Please check out the new OpenSCAD version here: https://www.printables.com/model/1071373-customize-your-happy-birthday-cake-topper-lego-sty
Original:
This is a cake topper designed to look like Lego plates which spell out “Happy Birthday”. The dimensions of the letters are designed to be 100% accurate to Lego plates, and you can even build on top of the studs! (The back is flat, for easier printing, so you can only build on top of it, not under it). In order to keep the letters spaced accurately and still be legible, I've added a small bevel around the tops and sides of the letters, where they would touch other letters.
I've placed small rounded spikes on the bottom to use to stick it into a cake, and they are also spaced to fit nicely on two jumbo size cupcakes next to each other. The entire topper is 170mm wide, or about 6.9", so this would fit great on an 8" round cake.
My youngest son is absolutely obsessed with Lego, and we're having a Lego themed birthday party at the end of January. I designed this for him and plan to surprise him with it on the day of his party. I'll update with photos of it on the actual cupcakes after the party :)
I tested printing it with a bunch of different settings, and in order to get the studs to fit perfectly in real Lego, I highly suggest going with a nozzle smaller than 0.4, I used 0.2 for the final version, with 0.12 layers. You will likely want to use a brim on this, but depending on your printer you might be able to skip it.
I also printed it a few times using 0.4 mm and 0.6 mm nozzles, and they obviously print a lot faster, but they aren't easy to build on top of - so if you care about the accuracy and want to build on it, use a small nozzle like 0.2 mm or 0.25 mm. If you just need to print it fast for a party and then toss it, go for 0.6 mm and it'll look fine from a distance!
To calibrate your print settings, I've included an A and an I as individual files, so you can quickly print those, see how they look and even test if you can build on them if you want. (These versions do not have the bevel).
I actually prepared the entire alphabet and numbers 1-9 as well (Unfortunately the 7 is a cheat, I could not get a good looking version that had legal studs, so that one is not buildable), so I've added a file with all of those as one single STL. Don't try to print that, open it in something like Tinkercad and cut out the letters and numbers you want :) Again, these do not have a bevel, you will want to add that if you put the letters right next to each other.
The author marked this model as their own original creation.