Making a Keyhole Pattern

***Update – A printable pdf pattern is located here, but please note it is only for size 2T.***
I can’t believe this is FINALLY ready. I feel like I’ve been working on this dress for ages! Thanks so much for being patient with me as I went through all those video tutorials, but I really just wanted you to have ALL the information you would need before starting this dress. Now if you get “stuck” anywhere along the way, you will be able to do your own troubleshooting. (Before you e-mail me in a rage about this stupid project that just isn’t working out! lol.)
Seriously though, if anything is confusing, or just giving you a hard time, Please feel free to get in touch with me and I’ll help in any way I can. The fault could definitely be in my wording and not your sewing skills. ; ) So, here we go!
What you’ll need:

a tee or tank that fits your child
a large sheet of paper folded in half – freezer paper will work
a ruler – preferably a clear “quilting” ruler
a pen, pencil, marker – what have you
buttons – preferably the ones you will use on the dress,
 or at least ones of the same size
1. Take your shirt and fold it in half. If you are using a t-shirt, tuck the sleeves to the inside. 
(please ignore the baby drool, I snatched this one right off my kid for the picture.)

2. Place the folded edge of your shirt onto the folded edge of your paper. 
Trace the edge of the shirt front. You only need about 3 inches below the armhole. 

 3. Repeat step 2 but trace the back of the shirt this time. Necklines and armholes are different on the front and back parts of a shirt so be sure everything is smoothed out, and you are tracing the correct edge. 
(below you can see the difference in the armholes)

Now you should have 2 parts traced on a fold like this. 
Be sure to label them Front and Back so you don’t get mixed up.

 4. If you are making this for a small child (under age 3) you may want to raise the back neckline to give yourself more room to work with. This will let you maximize the size of your keyhole. Because the tank top I used had a more racer back shape, I also raised the front neckline, and made the back armholes smaller. 
(the purple lines below)
*When adjusting necklines, the center (on the fold) should start at a right angle to the fold.*
**The length of the shoulder seam should always remain the same on the front and back pieces**
***When adjusting armholes, note that the back armhole should be larger than the front. 
You still want your kid to be able to move around. ***

5. Measure down 2 inches from the bottom of the armhole and square a line across to the fold line. (front & back)
6. Flip the Back pattern over (still folded) and trace the other side through the paper. (pencil line on right side)
7. Unfold the Back pattern and draw a dashed line down the fold crease.

Ok, now for the fun part, the MATH! (yeah right, tell me you hate it too. bleh. but it must be done. note the awesome scribbles in the corner, oh yea, I know what I’m doing!)

So, easy as I can explain…
Take the size of your button (5/8) and add 1/8″ to figure out the length of your buttonhole. 5/8 +1/8 = 6/8
Now add 1/2″ (1/4 for either side) to leave room for the top-stitching, and area around the button. 6/8 +1/2 = 1 1/4″
If your buttons were 1/2″ it would be 1/2 + 1/8 = 5/8 + 1/2 = 1 1/8″

8. Whatever number you end up with, measure down from the neckline on your fold (dashed line) and mark. 
Then measure up the same amount from the bottom of the dash line and mark.
(purple straight lines)
9. Draw your keyhole circle anywhere between those 2 marks. 
I folded them together an marked the center with the green X.
Then I used a compass to make a circle that just touched each purple line.  

Now take 1/2 the width of your button and add 1/4″. 5/16 + 1/4 = 9/16 (fun right!) I’m rounding up. 5/8″

10. Draw a vertical line that distance from the dashed line. (the 2 vertical pencil marks next to the buttons)
The point where the vertical mark and the “purple” mark meet must be a right angle. 
If they aren’t, the keyhole will be distorted when the 2 pieces of fabric overlap for the buttons/buttonholes.

11. Add your seam allowance around the new Back pattern shape. (pink line = 3/8″)
Your seam allowance on your pattern should be the same as the seam allowance on your piping. 
*Note how everything to the right of the dashed line is at right angles. The dash line is the overlap mark.*

12. Add seam allowance to the Front pattern as well. Make sure the side seams (2″ below armhole) 
and the shoulder seams are the same length before cutting out the pieces.
You will need to cut out 2 back pieces for every 1 front piece you cut. 
(1 front, 2 back, 1 front lining, 2 back lining)
****If you are already frustrated, go take a time out, cuz here comes more math. sorry****
The skirt pieces are both rectangles. So I don’t make paper patterns, but they need to be twice the width of the bodice piece and as long as you would like it to be on your child. Then some more math for the placket and seam allowances. (See diagrams below)
For my skirt front I used one 23″ x 13 5/8″ rectangle. Here’s the breakdown…
1/2″ for french seam + 22″ (double Front Bodice width sa – sa) +1/2″ for french seam = 23″
by
3/8 top sa +12″ (2″ below Reli’s armpits to her knees) + 1 1/4″ for hem (turn under 1/4 then turn under 1″) = 13 5/8″
For my skirt front I used two 13 5/8 x 13 5/8″ rectangles. (the square-ness is a total coincidence) 
Here’s the breakdown…
1/2″ for french seam + 10 1/2″ (double Back Bodice width sa – dashed line) + 2 5/8″ for placket = 13 5/8″
by
3/8 top sa +12″ (2″ below Reli’s armpits to her knees) + 1 1/4″ for hem (turn under 1/4 then turn under 1″) = 13 5/8″
If the whole idea of a placket has you TOTALLY confused, try watching this little video. I really made it as easy as I possibly could, and I hope you don’t have a headache at by this point. (or just hate my guts!)


I’m going to try to make a printable PDF (size 2T only) that would make your life a whole lot easier, but to be honest, I need a break. I don’t know how to make PDF’s yet, and I’ve been staring at this same dress for weeks now. Maybe if I get a week away from it, things will look clearer and I’ll be able to focus on the pattern. But for those of you who haven’t already been scared off, this is everything you should need to know. Like I said though, if anything just doesn’t make sense, give me a holler & I’ll try to help. 
GOOD LUCK! I know you can do it, and at least you have a whole weekend to figure it out before I drop the sewing instructions on you. lol. ; )
post signature
P.S. Sorry for all of you that use the metric system, but I’m not sure if I’m smart enough to make those conversions. Hopefully you are. 

8 thoughts on “Making a Keyhole Pattern

Leave a Reply

Your email address will not be published. Required fields are marked *