Best primer for 3D printed ;pco

[Tim Parsonson]

I'm just about to get my first 3D printed loco body and have been reading  bit about finishing. Suggestions are that a filler primer is best, with Krylon and Montana suggested.

Does anyone have any experience with either of these, or any other suggestions?

[Hobby]

It rather depends on the quality of the print. If I use one of Shapeways better quality prints the last thing I'd use is a "filler" primer as any added filler will hide the detail. In the early days of 3D prints I did try one of the "filler" type primers but I didn't find it worked particularly well, you are best off doing the "smoothing" and filling work first and then just using an ordinary car primer (Halfords seems to work better than the cheapo stuff)...

A light spray of grey primer after cleaning will show any flaws in the print which need attention though.

[B.Meldon]

I never use primer!

Perhaps I am just lucky, but I have never had any issues with paint not adhering to surfaces on models.
I just make sure the surface has the best finish possible and is de-greased before painting.

[Hobby]

One of the main advantages of using a primer, as I mentioned, is that it highlights any flaws in the model before you add the top coat... Perhaps your models are perfect already, Brian, but mine aren't so I'd rather get the imperfections sorted before the painting proper!

[B.Meldon]

One of the main advantages of using a primer, as I mentioned, is that it highlights any flaws in the model before you add the top coat... Perhaps your models are perfect already, Brian, but mine aren't so I'd rather get the imperfections sorted before the painting proper!

Err.. no they are not perfect, but perhaps they are good enough for me!

[garrywhiting]

Before using a primer & depending on the quality of the print I first use the Japanese product "Mr Surfacer" --- this comes either as an aerosol spray or as  brush applied. A number of different grades are available, if using the liquid version you will also need some cellulose thinner to clean your brush afterwards.  There are UK suppliers of the product.

For priming I generally use Halfords aerosol spray , although I have also used Wilko grey primer.

I have white, red oxide & grey primers from Halfords.  Primer choice is determined by the final top coat paint scheme,

If final top coat is white, cream or yellow --- use white primer.
If final top coat is red or brown ---- use red oxide primer.
If final top coat is green or blue ---- use grey primer,
If in doubt --- use grey primer.

Best is to experiment & discover what works for you.  We all have our preferred techniques, developed over the years, so it's each to their own really.

Garry

[Tim Parsonson]

Thanks everyone, I guess you've just saved  me some money and trouble.
I will experiment as you suggest.