3D Printing

[richardandtracy]

I have an admission to make.

I have been following the development of 3D printers since I became aware of the 'Reprap' project in 2002. These fascinating machines can make stuff without the machine operator having any manufacturing skills at all, just the ability to operate a computer and load a computer model into the machine. At the moment it's not quite that simple, but it's getting there. I have always held off making/buying one because the print quality of ones I think are affordable is inadequate. About halfway through 2018 I saw a printer I thought was on the cusp of being worth getting, called the Wanhao Duplicator 7. Then two further similar printers were released, the Anycubic Photon and the Creality LD001. These new entrants into the market caused a little price war, and the prices dropped a bit, to the point where my threshold had been reached, and I got an Anycubic Photon.

It is remarkable. You can create something on a computer and over a period of a few hours, it emerges like magic from a vat of smelly, sticky resin.

My first print failed as most of it came off the manufacturing Platten, but this second run, it worked. It really does work. Sorry for the quality of photo, my camera died and the photo is from my tablet, but it shows pen parts and 2 dungeons and dragons type figures for my daughters. I am simply amazed that it really works, and the level of detail visible on the tiny parts. The biggest bit is 42mm high.


The pen cap I printed has a thread on it, and on the outside it's possible to see the 0.15mm wide & deep engraving. Truly remarkable. Fantastic for prototypes, and possibly for production of these pens.

In some ways I do have qualms. I wonder if I am seeing the first signs of the death of
almost all manufacturing industry. If it is an early herald of a disruptor technology, it has been fairly slow in coming, and at the moment is not a real threat. But, imagination can allow one to look ahead and guess what may happen. And having one of these little replicators in every house is imaginable, and think of the profound changes it could cause. No need to buy any manufactured goods. You buy a design and print it at home. So the only factories needed will be the ones making raw materials for printers. No need to ship goods half the way round the planet, no need for delivery companies, and no need for all the trucks. Or any of the workers in any of those industries... As I said, the implications could be very profound if it is a technology that takes off.

It may be a tiny herald of things to come, but it is truly remarkable.

Regards,

Richard.

[stitchnsew]

Interesting. So I've heard of 3D printers but could never visualize what they could do.( I could have googled it ,I suppose , but wasn't that curious). Anyway, is everything made out of the same material, a type of plastic? And is it stiff or pliable? I was only picturing paper, and thought 'what good is stuff that is made out of paper' haha. And how big can things be made, and what makes it or cuts it, or whatever it does? And do you have a big vat of what..a thick liquid that hardens, or a solid chunk of plastic that gets carved. And this is just connected to your computer? I guess the word 'printer' only makes me think of something flat, even though I get what 3D is, can't quite figure out the two together!

[richardandtracy]

A 3d printer lays down thin layers of plastic one on top of the other until the object is made. Very similar to the 'craft' [vandalism] of trimming the edges of pages of a book to make a shape.

There are two main ways of doing this on a domestic size machine:
The 'FDM' (filament deposition method) melts a plastic wire and lays it down on the top of the model in thin layers.
The other method is to use a liquid resin that solidifies when ultraviolet light is shone at it. There are two basic types of machine. One that has a UV laser that draws the layer into the resin (called a SLA machine) and the much more recent DLP machine which uses a UV lamp and a little LCD screen to mask the areas of resin that are to remain liquid. Again these machines solidify a thin layer but this time on a moving Platten, so the UV light always shines through the transparent bottom of the tank. As a result on these types of machines the object seems to magically be pulled up and out of primordial gloop.
The Anycubic machine I have is a DLP machine with a tiny platten, enabling objects of 120 X 68 X 150mm to be made. Not big, but a lot can be done in that size.

The biggest objects can be made with a FDM machine, and the widest range of materials may be used, from a modified starch called PLA to ABS and many other thermoplastics. The finish on an FDM machine is not as good as a resin machine, because the layers can't be much thinner than 0.1mm, which is visible and can be felt. The resin machines are, at the moment, much more limited in their materials. Basically they are limited to an acrylic like material, one type of rubber or a casting wax for lost wax jewellery making. The wax means that using lost wax casting, silver or gold jewellery can be made to a precision of 1/20 of a millimetre. That is about the limit of what you can feel, so with a polish, the items can be identical to properly manufactured goods.
At the moment only FDM machines can print a part in more than one colour.

As I said in my previous post, they are on the cusp of real usability and it's surprising to see the developments there have been in the last few years. The DLP machines only appeared at the end of 2017, and now provide an affordable entry into high resolution printing.

Away from the domestic printers, it is now possible to print in ceramic and metal powders, with high power lasers sintering the powder into a solid where the material is required. Boeing, Airbus and Rolls Royce are all using 3d printed parts in a limited number of aerospace components, and ESA are using quite a few in their spacecraft. 3d printing is coming, the question is how far it will spread.

Regards

Richard.

[wendywombat]

My friend's son has a 3D printer and I've seen some of the things he's made.
He makes jointed puzzles amongst other things!! Amazing!!

He has autism and his imagination seems to know no bounds.

I can see lots of use for a 3D printer for replacement parts for instance.. There have been medical uses reported on TV.

Have fun experimenting, Richard.

[rcperryls]

Thank you for the explanation, Richard. I also wondered how this was done but also didn’t try to find out. I am looking forward to seeing what things you create. I also think that now that these printers are affordable and likely to become more so in the future, were going to see more and more creative as well as practical uses for them. I can only wonder what comes next.

Carole

[Mabel Figworthy]

Thanks for an interesting explanation, Richard. A cousin of ours has a 3D printer and has printed some impressive objects, but often it seems to end up with "printing something because I can". It is encouraging to see your useful and usable "prints".
Like you I am concerned about the consequences, but heartened by the fact that there is, nowadays, no real need for embroidery - and yet many many people embroider! It may be that pen-making, wood-turning and other skills will become the domain of amateurs in the original sense of the word, those doing it for the love of the thing. But I doubt they will die out entirely, thank God.

[richardandtracy]

I think my daughters have downloaded whole armies of D&D models from http://www.thingiverse.com, and they will be painting them as fast as they can make them.

I want to produce prototypes of all the pens I have designed, and if the resin proves suitable in the long term, maybe make production pens that way. Then there are the display stands, and other difficult to make parts like decals, box inlays etc.

I suffered from an attack of model railways when I was a kid, something that I have managed to keep a tight rein on since, but the bug has never completely left. No, sorry, that's not quite right. I loved the model house kits I saw in the shops in W Germany when I was a kid, and eventually ended up with a model railway to make the houses more realistic.
The platen is big enough to make HO scale model houses if I break them down into separate walls and roof panels. As a start I have a full size 3D CAD model of my house, as below, which can be detailed up to include all the extras found on a 'Faller' or 'Vollmer' high quality kit:

It's also possible to print HO scale figures for the railway (I printed off an HO scale 'Lara Croft' available on Thingiverse as a trial), but models from DAZ Studio or Poser can also be posed and used, and all my girl's D&D figures can be scaled down to the right size for additional background interest. There is nothing quite like having an elf sky-boat pulled by giant eagles on a model railway...
In my defence, I'd like to say that a model railway is a fantasy setting, so why not make the fantasy fantastical?

Regards,

Richard.

[wendywombat]

I wonder, Richard, if you've seen this?
Now this motorbike is Awesome!!
https://www.bbc.co.uk/news/av/technolog ... -motorbike" target="_blank

[richardandtracy]

I confess that I had not.
It is awesome. Not a word I really like to use, but it fits.

I actively dislike the looks, and have some doubts about the engineering, particularly the headstock, but.. I cannot but feel that we are on the edge of something spectacular, a revolution in the way stuff is made. I hope not to be too stuck in the mud and be able to see how to get the best from it. There is a danger in the way many adherents are going, trying to use 3d printing for everything, even in places where it's not yet suitable. It maybe one day, but not yet, and the danger is that its reputation will be trashed because of poor design rather than not being a good tool.. At the moment I think it's a tool, one amongst many. It may become the only tool needed, but not yet.

Regards

Richard.

[fccs]

This is a very interesting thread to read. My library has a 3D printer for use (for a fee, I believe) and offers classes. I think I must investigate further.....because I can...and because I’m a bit of a geek.

[richardandtracy]

I have been working (through trial & error) to get the printed threads to work easily straight out of the printer. After 27 different size trials (each one embossed with a number so I knew what combination had eventually worked) I have threads that work straight from my printer with zero post work. The only work I need to do is a tiny bit of sanding after removing the supports. This is on surfaces that are not seen by the user.

So, I can at last show a completed fountain pen:




The cap is patterned with a 'DNA' design, and the barrel with a 'Barleycorn' style design.
The pen dimensions are:
Length Capped: 130mm
Length Uncapped: 125mm
Length Posted (with cap perched on the end of the barrel): 175mm (not very secure)
Barrel Diameter: 13mm
Cap Body Diameter: 15.75mm
Weight: 22 grams.
The nib unit with an M7.9x0.5mm thread screwed straight in.

It is remarkable how consistent the printer is. The resin overcure is the same for each print at 0.075mm horizontally on every surface. the X & Y dimensions of a circle are almost identical. On one print the diameter varied between 13.62mm and 13.70mm and could be wholly attributed to the fact that it was made using a rectangular LCD screen with a 0.047mm pixel size and the circle just falling off the edges of the pixels in some areas.

The plastic clip is a mockup of a metal one, and is way too weak to be usable, but it gives the idea.

I shall now go through slowly and produce pens of every engraving design I have. The resin cost of each pen (with resin at £38.60p per litre) is £0.63p. Electrickery & sandpaper possibly takes it up to £0.70p per pen. The nib units, and filler are about £15 per pen when bought in quantities of 10 or less.

I'm going to be using the pen a bit to see how it feels and see how the plastic lasts.
A first feel of the pen suggests that it's a tiny bit short for my taste, and I may have to grow the barrel length by 5mm.
My concern with how the plastic lasts is based on the fact that the printer uses a resin heavily loaded with UV absorbers to make it cure fast enough on the printer. I suspect the resin will continue to absorb UV light now that it's solid, and may end up self destructing as the resin is damaged by the UV light it absorbs. We shall see.

Well, thought it might be of interest to show how a 3D printer can be used for something practical rather than just because it can make things.

Regards,

Richard

[wendywombat]

That pen is Amazing, Richard!!

Well Done!!
Just look at the tiny detail! That screw thread for instance. Just overwhelmingly WoW!!!

[richardandtracy]

There are four threads I had to get right.

The screw in Bock Nib Unit has an M7.9 x 0.5mm thread.
The Section (bit that holds the nib unit) to barrel thread is M9 x 1mm twin start start thread (so 0.5mm between threads).
The Barrel to Cap thread is a M12.5 x 1.6mm twin start thread (so 0.8mm between threads).
The Cap Finial to Cap Body thread (the one used to keep the clip in) is an M10 x 1mm thread.

All of the threads have had to have their profile tweaked & diameter modified etc. to allow for the excess resin cure. As they are all different diameters and pitches, the amount of tweaking is different for each thread.
The overcure of the resin can be reduced a little by reducing the layer cure time. I have used 2 settings, 10 seconds and 8 seconds. The 10 second cure is safer as the layers stick together better and I don't have problems with the layer of cured resin being left on the bottom of the tank and not sticking to the work - basically if the resin is to cure by the layer thickness up into the resin, it will also cure by at least that much sideways - it's a feature of the process I cannot avoid, just try to work around. Both cure times need further 5 minute cure under a UV lamp after the work has been washed three times with a washing cycle of IPA (Isopropyl Alcohol) followed by a rinse with water and washing-up liquid while being scrubbed with a toothbrush. Until the 5min UV cure is done, the resin feels a little tacky on the surface. The work can be left in the sun for an hour or two to get the same result.

The grey resin I used above is much more pleasant than the green I used initially. The formulation is a bit different, and the smell of the uncured resin is no-longer eye-watering, to the extent we can do prints with the windows shut. With the green, it was imperative to open the windows to the printer room regardless of the temperature outside, otherwise the drifting smell into the rest of the house was simply unbearable.
My eldest daughter has a pot of black resin, and that seems to have the same properties as the grey.

I may make some bits in black. I think that the cap and barrel finials, along with the section and possibly cap lip always look better in black. The resin comes in a very limited range of colours. The transparent colours of 'Green', 'Honey Orange', 'Transparent' and 'Yellow' look horrible when made into pens. The only other opaque colours other than Black & Grey are 'White', 'Skin', 'Maroon' and 'Blue' (which is really a 'Duck Egg Blue' and is a colour I loath). Not sure that they are what I want to see pens made from. I may have to experiment tinting the resin myself.

Having got a working pen, I think I will now modify another model I have, and load up some models onto 'Thingiverse' to enable someone to make a pen with the same external shape as the 1920's Parker Duofold fountain pen, but with modern innards. The 1920's Parker is a classic made from hard rubber, and in reasonable condition commands £200+ at pen shows. There are thousands surviving, but not too many can afford that sort of money. Want to do it as a 'Thankyou' for those who have loaded up all the D&D models and so enabled my daughter to print her own armies...

Regards,

Richard.

[rcperryls]

That pen is Amazing, Richard!!

Well Done!!
Just look at the tiny detail! That screw thread for instance. Just overwhelmingly WoW!!!

Couldn’t say it any better!

Carole

[Serinde]

This is astonishing.

[Mabel Figworthy]

I am in awe of the thoroughness of your research and experimentation - and of the resultant pen!
It will be interesting to see how it holds up with use.

[Garnet]

Holy Moly

You never cease to amaze me Richard with ingenuity and capabilities.

The amount of research you put into this has paid off with the end result.

I wonder what will be next.

[richardandtracy]

Thank you all for your comments. The pen isn't perfect, but it's better than I had envisaged being possible from a printer this time last year.

Regards,

Richard.

[fccs]

Wow!!! That is just so cool!!!!

[richardandtracy]

I must add a conclusion to this. I made some pens, but discovered the plastic was making my skin sting, for up to 48 hours after a 30 second touch, and it was getting worse. It turned out I was allergic to the resin in the solid state. I then practiced with another chemical formulation, and found that while I wasn't allergic to this resin, it was so soft that it wore the threads away so fast I couldn't use it reasonably.

Frustrating, but I'll try new resins as they come onto the market.

Regards,

Richard