3d printing

 
  Aaron Minister for Railways

Location: University of Adelaide SA
Look out for next credit card statement Mr Blacksmith! I found the celebrity photos thing quite disinteresting actually.

I know 3d prints can be stolen over any transmission medium. I am building my own printer and part of my R&D is logging the G code data being transmitted to the printer and monitoring printer outputs to make sure the firmware is doing the correct thing. It's amazingly tedious, dudes that write firmware for a living must have all their sharp instruments well secured and counseling on speed dial.

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  viaprojects Train Controller


I know 3d prints can be stolen over any transmission medium.
Aaron


lol. Photogrammetry works
  TheBlacksmith Chief Commissioner

Location: Ankh Morpork
Someone who knows what they are talking about tries to correct others views on computer security and you assume they are a criminal. lovely.
lkernan

Keep your skirt on, Aaron is a friend, this is called ribbing.
  Aaron Minister for Railways

Location: University of Adelaide SA
Keep your skirt on, Aaron is a friend, this is called ribbing.
"TheBlacksmith"
Oh, if that's the case, then I guess I'll credit the purchases I made on your credit card.
  TheBlacksmith Chief Commissioner

Location: Ankh Morpork
Oh, if that's the case, then I guess I'll credit the purchases I made on your credit card.
Aaron

Good idea and I will release the hold I put on your Swiss bank account.
  MtBeenak Train Controller

Okay, back on topic...I spent the last few evenings finishing the 3d G42 I purchased from Shapeways almost a year ago.

It is 1:43.5 (British 'O' scale) while everything else I have is 1:48.  Unfortunately I did not know this until after it arrived.  Alone or with the rolling stock it does not look too bad, but up close to one of the Haskell NAs it is a little obvious.







For some reason the paint work on the Garratt looks better in real life, but takes on a strange shine in these photos, particularly on the boiler.  I have weathered it slightly, but it needs more.  At this point I have only just finished it and test run it.  The two motor units are linked electrically and it runs really well.  I built it to run around 18 inch radius, but my layout will have at least 21 inch radius.

On the down side, the limitations of 3d printing are a little obvious.  The stepping in curved sections, visible in the Shapeways photo, is still visible in some curved areas, despite extensive sanding.  The vertical sides have a pitted finish.  I filled a lot of it with Tamiya two part putty, and that works, but reduces some detail definition.  I also had to add a few obvious details which were missing from the design and delete or alter a few which were either only on G41 or were imagined by the designer.

I am happy enough with it for now, until Mr Snoodyk has time to build me a proper model.
  dthead Site Admin

Location: Melbourne, Australia
What did you use as the mech on the G?

http://dth.railpage.org.au/pbr_emerald/projects.htm

I've yet to get any of my projects 1/2 way so it has been interesting to see your results.


regards,
David Head
  Aaron Minister for Railways

Location: University of Adelaide SA
I'd say the model was printed by sintering, did the model come with instructions or did Shapeways recommend sanding? If the print is sintered then sanding would have no effect other than to remove material leaving the same surface finish below.
  MtBeenak Train Controller

The 0-6-0 part is from two HO Roco 'F' class diesels.  I retained the Roco connecting rod and added the valve chests and motion gear from two Bachmann 0-8-0 steam locos.  The pilot and trailing wheels are SEM 12 mm wheels, mounted between the Shapeways axle boxes.  

I started this project about 25 years ago, and the mechanisms and motion gear are that old.  I had scratch built the boiler and end units from plastruct, but the detail was lacking.  If I was starting from scratch again, and using these Shapeways 1:43.5 units, I might opt for the Bachmann 1:43.5 08 diesel shunter mechanisms.  They would then be more in scale with the body.  Bachmann have a 2-8-0 Consolidation with similar valve chests/pistons and motion gear.  These can be found at second hand stalls, or as parts from Bachmann spare parts on-line.
  MtBeenak Train Controller

Does sintering mean that the material is porous, similar to the inside of a Violet Crumble?  There were no instructions and sanding works only to a limited extent, mostly to remove the stepping.   The filler helped a lot but the trade off was the amount of detail lost.
  Aaron Minister for Railways

Location: University of Adelaide SA
Sintering will cause the surface finish to look like it's made up of a bunch of tiny spheres or particles pressed together. The issue with sintered plastic is that the bonds between the particles are relatively weak. When you sand or file, rather than smoothing the high spots of the spheres back to a relatively flat finish what actually happens is the whole particle dislodges leaving a reverse defect as in you now have a (tiny) dent where the particle was, rather than a particle with a corrected flat face/edge.
  dthead Site Admin

Location: Melbourne, Australia
Sintering will cause the surface finish to look like it's made up of a bunch of tiny spheres or particles pressed together. The issue with sintered plastic is that the bonds between the particles are relatively weak. When you sand or file, rather than smoothing the high spots of the spheres back to a relatively flat finish what actually happens is the whole particle dislodges leaving a reverse defect as in you now have a (tiny) dent where the particle was, rather than a particle with a corrected flat face/edge.
"Aaron"



Shapeways "Strong White & Flexible seems to magtch your Observations Aaron. all surfaces particulrly flat look grainy.  I did some Weipa hopper cars in the stuff, and did one in another material, the other, more expensive was better. I had one cast by a local manufacturer and it is nice and smooth.  So the material is not goof for  flat surfaces.  my project page can show it on the painted sample.

David
  warp_kez Station Staff

I am looking into 3D printing myself, initially for small parts that just either do not exist or no longer exist and attract hefty eBay prices.

But one of the things I am looking at specifically is doing it myself given that consumer units are available at likes of certain office supply warehouse.  I do realise I am still looking at significant dollars.

Has this been a consideration - bring design and production into your own workshop(s)?
  rpilgrim Station Staff

warp_kez

I have been watching the development of 3D printers for 5 - 6 years and came to the realisation earlier this year that the current crop of printers in the $1200 - 1500 range are not good enough for detailed models. They would be OK for items that do not require a smooth surface with detail. If you go to printers for about $4000+ such as the B9 Creator then you are starting to get something useful.

See here:

http://b9creator.com/

I turned to using Shapeways to produce things as it is about the cheapest 3D print company around.

https://www.shapeways.com/

I have just opened a Shapeways shop called Signals Branch at:

https://www.shapeways.com/shops/signalsbranch

And I have a blog also called Signals Branch where I put the assembly instructions at:

http://signalsbranch.blogspot.com.au/

I have found this to be the best way at the moment to get into this new and interesting field.

Ray P
  dthead Site Admin

Location: Melbourne, Australia
Jaycar has a 3d printer kit for sale, but would be a toy, and knowing one guy who bought one,  has a bit of work to get it inone peiece, and not even powered it up, so if it works......

Like a lot of things if you have the money and lots of it a half decen one can be purchased ( and I'm guessing you would need over  $30,000 to get a decent one), the tool can be bought. To me there is the  second need, skill to design the object on the computer as well.

Model Railroader's december 2014 edition had a bit on 3D printing, also shapeways based.

Despite all the good humor jabs at each other, Aaron and the Blacksmith know what they are talking about here on this topic. They will agree it is a excpensive young technology still.

Regards,
David Head
  warp_kez Station Staff

Over the past week and a bit I have been reading and watching a lot of reviews.  So much information.  One underlying theme is to stay away from the tinker style printers like the one Jaycar has.

They seem to be designed for people who know what they are doing (that is not me for sure) and want to tweak every single part of it to get that fine grade print.

The whole roughness of the end result, is a concern even at 0.1mm resolution as I have even seen some from Shapeways require some sanding.

The first full model that I am working on is some 40 Ton coal wagons for my son's GWR layout.  There is someone who makes resin kits, but they have a 6 month lead time at the moment.  But all the fine detail of the rivets and support braces I fear might be too small for a printer, but the laborious task of doing it several times with styrene is less appealing.

I will be watching this thread intently.
  SA_trains Deputy Commissioner

Location: ACT
I am looking into 3D printing myself, initially for small parts that just either do not exist or no longer exist and attract hefty eBay prices.

But one of the things I am looking at specifically is doing it myself given that consumer units are available at likes of certain office supply warehouse.  I do realise I am still looking at significant dollars.

Has this been a consideration - bring design and production into your own workshop(s)?
warp_kez

Hi Warp,

Yes I am toying with this idea...

My work place has a very high end 3D printer that is no longer used and will sometime in the near future will be disposed of. The printer originally cost $180,000 installed. Yes installed, it is not just something that you can take out of a box (like an inkjet printer) and placed on a table. It is a very big machine and needs to be professionally placed into packaging to move, and then installed at the final position. It also has a "bath" for washing off the waste material.

This is a serious piece of work. The resolution is in microns and can make curved surfaces very well without the obvious "stepping". However, you can still see the layering as the models are "laid down". A hole heap of different materials are available including using multiple materials in the one build. One item I saw was a truck built with rubber tyres!

So, I am thinking about buying this and if it can be purchased for the "right" amount, then perhaps I'll have a very powerful modelling tool. (In the good 'ol days, it would have been a couple of slabs of beer and a friends ute! Smile )

DTHead

... To me there is the second need, skill to design the object on the computer as well



Well actually, this is the MOST important aspect! ANY model made is only as good as the CAD design. How any model is designed is crucial to the process. In a sense, any 3D printer, is just like a hammer. Only as good as the person knocking the nail in...

Will I get the printer? who knows. If the price is right, If I can get good enough (well frankly, has to be EXCELLENT) design skills. I don't know. One show stopper is that the printer needs to be professionally placed into transport mode and then re-installed. If this is not done, then it becomes an expensive piece of paper weight. Sad

SO, I am fairly certain the "hobby" 3D printers are most likely not going to cut the mustard, it seems clear to me that for HO-scale (or larger), you really need as good a print as possible.

Good luck with your 3D efforts!
  MtBeenak Train Controller

I bought a set of three old style skips:-

https://www.shapeways.com/model/2122050/0n16-5-skip-riveted-body-old-grease-axlebox-x3.html?materialId=6&li=ostatus

in strong, white and flexible.  They have that finish that has been referred to as sintered.  When painted in red oxide or red primer they look like rusted metal which has been painted over.  I painted the lower frame matt black and fitted old 9 mm plastic wheels, which I painted in Humbrol rust colours.  They will roll, but I gave them to someone who will use them as static models at a mine site.

My point is that the sintered finish is fine if you want a rough looking finish.  If you want a finer finish, I suggest choosing a different medium.  Shapeways offer a 'Detail Finish' and a 'Frosted Ultra Detail' finish.  I have tried the detail finish and it is better, but not perfect.  The big difference is in the use of the part.  If you are going to simply paint it and place it on the layout, a higher quality finish is in order.  However, I have found that the 'Strong (colour) and flexible' is very useful when kitbashing, as I did in building G42. I can glue to it using plastic solvent, as I do with Plastruct, and it also takes 'super glues'.  It takes taps so I can bolt to it.  The detail finish is far more brittle and not nearly as user friendly.

Mick
  Aaron Minister for Railways

Location: University of Adelaide SA
I am in the process of building my own 3D printer from scratch. To be honest, it's a 'because I can' project and I only aim to have it print slightly less crappily than most other commercial units.

I have said many times that I think all 3D printers are rubbish for decent modelling, but I have to say as I gain access to higher and higher priced technology - last count there were 12 of them near me and I regularly sit next to a $27k machine, the results get ... not much different, and are still so rubbish I'd be offended to own a model printed from one.

IMO so far, the only thing a 3D printer is useful for is for a (often not so) quick and (often very) dirty sample, fit for basic go/no go testing before I send it off for injection moulding or some other quality machined finished product.
  warp_kez Station Staff

IMO so far, the only thing a 3D printer is useful for is for a (often not so) quick and (often very) dirty sample, fit for basic go/no go testing before I send it off for injection moulding or some other quality machined finished product.
"Aaron"


That is perhaps the prevailing thought that I have been encountering.  I cannot find the article now, it has been removed as the mood degraded to a slanging match, but the gist of the article was use the 3D printers for "rapid" prototyping and when you get to the point of having a final product create a cast to mass production.

I have seen Youtube videos of people making entire HO/OO scale carriages and wagons on the printers, but the clean up afterwards.

A 21 ton OO scale steel wagon has over 150 rivets on one side alone measuring about 0.4mm - I cannot see a #D printer handling those well, but at least the supports and welds might be easier.

Hopefully, with the continued improvements in 3D printing we might start to see
  TheBlacksmith Chief Commissioner

Location: Ankh Morpork
The ability of the 3D printer to handle rivets is inconsequential, yes they can if they have the required resolution, placing them on the design is not particularly difficult either, a simple cut and paste operation. The difficulty is where those rivets are in relation to the build direction, if you get that wrong, then often they will just appear as blobs.

I was about to buy a $40,000 machine at one stage, until I came to my senses and realised these things:

1. The machine on offer could be $40K, $70K or $110K, and the only difference was the number of materials it could handle. The makers were playing fast and loose with the old 'software options' trick, you paid vastly more money for little more than some extra lines of code. After that I lost any respect for the makers.

2. The materials being sold to you for use in these machines were extremely expensive, artificially high prices, much like how you can buy a brand new laser printer for $39 but a toner cartridge for it costs $59.

3. The resolution of the device I looked at was not great, I have builds made by a US company that frankly crap all over the results from this machine. And as time goes on, the build quality will improve and you will be left with an expensive white elephant.

4. Modellers are not prepared to pay what it costs to recover the capital investment on a machine of this sort, they will all say they will use it but mysteriously go missing when you need to get them to commit. They are addicted to the cheap costing from companies like Shapeways and won't pay more for better models.

5. Many modellers can come to grips with the software to produce a 3D model, but fail to understand that a one-piece model is not necessarily the way to best utilise the additive printing process. Silly things like handrails in the design tell you the person hasn't got a clue.
  linton78 Train Controller

Location: South Coast NSW
While working in a Flight Trials Unit back in 2006 we had an early type 3D printer at our disposal. I was amazed at what it could produce, I remember the installation and sales people showing it off by printing working ball bearings. These we're not obviously structural components however as Aaron said provide you with a great prototyping method, hence the rapid prototyping label. This machine cost a lot of money and so did the consumables to keep it running. These expenses were off set by discovering problems in a component before money had been spent on manufacture and certification. Well worth the money when used for this purpose.

For model trains this type of printer technology was useless. I actually found some coach interiors I printed years ago yesterday. They are now in the bin as they were terrible.  

Today's printers seem to be a lot better and for small items, perhaps even coach interiors look to be suitable. I am sure I have heard of people using 3D prints as masters for casting parts. I guess if you only require a few masters, spend the money on the highest quality print and spend some time cleaning them up, it would be great for casting off. Not sure as I have never done it.

From what I have seen, when it comes to printing a complete wagon, I still think there is away to go.

When I look back to what we used to have at work and now what's available, things are heading in the right direction.

Linton
  comtrain Chief Commissioner

Location: Near Albury Wodonga
Hello Linton
I have a friend who has access to a 3D printer, and he is using it to help him build a 5" scale live steam engine.   When they have the drawings right, he gets the models built, cleans them up and sends them to the foundry where they are used to cast in sand, the final product.
They make cylinders, wheels, working simplex pumps valve gear funnels and domes and are learning something new every day.
Cheers
Rod
  warp_kez Station Staff

The ability of the 3D printer to handle rivets is inconsequential, yes they can if they have the required resolution, placing them on the design is not particularly difficult either, a simple cut and paste operation. The difficulty is where those rivets are in relation to the build direction, if you get that wrong, then often they will just appear as blobs.
...

5. Many modellers can come to grips with the software to produce a 3D model, but fail to understand that a one-piece model is not necessarily the way to best utilise the additive printing process. Silly things like handrails in the design tell you the person hasn't got a clue.
"TheBlacksmith"


For me these stood out as good points.  I was thinking last night about the design, and rather than try and do everything at once break it down into smaller parts like an Airfix kit.
  linton78 Train Controller

Location: South Coast NSW
Hello Linton
I have a friend who has access to a 3D printer, and he is using it to help him build a 5" scale live steam engine.   When they have the drawings right, he gets the models built, cleans them up and sends them to the foundry where they are used to cast in sand, the final product.
They make cylinders, wheels, working simplex pumps valve gear funnels and domes and are learning something new every day.
Cheers
Rod
"comtrain"


Hey Rod,

He wouldn't also work at the same Flight Trials Unit would he? The reason I ask is that there is a bloke building a 5 inch loco there at the moment. Funny if it was.

That is the perfect scenario! I am sure they would be learning a lot. It's those that do try things that make progress. Having access to and not buying at this stage in the 3D printer world is still probably the best way to go, if using it for hobby purposes.

Linton

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