I am a bit nervous about buying anything else 3d printed because of the 3 things I have so far two are effectively unusable. One has a herringbone pattern down the sides and the other looks as if it was carved from balsa and is for want of a better word, very hairy. The third was OK after considerable rubbing down, which defeated the whole object really, I could have bought a Dundas kit for only £1 more and it would have been quicker.
Am I being unreasonable to expect a better finish?
If not how do I make sure I am getting a good job, because all the ones I bought so far looked OK in their pictures. :(
Good question. 3D printing is not always an easy answer and the models always need work, sometimes a lot. If you're happy to build Dundas kits, go that way. I think you'll get more pleasure and satisfaction from the hobby that way.
Peter
You pay for what you get in 3D printing. If it looks cheap then it will be made of the base type plastic which gives a ridged, hairy finish. That's fine for stuff like couplings or underfloor detail but not for body sides and boilers and chimneys/domes. It is possible to make them presentable if viewed from a distance but it involves a lot of work. You need to pick the "Smooth Fine Detail" finish for best results. You'll still have to do some work but it's mainly cleaning up and possibly some filler to smooth things out, but nowhere near what you'd have to do on the older material. 3D printing still hasn't reached the type of finish you get on resin, whitemetal and plastic kits, though it is now light years ahead of what it used to be! You will note that Narrow Planet, for instance, although they use a base body from the 3D process they still use thin metal overlays for detail such as doors and ventilation louvres. that should tell you what to expect.
My only advice is don't buy the cheap stuff however tempting.
Quote from: Hobby on December 07, 2019, 08:35
My only advice is don't buy the cheap stuff however tempting.
I was, I did, and I binned it. Life is too short to shave a bogie. :(
Stephen
I run a (surprisingly large) number of printed locos on Angst; some are bodies from Chris Ward (when he still ran the company) Others from Shapeways. Do get the finer detail print if ordering from Shapeways.
Others here have noted how you may mitigate the roughness on prints. I don't bother - I may have been fortunate in my purchases.
It also probably helps that my locos are all painted matt; there's nothing like a gloss finish to show up surface issues, I think.
Hope this helps
Good point about paint. It's one thing that shouts "toy train" to me is a gloss finish with gloss varnish on top! OK you may see the odd photos with a truly gloss finish in Real Life (usually outside the place it was built/rebuilt) but how long did that finish last? An hour or two until if rained (UK and Northern Europe) or (for those layouts based in hotter climes!) the first dust storm... Tone the gloss down, folks! ;) :)
Quote from: Hobby on December 08, 2019, 09:33
Good point about paint. It's one thing that shouts "toy train" to me is a gloss finish with gloss varnish on top! OK you may see the odd photos with a truly gloss finish in Real Life (usually outside the place it was built/rebuilt) but how long did that finish last? An hour or two until if rained (UK and Northern Europe) or (for those layouts based in hotter climes!) the first dust storm... Tone the gloss down, folks! ;) :)
I am a bit torn on this. I am collecting stock to build a modern day preservation line, but these are often only open a dozen times a year and the "hero" locos are immaculate so I need to model that without it looking like they have been given 64 coats of varnish.
The maintenance loco and rolling stock are fair game for weathering, so time for the airbrush.
Even immaculate preserved locos don't tend to have a deep varnish finish. They are varnished to preserve the paint but because of the size of the loco it doesn't look that bright and some parts won't be because of their use, the smokebox for instance. That's the trouble with the models which use a high gloss because they are so small they just look ridiculous...
Quote from: Hobby on December 08, 2019, 14:51
Even immaculate preserved locos don't tend to have a deep varnish finish. They are varnished to preserve the paint but because of the size of the loco it doesn't look that bright and some parts won't be because of their use, the smokebox for instance. That's the trouble with the models which use a high gloss because they are so small they just look ridiculous...
Agreed, any ideas how I could reproduce this level of shine?
(https://i.pinimg.com/originals/c9/90/dc/c990dcc5b71178ddaa03870c2fb6fdfd.jpg)
It has been mentioned before and is the only thing that really matters - it is your railway so model it as you wish.
Another aspect is consistency. I remember one large exhibition layout where the railway aspects and the scenery were subdued if not well weathered, but all the road vehicles were diecast, mint out of the box. The contrast was just so stark. That is not to say all aspects of the model must have the same level of either weatheredness or glossy newness but one approach is to work out the range of you find satisfying.
Also, it makes sense if the locos are modelled clean and bright is not to model the layout to represent a dull and dark day in a run-down environment but as a clear and bright late spring day in well-tended surroundings. That will tone down the colour and finish of the stock. The lighting can have a big effect too as well as the background, which is why shops put such a lot of effort into it.
Quote from: GraemeD on December 08, 2019, 15:27
Another aspect is consistency. I remember one large exhibition layout where the railway aspects and the scenery were subdued if not well weathered, but all the road vehicles were diecast, mint out of the box. The contrast was just so stark.
I agree, and its a dilemma. In reality the Locos on open days are cleaned to the point of obsession so are much brighter and cleaner, but a model would look unrealistic. It is like having a model of two shire horses all dressed up ready for the County Show, being used to pull a plough. Same horse, different situation, different result.
I bought a joblot of defect 3D-prints to find out, whether they meet my expectation. And I tend to agree, they leave something to be desired.
This was further to visiting an engineering exhibition and discussing 3D-printed parts: you can get 3D-printed metal parts with 98% material density and 80% strength of a machined part, e.g. a gear wheel that can take the load and has a surface finish ready for use, i.e. no polishing required. Obviously there is a price tag...
To say, the surface finish is also driven by the software and the print machine; evident, if you study the Shapeways catalogue!
To me, it appears that 3D-prints in a quality that matches plastic injection moulding, is more expensive than injection moulded model. It is possible, but not at a competitive price. I have some road vehicles from Arsenal M, and their 3D-print quality is at level par with plastic injection moulded vehicles, their price is about double!
I have the small machinery from Noch, which is 3D-printed, it's sort of okay, but screams 'REWORK' at you; the surfaces are not exciting.
I have the white metal engines (Deutz and DEMAG) from Mr Hauser, who designed the Noch models, definitely superior surface.
I will consider more models in 3D-print, but only when I can look closely at them before buying.
Personally, I want engine bodies in metal for better traction!
My thoughts
Waldschrat
Quote from: Leprechaun on December 08, 2019, 21:53
Personally, I want engine bodies in metal for better traction!
I agree, I was not impressed with my first venture and thought that it would have been quicker, cheaper, and given better results to scratch build in every case.
I certainly wouldn't want to try and make a loco look as good as injection molded,it would drive me insane, and as you say I like a bit of weight to get grip.
Quote from: Leprechaun on December 08, 2019, 21:53To me, it appears that 3D-prints in a quality that matches plastic injection moulding, is more expensive than injection moulded model. It is possible, but not at a competitive price.
That is true, but so far all the 3D printed locos I have bought have not been of a prototype that would justify someone producing a plastic kit so I am prepared to pay the price rather than scratchbuild stuff with some pretty complicated body shapes. A steam loco is usually fairly easy to reproduce but some of the diesel bodies have some "interesting" shapes! As usual horses for courses!
As regards weight, as mine are larger prototypes I can add weight inside the body but as Bachmann US's models of the Tallylyn locos prove for smaller locos a metal body is preferable.
That photo you posted Stephen would probably be best suited to a semi-matt finish in model form. I agree with Graeme that it's a persons own layout and so they can do what they want but I don't understand the need to use full gloss paint when there are suitable "toned down" alternative paints available. Ditto road vehicles. I'm sure someone did a thread somewhere on "scaling down" colour which explained it well but I can't remember where I saw it... At the end of the day the result can be the difference between making a toy train and a model railway...
Quote from: Hobby on December 09, 2019, 09:08
That photo you posted Stephen would probably be best suited to a semi-matt finish in model form. I agree with Graeme that it's a persons own layout and so they can do what they want but I don't understand the need to use full gloss paint when there are suitable "toned down" alternative paints available. Ditto road vehicles. I'm sure someone did a thread somewhere on "scaling down" colour which explained it well but I can't remember where I saw it... At the end of the day the result can be the difference between making a toy train and a model railway...
I read somewhere that a single coat of gloss at 00 scale is like having 76 coats of clear varnish on your prototype. For my SciFi work I used mainly Games Workshop paints and their Matt "Ardcoat" was pretty good at killing reflections. Unfortunately if overdone it can obscure some details so has to be used sparingly, but then their models are designed to be used as game pieces so a tough top coat is pretty useful.
I was given advice many years ago that he best way to get scale colour is to get the photo you want up on the screen (or photograph) get a piece of card with a hole punched it it and use that to cover up everything else to isolate a small circle of the actual colour you want match it to the Vallejo colour chart https://acrylicosvallejo.com/wp-content/uploads/2017/06/vallejo-model-color-CC070-Rev14.pdf (https://acrylicosvallejo.com/wp-content/uploads/2017/06/vallejo-model-color-CC070-Rev14.pdf)
It doesn't help reproduce shiny surfaces like that loco though :-)
Dear Hobby,
Yes, I fully agree, and it was the only reason for me to cough up the asking prices of Arsenal M; I was in the Civil Defence, and they produce some obscure models, e.g. Tempo Land Rover and Menck Schuerfkuebelraupe, that are extremely unlikely to appear as injection moulded model, but I absolutely wanted.
And that's where the strength of 3D-printing lies: prototypes and small number batches, where the cost for the expensive moulds would drive the price per piece to prohibitive levels. NPE does comparable models in injection moulding, and their price is 2,5 times higher!
You decide where to compromise: detailing and surface versus price. :laugh:
With regards to painting:
I recollect, we had extensive discussions and arguments over 35 years ago at university, and to prove the point I assembled some Rai Mo kits (some of which are all polystyrene plastic, some white metal and polystyrene), and painted them to match the (then new) Trix Bavarian range. It proved that you can achieve a paint quality to match commercial products even with waterslides. It also proved that you can't identify the base material through the paint job, if that job is done well. I used semi-gloss clear varnish ex spray can thinly, and the finish was exactly as Trix's.
However, 15 years later that varnish had yellowed, or rather browned, and that showed even the slightest thickness variations of the coat! No, they weren't exposed much to sunlight.
Redone with a spray-gun and top of the range varnish from Tamiya.
Cheers
Waldschrat
Quote from: Stephen Rainsbury on December 09, 2019, 21:04
I read somewhere that a single coat of gloss at 00 scale is like having 76 coats of clear varnish on your prototype.
I've sometimes wondered how that observation came about and why it is used?
In one respect it is literally true (or more precisely a single coat is like 76.2 coats, or 87 if it happens to be HO), though assume that is not what is implied. That is possibly taken in conjunction with information that achieving a high gloss on railway carriages requires several coats (and rubbing down in between), or so I understand. Then given that glossy models tend to look more glossy compared to the real thing and putting two and two together to get five leads to the assumption that the varnish thickness is the key. (I think that is what is known as of the logical fallacy of confirming the antecedent.)
I suspect the reason has something to do with the scale and things like the smallness of radius of curvature of things like boilers and the viewer being able to change viewpoint almost instantaneously by the equivalent of many tens of metres and so see a whole raft of different specular reflections. In more practical terms, a gloss finish shows up every surface imperfection and paint nib as a glint, making the model look more like a toy.
There is one part of a model that I really do think looks best shiny and bright and that is real polished brass steam domes. My attempts at painting with brass-coloured paint looks lame.
A high gloss finish can make anything look like a toy! ;D
(https://www.wrapvehicles.co.uk/assets/img/dyn/3650c940x375.jpg)
The photo actually looks better than any I've seen on the road, perhaps because you can actually see reflections of things and not just a shiny golden blob whizzing past.
Then there is the opposite:
(https://images.cdn.circlesix.co/image/1/700/0/uploads/posts/2017/05/5d659eb81b00a91f922083b12da62de9.jpg)
Perhaps because weathered models are quite common, it just looks like a really badly weathered model to me.
With that second one I think the problem is that the rust is not where it should be if it formed naturally so it looks wrong... As you say someone has got out their weathering kit (brown spray can) and just done it at random without looking at real rust and where it forms.
Of course, that reasoning regarding varnish thickness assumes you use the same varnish (and paints) on both, which would not be a good idea...
One aspect of any paint job are viscosity and surface tension, which you can't scale; the reason why real water on a model railway hardly ever looks realistic, especially, when flowing.
On the real deal you're not too worried about viscosity and surface tension, as long as you get an even finish. However, they are carefully designed parameters of any good quality paint! When it comes to corners and edges, they tend to be radiused to prevent injury, and where paints 'fill' corners and round edges, it normally doesn't matter. Scale that radius down and it becomes a sharp edge. but your paint will still 'fill' the corner and radius at the edge as the viscosity in combination with the surface tension 'pulls' around the edge.
The other aspect is that the 'glossiness' changes with viewing distance, i.e. the further the less gloss something looks. Mentally we compensate the effect as we're used to that, but this compensation is not scalable either, i.e. as we typically are much nearer to our models they appear too gloss, especially when surveying the realm!
By the bye, that golden car will be confiscated in most European countries as it is a danger to road traffic; other road users might get blinded by sun or light reflections in the paint job! That paint job makes it an MOT-failure in a lot of countries.
Cheers
Waldschrat
I think regarding paint finish on models we should look to the way the ready to run manufactures do it.
They have the resources to have any finish on their locos and rolling stock they like, yet they go for a satin finish in almost every case.
It is just my oppinion but in 009 I think satin or matt finish always looks better than gloss on 009 models.
Brian Meldon
But they don't cover up the sandpaper finish on some 3D prints half as well as a thick layer of gloss enamel put on with a wallpaper brush, Brian! ;)
Quote from: B.Meldon on December 13, 2019, 10:01
It is just my oppinion but in 009 I think satin or matt finish always looks better than gloss on 009 models.
Strangely enough I have just dug out some old plastic tank bodies left over from an old project (the turrets were use on a space station model) and was going to experiment with spraying them different colours and different finishes to see what looks best at that scale.
I currently 4 cans of Varnish to try, 3 from Games workshop, and one B&Q brand satin, they are all good, but you can't put n more than two coats of a light dusting before you start to obscure details.
It doesn't help watching the two train series currently on TV and seeing the side of their locos shinier than a spiv's suit.
Stephen
Quote from: Hobby on December 13, 2019, 10:11
But they don't cover up the sandpaper finish on some 3D prints half as well as a thick layer of gloss enamel put on with a wallpaper brush, Brian! ;)
Which takes us back to the reason for the original post :-)
Going back to basics, on the real thing you would use:
1. A primer with corrosion protection on steel or similar, or an etch-primer on aluminium and galvanised steel. Paint doesn't stick well to zinc, that needs either weathering for 2 years at least, or an etch-primer. You can read that across to ZAMAK.
2. Then you would use a filler in 1 to 5 layers to cover up blemishes, which would do nicely for those rough 3D-print surfaces; if it weren't for the fact it'll cover up any detail.
3. For lushness of the colour you would apply a white top-coat now (except for black finishes) in 1 or 2 layers.
4. Then it's time for the final colour, typically in at least 2 coats.
5. To finish off you also may apply a clear coat or 5 to improve colour intensity.
Noting that today for top-class finishes you use a composite resin coat.
Problem is: you can't do that on a model, all detail would be lost, even without filler.
Conclusion: You can't match the colour of the real thing properly, somewhere along the way you have to compromise.
So yes, copying what we accept and like, i.e. from the manufacturers' is certainly the way to go. However, some of the paint layers listed above are there for a purpose, ignore that at your peril:
1. You need a primer to get the paint to properly stick to the surface, for most plastic materials, brass, copper and zinc-alloys an etch-primer is the weapon of choice. Make it a white or pale grey one to help with the lushness of the final colour.
2. You need your colour paint, obviously.
3. you may need now a high-gloss varnish for the decals to adhere well and become invisible after the last coat.
4. and you need your varnish to protect your decals and lining job.
As already discussed, semi-gloss or matt finish tends to look better than gloss, and thinner is the mantra. ;D
Just the little bit I know about painting fences, cars, lorries, and boats. ;) And no, I don't use Ronseal etc. for a reason.
Waldschrat
I can only speak from my own experience, but I have never used any form of primer on the models I build.
I have always found that the paint works just fine provided the surface is de-greased.
I have used Humbrol and other makes of enamels, and in more recent years Tamiya acrylics as well, all applied with a brush. I also use Halfords satin black acrylic rattle cans.
These have been applied to plastics, tin, steel, brass and other materials, some on the same model and I have never had any problems with the paint not adhering to the surfaces.
That said the surface finish has to be made nice and smooth before painting.
I usually try and stay clear of 3d printed items as for me the surface finish is usually poor, requiring quite a lot of work before painting, far more so than with other materials.
I am not saying this is what everyone should do as other get good results using primer, it is just what I do.
One major benefit with using a primer such as the ubiquitous Halfords Grey Car Primer is that it is very good at showing up any blemishes before applying the top coat.
Dear Brian,
I've done that too, mostly in my younger days, and it works okay; 45 years hence I still have some models where the paint is okay. But the paint job isn't, as I wasn't experienced then. After doing my tour of duty in a garage with a truck-size paint workshop I now practically always use primer. I find it makes the top-coat spread more evenly, to say you get away with a thinner coat. If I skip the primer, as you do on a rush job, I can see its inferior finish. ;D
Cheers
Waldschrat
During my SciFi days I always used a primer, it somehow brings the model together and gives a good base to start from. I used White for figures, as it gave better skin tones, Grey for aircraft and vehicles, and Brown for natural scenes.
The only problem this time of year is that unless I pre-heat the garage sprays give a nasty mottled finish.
Did I say 'paint-workshop', or didn't I? ;) In winter everybody came into the paint workshop because it was nice (as in dust-free) and warm! :D
Down in the pit under the trucks you froze not just the brass balls of the monkeys...
Of course, a bit of diurnal cycling during drying is one way to ruin a paint job. :P
Merry Christmas
Waldschrat
Quote from: Leprechaun on December 16, 2019, 17:23
Did I say 'paint-workshop', or didn't I? ;)
The point was duly noted, I was comparing the lives of us mere mortals to your absolute luxury :laugh:
My 40 year old 2KW "Redring" fan heater does a Stirling job if you point it straight into my paint booth (large cardboard box) for 20 minutes before you start, and leave it on for 20 minutes after. So two coats with ten minutes between and that's and hour, which of course I can watch racking up the digits on our smart meter :-[
Apologies, that paint-workshop wasn't mine and was almost 40years ago, when as a student I had to work to accomplish the mandated work experience. :D
Today my level of luxury is at level par with yours, but understanding why a garage would 'pre-heat' a full size lorry for 48hrs before spraying and keep it warm for 48hrs afterwards (which costs a small fortune), I don't expose models to temperature change until the paint is dry, as in fully dry. ;)
Not sure whether your 20min is enough? ???
Painting in summer helps, or not?
Cheers
Waldschrat
Quote from: Leprechaun on December 17, 2019, 20:16
Not sure whether your 20min is enough? ???
Painting in summer helps, or not?
I haven't noticed an issue, but in fairness I keep spray cans indoors for 24 hours, its a trek round the garden to get into the garage, plus the door is double locked so if the weather is bad I tend to give it a miss anyway or I am soaked before I even get started.
My SciFi stuff always turned out OK, but then it was normally only undercoat. I haven't sprayed any railway stuff yet, so will keep an eye out.
Stephen