GIANT mosaic numbers / letters filled with balloons - Party decoration idea - DIY How to make tutorial - 18th birthday

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I made these giant numbers and love how they turned out!

This project took me two nights. I made the templates first and cut the back of the numbers out.

The next night (day before his birthday) I attached the sides on the numbers and filled with balloons. 

For best results, I would recommend attaching the balloons the day of or the day before.

VIDEO TUTORIAL

UPDATE: To use less paper - don't click CUT MARKS or LABELS when printing.

Some people lose track of how to lay the pages out but if you start horizontal across 4 pages and then start the next row below it. See photo of pages taped. 

Supplies:

PDF number file printed (poster format)

2- 30x40 inch foam board

5 - 20x30 inch foam board

UPDATE:  After making several numbers now (8, 6, 2, 0) I use approx 6 - 20x30 boards

3 boards for the back of the number and 7-8 side pieces. 

Ruler, pencil and exacto knife

Hot glue gun & glue sticks or white tape

I made the template in a PDF file by printing it as a poster. 

Adjusted tile scale to 500% and draft setting to save ink.

**Video shows step by step instructions on how to print**

I have the PDF for #1, 2, 6, 8, and 0. Just email me and I'll send the PDF file. I'll work on making all of them and post an update.

All the pages had a small white border. I didn't worry about all the pages matching up, only the edges of the numbers. 

Taped together and cut the number out.

I found 30 x 40 foam boards at Office Max for under $8. 

I used the larger boards for the back of the numbers. Since the numbers are much larger I also used an additional 20x30 smaller board to fit the entire number. 

Trimmed and attached the two boards with packing tape.

#3,5,6,8,9, and 0 are rounded at the bottom and a little taller than the other numbers. I used the #1 to measure how much to cut off the bottom of the #8. This worked out perfect to make the bottom flat to allow it to stand up. 

I used the 20x30 boards to make the sides of the numbers. Measured 6" strips and cut. Each board made 3 strips and I think I used 5 boards to finish out the 1 and 8. 

Dollar store sells foam boards!!! Same boards at Walgreens were $5.29 each.

I used hot glue to attach the 6" strips around the edge of the #1. The straight edges were the easiest. 

To make the angles you have to lightly score the foam board about 1" apart. 

Don't press too hard. If you do cut complete through, just use tape to re-attach. I didn't have that issue but could easily see it happen.

To make the point in the #8, I scored the foam board on the opposite side from the rounded edges. 

Busy working and watching TV.

Balloons:

I inflated all the balloons different sizes. 

7" chrome balloons - approx 35 

12" light green and dark green balloons - approx 45 

Green & white water balloons

3 random grey balloons :)

Glue dots

NOTE: Next time I'll purchase a bigger variety of sizes. More 7" and some 5" balloons.

I used a hand pump to inflated a bunch of balloons 2 nights before and stored in a trash bag. The rest were done during assembly. 

I would not assemble more than a day in advance. The balloons start to loose air and gaps start to form. For best result assemble the day of or day before.

I used glue dots to hold the balloons touching the board and other balloons. These dots are super sticky. I would only unroll to show one dot at a time to prevent multiple being attached. They don't come off.

I used 200 for the 1 & 8 but ran out and had to use double sided tape. It did not work well. I highly recommend the glue dots. 

I ordered some on Amazon - 3000 (30 rolls of 100). I figured I'll need them for the next birthday. 

I also found these the day after at Wal-Mart for $3.63 for 300.

I used water balloons to make smaller balloons to fill in all the gaps.

I added the same color balloons on balloon stands and placed on either side.

I also used 12" silver confetti balloons. 

So impressive. Great centerpiece to a party or backdrop.

Since my son turned 18 I also made a banner with "18 things you can do now that you're 18."

Free instant download link above.

He loved everything!

I'm now planning for a baby shower, 16th birthday, and graduation!

UPDATE:

I have three other video tutorials on how to make the mosaic numbers and one for USA letters. Each one shows something a little different based on questions I received from people. The 18 was my very first one to make.

2020 Graduation Balloon Mosaics

2nd Birthday Mosaic - Pink, Gold, & White

16th Birthday Balloons - Gold, Black, & White

Red, White, Blue USA letters

You may also like these blog posts:

2020 Graduation Balloon Mosaics

2nd Birthday Mosaic - Pink, Gold, & White

16th Birthday Balloons - Gold, Black, & White

Red, White, Blue USA letters

3rd Birthday Balloon Number - Hot pink & zebra theme

Video tutorial

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