Custom decals/printing: where to start?

[TeddytheSpoon]

I'm approaching the finish line with a LEGO train design of an LMS Ivatt 2-6-2T 2MT - just waiting for Breckland Bricks to re-open so I can ask about custom wheels. But having built most of it in the brick already, I'm starting to wonder if I should add some custom bits for the livery too.

Does anyone here have good resources for how to get started on this? I've considered having some parts printed, but wondering if decals might be a better option for price and re-usability of the parts. (It's mostly tiles that would need doing, at least for this one.) I don't really know much about what process is best or how to do it though!

[JopieK]

The best way is to use vinyl. But it is tricky and costly (at least at low amounts).

[Hod Carrier]

I always think that if you're building a model of something real it would be good to include at least some of the more obvious markings and other decorations. How far down this particular "rabbit hole" you want to fall is entirely up to you, but I do think that a loco should have it's number and the railway's identifying crest/logo. Printing onto bricks is the Rolls Royce solution for getting logos, numbers and other decoration onto parts, but it is permanent and a bit pricey. May I recommend a couple of alternatives...?

An option that I've made use of is printing my own graphics at home and then applying them to the finished model. Design and scale them on your computer and then print them onto self-adhesive inkjet vinyl (available in A4 sheets of white or transparent from retailers such as this one). Just a couple of tips with this technique. Leave the sheets for a few minutes after printing to dry before handling and then seal the print with some spray-on craft sealer before cutting and sticking. As well as the sealer you should also get a selection of Sharpies in different colours, as the white edge of the stickers will still be visible and may need to be coloured-in before applying them to the model. If you want to try to match your stickers to the colour of LEGO bricks, Rebrickable has this useful guide giving you the RGB code for each colour, although bear in mind that there can be quite a bit of colour variation between individual parts of the same colour and that your printer may not necessarily replicate the desired colour perfectly.

The other option is to use waterslide transfers. Most LEGO train models are tolerably close to UK 7mm scale/O-gauge (a scale of 1:43.5) and you can buy sheets of crests, numbers, markings and lining that you can apply directly to your model. For British models, like your Ivatt 2MT, a retailer like Fox Transfers should be able to provide all your needs.

Hope this helps.

[Karle]

Can the RBG code be used to mix paint?

[zephyr1934]

6 hours ago, Hod Carrier said:

An option that I've made use of is printing my own graphics at home and then applying them to the finished model. Design and scale them on your computer and then print them onto self-adhesive inkjet vinyl (available in A4 sheets of white or transparent from retailers such as this one).

Printing on transparent usually does not work well for at home printing unless you are printing dark (e.g., black print will almost always work). If you want to go lighter than the brick, then you will want the opaque white background.

Another option is to just print on white paper, you can probably find a copy shop with high quality color printers (e.g., the FedEx store here in the US). Then cover the paper with transparent packing tape to give it a nice glossy look and cut to size. As Hod Carrier said, use colored markers to cover the white edge of the paper.

[TeddytheSpoon]

On 9/15/2025 at 9:34 PM, Hod Carrier said:

[snip]

That's very useful, thanks! That's more or less my thinking for a few crucial details - running number, plus either BR crest or LMS lettering. Somehow I hadn't thought about looking for existing transfers for model trains... I'm actually building at a slightly unusual scale of 1:64 (ish) but I might still be able to find something.

[JopieK]

On 9/15/2025 at 11:46 PM, Karle said:

Can the RBG code be used to mix paint?

Printing inks are not RGB, but CMYK possibly even more so-called spot colors (including white for transparent stickers etc).

[Karle]

2 minutes ago, JopieK said:

Printing inks are not RGB, but CMYK possibly even more so-called spot colors (including white for transparent stickers etc).

I this case I'm interested in using the codes for custom paint mixing.  For water slide decals for American prototype 8-wide rolling stock and locomotives look at K-4, Protocraft or Micro Scale decals.  OK Brickworks did excellent custom stickers at one time...

[JopieK]

It just doesn't work like that: it is virtually impossible to get it "first things right" the actual ink, the decal material, the background color (i.e. the color of the bricks), everything matters. I would suggest you use an iterative approach, try out how it looks, adjust, and that over and over again till it is acceptable to you.