Tools of the Trade - Part 4: Finishing

19 Aug 2021
Welcome back to our Tools of the Trade series. This article is part 4 in the series. If you missed parts 1 through 3, check them out here:
This series is designed to get you equipped to start 3D printing your own model car and truck parts quickly and as inexpensively as possible.
Let's save you money!
In this series, I outline everything you need to get started 3D printing your own model car and truck parts with a resin SLA 3D printer. I share with you the tools and materials that I use personally in my successful 3D printed parts business. Where there are free or cheap alternatives, I point those out, and where there are dedicated tools for a certain purpose that are more expensive, I share those too so that you can see all of your options. In some of these cases, the expensive object may make life a lot easier, but in general I think you will see that you can start 3D printing for your model car builds for less money than you might think!
Please note: links to products in this article may be affiliate links. This means that when you purchase an item from an affiliate link, you pay the same price you normally would but I earn a small commission. My goal is to bring you accurate and helpful content, therefore I only recommend products that I myself have used and stand by. If I mention a product that I do not have experience with, I will clearly state that.
 
As an Amazon Associate I earn from qualifying purchases.
Many of the products listed in this article are available at fine hobby stores. If you are lucky enough to still have a Local Hobby Shop near you, definitely support them if possible instead of buying online.
Part 4: Finishing
Time to let your modeling skills shine!
  • In part 1, we looked at what you need to print safely and keep your space clean and organized. Part 2 was devoted to tools used in resin handling. In Part 3, I covered the equipment needed for post-processing your prints, from cleaning and drying to doing the final post-cure.
     
    Once these steps are complete, you have parts that are now ready to be finished and added to your model. This is where you will find yourself using many skills and tools that you are probably already familiar with.
     
    Once you are at this stage, working with your printed parts will be very similar to working with styrene model parts, with a couple key differences:
     
-First is safety: RESIN DUST IS HARMFUL, any time you are sanding resin parts, wear a dust mask, ventilator, or do so outside.

 

-Second, even though the proprietary resin blend you will learn how to make as a Scale Speed Garage member is more durable than standard resins, resin can still be prone to breakage. Therefore, cut and drill gently and slowly. When drilling, use a step bit or drill a small pilot hole first. For best results cutting 3D Printed resin model car parts, use a razor saw blade.

Finishing/Sanding Tools
  • Sanding Stick set: Perfect for light sanding to remove support marks and layer lines, these sanding sticks offer precision and control. Multiple grit options allow you to always have the right tool at hand


    Cheap/Free Alternative: See nail file option below

    Order now:

  • Nail File/ Emery Board set: These inexpensive nail files offer an assortment of grits at a low price. Perfect for sanding larger areas, but don't offer the precision control of the detail sanding sticks above.

     

    Cheap/Free Alternative: None, but you likely already have similar sanding tools in your modeling tool box.

     

    Order now:

  • Fiberglass Sanding Pens: Great for sanding tight areas where sanding sticks won't reach. This set offers 3 different sizes.


    Cheap/Free Alternative: You can often scrape hard-to-reach areas with the tip of a hobby knife blade, just be careful to avoid gouging the part.

    Order now:

Touch Up and Painting
  • Paint Brushes: A must for the model builder, a good paint brush set will offer an assortment of sizes and tip shapes. These are not only handy for painting details on your 3D printed model car and truck parts, but they're also useful for filling surface blemishes, cracks and other imperfections:
     
    One excellent method for filling support dimples, cracks, and other surface imperfections in your 3D Printed parts is to brush on some liquid resin and cure it with a UV torch (see below) and then sand it smooth. Think of it like an instant body filler.
     


    Cheap/Free Alternative: None. But as a modeler, you probably already have paint brushes around.

    Order now:

  • UV Torch: Use in combination with a brush and liquid resin to fill surface imperfections and cracks as well as a method for joining resin 3D Printed model car and truck parts.
     
    Simply brush on a small amount of resin, then use the UV torch to cure the resin in under 5 seconds. Then, sand as necessary.
     
    Be sure to select a torch such as this one, that has a wavelength range that includes 405 nm.
     


    Cheap/Free Alternative: Sunlight (maybe). Theoretically you could do this method using the sunlight, but you would have to brush on the resin away from the sunlight and then take the part out into the sun, by which point the resin will likely have dripped and/or ran off of the area you applied it to.

    Grab one here

  • Tamiya Fine Primer: This primer is an excellent all-purpose primer that applies in light coats, preserving fine details. This primer is lacquer-based and therefore is a suitable undercoat for all paint types.
     


    Cheap/Free Alternative: Many other spray paint primers will work well if used properly. Spray paint brands are one of the most hotly-debated topics in the modeling community, and everyone has different opinions and experiences. I won't weigh in on that here, except to say we've had great success with a number of different paint brands and types by always making sure to prepare our surfaces well and paint in light coats.

    Pick some up here

  • Light Scratch Filler Primer: Ideal for smoothing prints where layer lines are visible. Make sure to choose a filler primer such as this one that is designed for light scratches -others may apply too heavily and bury details.
     


    Cheap/Free Alternative: Filler putty can also be used for this purpose, something you may already have in your modeling tool kit.

    Order now:

Glues
  • BSI Super Glues: There's no better super glue on the market for the model builder than BSI Super Glues. We love this set because it comes with 3 different viscosities of glue (each with their own curing times), plus an accelerator, a de-bonder, and precision applicators.
     


    Cheap/Free Alternative: Any other super glue or cyanoacrylate will work, you just may not have consistent cure times or precision application. We've also found cheap super glues tend to fog certain finishes and plastics.

    Order now:

  • 2 Part Epoxy: For small, and or delicate joints where super glue may not provide enough adhesion, we love this fast-curing 2-part epoxy also from BSI.
     


    Cheap/Free Alternative: Other 2-part epoxies may work just fine, but in BSI's product we have found a consistent, high-quality product and have never strayed.

    Order now:

It's Time to Get Printing!
Thank you for reading this article series. By now, you should have a solid checklist for everything you need to begin your 3D Printing journey! This series distills many of the tricks, tips and tools I have discovered having printed thousands of model car and truck parts.
 
We know that this series is just a beginning. 3D Printing can have a steep learning curve, and it's not always easy to find reliable information on how to get started 3D Printing for your model car and truck builds.
 
That is why we built Scale Speed Garage! We look forward to walking alongside you as you learn how to harness the awesome modeling horsepower that 3D Printing offers.
 
As a Scale Speed Garage member, you will receive instant access to:
  • Our ever-expanding library of video tutorials and articles like this one to get you printing fast.
  • Troubleshooting help for when problems arise
  • Rotating monthly offerings of 3D-printable files, ready to slice and send to your printer.
  • A file request channel. Scale Speed Garage members dictate what parts we develop for download.
  • Printer and product reviews as well as notifications when products go on sale.
  • A weekly live video hangout to get troubleshooting help, chat about all things 3D Printing and Modeling, and show off your builds.
  • And, an exclusive, members-only social network where you can inspire and be inspired, find support and enter build competitions.
 
Only 20 Founding Member spots will ever be offered at our lowest lifetime membership price ever!
P.S. - Your free bonus awaits
Did I mention? All new Scale Speed Garage members instantly receive a bonus .STL file pack containing 10+ .STL files of our popular PSI-style Drag Supercharger, with multiple hat, snout and intake manifold options! Claim yours when you join Scale Speed Garage!
Do you know others who would benefit from this article? Share it with them using the buttons below!
Author: Chris Bell
Chris Bell is a passionate model car builder, resin 3D printing expert and owner of Scale Speed Garage and Bolide Plastic Motorworks.

(He's the one on the left in this picture.)

Want to check out the accurate, detailed model car and truck parts that Bolide Plastic Motorworks creates? Check it out at: www.bolidemodels.com