Painting N scale cars in FXD build thread

[dougnelson]

Hi Josh:
I am a bit disappointed with the roughness in that FXD.  The results do not seem to be consistent.  I think I would ask Shapeways to try to do better.    Here is a recent FXD I had printed (also from Rapidpro):



Seems like the results vary below the belt line.  Above the belt line is pretty good.  On mine, the paint hid most of the roughness:

[peteski]

Hi Josh:
I am a bit disappointed with the roughness in that FXD.  The results do not seem to be consistent.  I think I would ask Shapeways to try to do better.    Here is a recent FXD I had printed (also from Rapidpro):



Seems like the results vary below the belt line.  Above the belt line is pretty good.  On mine, the paint hid most of the roughness:

Doug, this is how the 3D printing works.  If the object being printed protrudes above the lower printed areas then wax gets printed/deposited to support those protruding areas. That is why the top of the model looks smooth and anything below the belt lines (and the side window glass) has the telltale signs of being in contact with the support wax.  In your example they probably picked the best possible print orientation. 

Another way to look at where the wax would be is to shine light directly over the top of the model. Anywhere you see shadows, wax will be printed (and the model surface will be rough in those areas).

[Chris333]

We need them to print without wax. The way everything is piled up in the 3D box to print there should be wax everywhere. The car probably had stuff stacked above it

[peteski]

We need them to print without wax. The way everything is piled up in the 3D box to print there should be wax everywhere. The car probably had stuff stacked above it

Most of the 3-D printed FUD items I receive from Shapeways seem to have a wax-free side as if they were on top of the print table.  I really don't think they print multiple overlapping layers of items.

[Mark5]

Doug, wow man that is kinda rough.

Still a bit too rough for my taste - maybe by the time my layout gets going again it'll improve.

Mark

[Chris333]

I guess they do it in a single layer tray. I thought it was a cube.

[Dave Schneider]

The more things change, the more they stay the same. Doug, welcome to the non-exclusive club of those of disappointed 3D printing customers. I exaggerate a bit, but I have yet to receive anything that makes me say Wow! It's not that it can't be done, it's just that most of us are that wealthy. Its frustrating because the 3D design is really good, but the printing process lags behind.

Best wishes, Dave

[peteski]

Ok. So, since I have 2 cars and 2 more on the way, I'll let this one be and finish it as is.
@peteski I think I want to see how perfect I can take this.  Something as small as this I feel like I can manage sanding between coats.
Ever since my early days as a modeler, I've struggled with exterior glossy car bodies. I've never been able to figure it out.
What's the secret? What's the formula?
Do I get this stuff and sand between coats?
http://www.micromark.com/micro-mesh-finishing-kit,7601.html

So far, I've been using 600 grit on this model.

Secret? Formula?  I think every modeler does it slightly different.  The size of a model also makes a difference.

On larger scale models (from 1:43 all the way up to 1:6 scale) my formula is to start with as smooth as possible unpainted surface and to use as few paint layers as possible.  On most plastic (stock-built) models I don't even use primer!  I just shoot the gloss enamel or plastic-compatible lacquer right over bare plastic.  I guess I figured out the right combination of paint viscosity, air pressure, nozzle opening, and a distance between the airbrush and model to achieve glossy finish. I never sand, or rub-out the paint either.  I find the gloss finish to be good enough as-is. If I had to spend hours sanding or rubbing-out paint I would find another hobby.  My paint jobs are good enough for me to place in the top tiers of many model contests, so I guess the paint finish is good enough for the judges.    There were few times I had to sand and rub-out the paint when a piece of schmutz got stuck in it when still wet.  But that is the only time I ever did that (and I was not really keen on doing it).

Some modelers paint their models with dozen layers of paint and clear sanding between them. I would shoot myself if I painted like that!  Not only this type of finishing takes many hours of painting and rubbing the paint out, it takes days or weeks to complete.  It also usually leave the model with a layer of paint so thick that it looks like it was dipped in honey!  But it sure is shiny! 

On a model as small as N scale car, (not 3-D printed) I use the same  method as on the larger models but I also lower my expectations. The fire engine model (on which John commented about having orange peel) I was quite happy with the results.   That is a brass model with Scalecoat II ATSF Warbonnet Red over bare brass, then decals then a layer of Glosscote.  So the paint is very thin (leaving all the fine details crisp).

So it is up to you how far you want to take this. I also mentioned earlier that I like glossy finish on N scale cars which would have been glossy in 1:1 scale. But to be honest, since this thing will be displayed near that wicked-dull truck, maybe the gloss should be toned down a bit.   I think that a final coat of 60% Glosscote, 40% Dullcote, and lacquer thinner would give you the semi-gloss finish.  I use that mixture as a final coat on my N scale boxcars and locos.  But spray that before doing the chrome paint.

[daniel_leavitt2000]

You gotta think that gloss scales down too.

This. So much this.

It also helps with light refraction on extreme macro shots where any lights or reflections cause a halo effect.

[chicken45]

Thanks, everyone! Tempered expectations are important.

Can Microscale Micro Flat be mixed with Future?

[peteski]

Thanks, everyone! Tempered expectations are important.

Can Microscale Micro Flat be mixed with Future?

Never tried it. I am not a big Future user (I used it once to dip a car windshield in it).  You don't like stinky Dullcote stuff?  I love it!  Microscale Flat is alcohol based and I'm not sure what Future's solvent is. Probably water with ammonia - or maybe diethylene glycol.  Going by the smell Future does not seem to have alcohol in it. 

[chicken45]

Never tried it. I am not a big Future user (I used it once to dip a car windshield in it).  You don't like stinky Dullcote stuff?  I love it!  Microscale Flat is alcohol based and I'm not sure what Future's solvent is. Probably water with ammonia - or maybe diethylene glycol.  Going by the smell Future does not seem to have alcohol in it. 

It's more of what I have on hand right now. I have a can of dullcoat, a bottle of acrylic gloss, Future, and the Microscale Flat.

[Wutter]

Can Microscale Micro Flat be mixed with Future?

I haven't tried Micro Flat in Future, but I use Future for basically all of my final finishes. When I want anything from a satin to a dead flat finish, I mix in Tamiya X-21 Flat Base and it works really well.