Beginner's guide to modifying cars

redlinederby Saturday, 4/28/2018
Site manager

Getting your diecast cars ready to modify isn't difficult but making them fast can be. It's a fun challenge that requires only time and few tools. You can go pro and worry about every detail, or just find a car you like and make some simple changes to see what happens.

Photos by 72_Chevy_C210

Taking your car apart

Before you can do anything, you need to take your Hot Wheels or Matchbox car apart. All you need is a drill and a few accessories.

What you'll need:

  • Drill
  • 3/16 drill bit
  • 1/16 drill bit

Step 1: Pre-drill some pilot holes
Use a 1/16 drill bit to drill a guide hole into each rivet on the bottom of your car. You'll notice there's already a little divot there, so just drill into that. Just try to keep your drill straight. You don't have to drill in very far.

Step 2: Grind off the top of the rivet
Use the 3/16 drill bit and drill off the top of the rivet. Go slow and apply just a little bit of pressure. Stay even with the chassis and the top of the rivet will grind right off. You don't need to go down very far...just to where the plastic starts. Check frequently as you drill. Once the rivets heads are gone, your car should just pop apart.

You'll get a few pieces when your car is apart, usually the chassis, body, interior and windows. And now that you have exploded your car, it's time to modify and customize. Read through some of our guides to get you started making fast cars.


Modify and customize

Now that your car is apart you can do with it as you please. You can add weight, swap out wheels and even give it a paint job. Just don't forget to test your build before you glue it together! Use some clay or putty to keep your car together while you test. It's a lot of trial-and-error before you'll find that sweet spot.


Put your car back together

After you've made all your modifications, it's time to put your car back together. All you need is a small (and cheap) tube of epoxy to help glue things back together. You might need to fudge around find the best places to glue things back together, but in general, putting the car back together the way you took it apart is a good place to start.

What you'll need:

  • JB Kwik epoxy ($5 at Home Depot)
  • Toothpicks or mixing sticks
  • Wax paper or small piece of cardboard

Step 1: Piece your car back together
Flip the car over and check to see if the body peg lines up with the hole from before.

Step 2: Mix up a small bit of JB Kwik
You don't need a lot and you can always mix up more. Recycle! I often use opened car blister packs as little tubs for my epoxy.

Step 3: Put the JB Kwik into the holes
Use your toothpick to pick up a some of the epoxy and drop it into the holes. You might need some elsewhere along body lines or whateer, just know that the epoxy sets within 5 minutes and hardens like metal, so don't take too long.

Or use screws

Using epoxy is a quick and easy way to get your cars back together. It works great. But what if you want to test your car while you're building? You can't use epoxy because it's permanent and you don't want to drill it out every time you make a change. 

One solution is to use screws...very tiny screws. You can drill into the chassis posts and then use tiny #2-56 model screws to hold your car together. It's a great solution if you take the time and have the patience. It can be tricky. But it makes it very easy to go back into your car and make changes. Plus, I'd argue it's more reliable than epoxy.

Check out this guide for using screws. It does't require any special tools, just some very tiny screws that you can order easily.


And there you go...you've just cracked open a car and put it back together. Obviously, there's a lot of action that happens between opening and closing but working with Hot Wheels is very accessible. Not to mention you don't need a lot of special tools to start playing.

And don't forget to share your fun! Post build journals of your cars with photos, thoughts, videos and show everyone your process. You'll get ideas and inspire others...including the competition.



Discussion

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rookiekiddo 1/17/20

Can hot glue or a screw be used to put the car back together?


  • Small screws tapped into the rivets or JB Kwik...I'd stay away from hot glue — LeagueofSpeed
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redlinederby 1/17/20
Site manager

You can do screws...very tiny screws. Check out this guide on using screws.

But hot glue...I wouldn't use it for anything you need permament. Hot glue can be good for quick tests and trials, but not for primetime.

I'd also recommend checking out The Archive where you'll find a lot of collections/tags for articles. Lots of good stuff available to read.


  • How long of a screw does it take? I imagine 1 mm longer or shorter could make a world of difference. — leasecard
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Esih_Racing 8/14/24

how about using soldering, can soldering burn the cars rivet?


  • solder cannot burn a rivit... — Stoopid_Fish_Racing
  • recently i was watching a youtube video that soldering can burn rivet so thats why i ask — Esih_Racing
  • How about iron soldering? — Esih_Racing
  • Holding the soldering iron on the rivet/post heats it up and melts the plastic base which then allows the plastic base to be pulled off of the rivet/post. — johnson9195
  • so it was not recommend to use soldering iron? — Esih_Racing
  • the plastic is never the same after melting it. drill and tap is what I do — dr_dodge
  • I haven't tried to use the soldering iron method myself. I'd most likely end up burning my fingers! I also drill and tap the cars I disassemble. — johnson9195
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RalphsRacers 8/31/24

I broke the screw post when drilling out a car, any advice would be great on what to put in place of post and how to keep in place.would lead attach to a metal car body and then drill intonlead for the scree?thankyou


  • brass tube that lightly drives over the post could be soldered first to take a screw, then glue, and drive it LIGHTLY!! down til it grabs — dr_dodge
  • then I must ask, how'd ya break it? — dr_dodge
  • FYI, I hand drill everything built in the past year, sharp bits, pin vises, drill chucks, and valve handles on bits and taps — dr_dodge
  • Dr Dodge's method is quite ok. For the rare occasion, and sometimes ie like some Racing Champios castings, the metal just crumbles when drilled. I may use a bit of plasic straw to go over where the pin was, (cut off to correct height) to enlose the jb weld that will now go into straw. Carefully tap it. — CutRock_R_Marc_D
  • I have messed up a few posts myself. If there is enough left I drill and tap that and use a longer screw. I have used brass tubing to replace a post. How to attach it depends on the damage. — johnson9195
  • Another method I have done when removing the roof off of an SUV type vehicle is to use JB Stick between the post and the body. Once that dries the top of the car and the top of the post can be cut off. The interior (is reusing it) has to be modified to fit around the JB Stick. Maybe that method could help, but not removing the top. Make sense? — johnson9195
  • I have cast new mount spots for frankencars, and the low temp diecast works well. https://www.brownells.com/tools-cleaning/bore-barrel-tools/reamers-cutters/cerrosafe~-chamber-casting-alloy/ — dr_dodge
  • Nice Dr! I dig the Frankencars that you make. — johnson9195
  • thanks! — dr_dodge
  • Did not expect that much feedback. I have a 91’Fotd Escort Rally. The wheels were sticking and i thought i would do a little paint strip and a nee set of axles. Upon drilling out the rivit there was a stubborn bit of rivit stopping the base from the car separating so kept drilling and took too much out. Still new to this. Was thinking of trying a lead soldier where post goes, when set id drill into it and then use a screw to rejoin. Or glue around the inside edge so base has something to support it and then glue sides in place… fingers crossed — RalphsRacers
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