very expensive :-) ) plastic like PEEK or PBI, so it's not realistic to use them, good jade (nefrite, jadeite) ring will be cheaper even if you will make it on 3D laser cutting digital machine as one time job.
Daniel T.
What about ABS, the plastic that e.g. laptop cases or a computer mouse is made of? It's mechanically strong and also tough on impacts.
orange
With ABS it will be similar too as with Ecological PPR (polypropylen) based Pipe Fittings used in water/gas pipes, which you can in any local hardware store:

PPR Pipe Fittings

They looks strong and hard, but they can be starched (they are not so slick as we may be need), they are good to try make and use ring, but not for regular use.
jack farrell
Orange; Since none of the rings you posted and admire are plastic, I was wondering how you recommend drilling Jade, for instance. I know that lapidary shops sell diamond core drillers.

I always recommend antler crown as easy to work and available. The tine sections could be used for Hunnic type ear laths.

Certainly horn is available enough and cheap. I would certainly be prouder to show the guys my horn ring than my PVC one, and mort traditional. -j-
osmiu
I have 2 or 3 rings made of polypropylen . unbreakable . but too much friction . and it bend on a strong bow .
I made one ring from cow bone . femur . very shiny and smooth . a turkish one . it break at first full draw .
I have or had rings of pool ball plastic that break ... some of them even develop deep channels in them because of the string pressure (I like to keep bow at full draw for long time before release)
I have some stainless steel thick plate ... but this must be a Sisif work .
The cow horn we usually manage to find here exfoliate .
Maybe deer horn , but , again , is hard to find .
orange
I have a luck to live in country which is one most producer of both synthetic diamonds based tools for drilling/cutting and carborundum as abrasive based tools for final work.

There are ways how to drill hard material at home (see later):

- For Cylindrical ring we need relatively large and deep hole and after a bigger cut to get ring pipe shape, for now looks like the only realistic, fast and relatively cheap way how to get one time small pipe from jade with your dimensions is 2D power machinery laser, after use or small diamond machinery tools or carborundum stuff used in Jewelery.

In China they use a series of drill bits, which are inside empty, to produce such pipes to be cut later for rings.

- For lip based rings, where we need real pure hole (can be smaller) and is in relatively small deep this like approach can be tried Diamond_drilling_porcelain or more time consuming drilling with diamond dust (protect your from breading it!!!) , but it can be cheaper to use specialized let peoples working with Glass to drill it for you with Glass ultra sound or hight pressure water/abrasive drill.

Plus Jade (Chinese Green Jadeite) has hardness on Moss scale 6-6.5 , most hard material are speaking in this thread is Vegetarian Ivory with Moss 4 , generally more harder materials like Jade or plastic with glass will need investment in special tools so it will be better to discuss them in separate thread.

MOHS SCALE OF MINERAL HARDNESS

PS: I already order nice gemstone for ring(s), we need to patient until order is processed.

Osimu how strong are your bows and how thin are you strings ?
Daniel T.
I disagree with ABS being similar to PPR. PPR is much softer and mechanically weaker. I was talking about the hard stuff, not rubber. A proper horn is probably superior to most standard plastics.

I had cow horn for horn tips on a bow once, but unfortunately it peeled apart like layers of an onion.
osmiu
I don't know draw-weight of my bows . on hwarang it is written 64 and both WindFighter was 60#28" . For WindFighter I manage to find some graphics for similar one :
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but for hwarang , I don't have a clue . but I feel it stronger than Fighter .
WindFighters are history now . came in peace , go in pieces .

ps : that deep channels actually are not that deep , but deep enough to interfere with the release . so , for me ... are deep . string is regular fast-flight hwarang string . 22 strands I think . isn't 2.5 mm thick ? so ... what material for my rings ?
orange
ABS is used in high pressure pipes, outisde swimming polls and in car bupers, so it can be relative easily to get as small peace of pipe and compare it.

I will make a cylindrical ring from small PPR pipe (with right pipe size and tools it will be very fast), so we can really compare it too.

I feel here an confusion, then we are looking for most harder plastic (or other material), NO, we look for hard enough, because:

If you will apply a large pressure/force to small place of material it need to redistribute large tension inside, very hard materials have often issues with it, like:

- Local tension will crack material - it will brake apart

It can crack immediately or cracks will be microscopical and it will be accumulated over time until it breaks (it's one of type of fatigue of material )

OR

- Local tension will stretch material - it will leak/meld (deform) like rubber, but on hard enough plastics types this will be with larger force irreversible change which will grow when you will put force again

Some modern plastics can survive this type of deformations, if force is putted on them in relatively short period of time.

??? How to prevent this ???

1. Select better material :lol:

This is what is all this discussion about :wink:

Modern plastic some times have additive in form of strands, they are more restive to pressure in one direction, this generally not good for rings.

2. Change shape of ring so internal tension is better redistributed

In lip based rings make it more robust with reshaping part which string touch during draw. Here we can only try to follow generations of ring producers works on it, see variety of rings in lip based thread

In cylindrical ring we have already advantage of pipe shape, which is per design helps redistribution of tension.

3. Change force so it is applied on more material surface

Yes, make string thicker, it's not so hard because perimeter is Pi (3.14) of diameter.

PS: Mysa once show us how very thick was original Turkish strings.

Of course, having lighter bow will help to reduce force, I have 2 horse bows 45lb/30" with Dacron string and 65lb/30" with FF, I will experiment with plastics on 45lb, for 65lb I will use only original Korean lip based ring or jade (alternatively from bone) cylindrical one.

Also have draw/release done in 3 seconds instead of 20 ones will help, but it's unrealistic when you are learning how to draw with ring.
As Osimu state (I like to keep bow at full draw for long time before release) :roll:

Natural horn is good example how hard and still elastic material can be produced.
orange
Well, using a natural material will be nice, but from my experience quality now very vary, my friend is working in piercing studio and he also report then quality of horn material is lover and over :cry:

Osimu wrote:

The cow horn we usually manage to find here exfoliate .
Maybe deer horn , but , again , is hard to find.


Osimu is not native English so as me (it can be just wrong translation), but I need to point, then:

Deer have Antler, not horn, Atler is grow from bone and is like a bone and same as bone it can have inside cracks. Hrons are grom from skin and are from proteins Horn, they grow in similar way as human nails. To finish it , Ivory is grow from teeth and from dentine.

Cylindrical rings was made also from tiger bone and later from other ones.

So horn will be similar in finishing as plastic we are speaking about, so you can learn how to work with horn on plastic first.

However Anler/Bone is much harder, close to what (Vegetarian) Ivory is. We are waiting with one of my archer friend for March, hope we will have luck get good large enough Deer Antler for free, otherwise again jade ones will be cheaper.
orange
Because a real ivory is from teeth dentine , one of ideas is to use a dental materials for them.

Because dental materials are often applied under negative pressure into forms, so making even soft plastic rings make sense as starting pint of making such form. I have in family a dentist, I will try to make such ring, but I need to be sure then it will be good fit first, I have work for free, but material is expensive and I need to pay for it.
orange
I check ABS with friend who makes aircraft models, they use Hard ABS for wings and he tel me then it is relatively fragile, so I will exclude ABS for now.
Daniel T.
This is up to you. I don't want to get too technical because I feel we are loosing the point of the thread, but I'd like to say that there are many types of ABS. Perhaps your friend has a low butadiene content, in which case his material is more like polystyrene (brittle). But if you want a tough plastic, its either polycarbonate or (a proper) ABS (both are used in motorcycle helmets).

I had cow horn for horn nocks on a longbow, it peeled into layers like an onion.
orange
I manage to get a samples of technical plastics, plus friend donate me 2 different black horns and small vegetarian nut, so we will enough material for comparisons.

I will make a group photo soon.

Issue with modern plastics is then they are commonly have some additives for fit plastic to purpose, example can be a motorcycle helmets, where resistance to only one crash is needed. This is why I like a technical plastic, where you know all additives.

If somebody want to tray ABS for ring I will probably start with some old car bumper.
jsachers
Indeed polycarbonates and ABS are used in motorcycle helmets. Their purpose is to spread as much impact energy as possible over a large surface. So they are not easily deformed, but (quite) easily broken. Plus without layers and layers of finish they are very sensitive for scratches. UV rays make some of the additives evaporate so that the material becomes even more brittle with the years (helmets last app. 5-7 years).
I don't think these are desired characteristics in a thumb ring.
Being a motorcyclist myself, I could however provide you with lots of old helmets if anyone wishes to give it a try ?
orange
Yes, purpose of helmet is to break on certain force, otherwise you neck be seriously harm even when head will not.

Anyway, if I will try Acrylic Plexiglas, I can try additive free Polycarbonate like Lexan too.

I will check tomorrow it them have so usable thickens on stock.
Daniel T.
I don't know how you reached your conclusions, but I know that the fracture toughness of ABS is easily twice that of plexiglas. As orange already pointed out, it depends alot on the specific brand. In the case of ABS it depends strongly on the rubber content. Plexiglas you can buy e.g. in hardware stores could also contain a fraction of rubber to make it less brittle.

Fortunately a colleague at work is currently working with ABS and I will ask him for suitably sized scrap pieces. Then I can try a ring according to the instructions given here.
Joomong
I have seen wood thumb rings made for Korean archers. The maker uses very strong wood, carve it, and makes amkkajee or sukkajee.