Welcome to Part 4 of the Optical Illusion Quilt Along! You’ve made it through the piecing, so congratulations! Now we come to what may not be your favorite part of the process: prepping the backing and batting, and basting the layers together in preparation for quilting.

Above is one of the alternate colorways for Optical Illusion. You can make something similar with red, light blue, and white fabric from my online shop.

But if you’ll let me guide you through the next steps, I’ll share some tips to make it less painful and move you along to the quilting that much sooner.

Prep the Batting

The most important step in basting a quilt is to ensure that the batting and backing are several inches larger than the quilt top all the way around.

If you look at the back of the pattern, you’ll see that for the batting size, I have added 6″ to the length and width of the quilt top. For example, the lap-size top is 45″ x 66″. The batting needed is 51″ (45″ + 6″) x 72″ (66″ + 6″).

Example of measuring batting from a previous Quilt Along:

Click here for the Block Chain Quilt Along shown above.

For me, the easiest way to measure the batting is to buy a roll of it, then unroll it across the width of the quilt top and roughly trim off the amount I will need. In the photo above, I’m using Hobbs Tuscany cotton/wool batting which is one of my favorites.

It’s 90″ wide and folded double on the bolt. So after I trim off a chunk from the bolt, I’ll lay the quilt top out and trim off several inches from the top of the batting. I save those chunks to make practice quilt sandwiches later.

Prep the Backing

I used Geo Pop Tiny Hex in black for the backing. Get Geo Pop Tiny Hex for your backing. 

Piece your backing so that it is a few inches larger than the batting size given on the back of the pattern.

For example, for the lap size, I would cut my three yard piece of backing fabric in half crosswise. This gives me two pieces about 40″ x 54″. I need backing a bit larger than 51″ x 72″.

I’ll sew the two pieces together for a backing that’s roughly 54″ x 80″. The seam will be horizontal across the quilt.

Now you are ready to baste!

Basting the Layers: Quick Overview

I baste using my design wall and 505 basting spray. I make sure my batting and batting are bigger than my quilt top and I trim away some of excess after it’s been basted. I spray the top and backing outside separately, then assemble all the layers on my design wall, taking care to smooth each layer as I go.

Once everything looks nice and flat, I’ll roughly trim the edges so that only and inch or two remain around all 4 sides. I cut off as much extra as I can to prevent it from tucking under the back and quilting the quilt to itself!!

The final basting step is to iron the quilt on both sides to set the glue and smooth everything out one final time.

I didn’t have a chance to take pictures of this process while making Optical Illusion, but here are links and tips from previous quilt alongs.

Click here for a step-by-step photo tutorial of how I spray baste my quilts.

If you’d prefer a video, watch my video quilt basting tutorial instead. The video below was made as part of my Infrastructure Quilt Along.

See the same process on my Color Weave quilt. I love sharing a  few different photos and tips, which sometimes helps!

And if you have any more specific questions, you can alway post pics and ask questions in my Christa Quilts Facebook Group!

Next week I’ll include a video showing spiral walking foot quilting practice to get you ready for the most fun part of making this quilt!! I can’t wait!!

Spiral Quilting on Optical Illusion can be done with a Walking Foot or Dual Feed system.

For More about this quilt along

• Click here for the Optical Illusion supply list, blog schedule, and links to previous steps.
• Click here to purchase the pattern and optional fabric to make this quilt.