Please Make Us a Box!

I wish someone would manufacture a fiber box that we could buy and use as a long-lasting firing box for our base metal clay. How hard can it be? Just a step further from the fiber board we use as a kiln shelf.

Until then, here is how you can improvise a fiber firing box.

Buy 2-3 fiber boards. The cost of each is $8-$10.

Use a craft knife to cut a square inside one or two of the boards, about 1/2″ away from the edges. Now you have a fiber “frame.”


The uncut fiber board will serve as the “floor” of the box. Place the frame on top of the “floor.”


As an option, to create a deeper box, two frames (rather than just one) can be placed on top of the “floor,” as shown in the photo below.


Insert nickel-chromium wire (a.k.a. nichrome or high-temp wire) through the frame and through the “floor” board.


Pull the wire through the “floor” and across the outer side of the “floor.” Re-insert the wire through the outer side of the “floor,” and pull it out through the frame.


Cut the wire, leaving at least a 5″ length of wire on each side.

Repeat this with the other two sides of the box.


When making a deep box, instead of a second frame, you can use strips of fiber blanket.


(As an alternative, you can take the small square which you cut out to create the first frame, cut it into strips, and stack the strips on top of the first frame.)

Tie the four ends of the wire together to make a handle for the box.



As a reminder, rather than using a box, you can simply arrange kiln posts around your kiln shelf to make a box.

t-Fiber alternative

(This method is described in the instruction manual for Hadar’s Clay™ Quick-fire Copper and Bronze.) Although this method works fine and is easy to construct, the disadvantage is that it cannot be removed as easily from the kiln, since the kiln posts are not held together.

25 Responses to “Please Make Us a Box!”

  • Donna Lewis Says:

    Hadar, I’m working on that. As of now they are extremely fragile. The issue for me is the cost of buying all these materials. However, I’m working on it. Have made and used four. Two I used in class, one was patched.
    Now that I have stated it, perhaps someone with the means will now rush to get it out there. I’d buy one if it’s more durable than the ones I have put together. They remind me of those meringue cookies just a little firmer (very little) I’ll keep you posted.

  • Tammi Says:

    I should think Paragon could make one out of kiln brick.

  • Christine Damm Says:

    Thanks, Hadar! This is an improvement on the fiber box and very appreciated.

  • Alana, Sonoma, CA Says:

    isn’t there a hardener for this stuff? Then after making the box, you could pour on the hardener (it’s a liquid) and the box would last longer? I think it’s pretty toxic stuff however.

  • Hadar Jacobson Says:


    If you are making it from fiber board you don’t need a hardener. I did try it on fiber blankets and it didn’t work so well.

  • Linda Gaughran Says:

    Wow, so happy you found a solution to my floppy fiber blanket box!

  • Maggie Bergman Says:

    Hi Hadar,

    My background is in pottery and raku firing was one of the things I loved. We built a kiln and used a special adhesive to adhere the fibre blanket to the steel kiln frame.
    This adhesive (a paste, not a liquid) was also use to coat the inside of the blanket (2-3 coats) we left it to dry and it was then fired without anything in it, just to ‘set’ the adhesive. What was left was a hard shell that wouldn’t damage easily.

    Try this adhesive for the fibre boxes, glueing them together and maybe even coating the in & outside to make them more durable. This glue is available at any decent pottery supply shop, anyone that caters for DIY kiln building.

    I would probable still use wire to keep it all supported.

    Cheers from Oz,

  • Hadar Jacobson Says:

    Thanks, Maggie, I’ll try to find it. My local ceramic store sells “kiln cement” to mend bricks. It might work.

  • Dee Bodin Says:

    Hi Hadar, I’m also looking at making one with a product called Heat Resistant Sealant upto 1250C
    using kiln post and shelfs…
    My question is can you use this firing in a box, with the old copper and bronze clay powder, the none QF clay? I still have some left and just wondered…
    Thanks for wonderful info and clay possibilities…

  • Hadar Jacobson Says:


    Yes, as long as you follow the firing instructions for the traditional clay, firing in 2 phases. Please let us know your result with the box!

  • Karyn R Says:

    I am looking at a solution, that would be fairly strong and rigid (not floppy). Because I come from a glass-kiln background and have a large kiln, can you let me know what size or sizes would work best for those working with small or metal-clay-only kilns? I am trying to see how inexpensively I could put something together. I am looking at 2 different materials, and want to see which would work best. I am hoping it would last through dozens of firings at least.

  • Hadar Jacobson Says:


    If I understand your question, then for metal clay jewelry I believe that the smaller the kiln, the better. However, I have been firing successfully in a glass kiln (the hexagonal Skutt). If you fire in a big kiln, you will have better results firing in multiple small boxes rather than one big one, and arrange them all close to the heating elements. I hope it helps,


  • Linda Fountain Says:

    Hi everyone, I recently made a fibre blanket box and was a bit worried about the corners opening up. I found an incredibly simple solution. I pinched the two layers of each corner together and used a large paperclip to hold them together. I’ve done two firings, one copper and one bronze and the paperclips are still holding. I was worried they’d melt, but they are usually made of stainless steel. By the way, I love your clays Hadar, thank you so much.

  • Christine Says:

    Well, I know I am being antsy, but I just put 2 of my white bronze pieces in the kiln. I do not have enough fiber blanket or paper to make a box, so I am using my stainless steel box and carbon without the top. It is currently ramping at 400/hr to 1160 and then holding for 3 hours. I am anxious to see if it works. (Yes, I know. I should fire test pieces first, but I didn’t.)

    Looking around, I tried to find out why a stainless steel box is not a good idea. Can you tell me why?

  • Hadar Jacobson Says:


    Stainless steel is a poor heat conductor. This is one of the reasons I don’t use it anymore. The pieces that you are currently firing may not sinter since the don’t get enough heat because of the the box. If this happens, you will need to raise the temperature.

    The other reason for not using it is that the box oxidizes and sheds black powder into the kiln, which can cause damage in the long run. People mistake this powder for carbon, but since I stopped using the box my kiln is perfectly clean after firing.

  • Christine Says:

    Thanks for the reply, Hadar. I guess I should always follow directions. The pieces did not turn out. They were not powdery on the inside, but they snapped easily. I will wait until I receive an order for fiber blankets before I try again. It will be nice not to have all the messy black stuff from the stainless steel box too! =)

  • Davida Says:

    Hi Hadar!

    Geez…I should have read this blog over again before firing. Never mind responding to my last email (gmail, not hotmail) about the black popping in the kiln, which I thought was carbon, but now see was the steel. I’ve been searching the internet forever now searching for a ceramic box. I’m sure someone would have found one by now, but I just can’t help myself!

    Really hope someone starts making some firing boxes soon! This would make firing mixed metal clay SOOOOO much easier!

  • Annette Holbert Says:

    could you use a heavily poured bisq ceramic box with a lid. I would think it would hold up just fine. with repeated firing.

  • Annette Holbert Says:

    could you use a heavily poured bisq ceramic box with a lid. I would think it would hold up just fine. with repeated firing.

  • Hadar Jacobson Says:


    I guess it would, although I would not use a lid. I tried to fire in a bisque once and it broke at the first firing. But it may have not been high fire stoneware.

  • Meghan Garner Says:

    Hadar (or anyone who can help),

    I made one of these boxes the other day, and was very excited to use it. I was firing fast fire bronze, and because it was my first try with that clay I fired to 1500 for two hours (didn’t want to blister, figured I could re-fire if needed to sinter properly). There were 6 small items in the firing, and 1 medium, all about 3-4 cards thick.

    Everything came out fully sintered, but also very heavily fire scaled, and the largest piece showed significant signs of blistering and melting. Odd, since the smaller ones didn’t melt or blister, and everything was covered in a good 1″ of carbon. I fired without a lid.

    Any idea what happened? My only thought is perhaps overloading – the box I made fits perfectly into the chamber, with only a tiny bit of space between it and the walls. Should I make a smaller box? I’m hesitant to try again until I know what went wrong.

    Love the method, though! Much better than the stainless steel container mess, if only I can get it to work. 😉

  • Hadar Jacobson Says:


    Is your kiln a front loader or a top loader? How were the pieces arranged in the box?

  • Meghan Garner Says:

    It’s a front loader (paragon sc-2), and the pieces were arranged around the edges (avoiding the front and middle).

    I’m just hesitant to try again until I have at least an inkling of what went wrong so I know what to adjust. I know FF bronze can be tricky.

  • Hadar Jacobson Says:


    I have no experience with the kind of bronze that you are using. When I fire Quick-fire bronze (my own brand), I fire at 1520 (at your type of kiln), the same way you described, and none of that happens. It seems that the temperature was too high. I can only suggest covering the pieces with more carbon. The fact that one of them had fire scale make me think that it was exposed to air. That can happen when the carbon burns fast and turns to ash.

  • Meghan Garner Says:


    Thanks for your help! I suppose I’ll try a thicker layer of carbon and a slower ramp, and perhaps a few less items in at once, and see what happens. Still have several packets of this stuff to work through, so hopefully I’ll find a solution. Meanwhile, I’ve ordered some of your clay to play with. 🙂

    Thanks again. I do love the fiber box idea!

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