Upcycled Glass Jar DIY with Polymer Clay Cane Veneer

If you’ve ever wondered what to do with old glass jars dive into this tutorial for an upcycled glass jar diy project using a polymer clay cane veneer. 

Upcycling glass jars with decorative polymer clay veneers is a favorite project of mine. The first time I made something other than a pair of earrings with polymer clay was when I covered a glass juice bottle with cane slices. I soon had a box shoved under the bed in the spare room to store glass for repurposing.

You can simply reuse glass jars for decoration but they have many functional uses as well. I still use the first peanut butter jar I covered in clay to hold my toothbrush and toothpaste. I have a few in my rolling cart that hold my polymer clay tools. Make one to hold your makeup brushes, a pen holder for your desk, or a vase to hold flowers.

In this tutorial I’m using my Groovy Geometric polymer clay extruder cane to cover the jar. You don’t have to limit yourself there. Upcycling glass jars is fun! And since they have so many uses you’ll want to make them with all kinds of decorative polymer clay veneers.

This upcycled glass jar diy even repurposes the extruded clay scraps. I was playing around with some end scraps from another extruder cane one day and discovered that although they’re too distorted to use in the usual way, if sliced lengthwise they have a nice striped type pattern to them. Ever since then I’ve often used the extruded scraps in this way.

Possibly the trickiest part to covering a glass jar with a polymer clay veneer is making sure there’s no air trapped between the clay and the glass. Be sure to check the veneer from the inside of the jar before curing. You should be able to spot any trapped pockets of air. Either move the pocket of air along until you can push it out at an outside edge or pierce the clay with a fine needle and push out the air before healing the needle hole in the clay.

Sanding the clay after curing is optional but in my opinion it’s well worth the effort. Smoothly sanded polymer clay has a beautifully soft, silky feel. Even with all the pieces I’ve sanded I still bring a newly sanded piece to my husband and demand he touch it so he can appreciate the feel too.

If you’re ready to begin let’s dive into the Upcycled Glass Jar DIY tutorial.

Tools & Materials

• Non-porous work surface (I work on either glazed tile or glass)
• Pasta machine dedicated to polymer clay use (I use an Atlas 180 and will refer to the settings I use on my machine. If you don’t have a pasta machine an acrylic roller and some playing cards will do in a pinch, it’ll just take a little more work.)
• Groovy Geometric extruder cane
• Scrap polymer clay
• Glass jar rescued from recycling
• Sharp polymer clay blade or cane slicer (I love my Lucy Clay slicer!)
• Craft knife
• Ruler 
• Acrylic rod
• Parchment paper
• Stainless steel soap or espresso tamper for burnishing seams
• Sheetrock sanding screen—mine is 100 grit
• Wet/dry sandpaper—I used 400, 600, 800, 1200 & 1500 grits

Directions for Upcycled Glass Jar DIY

First up, you’ll want to make your cane so it has time to cool and firm up before slicing. Click here for the tutorial.

When you make the cane you’ll have some discarded ends from the extruded pieces. Gather those up and make another, smaller cane. Rather than taking crosswise slices from this discard cane you’ll take lengthwise slices for the contrasting bottom strip around the base of the jar.

Now, onto the Jar

Prep your jar by removing the label and all residue. Some labels come off easily with a soak in warm water and a little dish soap. For stubborn labels and sticky residue Goo Gone works wonders.

Once your jar is clean and dry condition some scrap clay and make a strip a little wider than the width of the threads on the jar. Sheet the strip on a medium thin setting (no.4 on my Atlas).

Wrap the strip around the top of the jar, covering the threads and pressing out any air trapped between the clay and the glass. Continue to wind the clay around the top until it’s a little wider than the main body of the jar.

Trim back the clay with a polymer clay blade until it’s flush with the main body of the jar. Roll the jar on your work surface to smooth out the clay then trim the top edge level with the top of the glass using your blade. Round the edge of the clay slightly using an acrylic rod.

Bake the jar at the recommended temperature for your brand of clay for 45 minutes. If your clay scraps are a mix of brands bake at the highest recommended temperature.

When the jar has cooled smooth out any unshapely areas on the the scrap clay. A course grit sheet rock sanding screen makes quick work of this and doesn’t get clogged up with sanding dust like regular sandpaper. And remember to wear a mask as this sanding is done dry and creates dust.

Covering the Jar

We’ll start covering the jar at the bottom and working our way up.

Begin by slicing the small discard cane lengthwise to make a sort of streaky, striped veneer. My cane didn’t quite have the length I wanted so I placed the slices on a thin (no.6) sheet of similarly colored clay. (It was actually just the last of the scraps I mixed up to get a solid color.) I then put the sheet with the slices through the pasta machine on a no.4 setting. This stretched the stripes to a better length.

If you will be sanding your project later it’s important to use base color the same as the cane slices. Stretching them like this makes them thinner and if you sand aggressively in some spots you may wear through the cane slice. Using a base color that matches the cane keeps those thin areas from being noticeable.

Wrap the bottom part of the jar with the stripes. Look inside the jar and make sure there is no air trapped between the clay and the glass. If there is gently work the air bubble towards the edge of the clay and push it out. Trim the bottom edge of the clay flush with the bottom of the jar using a craft knife.

Now, to get the upper edge straight and even all the way around I grab a couple books off my bookshelf and stack them to the appropriate height. It may seem a little odd, but it works, and I’ve yet to figure out a better way.

Place the jar on a scrap piece of paper next to the books so you can easily rotate it. Take the most rigid blade you have and hang a corner over the edge of the books. Snug the jar up to the blade corner and rotate it all the way around until you’re back to where you started. Remove the scrap clay.

Using one of the colors you built the cane with, condition a piece large enough to make a solid strip around the jar circumference. Sheet it on the no.4 setting.

Use a ruler and a craft knife to straighten one of the long edges of the strip of clay. Butt the cut edge up against the striped veneer. Smooth the seam where the ends meet with a finger tip.

Make a slightly higher stack of books and trim the clay as you did before.

The Main Veneer

Measure the circumference of the jar and the height of the remaining space you have to cover to figure out the dimensions of the veneer you need. Your veneer should be a little taller than you need but the width should match the circumference. The beauty of using an extruded cane like this is that it’s easy to trim off a row or two of squares if needed to make it fit.

Cut your cane slices with a sharp blade keeping them a consistent thickness. You should aim to cut them the same thickness as the clay that is already on the jar.

When the pattern of a polymer clay cane allows it, I like to lay my slices in a running bond pattern. I find this makes burnishing the seams easier as I am not trying to join four corners together seamlessly.

Once you have enough cane slices tiled together to make your veneer lay a sheet of parchment paper overtop and burnish the seams. I alternate between using a stainless steel soap or an espresso tamper, my acrylic rod, and a finger tip.

When the seams have been burnished carefully slide a blade underneath the veneer to lift it from your work surface.

Sponge a little liquid clay on the scrap clay portion of the jar—none is needed on the glass itself—and get ready to lay on your veneer. I like to stand up for this part so I am looking straight down on the jar.

Lay the jar on its side and start by placing the center of the veneer in place. Slowly work your way around the jar, butting the bottom edge of the veneer against the clay already in place and checking for pockets of air.

Carefully line up the pattern where the side edges of the veneer meet. Once you have everything in place roll an acrylic rod over the seam to smooth it out. Fold the top edge over the lip of the jar. Trim off the excess by running a craft knife around the inside edge of the jar.

If desired, add a strip of clay to the inside edge of the jar to help hide the scrap clay you used to cover the threads.

Make sure your work surface is clean and free of stray bits of clay and then roll the jar across it a few times to make sure everything is smooth and in place. Carefully check for stray bits of lint, fingerprints, and that all seams have been burnished smooth. Once that’s all been taken care of, it’s time to cure.

Tent the jar and bake at the recommended temperature for your brand of clay for one hour.

Finishing Touches

I don’t always cover the bottoms of my jars but if you’d like to you can once the jar has cooled. Condition a coordinating piece of clay and sheet it on a no.3 or 4 setting. Dab a little liquid clay on the bottom edge of the clay already on the jar. Smooth on the raw clay, carefully pressing out any trapped air pockets. Trim with a craft knife and smooth the raw clay into the baked clay until it’s seamless. Bake for another 45 minutes.

Sanding is optional and although it’s a tedious job I believe it’s 100% worth it. If you’ve ever touched smoothly sanded polymer clay you’ll know what I mean. And if you don’t know what I mean then it’s time to get sanding and find out.

I start my sanding with a piece of 400 grit wet/dry sandpaper, a bowl of warm water with a drop or two of dish soap, and an old dishcloth to work on. This first grit is going to do all the heavy lifting and will take the longest. Keep at it until everything feels smooth and even and there is a haze over every bit of clay when it’s dry. The job of the finer grits it to simply smooth out any lines left behind by the courser grits. 

I prefer a soft, satin finish on my decor pieces as opposed to a glossier finish. Once I’ve finished with the 1500 grit sandpaper I simply rub over the whole piece with a clean cotton dish towel and I’m done.

Notes

If the scrap clay you’re using to cover the jar threads is very dark and the cane veneer is very light colored or sliced very thinly the scrap clay may end up showing through. You can either top the scrap clay with a thin layer of white clay or use a color that you’ve already used in the cane itself.

If you’re unsure how thick to make the first part of the veneer that covers the bottom of the jar build the main veneer first. Then you can determine from there how thick or thin you should roll out the bottom veneer and solid strip.

If baking glass in the oven causes you to worry, I can assure you it’s safe. Glass undergoes much more extreme temperatures when it’s being formed than what we cure polymer clay at. I’ve made plenty of clay covered glass items and have never had a piece break yet. You can start your piece off in a cold oven and let it cool in the oven as well if that makes you more comfortable. I’ve done that as well as popping the piece into a preheated oven and pulling it out when the time is done. Both methods have worked for me without issue.

Now that you’ve reached the end, I hope you’ve enjoyed this tutorial for an Upcycled Glass Jar DIY. What will you use your jar for?

As always, if you have any questions or comments, I’m happy to hear from you.