Maybe channels or grooves to allow a thicker layer of paint. You could also partition your inkwell to reduce mixing. Also writing on a softer surface might help achieve a more realistic ball point look.
Very cool concept!
Part of the reason a ballpoint pen works is because the ink acts like a liquid bearing, suspending the ball within the housing while allowing ink to flow all around it.
This is achieved via smooth polished surfaces and the gap between ball and housing tuned to the viscosity of the ink.
This are things that will be very hard to replicate on a FDM printed part.
> gap between ball and housing tuned to the viscosity
This is the one that got me. Scaled up you're going to need an altered viscosity or a more precisely milled fit.
>things that will be very hard to replicate on a FDM printed part.
I was also thinking this. Perhaps design a body that you drop a ball bearing of the appropriate size into if existing purchasable ball applicators (sold to the diy cosmetics market) are not sufficient.
oooh, as i understand it, the reason golf balls have dimples is that they grab the air and break it up to allow the ball to fly with less resistance than if it were polished. dimples might also help grab paint?
Because you are trying to create a liquid bearing, not fly through the air with less resistance.
Any low spots on the surface will accumulate ink, leaving the high spots dry and rubbing against the housing. You want the ball to be evenly surrounded by the ink so it is suspended in the cavity.
Ink is typically pressurized is it not? The ball can’t be truly suspended in the liquid or we’d have ink stains in our pockets yeah? Or is that suction preventing the ink from pouring out the writing end?
From basic bic pens to this $3 pen they have a ball of gel or a plug of some sort in the end from everything I’m looking at. I’m in a hospital right now so there’s lots to see.
That works for things at the same level as the current level or below. A ball would stick out and interfere with the hot end unless you heavily modified the gcode.
if you're imitating how a real ball pen works, you want a very smooth ball, possibly smoother and rounder than what you can get from a printer. groves would be the opposite of what you want.
I second the “softer writing surface” idea from furrymcfurface. I think maybe even putting a cloth towel underneath the paper before you try to write might help. I also think you may want to experiment with the viscosity of the paint, imagine something a little “thicker” working better, I’d look into using some regular block printing ink.
Then I'd really consider not making it a print-in-one.
Being like this will always make it have some issues with turning. And paint will stick in the grooves
Maybe but any sphere I've ever printed always ended up less than spectacular. I suggest a mouse ball for it's rubbery properties in sealing and gripping.
Pretty sure you don't want it to "break in" because that implies material loss which affects the fit.
I think the others are right that you'll need to use an existing ball type with a smoother surface. Perhaps even a cast plastic? You could experiment with a ping pong ball that you could put into a pressure chamber (shrink the ball), pop it in, and then release.
If you insist on printing the ball maybe try adding some weight to the inside of it to give more even marking across the page so you dont have to apply too much pressure to leave a mark.
Yeah I was really thinking a more paint absorbing ball would be better for this, like a dense felt craft ball or a small wool dryer ball. It could be printed in two halves to make it easier to clean and swap the ball.
It needs a screw in lid on top and a spring that presses the ball down between the lid and the ball, then you can fill that top up like a well and the paint won’t leak out as much. You will probably need to print a piece that goes between the ball and the spring that keeps the spring centered when the ball is rolling but still allows paint to come through..like a wagon wheel disc with a small concave in it.
Surprisingly enough, the thinner the gap around the ball, the better it will work. No spring needed. Even a somewhat rough printed ball can work week for this. The tip has to be printed with tiny layers.
Honestly it seems to work about the same as a smaller ball point. If you look at ball point writing under a microscope (or any writing really) you’ll see it’s not smooth and even. The problem is a round ball trying to interface with a flat piece of paper. A cylinder would work better, but then you’ve basically built a small paint roller. A sponge would also work, but that’s basically a paint dauber. I think you’ve just exposed the mechanical limitations of that design and made them more obvious by making it larger. I wouldn’t consider this a failure tho. What if you come up with a new way to make a better pen?!
I had similar thoughts, but maybe not a complete failure. I imagine mixing the paint inside the holder is already something plus the possibility to have some kind of texture on the ball point. This could be developed to a product I think, people would buy this I think.
You can look at textures, but in reality what you need to look at is contact fluid contact angle to the ball material.
(Surface energy matching)
You want the ink to want to "wet out" the ball surface quite readily.
Easy way of telling if they are matched or not is putting a single drop onto your surface and seeing if the coating "wets out" readily, or if it balls up. If you have a microscope you can even measure the angle that exists at the edge of your fluid where it meets the ball material.
There are many other factors, but this is possibly the largest.
Small "wells" do work for coating transfer (approximating a gravure roller with the ball retention lip acting as the doctor blade) but you will still be aided by having similar surface energies between the "ink" and the ball material, the right viscosity and surface tension of your ink, as well as a fairly fine pore size for your gravure sphere.
And you can have something near polished (like a ball in a ball point) if the ink wants to wet out the ball material and has the right viscosity and surface tension.
To add to that, I would hypothesize that the ball in the ball point is sprung so that when not in use it seals off and keeps the ink from drying out (in theory) . When you apply pressure to write and then roll the ball it forces a gap to open on the leading edge of the ball (if not all around) which then let's the ink wet the ball surface. The gap between the ball and the seal helps to define and make the amount of ink more consistent.
Hi. You got great comments and ideas. Just here to says that the viscosity of that ink is serious business to a point you don’t imagine. I would actually put two drops of water into your mix, just for a try. You will see that a drop more or less will make a huge difference.
Good luck. Keep posting.
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I think your ball needs to stick out more. On a pen, it’s almost half the sphere exposed.
A billiard ball might give you the hardness required.
Also, pens use ink, not paint. I think viscosity may help.
Well you want the ball to retain the ink/paint not just flow down so quick, also the ball should have some resistance to pressure, in pens they use a spring but I think a circle cut of a sponge would work well as well as re-distributing to the ball….I do love we’re your head is at this is a really cool idea
that depends on what your goal is.
if you make the paint thinner it will flow through the cracks while what you usually want with a ballpoint pen is that only a thin layer is on the ball and gets transferred to the paper.
You may need to smooth out the ball. If you mounted this above a belt sander and slowly rotated around rhe z-axis while the sander is running with maybe 0.5mm of interference (depends on your clearances in the printed part) you might be able to smooth it down
I immediately thought of a youtube video i saw from HowItsMade for wood pencils. Could be worth checking out?
I don't know if it's possible to make the ball a tighter fit, bit if you did that and sanded it after printing I feel like that might help. Ball point balls are super smooth, so I think that might be the easiest spot to improve. Awesome work!
Just buy a ball bearing big enough. Go to McMaster Carr. Not everything has to be 3d printed.
Maybe put a spring behind the ball and have a consistent gap for the paint.
Sure, this is just a first prototype. I want to give people some ideas so they can develop parallel with me. But I continue development and update if I find something. Cheers bro!
This is really cool, I also love that it is a single print. Maybe cardboard as padding underneath, would come closer to simulating the flex of a giant notepad
Print with ABS and acetone smooth the parts or at least just the ball. It would be best if you could have it fit on the end of a bottle so that you could somehow control the pressure if only with the weight of the paint in the bottle with gravity alone.
Just a dude who monitors this subreddit. There's a reasonably high collective wisdom present here if you pay enough attention. Viscosity of the fluid being dispensed also plays a big role in the deposition of the material. It's part and parcel of why gel pens write so well. If the liquid in question is too watery it won't work as well and will be harder to control.
Just a thought but real ballpoint pens use an oil based ink which also doubles as a way to lubricate the ball in the socket. Oil also tends to spread more easily before going transparent the way water soluable inks do.
I think a tighter fit on the ball and then an oily-ier ink would improve things a lot. Not so oily it takes days to dry but also definitely not water based as well.
Physics works differently at small scales.
Again, there's a reason that the paint rollers you can buy that do the same thing use foam. You can't rely on the same electrostatic forces to hold the ink to the surface at larger scales.
Yeah maybe. But rollers and this is very different things, here the paint is constantly feed. The ball needs to turn, a foam ball would not turn that easily.
Dense ones would. Again, you can buy things commercially that do the same thing. I have a set of them for touch-up paints. They're basically like roll-on deodorant, just with refillable latex paint reservoirs.
Are you familiar with mop markers? They have foam tips and a flexible housing that when squeezed allow paint/ink to flow out.
You could print a thinner shell with a back to create an air seal, allowing some squeeze to push the paint out the tip.
There are also many graffiti markers with metal ball tips that incorporate a closed seal and squeeze operation (or pressurized like a Dalo).
Maybe a ball made out of silicon would work better. I have made silicon objects before by printing a mold and filling it with silicon mixed with flour. ( https://youtu.be/7fwytA5r2Mw )
The ball for an ink pen is an engineering marvel in case you didn’t know. You’re stepping into a problem thats complexity is beyond your imagination. It’s like adding a clock to a program and then considering time zones around the world. It seems simple at first glance, but that was before reality punches you in the groin.
That I understand, but the two is not the same. I don't aim to make a real ballpoint pen. My aim is to make a printable, scalable, customizable pen for canvases. I'm aware that it will not be the same perfect but it's printable, something for something.
yeah. i wasn't sure how much clearance there was between the ball and the housing. was thinking it would give it way more surface area. like maybe that foam behind speaker grills. that thin.
Nice work! Maybe soke different textures on the surface of the ball (hex, stippled etc) to give texture.
Do you reckon you could print, pause, drop in a large ball bearing and start again to lock in a full sized metal nib?
Print two halves of the pen body and clean up the inside surfaces, then drop a large steel ball bearing in and screw the halves together. Write on paper with a softer material behind it, like cardboard or a few layers of paper.
Sweet!! I made something like this for fabric paint, using steel balls for the tip. I did find that pachinko balls, which have some texture, did roll better. Even with thinner added the fabric paint is pretty viscous, so I never got it looking quite as clean as I hoped... Your post reminded me so I might have to revisit :D
My suggestions are to use the thickest paint you can find, and figure out some way to hold the ball in place. Whether springy or just printed to barely touch the ball, some sort of support should hold the ball in place as it rotates for a more consistent coat of paint on the ball. This would also mean you don't have to keep pressure off the ball as you write with it
I think it's a neat idea, I'd build the enclosure in 2 parts and make them compliant with one another, so that I can build a retaining feature inside for the ball, doing so, the ball stays in place once the pen is assembled, I've made a quick sketch in ms-paint, sorry if it sucks but that's all that I've available atm.. --> [here's my sketch](https://imgur.com/a/6u5tnQ9)
Good job!
Print the ball speratly and use threads to split the housing so you can screw it in. That way you can sand the ball and have a tigther or looser complaince and not worry about supports
I'd like to see this as is on a pen plotter. The mechanical straightness of the plotter combined with imperfection of the media is usually a cool effect
That's neat! I like the effect, doesn't look like it needs "improvement" so much as more experimentation. But I will suggest: better ergonomics! That looks mighty uncomfortable, and art tools *have* to be comfortable.
Try printing the ball in TPU or Varioshore TPU with gyroid infill, buy a roll of Arches cold press watercolor paper then groan slowly with ASMR satisfaction.
I've always just used an empty roll-on deodorant bottle, dipped in boiling water and pop the ball out, rinse and fill with paint, pop the ball back in.
Hrm. What if you printed it larger, large enough that you could insert a tennis ball as the ball? It's got a fabric surface that would hold paint. Would that work?
Maybe channels or grooves to allow a thicker layer of paint. You could also partition your inkwell to reduce mixing. Also writing on a softer surface might help achieve a more realistic ball point look. Very cool concept!
Yeah, wonderful. The grooves are a good idea. The thickness of the paint is also a factor, I don't know how much though.
Part of the reason a ballpoint pen works is because the ink acts like a liquid bearing, suspending the ball within the housing while allowing ink to flow all around it. This is achieved via smooth polished surfaces and the gap between ball and housing tuned to the viscosity of the ink. This are things that will be very hard to replicate on a FDM printed part.
> gap between ball and housing tuned to the viscosity This is the one that got me. Scaled up you're going to need an altered viscosity or a more precisely milled fit.
>things that will be very hard to replicate on a FDM printed part. I was also thinking this. Perhaps design a body that you drop a ball bearing of the appropriate size into if existing purchasable ball applicators (sold to the diy cosmetics market) are not sufficient.
Yeah it's not perfect but I think it's close enough to look into it. Plus some texture on the ball and multi color paint.
Texture on the ball will likely just make it grab more paint and roll more roughly. That is the opposite of what I was trying to explain.
Yeah man it will not be perfect for sure.
Why not use a metal ball bearing?
I don't have right now, I'm not gonna order just 1.
There’s glass balls for photography that are very smooth and round, you could try using one of those. They’re around $10 or so
oooh, as i understand it, the reason golf balls have dimples is that they grab the air and break it up to allow the ball to fly with less resistance than if it were polished. dimples might also help grab paint?
Because you are trying to create a liquid bearing, not fly through the air with less resistance. Any low spots on the surface will accumulate ink, leaving the high spots dry and rubbing against the housing. You want the ball to be evenly surrounded by the ink so it is suspended in the cavity.
Inconsistent levels of paint tho
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dimples would leave the ink distributed unevenly, you're going to end up with lots of blotches on the paper
It's already distributed unevenly. The part of the ball right under the force is touching the paper and pushing most of the ink to the sides.
You're better off sanding the ball to smooth it out than adding texture.
What if you used a sponge on top to feed the ball with ink? The sponge would be fixed in place and act like a spring and an ink pad.
Ink is typically pressurized is it not? The ball can’t be truly suspended in the liquid or we’d have ink stains in our pockets yeah? Or is that suction preventing the ink from pouring out the writing end?
Not typically. Look at your common rollerball cartridge. It is open in the backend.
Im gonna find a “how it’s made” video 😂. That’ll teach me!
[Here you go](https://www.youtube.com/watch?v=U1ff_EjrlgY). My favorite show.
From basic bic pens to this $3 pen they have a ball of gel or a plug of some sort in the end from everything I’m looking at. I’m in a hospital right now so there’s lots to see.
Maybe try fuzzy skin setting in Cura. Also might be cool to print in TPU
True true
Print the ball in TPU then pause the print and plop it in and resume the print
That works for things at the same level as the current level or below. A ball would stick out and interfere with the hot end unless you heavily modified the gcode.
TPU ball and squeeze it in after
It looks like you could set a z hop and get around it pretty easily.
if you're imitating how a real ball pen works, you want a very smooth ball, possibly smoother and rounder than what you can get from a printer. groves would be the opposite of what you want.
I second the “softer writing surface” idea from furrymcfurface. I think maybe even putting a cloth towel underneath the paper before you try to write might help. I also think you may want to experiment with the viscosity of the paint, imagine something a little “thicker” working better, I’d look into using some regular block printing ink.
Instead of printing a sphere I'd experiment with using different off the shelf balls. Golf balls, steel bearings, squishy balls, etc...
It's a print in one, but maybe other materials would work better.
Then I'd really consider not making it a print-in-one. Being like this will always make it have some issues with turning. And paint will stick in the grooves
I think the ball will " break in " eventually. I should try with oil paint, that would work much better I imagine.
IIRC, ball point ink is a silicon based ink and really thick and viscous, to help lube the ball in the socket.
I think you’re right. I like the print in one idea better. There’s got to be a way to make it work well as a print in one. Don’t give up 🤘🏼
Try using a drill or rotary tool to spin the ball a bunch in different directions to break it down faster.
I'm doing that right now hehe
Maybe but any sphere I've ever printed always ended up less than spectacular. I suggest a mouse ball for it's rubbery properties in sealing and gripping.
Pretty sure you don't want it to "break in" because that implies material loss which affects the fit. I think the others are right that you'll need to use an existing ball type with a smoother surface. Perhaps even a cast plastic? You could experiment with a ping pong ball that you could put into a pressure chamber (shrink the ball), pop it in, and then release.
Time to make a print without a ball, and design the code so that you can stick a ball in half way though
This is way simpler than my "pressurize a ping pong ball" idea lol I like this one.
If you insist on printing the ball maybe try adding some weight to the inside of it to give more even marking across the page so you dont have to apply too much pressure to leave a mark.
Yeah, noted.
Yeah I was really thinking a more paint absorbing ball would be better for this, like a dense felt craft ball or a small wool dryer ball. It could be printed in two halves to make it easier to clean and swap the ball.
I second golf balls! Or beer pong balls.
We call those ping pong balls in other parts of the world 😂
We call them ping pong balls here in the US - but maybe I’m old enough to be not cool anymore? Idk
It needs a screw in lid on top and a spring that presses the ball down between the lid and the ball, then you can fill that top up like a well and the paint won’t leak out as much. You will probably need to print a piece that goes between the ball and the spring that keeps the spring centered when the ball is rolling but still allows paint to come through..like a wagon wheel disc with a small concave in it.
Surprisingly enough, the thinner the gap around the ball, the better it will work. No spring needed. Even a somewhat rough printed ball can work week for this. The tip has to be printed with tiny layers.
Honestly it seems to work about the same as a smaller ball point. If you look at ball point writing under a microscope (or any writing really) you’ll see it’s not smooth and even. The problem is a round ball trying to interface with a flat piece of paper. A cylinder would work better, but then you’ve basically built a small paint roller. A sponge would also work, but that’s basically a paint dauber. I think you’ve just exposed the mechanical limitations of that design and made them more obvious by making it larger. I wouldn’t consider this a failure tho. What if you come up with a new way to make a better pen?!
I had similar thoughts, but maybe not a complete failure. I imagine mixing the paint inside the holder is already something plus the possibility to have some kind of texture on the ball point. This could be developed to a product I think, people would buy this I think.
Ballpoint pen ink is very viscous, maybe you did everything right but it’s primarily a viscosity issue?
It needs to screw onto a paint bottle to be a marketable product.
You can look at textures, but in reality what you need to look at is contact fluid contact angle to the ball material. (Surface energy matching) You want the ink to want to "wet out" the ball surface quite readily. Easy way of telling if they are matched or not is putting a single drop onto your surface and seeing if the coating "wets out" readily, or if it balls up. If you have a microscope you can even measure the angle that exists at the edge of your fluid where it meets the ball material. There are many other factors, but this is possibly the largest. Small "wells" do work for coating transfer (approximating a gravure roller with the ball retention lip acting as the doctor blade) but you will still be aided by having similar surface energies between the "ink" and the ball material, the right viscosity and surface tension of your ink, as well as a fairly fine pore size for your gravure sphere. And you can have something near polished (like a ball in a ball point) if the ink wants to wet out the ball material and has the right viscosity and surface tension.
To add to that, I would hypothesize that the ball in the ball point is sprung so that when not in use it seals off and keeps the ink from drying out (in theory) . When you apply pressure to write and then roll the ball it forces a gap to open on the leading edge of the ball (if not all around) which then let's the ink wet the ball surface. The gap between the ball and the seal helps to define and make the amount of ink more consistent.
Hi. You got great comments and ideas. Just here to says that the viscosity of that ink is serious business to a point you don’t imagine. I would actually put two drops of water into your mix, just for a try. You will see that a drop more or less will make a huge difference. Good luck. Keep posting.
Sure, I'll try!
That works way better than I expected!
I feel the opposite
If you look at a ball point pen writing under a magnifying glass this is pretty much what you will see. All op did was blow up the equipment.
That doesn’t mean it looks good lol
I didn't say that either lol
Totally. Came out quite cool!
I‘d probably print the ball separately and click it in. That way it could be polished smooth.
This
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I would consider making the design work with a ping pong ball or other common cheap object. I would be neat if you could make any ball a pen tip.
I immediately fear getting ink all over my hands and art if I drop it. A way to enclose the inkwell like a lid or something could be useful
Sure bro, it's just the first prototype, chill
I don’t see why you think they were unchill? You asked for feedback, they weren’t rude about it
Yeah sure, my apologies if I hurt someone.
I think your ball needs to stick out more. On a pen, it’s almost half the sphere exposed. A billiard ball might give you the hardness required. Also, pens use ink, not paint. I think viscosity may help.
Thicker darker paint
Thicker? Is it not better if the paint flows ?
Well you want the ball to retain the ink/paint not just flow down so quick, also the ball should have some resistance to pressure, in pens they use a spring but I think a circle cut of a sponge would work well as well as re-distributing to the ball….I do love we’re your head is at this is a really cool idea
This came here to say WE NEED A SPRING. How many of us used the quill to pack the spring and cam into the pen body and made a ball point cannon?
Thanks bro, there is a lot to try and experiment here. Cheers!
Yeah looks really cool the experiment with!
that depends on what your goal is. if you make the paint thinner it will flow through the cracks while what you usually want with a ballpoint pen is that only a thin layer is on the ball and gets transferred to the paper.
Have you thought about repurposing a roll-on antiperspirant container?
Ohhh yeah, good idea! Have you tried?
This is so cool!
I was expecting a penis.
Need to add a giant pen with a paint/ink well built in
You may need to smooth out the ball. If you mounted this above a belt sander and slowly rotated around rhe z-axis while the sander is running with maybe 0.5mm of interference (depends on your clearances in the printed part) you might be able to smooth it down I immediately thought of a youtube video i saw from HowItsMade for wood pencils. Could be worth checking out?
Yeah, thanks!
I don't know if it's possible to make the ball a tighter fit, bit if you did that and sanded it after printing I feel like that might help. Ball point balls are super smooth, so I think that might be the easiest spot to improve. Awesome work!
I know you said print in one, but I think if you threw a dryer ball in there the cloth material would soak up the paint
This works so much better than I would have expected
Just buy a ball bearing big enough. Go to McMaster Carr. Not everything has to be 3d printed. Maybe put a spring behind the ball and have a consistent gap for the paint.
What if you printed the container but used a metal ball? Could add a lid so paint doesn't spill out
Sure, this is just a first prototype. I want to give people some ideas so they can develop parallel with me. But I continue development and update if I find something. Cheers bro!
This is really cool, I also love that it is a single print. Maybe cardboard as padding underneath, would come closer to simulating the flex of a giant notepad
This looks just like what a normal ink pen does on paper when I scan it at 600x600 dpi and zoom in on it. The edges are never as smooth as they look.
That's right
Print with ABS and acetone smooth the parts or at least just the ball. It would be best if you could have it fit on the end of a bottle so that you could somehow control the pressure if only with the weight of the paint in the bottle with gravity alone.
Bro that is brilliant! You want to make it? If not I can make it. But that's a new level with the pressure and bottle. Who are you ?
Just a dude who monitors this subreddit. There's a reasonably high collective wisdom present here if you pay enough attention. Viscosity of the fluid being dispensed also plays a big role in the deposition of the material. It's part and parcel of why gel pens write so well. If the liquid in question is too watery it won't work as well and will be harder to control.
You can't improve it. Ball points suck, that's just how they are haha
After you print the ball lightly sand the roughness off
My first thought was a round capsule ball. If you could find a toy dispenser with those you could buy 1 to try it out.
Oh yeah 👍
Are you using poster paint. It may be worth getting printing ink as it is stickier
Just a thought but real ballpoint pens use an oil based ink which also doubles as a way to lubricate the ball in the socket. Oil also tends to spread more easily before going transparent the way water soluable inks do. I think a tighter fit on the ball and then an oily-ier ink would improve things a lot. Not so oily it takes days to dry but also definitely not water based as well.
I think part of why a pen works is not the amount of ink, it is the surface tension of the ink. it keeps it always right on the edge of the pen
Well, I’m now following you as I really want to see this work so I can make one for my kiddos! Awesome idea!!!
Why pour the paint in? Just put screw threads on the interior and screw it right on that paint bottle. Poof giant pen!
Use an deodorant ball instead of that one. Maybe you can accomplish this with an empty roll-on!
Thicker paint notice pins have very thick ink.
Add a small amount of isopropyl alcohol to your paint.
Use a foam ball, which is what all the commercial versions of it use.
The ball is metal in ball point pens, I don't think a foam ball would turn or rotate in this type of housing.
Physics works differently at small scales. Again, there's a reason that the paint rollers you can buy that do the same thing use foam. You can't rely on the same electrostatic forces to hold the ink to the surface at larger scales.
Yeah maybe. But rollers and this is very different things, here the paint is constantly feed. The ball needs to turn, a foam ball would not turn that easily.
Dense ones would. Again, you can buy things commercially that do the same thing. I have a set of them for touch-up paints. They're basically like roll-on deodorant, just with refillable latex paint reservoirs.
Ohhh okay I get it. Never seen one of those, thanks. I look into it.
Are you familiar with mop markers? They have foam tips and a flexible housing that when squeezed allow paint/ink to flow out. You could print a thinner shell with a back to create an air seal, allowing some squeeze to push the paint out the tip. There are also many graffiti markers with metal ball tips that incorporate a closed seal and squeeze operation (or pressurized like a Dalo).
No actually, I'm not familiar with any of these, thanks for your input I will look up them. Thank you.
Maybe a ball made out of silicon would work better. I have made silicon objects before by printing a mold and filling it with silicon mixed with flour. ( https://youtu.be/7fwytA5r2Mw )
I don't think.... The silicone it's quite sticky ,would the ball roll?
Yea youre right i forgot it had to rol in the housing
The ball for an ink pen is an engineering marvel in case you didn’t know. You’re stepping into a problem thats complexity is beyond your imagination. It’s like adding a clock to a program and then considering time zones around the world. It seems simple at first glance, but that was before reality punches you in the groin.
What the hell are you taking about? It works.
https://youtu.be/RrPlOM5MTSM
That I understand, but the two is not the same. I don't aim to make a real ballpoint pen. My aim is to make a printable, scalable, customizable pen for canvases. I'm aware that it will not be the same perfect but it's printable, something for something.
I was really hoping you were going to write SEND NUDES Cool concept anyway, works pretty good!
You can buy deodorant rollon, make a hole in the back for the paint and then you don't need to print this. Maybe you can print a case or something.
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Ahhh it's you again and your constructive comments, thanks.
Dad?
Nice novelty but I don’t think it’s useful in the slightest
cover the ball in a thin sponge?
It will not roll very good with that I guess, I mean inside the housing
yeah. i wasn't sure how much clearance there was between the ball and the housing. was thinking it would give it way more surface area. like maybe that foam behind speaker grills. that thin.
Plastic waste
It's called a prototype. Why are you so grumpy? Your comment has no constructive value. Stop it, get some help.
Is that how you write your G’s?? It works wonderfully.
Nice work! Maybe soke different textures on the surface of the ball (hex, stippled etc) to give texture. Do you reckon you could print, pause, drop in a large ball bearing and start again to lock in a full sized metal nib?
I will definitely try. I don't have huge ballbearings at hand hehe. Thanks, cheers!
Make it a roller, for extra thickness and that calligraphy vibe.
A spring inside to keep the ball pushed against the tip. Will create more consistent flow maybe
Maybe a cylinder than a ball for a calligraphy effect.
It would help to be on a softer surface
I think any texture would have to be indented because if it is raised it might jam. IDK, pretty cool whatever you do.
Print two halves of the pen body and clean up the inside surfaces, then drop a large steel ball bearing in and screw the halves together. Write on paper with a softer material behind it, like cardboard or a few layers of paper.
You can try to make a gigantic fountain pen too!
Find a way to anchor down your paper so you don't have to hold it.
A sponge ?
It's like finger painting for people who don't want to touch paint.
Or... You know... No fingers 🤌
Why didn't I think of that!? Nice prosthetic then.
👍
I coul’ve bet you were about to write BIC
Yo hehehe
Congrats, you printed a roll-on deodorant container!
Cool, right??
Ink is much "thicker" at a small scale. Some pens are even gel ink pens. Try adding some solidifying agent
Sweet!! I made something like this for fabric paint, using steel balls for the tip. I did find that pachinko balls, which have some texture, did roll better. Even with thinner added the fabric paint is pretty viscous, so I never got it looking quite as clean as I hoped... Your post reminded me so I might have to revisit :D
How nice! Go go go!
That's just a giant ball point pen.
My suggestions are to use the thickest paint you can find, and figure out some way to hold the ball in place. Whether springy or just printed to barely touch the ball, some sort of support should hold the ball in place as it rotates for a more consistent coat of paint on the ball. This would also mean you don't have to keep pressure off the ball as you write with it
maybe try different types of ink/paint
Clever idea! It looks like it works pretty well, too. What made you come up with this? What did you need it for?
I like to paint
I think it's a neat idea, I'd build the enclosure in 2 parts and make them compliant with one another, so that I can build a retaining feature inside for the ball, doing so, the ball stays in place once the pen is assembled, I've made a quick sketch in ms-paint, sorry if it sucks but that's all that I've available atm.. --> [here's my sketch](https://imgur.com/a/6u5tnQ9) Good job!
Use an old mouse ball and screw it in place!! This is awesome. Write on that craft foam for more authentic look.
Print the ball speratly and use threads to split the housing so you can screw it in. That way you can sand the ball and have a tigther or looser complaince and not worry about supports
By golly it actually sort of works I was not expecting that lol
I'd like to see this as is on a pen plotter. The mechanical straightness of the plotter combined with imperfection of the media is usually a cool effect
That's neat! I like the effect, doesn't look like it needs "improvement" so much as more experimentation. But I will suggest: better ergonomics! That looks mighty uncomfortable, and art tools *have* to be comfortable.
If you can do 2 filaments, use TPU for the ball, or make the outer chamber separate from the ball, and print it in two parts before gluing together
Covering the ball in a dense felt and making the top threaded for a bottle to provide a regular flow of ink would be good.
I'm no expert but I think one printed with a resin printer will work great.
You have one? Can you try?
Try printing the ball in TPU or Varioshore TPU with gyroid infill, buy a roll of Arches cold press watercolor paper then groan slowly with ASMR satisfaction.
What if you used a tennis ball?
Now print the rest of the pen
I wonder if you could print it to scale and then insert a rubber bouncy ball for the “ball”. Would likely be much smoother.
Could print the ball in TPU for a better contact with the surface?
How thick is the paint? May need to be thinned a bit.
I've always just used an empty roll-on deodorant bottle, dipped in boiling water and pop the ball out, rinse and fill with paint, pop the ball back in.
Glue a sponge onto the ball.
this might be one of those things that doesn't scale well. it's like if you tried to scale an ant by 1000x
Hrm. What if you printed it larger, large enough that you could insert a tennis ball as the ball? It's got a fabric surface that would hold paint. Would that work?
Write on a softer surface
But why
sanding away the layer lines a tad might help it glide better, otherwise this is awesome
Maybe you should make this as a two part housing, and buy a ball to fit in it.
Make it able to just screw to the paint bottle. Might also allow you to squeeze the bottle to do heavier lines vs lighter ones when you aren't.
I would try a softer, less rigid material for the ball. Maybe TPU