Adhesive test before attempting to remove polymer clay discs and metal washers.

I’ve been collecting and trying various glues while crossing my fingers that they’d work long-term. I really dislike the thought of something I’ve made falling apart after I’ve sold it, so I decided I needed to test adhesives.


I first baked three test strips of five different brands of polymer clay. I used these in my post, “Does Polymer Clay Shrink?”  Then, I conditioned my bag of polymer clay scraps, cut out 60 discs and baked them.  The scraps were mainly Kato with some Fimo, Premo and a tiny bit of Soufflé, because that’s what I’ve been using.

I thought about making Kato discs to go on Kato clay, etc., but decided a mixture of different brands would make a more rigorous test.

I also decided to not roughen the strips of polymer clay with sandpaper for the same reason.

I got 60 new, zinc-coated, steel washers thinking they could represent bails. They looked clean, but I still washed them in hot, soapy water.  I also cleaned all the washers, polymer clay discs and test strips with a Q-tip soaked in 91% rubbing alcohol. I wore nitrile gloves while doing the test.

All adhesives were purchased within the last few months.  I just bought Liquid Fusion yesterday because I like the idea of a non-smelly glue.

I spread a thin layer of each adhesive on the back of the polymer clay discs and metal washers using a new toothpick for each. (See photo below.) I didn’t want to use too little adhesive, but I also didn’t want to use too much because it looks bad when it seeps out.  I tried to find a balance.

I intentionally left the top part of the disc or washer hanging off the edge of the clay strip to allow me leverage when trying to pry them off.

In the process of applying Kato Liquid Polyclay. Notice the thin layer spread on the back of the polymer clay disc.

I baked Kato Poly Paste and Kato Liquid Polyclay at 300˚ for 30 minutes in a preheated baking box. A baking box is two cheap aluminum pans, one inverted as a lid, with two small ceramic tiles inside.  I preheat it with the lid off using an oven thermometer.

I baked Sculpey Bake & Bond and Lisa Pavelka Poly Bonder at 275˚ for 30 minutes in a preheated baking box. I realize Poly Bonder doesn’t need to be baked, but its heat-resistance is what makes it unique from other super glues.

I baked Fimo Liquid Gel at 265˚ for 30 minutes in a preheated baking box.

After the baked strips were completely cool, I applied the rest of the adhesives. I wore a mask when using most of them, which is important.

I followed the directions on each bottle.  Gorilla Glue needs to be shaken.  Pieces that are superglued need to be pressed together for 10 seconds or more. I’ve learned from prior experience that baking Kato Poly Paste at the recommended temperature is important.  It also becomes stickier if you stir it.

Adhesives in the order tested. I don’t know why I have such a huge bottle of WeldBond.

The adhesives I used were in this order:

  1. Kato Poly Paste
  2. Kato Liquid Polyclay
  3. WeldBond
  4. Gorilla Super Glue Gel
  5. Sculpey Bake & Bond
  6. Lisa Pavelka Poly Bonder
  7. Zap-A-Gap
  8. 3M Super Glue Gel
  9. Fimo Liquid Gel
  10. G-S Hypo Cement
  11. G-S Hypo Fabric Cement (I tried this because it says it’s for plastics.)
  12. Liquid Fusion

The superglues are supposed to be cured within seconds.  The liquid clays should be cured when cool. WeldBond requires more time to dry, so I let it and the rest dry for 48 hours.  Liquid Fusion was a last-minute addition and I let it dry for 24 hours.

Four of the five washers adhered with Lisa Pavelka Poly Bonder popped off before I could take the first photo, so I Scotch-taped them back in place.

After the photo was taken, I really tried to pry each disc and washer off by hand. I was not easy on any of them. My fingertips still hurt, hours later.  One of the Premo strips broke in the process.


The remaining polymer clay discs and metal washers after trying to pry them off.

The photo above looks pretty sparse.  Most of the metal washers popped off very easily.  The polymer clay discs were somewhat more difficult.

The adhesives were all completely dry.  There are circles of adhesive left on the clay strip, so it appears I had good glue coverage.  Of those that popped off, nineteen washers and four polymer clay discs had no visible glue residue.  I believe this shows how the metal resisted the adhesive.

Some of these adhesives might have worked better if I’d done something differently. Many aren’t necessarily meant for use with polymer clay.

The adhesives in order of those that performed best were:

  1. Gorilla Super Glue Gel was amazing in adhering both the polymer clay discs and the metal washers to polymer clay.
  2. Zap-A-Gap was also amazing, except on Cernit.
  3. Kato Poly Paste and Sculpey Bake & Bond worked great for adhering polymer clay to all brands of clay tested.
  4.  Kato Liquid Polyclay worked great for adhering polymer clay to all brands of clay, except Kato.  That’s strange.
  5. Fimo Liquid Gel adhered polymer clay to Fimo, Soufflé and Cernit clays.
  6. Lisa Pavelka Poly Bonder adhered polymer clay to Soufflé.

This test seems to show again that liquid polymer clay is the most compatible with polymer clay.

The clays most receptive to adhesives were:

  1. Soufflé — 9 discs/washers adhered, probably because it has a naturally textured, matte surface.
  2. Fimo — 8 discs/washers adhered.
  3. Premo — 7 discs/washers adhered.
  4. Kato and Cernit — 6 discs/washers adhered.

In Ginger Davis Allman’s post on adhesives, polymer clay artists have reported some adhesives deteriorating over time.  Oh, joy.  In a few months, I’ll try again to pry off the discs and washers.  I agree with Ginger’s advice on burying metal in polymer clay as the surest method.

For now, I’m keeping my Gorilla Super Glue Gel and I’ll continue to use Kato Poly Paste and Sculpey Bake & Bond on polymer clay.


I tested Genesis Heat-Set Oils Thick Medium and Apoxie Sculpt two-part clay as adhesives.

The results in the photo below show that Genesis Heat-Set Oils Thick Medium works well to adhere polymer clay, but not metal, on all clays tested, except Premo.

Apoxie Sculpt two-part clay did not work well to adhere either polymer clay or metal.  However, you can see the leftovers where Apoxie Sculpt did stick to Cernit.

adhesives test Thick Med and Apoxie

In the tests below, I used WeldBond to adhere polymer tiles to gessoed masonite.  It was fairly easy to pop off the tiles.  The grout I used in the photo below was Plus Air-Dry Clay which cracked and fell off.  I tested grouts that didn’t need baking because I’d used resin on some of my mosaic pieces and couldn’t put them in the oven.

Plus Air Dry clay grout test

A bit of good news is that Apoxie Sculpt works well as a grout.  See photo below.  It adheres well to gessoed masonite and Cernit polymer clay.  It doesn’t shrink or crack.  Apoxie Sculpt is very hard when dry.  It comes in various colors and has an open working time of 2-3 hours.  The surface can be smoothed with rubbing alcohol or Aves Solvent.  I put mica powders on it while wet and they seem to adhere well.

Apoxie Sculpt grout test

Fimo Air-Dry clay does not work well as a grout.  As you can see in the photo below, it cracked and didn’t adhere to gessoed masonite or polymer clay.

Fimo Air Dry clay test