3D Fire Truck Cake Tutorial

NOTE: My blog has moved to a new location: http://saraelizabethcakes.com. Feel free to browse around my tutorials here, then come check out my new site!

Update 6/30/16: In response to requests, I have added in measurements! Look for the photo/PDF link with the sketches on graph paper. It should have all the measurements you need to create templates for a cake the same size as mine. Feel free to adapt the scale to suite your needs or servings. According to the Wilton cake serving guide, this size of cake serves approx. 50+ people, depending on the serving sizes. :)

Little boys are just the cutest things! I have 3 rambunctious, stubborn ones, who are the sweetest little jewels (along with my gem of a daughter, of course), so you can trust me on this. :) While they're all unique, I have yet to meet one who, at some point or other, isn't infatuated with bright, flashy, red firetrucks.

So, on behalf of mothers of little boys everywhere, I was excited to give a 3D Fire Truck cake a try. My customer brought me a photo of this gorgeous fire truck cake created by Cassandra Noe of HoneyPunch Studios. All props go to this awesome artist! This was by far the best fire truck cake out there, in my opinion! Imitation is the highest form of flattery, so I did my best to replicate her lovely cake, figuring out my own unique technique along the way, which I will be sharing here. There are many ways to do this sort of cake; this is the way I did it!

This cake was complex, so this tutorial is LONG. The basic concepts found in this tutorial can be used for any car/vehicle cake. The most important element of a cake like this is to measure, measure, plan, and measure again! As they say, measure twice, cut once.

To start, your most crucial step: I sketched out the design onto graph paper, with each square representing one real-life square inch. This enabled me to have exact measurements and proportions ahead of time, necessary since I needed to make my gumpaste ladders and other accessories in advance (so they had time to dry, and so that I wasn't pulling all-nighters at the last minute). The wheels aren't pictured, but those should be made in advance as well (more on those later). My sketch told me exactly how long, and how wide those accessories should be in order to be to scale once placed on my finished cake. I referred to this sketch during the entire process.

UPDATE 6/30/17: As mentioned at the start, I finally had the time to sit down and properly sketch out my design with measurements. I know a template would be even better, but my original template is long gone, so this way is easiest for me. I think I’ve included every possible measurement you may need (and then some!) to create your own templates, but if I’ve overlooked something, all you need to know to figure it out is that each square on the graph paper represents 1” in real life. Here is a link to a PDF version.

6/30/16 Update: Measurements!

I baked 2 cakes in 2 jelly roll pans and froze them a week ahead of time. At this point, I also created my gumpaste elements seen here:

Not pictured: 4 Wheels, 2 black rods, housing for lighting on top

The ladders and grills were cut using a #2 disposable scalpel, a ruler, and a pizza cutter. For round elements, I used my piping tips of varying sizes. Always punch out your shapes, rather than cut by hand, whenever possible! This gives smoother lines and more perfect shapes. I used a combination of Wilton silver food coloring spray and silver lustre dust mixed with lemon extract (or cheap vodka) to paint the silver elements. Details were drawn in with a Wilton food coloring pen. The ladder rungs, etc, were glued together using a small paint brush and piping gel. For the housing for the lights on top, attach a strip of white to 2 smaller strips of red on each side, and fold around a pen or dowel so as to create a housing large enough to fit the lights in. Hide competed accessories high, away from the kiddos, and allow to dry for several days. If using all gumpaste, even 24 hours would suffice.

For the wheels, I used my 2" circle cutter to cut four 1/4" rounds of black gumpaste. I then covered each of those with another thin sheet of black gumpaste (using piping gel), and used my curved Wilton Fondant tool to create the grooves around the edges. Using a large piping tip, I cut out the hubcaps from white gumpaste, using 2 more sizes of piping tips to form the inner grooves. Then, using a tiny round piping tip, I punched out 8 small bolts for each wheel, attaching each with a dab of piping gel. Tedious, yes. Hard or time-consuming? Not really. It went surprisingly quickly. Have a toothpick on hand to gently push the small rounds out of the piping tip after punching. Set aside to dry.

For the bases, I used two thickness of MDF board, that can be purchased at Home Depot, and I even had them cut to size there! The thicker base goes on the bottom, and the thinner base acts as your cake support--I'll call that piece the "cake board." I used some wood scraps cut into 2" squares to support and elevate the cake.

Using my drawn diagram, I measured the wheels and the locations of them, and cut in 4 wheel wells, each about 3/4" deep. Next time, I would cut them a bit wider than my drawing, b/c after the fondant is on, etc, you loose some space. I really had to squeeze my wheels in! Cover your base board and your support legs in fondant, and let harden overnight, ideally, before handling.

Base board, Cake board, 5 supports.

I placed the supports on the board, placed the cake board piece on top, then adjusted my placement so that they would be largely hidden by the wheels. With my hand hubby's help, we drilled the cake board onto the supports and into the base board beneath. Next time, I'd use a thicker baseboard to as to have more depth for the screws to grab into. As it was, we opted to also drill in a couple screws from the bottom into the supports for good measure.

Bottom view of assembled base board.

See the airspace underneath? Awesomeness factor jumps WAY up.

Before progressing further, make sure to make a template for carving your cake and cutting your cardboard to go under your cake! You could do this at any point up till now. Using parchment, I traced my shape precisely. You'll notice the inner section is to be 1/2" shorter on each side than the board. Cover your cake board in fondant. This adds a food-safe barrier, and when wet, provides a sticky surface to hold attach to the cardboard that your cake will be on. Also, it will show on the inner segment, where the cake is 1/2" shorter.

Use your template to cut a piece of cardboard (this would be typically called your cake board in a more simple scenario) to form your cake on. Cover it with foil (I use Elmer's Spray Adhesive to attach my foil to the cardboard). I used my drawn measurements, and also added about 1" onto the front of my cake board, and .5" on the back in order to extend beyond the cake and create the look of bumpers. I opted to fondant and assemble my cake in two sections: the front and middle, and the back. I though it would be too challenging to fondant it all at once.

Using your paper template, carve your cake--Ignore the wheel wells. I repeat, DO NOT cut in the marked wheel wells! Your cake should be rectangular, with no notches cut in. The mid-section attached to the front will be a shorter width. I was terrified I was going to forget this important detail. You'll do that later!

Also equally important, either cut down your template or your cake a bit less than 1/4" on all sides. This gives room for the buttercream so that when you fondant the cake, the sides are plumb with the base board. I stacked my cake 5 layers high, so cut 5 of each. You may need to piece together one of the layers with large scraps. Just hide that one 2nd from the top. Crumbcoat your two peices, and place in the fridge to firm up. I used Swiss Meringue Buttercream--the best to use under fondant, and scrumptious to boot!

To carve your wheel well, use a round cookie cutter (you can find a set of these in the cake isle at WalMart, Michaels, etc). Mine was 2" wide and fit perfectly. Punch it carefully into the side of the cake, then use a spoon to carefully scoop out the cake. I do wish my wheel wells had been both wider and taller though, for the record.

Finish carving your cake, referring to your drawing, and apply your final buttercream coat. In the left below photo, you can see I haven't yet carved down the width of what will be the smaller midsection. In the photo on the right, you can see it's been carved down, shorter than the width of the baseboard. Once frosted, your edges of the cake should be even with the edges of the cardboard. Firm in fridge again for 10 - 20 min, and you're ready to fondant!

I left the back side of the middle section uncovered, so as to not add any more thickness in between the middle and the back piece, or it wouldn't fit on my base well. Also, the buttercream will stick to the fondanted back piece, adding more stability. I trimmed my fondant, leaving a small lip to hang down over the wooden cake board. Wet your fondant-covered cake-board, and place your two cakes on it, making sure wheel wells and edges line up. Smooth fondant edges over the cake board, then trim any extra with your X-acto Knife or disposable scalpel.

Whew! Take a breath. The hardest part is done! I covered the front and back extensions with fondant, and painted it silver, along with the exposed cake board on either sids of the mid-section. For the mid-section: I rolled out white fondant, placed some tulle material over it, and rolled it with my rolling pin to achieve some texture. I then measured and cut a piece to go over the middle section, attached with piping gel or water. Unfortunately, this is the one thing that didn't go as planned on my cake. Learn from my mistake! I didn't wait to paint it silver. I painted 2 or three coats of silver onto my cake's mid-section, then left it to dry overnight.

When I went to bed, it looked like this:

When I woke up, the silver section was mis-shapen like this:

Waaahaaa!! See all those wrinkles??? For a perfectionist, this is devastating! I'm still figuring out what went wrong here. Sagging fondant? (it was a soft marshmallow-based fondant) Too wet? Air bubbles? My top 2 remedies are this:

1) Allow the mid-section to dry overnight before painting--but watch it for a while so that if air bubbles begin to form, you can prick them with a straight pin and deflate them.

2) Use a thin sheet of gumpaste instead of fondant. It will be firmer and dry quicker, less likely to sag or become mis-shapen.

Next time, I would do both and watch it like a hawk. Live and learn, right?

From here on out, we're on the homestretch. Cut your stripes, trim, and windows according to your drawing, tweaking as needed. Attach in the usual method. Use an Extruder to create your window borders. Attach your pre-made, dried accessories. For a stronger hold, use melted chocolate candies piped on with a ziplock bag.

To anchor the wheels, stick a toothpick carefully into the back, then push it into the cake behind the wheel (in the wheel well). Make sure to warn clients or guest of any foreign construction elements in the cake!

For the headlights. Use your smallest round cutter, and indent where the lights will go. Use your scalpel/knife to cut out the firm fondant, peel off, then use cutter to help cut into cake, carefully scooping cake out with a tool. I tried to cover the inside with a thin layer of fondant to protect the lights. That was tricky. Use piping tips to assist in cutting trim to go around headlights. These are the lights I used. Battery built in, simply twist the base to turn on or off! Awesome! I found mine at Hobby Lobby in the wedding/floral section. A 10 - pack is $9.99, but with a 40% off coupon (always able to be found online), totally do-able.

In the foreground is the disposable scalpel I use ALL the time. My new best friends!

I painted my base board black, using food coloring mixed with extract. Using hot glue, glue ribbon around the edge of your base board. Turn the lights on, put your lights in place, and BAM!