How to paint engine parts?

[SunDevil1981]

Hello to all,

I am new to this forum, but not new to car modeling. I used to do some car modeling during my younger years. Due to lack of time and other interests I lost touch until I noticed the Formula 1 models form Tamiya. I bought myself the Mclaren MP4/6 (1:12) And The Williams FW13B (1:20). Again due to lack of time and so on I put these models in the attic and concerned selling them. As many things in life continuesly change the passion for car modeling caught me again and this I do not intend to loose it anymore and want to take my time building these two models and am considering buying even more.

That being said I searched the Internet for tips, tricks, pics and further inspiration since I would really like to build these models with much detail...so I found this forum and lots of beautiful posts!

A lot of questions popped to my mind also though...some of them were answered in the wonderful How-To's, like the washing technique and so on. Unfortunately the pictures in the Engine Plumbing thread are missing and I also like to know how to paint the engine and its parts at best. Can anyone help me out with that? Maybe I have overseen a thread or some links where this is explained nicely?

My questions:
The Engine Parts:
Do I use primer and why?
Do and how should I sand the engine parts, they are so small sometimes?
Can somebody put new pictures in the engine plumbing thread?
Where do I get detailed parts for the FW13B?

Many thanks in advance,
Peter

[MPWR]

You do not need primer on engine parts (unless you plan to use some super hot nasty volatile lacquer that will dissolve the plastic if unprotected). Wash them to remove demolding agents, but otherwise parts are ready to paint after you have cut them off of the sprues.

The reason not to use primer on detailed parts like engines is that primer nearly always needs to be sanded. On very complicated shapes, this becomes impractical or impossible.

Primer is used to create a perfect substrate for painting bodies. It also can protect plastic from solvents in body paint. But I certainly don't use it anywhere else- engines, interiors, suspensions, etc.


As for engine wiring pics, search the internet for images of the engine you're building. Pics of a small inline 4 Honda engine would not do you a lot of good in creating a V10 F1 engine. What is visible (ignition wires, coolant hoses, fuel lines, telemetry cables), and what isn't? Engines are all different- so find some good images, and make what you are building match what you see.

[SunDevil1981]

Originally Posted by MPWR

You do not need primer on engine parts (unless you plan to use some super hot nasty volatile lacquer that will dissolve the plastic if unprotected). Wash them to remove demolding agents, but otherwise parts are ready to paint after you have cut them off of the sprues.

The reason not to use primer on detailed parts like engines is that primer nearly always needs to be sanded. On very complicated shapes, this becomes impractical or impossible.

Primer is used to create a perfect substrate for painting bodies. It also can protect plastic from solvents in body paint. But I certainly don't use it anywhere else- engines, interiors, suspensions, etc.

Many thanks! But why do I see people primer parts like the brake disks?? And do I rather spray paint (or airbrush) the engine and the small parts or simply with a brush?

Btw. I haven't found many pictures of this engine yet...

[Kjenjak]

Originally Posted by SunDevil1981

Many thanks! But why do I see people primer parts like the brake disks?? And do I rather spray paint (or airbrush) the engine and the small parts or simply with a brush?

Btw. I haven't found many pictures of this engine yet...

You can prime other plastic parts than the body, but you don't have to. In my experience the primer helps the paint to stick better to the part and to distribute evenly accross the painted surface. Maybe try for yourself. Use primer on some parts, then paint the primed parts and some non-primed and see what works best for you.

A disadvantage of primer is, when you have to work on a painted part and have to cut of bits or scrape away some paint, the grey undercoat will show.
And be aware that primer will flatten the result of your paint job if not sanded. This could be helpful if you want to achieve a super flat surface.

Priming of other materials like metal (photoetched parts) is a must, I have never managed to paint a "raw" metal surface in a satisfying way.

Spray/airbrush gives a cleaner result, and is imo easier when done on many parts at once or on complex parts. Brush is cheaper and faster for single parts and details.
When brush-painting, primer won't be necessary that much, since you don't get such an even distribution of the paint anyway.

[MPWR]

Originally Posted by SunDevil1981

But why do I see people primer parts like the brake disks??

I have no idea.

The usual reasons to use primer are:

1- Adhesion- to help paint stick to the plastic. But most hobby paint goes onto plastic pretty well.

2- Background color. If you have a part molded in red and want to paint it white, painting it grey first may help so that the red doesn't show through.

3- To protect the plastic from solvents. If you are using real car paint on a plastic model car body, you must do this

4- To prepare a perfect, flawless substrate for body painting. Primer, together with time, patience, and fine sandpaper, are a good way to do this.


Like Kjenjak says, try it yourself. Do some parts with, and some without. See if one way is easier, and one way gives better results. I have certainly done this- and so now I prime nothing but bodies. I find that it adds nothing in other places, but perhaps you will like it.


I airbrush everything I can on a model- which is usually about 95% of it. I use brush painting usually for small details, for areas that won't be well seen, or places that are impractical to mask for spraying.

[SunDevil1981]

Many thanks for the wonderful info's! So I will do some experiments and get my own experiences.

I will use the Tamiya acrylic colors and will try to air-brush a much as I can (I thought so that this would be the best option).

Two questions:
- which primer to use? Tamiya primer ok?
- where to get super-details part for the Williams FW13B

Many many thanks! I already love this forum!

[Kjenjak]

Originally Posted by SunDevil1981

- which primer to use? Tamiya primer ok?

I always use Tamiye fine grey or white primer on plastic parts, works great! Except on resin parts, I don't know why I can't get this to work!
For metal (photo-etch) you should use a special metal primer.

[KC27]

Depends what you're spraying.

From the can I use Tamiya grey or Halfords white primer when painting with Tamiya sprays as the main coat.

If you're airbrushing Tamiya acrylics, I do this over Vallejo primer and find it is great. Really easy to work with and clean up.

And don't forget to use your dust mask when sanding and a respirator + ventilation when airbrushing/spraying.

KC

[MPWR]

Tamiya acrylics are easy and forgiving to spray. Use Tamiya's acrylic thinner for spraying, but clean the airbrush with glass cleaner. Also glass cleaner can be used to easily strip the paint, if you are not so happy with the results and want to try again.

Tamiya primer is great stuff. To make it spray even better, warm the spray can in hot water for 5-10 min before spraying. But make sure the spray nozzle is dry of water before using.

What additional detail parts do you think the kit needs?

[John18d]

SunDevil - please pay close attention to KC "Kieran" and his safety warnings about respirator mask and ventilation - you do not want to get COPD or die for your hobby
John

[John18d]

SunDevil - also do a search here on this forum for the MP4/6 1/12 kit - there are several that have been done and KC is doing one at this time
Also you can "google" Bil Atteridge and you will find his beautiful MP4/6 on the internet
Hope that gives you some ideas

Primer - yes always - it does what the guys have said above - I use strictly Tamiya fine white and grey primer on plastic and I use the Tamiya etching primer on metal - you do not have to sand the Tamiya primer. Just apply light coats

John

[SunDevil1981]

Originally Posted by MPWR

Tamiya acrylics are easy and forgiving to spray. Use Tamiya's acrylic thinner for spraying, but clean the airbrush with glass cleaner. Also glass cleaner can be used to easily strip the paint, if you are not so happy with the results and want to try again.

What additional detail parts do you think the kit needs?

What do you mean with "use Tamiya's acrylic thinner for spraying"?

I was looking for a seat belt set and carbon fiber decals...but I already found them on eBay.

Many thanks!

[SunDevil1981]

Originally Posted by John18d

SunDevil - also do a search here on this forum for the MP4/6 1/12 kit - there are several that have been done and KC is doing one at this time
Also you can "google" Bil Atteridge and you will find his beautiful MP4/6 on the internet
Hope that gives you some ideas

Primer - yes always - it does what the guys have said above - I use strictly Tamiya fine white and grey primer on plastic and I use the Tamiya etching primer on metal - you do not have to sand the Tamiya primer. Just apply light coats

John

Many thanks!

"Primer - yes always - ..." ?!?! Only on body parts right?!

[John18d]

Primer - YES - on all the plastic parts including engine - transmission - suspension .

I Primer everything in light coats that I want to paint - if you use the Tamiya primer - there is very little "talc" in it so there is no need to sand it if you apply thin light coats.

If you are using an automotive primer then you would want to use Primer "sealer" NOT primer "filler" for applying under paint

John

[MPWR]

Originally Posted by SunDevil1981

What do you mean with "use Tamiya's acrylic thinner for spraying"?

Use this stuff to thin the paint when you are preparing to spray it.



Most hobby paints (including Tamiya acrylics) are much too thick to spray through an airbrush straight out of the bottle. They need to be thinned/cut/reduced so that they flow better. Tamiya acrylics are water based- so in theory they can be thinned with water. However they perform best when thinned with Tamiya's acrylic thinner.

To clean the airbrush after spraying, using Tamiya's thinner is unnecessary. I use a spray bottle of glass cleaner for this.


As for primer on all parts, again try it yourself and see. It is entirely unnecessary- but if you like the results better when you prime everything, you can certainly do it that way. When it goes on well, Tamiya primer has little texture. But when it goes on poorly, it must be sanded or stripped before painting. I never spray it on anything that I am not planning to sand fully before painting, but your results may be different. On most parts, I get better results by not using it. (It is also faster and cheaper not to use it- making it a rare case of better, faster, and cheaper.)