How to Cut and Mount an RC Touring Car Lexan Body

You've got a fresh touring car body ready to go, but the thought of cutting into it makes you nervous.

Maybe you've botched a trim line before and ended up with a jagged edge that looked like you cut it with your teeth. Or you've reamed body post holes too big and now the shell wobbles around mid-race. Wheel wells that rub tires, clearance settings that are pure guesswork, bodies that sit crooked no matter how many times you adjust them.

It's frustrating, especially when these shells aren't cheap. But lucky for you, this guide fixes all of that.

You'll get exact clearance measurements (not vague suggestions), a breakdown of which tools actually matter, and a step-by-step process that works the first time. We've mounted hundreds of bodies on our race team cars, and these are the methods we use every time.

Tools You'll Need to Cut and Mount an RC Body

Eight tools make this job faster and more accurate:

• Body reamer: Creates precise holes for body posts. A sharp tip is essential.
• Lexan scissors: Curved blades work best for wheel wells and wing edges.
• Hobby knife: Great for straight cuts along trim lines, especially on thin bodies.
• Body post markers: Magnetic markers hold the body in place while you line everything up.
• Marking pen: For marking post holes and wheel centers.
• Ride height gauge: Helps set consistent ground clearance.
• Caliper: For precise left-to-right centering.
• Ruler: Useful for checking body position front to back.

You don't need every tool on this list to get started, but having the right body and cutting tools makes a real difference in cut quality. For a broader look at workshop essentials, see our guide on basic tools every hobbyist should have.

Once you've got your tools sorted, there's one decision to make before you start cutting.

Should You Mount the Body Before or After Painting?

You can mount either way, but doing it before painting gives you better visibility.

With a clear body, you can see exactly where the chassis sits, where the wheels line up, and whether your marks are accurate. That's harder to judge through a painted shell.

That said, plenty of racers paint first and mount later without any issues. Just take your time with alignment if you go that route.

If you're new to painting RC bodies, our guides on how to paint an RC car body with liquid mask and painting without masks cover the techniques you'll need.

With that decided, let's get into the actual cutting. First up: the trim line.

How to Cut the Body Along the Trim Line

Start by cutting along the lower trim line printed on the body. Don't cut out the wheel openings yet.

You have two options here: Lexan scissors or a sharp hobby knife. Both work, and most people develop a preference over time. Let's look at how to use each properly for cutting.

Using a Hobby Knife

The knife is perfect for straight sections on thin 0.5mm lightweight bodies.

For starters, place the body on a solid surface like a setup board. You don't need to cut all the way through the polycarbonate. Score about halfway through the material along the trim line, then bend and snap the excess away. This scoring and snapping method leaves a cleaner edge than trying to cut through in one pass, and it's much easier to follow a straight line.

Using Scissors

On the other hand, scissors cut through more easily for thicker standard bodies.

To do this, cut directly along the trim line in smooth, steady strokes. Let the blades do the work rather than forcing them. Curved Lexan scissors are better for wheel wells later, but straight cuts can be done with either type.

Additional tips for clean cuts: Always use a sharp blade. Dull tools cause ragged edges and make it harder to follow the line. Keep your cutting hand steady and turn the body rather than twisting your wrist into awkward angles. Rushing is the most common mistake here. An uneven trim line is obvious once the body is mounted, and you can't un-cut material. Take your time and let the tool do the work.

Alright, trim line done. Now comes the part that determines whether your body sits rock-solid or wobbles around like a dashboard bobblehead.

How to Mark and Ream Body Post Holes

With the trim line cut (but wheel wells still intact), it's time to position the body on your chassis and mark where to ream the post holes.

Marking the Holes

Magnetic body post markers are a huge help here. Place them on your chassis body posts, set the body on top, and the magnets hold everything in place while you work on alignment. Trust us, trying to hold a floppy polycarbonate shell in position while marking holes is an exercise in frustration without these.

Center the body left to right using your ruler or caliper. Measure from each side of the body to the wheels or chassis edge to make sure it's even. Then decide where you want the body positioned front to back.

Many modern touring car bodies have alignment lines printed on them to help with left-right centering. Use these if your body has them.

A note on body position: Where you mount the body front-to-back isn't just about fit. It's a setup tool. Moving the body forward by 2-10mm increases steering response. Moving it backward adds stability but reduces turn-in. Some newer touring cars have adjustable body posts that let you shift position later without remounting, which makes experimenting easier.

If you're new to a body style or trying one for the first time, start with the body in a neutral position (centered over the chassis as the manufacturer intended). Get used to how the car handles before making adjustments. You can always remount later once you know what the car needs. For more setup tips, check out our short setup guide and preparing for a raceday.

Once you're happy with the position, mark the center of each body post with your marking pen. Then use a body reamer to create the holes.

Ream each hole just large enough for the body post to slide through freely, but not so large that the body has play or wobbles on the posts. A sharp reamer tip makes this much easier to control. If your reamer is worn or damaged, replace the cutting head (some reamers have spare cutting heads available) or get a new reamer entirely.

Go slowly here. On thin lightweight bodies especially, it's easy to tear the material or make the hole too large if you rush. Check the fit after every few twists of the reamer. An oversized hole means a wobbly body, and there's no good fix for that besides starting over with a new shell.

How to Set Body Height and Ground Clearance

Your car should be at normal ride height when you set up the body. If it's sitting on blocks or has the shocks disconnected, your clearance measurements won't be accurate.

Set the ground clearance under the front lip of the body at 8-9mm. This works well for most track conditions. The clearance under the sides of the body should be slightly higher, around 9-10mm.

You can set body height with standard body clips, but for more precise and repeatable adjustments, use body height adjusters or rubber body pads:

• Xray Alu Adjustable Body Post Stop (2)
• Muchmore Perfect Body Height Adjuster
• Muchmore Premium Body Cushion O-Ring Set (20pcs)

These measurements are starting points but adjust if necessary. They will also depend on the tracks your RC car is racing on. High-grip carpet tracks may need slightly less clearance (7-8mm) to keep the body closer to the chassis. On the other hand, bumpy outdoor asphalt tracks may need more (10-11mm) so the body doesn't scrape when the suspension compresses.

Don't skip this check: Press down on the car so the chassis nearly touches the ground. There should still be a few millimeters of clearance at the front and sides of the body. A lot of people set clearance at ride height and call it done, then wonder why their body has scrape marks after running. The suspension compresses during driving. If the body scrapes when you push down, raise it slightly before moving on.

Your body is sitting pretty at the right height. Time for the part that trips up a lot of people: wheel wells.

How to Cut Wheel Wells Without Rubbing

Now that the body is sitting at the correct height on the posts, you can mark and cut the wheel openings.

First, mark the center of each wheel axle on the body using your marking pen. These marks become your reference points for cutting.

To cut the wheel wells, you can use a circle cutter or curved Lexan scissors. Scissors are more common and work great if you take your time. Let the curved blades do the work rather than forcing them through the material.

If you're using scissors, place a spare tire on the body using your axle marks as the center point. Trace around the tire with your marking pen to create a cutting guide.

From here, cut generously. This is where people get conservative and regret it. The opening needs to be large enough that the tire never touches the body, no matter where the suspension is in its travel or how far the steering is turned. Pay special attention to the area behind the front and rear wheels. This is where tires most commonly catch on the body if the opening is too small. You can always trim more material, but you can't add it back.

After cutting, round off the corners where the wheel cutout meets the lower edge of the body. Sharp corners create stress points that can crack over time. A few seconds with scissors now prevents a split body shell later.

How to Mount and Position the Rear Wing

The last major step is cutting out and mounting the rear wing.

For curved wings, scissors are usually easier to control than a knife. Cut along the wing outline, then locate the endplates. These are typically found inside the front wheel cutout area of the body.

Endplates attach to the wing with double-sided tape. They're not required, but they do affect stability. Most racers use them.

If you're running a super thin lightweight body, the included wing may flex too much at high speeds. This is especially true for modified class racing or outdoor tracks where you're carrying more speed. Consider upgrading to a thicker aftermarket touring rear wing that resists flex better.

When mounting the wing, use large wing shims between the wing and body. These protect both parts in a crash by absorbing impact. Some bodies include shims; others require you to buy them separately from the touring rear wings category.

Mount the wing at the position marked by the manufacturer. This is your baseline. Once you've run the car, you can experiment with wing position to tune handling. Moving the wing forward adds rear grip; moving it backward reduces rear grip.

Speaking of tuning, the wing isn't the only thing you can move around. Body position itself is a setup tool.

Body Position Tuning Tips

Body position isn't just about fit. It's something you can adjust to change how the car handles.

Moving the body forward by 2-10mm increases steering response. If your car feels lazy entering corners and you've already tried other setup changes, shifting the body forward is worth testing. Moving the body backward has the opposite effect, adding stability but reducing turn-in.

Some newer touring cars have adjustable body posts that let you shift position without remounting. If your car has this feature, use it. It makes experimenting much faster.

When you're new to a body style or trying one for the first time, start with the body in a neutral position (centered over the chassis as the manufacturer intended). Get used to how the car feels before making adjustments. 

Before you button everything up, let's talk about the mistakes that catch people out, even experienced racers.

How to Cut RC Body FAQs

Is it better to cut an RC body with a Dremel or hobby knife?

A hobby knife or Lexan scissors work best for initial cuts. A Dremel with a small sanding drum is useful for smoothing rough edges afterward, but it's not the right tool for making the primary cuts. It removes material too aggressively and is harder to control along a trim line.

Can I mount an RC body without drilling holes?

Some cars use clip-on body mounts or magnetic systems that don't require holes. Standard touring cars, however, need reamed holes for body posts. That's just how the mounting system works on most competition chassis.

How do I fix mistakes after cutting an RC body?

Rough edges can be smoothed with fine sandpaper (400-600 grit) or a sanding drum on a rotary tool. If you've made body post holes too large, body post shims can take up the slack. Wheel wells that are too small just need more trimming. Unfortunately, there's no fix for cutting off too much material in the wrong place.

Does this guide work for off-road RC bodies?

This guide is specifically for touring (on-road) cars. Off-road bodies like those for buggies and trucks have different clearance requirements and often come with pre-cut wheel wells. The general principles of marking, cutting carefully, and checking fit still apply, but the measurements and techniques differ.

Get Your Body Mounted and Hit the Track

You've got everything you need to mount your touring car body the right way. The next step is simple: clip the body on, double-check your clearances, and go run a few packs. Don't obsess over perfection on your first outing. Get the car on the track and see how it feels.

After a few runs, you'll have a better sense of whether you need to adjust body position or wing placement. That's the fun part. Small changes to body position can noticeably affect handling, and now you know how to make those adjustments without starting from scratch.

Browse our 1/10 touring car bodies to find your next shell for your next build, or stock up on body and cutting tools so you're ready when race day comes.