How I got into 3D printing and what do I use.

As some of you will know, I love all aspects of building my competition models and like to ideally make everything within our competition team.

I first used a machine tool shortly after my 16th birthday, when I done two weeks of machine shop training as part of my fitting apprenticeship. Over the years I gained experience on lathes and milling machines and started CNC routing around about 1993 with one of the first hobby level machines.

With this entrenched background I frowned upon 3D printed parts and the euphoria surrounding the process, however I did see changes occurring, about 18 month's I decided I would take the plunge on 3D printing as I had some quite good results from cheap machines using good quality filaments.

I am quite capable at mechatronics, in fact it is the only thing that I have any formal training in, however I don't much like spending time making machines to make model parts on, rather I prefer to spend the time making actual parts for the models.

So I decided that I wanted a machine that just worked and did not need fiddling with to get results, after doing my research I decided on the Dremel 3D20, Dremel are a well known name in modelling and the machine seemed to get goodish reviews. I bought my printer second hand on Ebay for £200.



As you can see the machine is fully enclosed, I liked this idea as it keeps dust away when in the workshop and generally keeps the internals warm from the printing/heating process.

I will not go into the process of creating a 3D CAD model, maybe that could be another post, but I will basically describe the process once you have a CAD model that you have created or downloaded. 3D printers extrude thin layers of hot plastic in very accurately positions, these layers are usually between 0.05 and 0.3mm, the thicker the layer the quicker the part will get made but with less detail.

A software programme that is usually supplied with the printer slices the 3D CAD model into layers according to the selected layer height, there are a lot of clever things that the software also does to control the behaviour of the printer rather than just extruding plastic.

The clever things are such as how hollow do you want the part to be, so for example you can make parts that look like a birds bones with an aerated core (called infill in 3D terms), you can specify the shell thickness, printing speed, plastic extrude tempreature and many other things.

I loaded the printer with the plastic filament and set it off printing one of the supplied sample files which was the frog that you can see in the photo above if you look closely. The print went fine the first time, no problems, this was very encouraging, this was just using the supplied settings, no fiddling around with software settings.

After a couple more sample prints, I printed my first part which was actually a wing clip for some chuck gliders I was making for my Granddaughters birthday party.



The first prints had been pretty successful, these are all the white parts, I then bought some carbon fibre filled filament, this material was a revelation, it had better strength, was more heat resistant and had a better finish, these are the black parts. I even made an exhaust strap with it.



These are aileron torque rod horns, a screw bears down on a flat ground on the torque rod and makes a quick connection.



I mentioned the infill density, in the the photo below you can see the cross section through a part of printed fuselage pattern.



I have also made small jigs and fixture tools, this C of G stand worked out quite nicely.



So you can see that 3D printers can be quite useful in the modellers workshop, tomorrow I will cover the software side in a little more detail.

Any questions then just ask.

B.

I've been waiting for this but I don't think you've downloaded your images to your album Baz.

Edit- you're way too quick for me mate!

I seem to be able to just embed the images direct from their location unlike the North Korean forum.

I think the problem to start with was that I had too many images and it just had some text in place of the images.

Baz

The torque arms fit any servo Barrie? That would be really useful.

STF

I did not explain that too well, they go on the ends of the wire torque rod that is embedded in the wing, save a second bend and gets exactly the right length that you need.

I will get some more photo's together.

I have not done a splined servo arm yet, the printers are not super accurate like an injection moulding or machined arm, I will try it at some stage though.

Baz

Fascinating stuff Barrie, thanks for taking the time to share that, I know nothing about 3d printing apart from following Simon's projects on here, I was totally unaware there where different compound filaments available, the carbon loaded stuff is VERY interesting, the possibilities are endless!

Paul

Yes I was surprised at the different types of filament fillings and types even within the PLA (polylactic acid) type, which is what most of these small home/hobby type 3D printers use.

We must be careful to understand that the carbon fibre filled filament does not have long fibres, rather they are short ground fibres. Nevertheless the results are interesting.

Regards

Barrie

My entry into 3D printing was not in any way planned but simply my son bought me a 3D printer 'kit' for my 67th birthday!

A trained engineer although like many I spent almost my entire working life planning how to use engineering rather than actually doing it. I did get to use computers quite early on with 'building size' mainframes and using punched cards for data entry.
Although aware of the 3D printing process actually using it was right outside my experience as were the ins and outs of CAD. I realised a steep learning curve would be involved, particularly given my age.
I very quickly established that the printing material was a great deal heavier than balsa (about 10 times) and many orders heavier than the new fangled foams which I had just started to use.
Although those with the knowhow and skill could print a complete airframe, albeit with some serious structural limitations, I decided its best use would be to make specific parts for planes where the filament weight and strength could be used to advantage.
Not so many of the published design files (like Thingiverse) went down that particular path although I did find some very use bits to improve my Anet A8 printer.

My first practical use was create a printed wing rib where the dimensional accuracy, repeatability and simple scalability were a distinct advantage. A one piece rib also suited the lightweight Depron skinned wing designs I was developing at the same time.
After much experimenting this design proved to be the most suitable for a fully Depron sheeted wing.

A true scale wing section this rib is 3 mm 'thick' with a diagonal truss infill and a single sided 'web' 0.15 mm thick. It weighs 0.6 g, uses 210 mm of filament (at a cost of 0.5 p) and takes 6 minutes to print.
46 of them were used on my Antonov AN2 thus making good use of the printing process.

That rib is a good use of the printer.

The rule must be pretty old as it looks to be stamped with HM Stationary Office !!

B.

I use that rule particularly when I tire of all the Brexit shenanigans.
12 ths and 16 ths on the front, Metric stuff, 10 ths and mm, relegated to the back.
Stationary Office - very Imperial.

Strangely I actually love that rule Simon! despite spending my working life using metric I still relate to imperial.

paul d wrote: Strangely I actually love that rule Simon! despite spending my working life using metric I still relate to imperial.

It's an age thing mate, I am just the same !

I am fascinated with these machines & would love to get one, the only thing that put's me off is the programming. I don't mind admitting I am computer illiterate, think Neanderthal meets spaceman ! My question is; while I spend the next decade ( assuming I have a decade) learning how to use the design software, is there a simple way to load others designs to the printer ? For example, say I want to copy some of Simon's designs, if he is willing to share them. How would you go about that ?

crash happy wrote: I am fascinated with these machines & would love to get one, the only thing that put's me off is the programming. I don't mind admitting I am computer illiterate, think Neanderthal meets spaceman ! My question is; while I spend the next decade ( assuming I have a decade) learning how to use the design software, is there a simple way to load others designs to the printer ?

Me too Crash, the programming puts me off, I'd love to do Arduino too but I look at the chunks of language which mean zero to me and scroll on.

Crash
Maybe I will do a video of the workflow that you ask about.

If not I will write something up.

Regards

Barrie