note : I will mend this broken rice bowl with Kanshitsu Kintsugi method. For Kanshitsu Kintsugi, Urushi is used so please be aware that you may get a rash if Urushi touches your skin directly.
In this lesson, I will show how to grate the surface of the brocken bowl and to how to treat after glueing the pieces together.
What is “Kanshitsu Kintsugi” ？
First of all, let me explain what “Kintsugi” is. “Kintsugi” is a Japanese Traditional Technique of mending a broken vessel with Urushi, Japanese Sumac lacqure. Originally we put together the broken pieces with Urushi, fill in the holes or the cracks with Urushi, then coat it over with Urushi, and then cover with gold or silver powder for finish. (When sprinkling the gold (silver ) powder, we use the term “Kinko (Ginko) wo maku.”) .
On the other hand, this modern technique, “Kanshitu Kintsugi”, we will use more modern material, such as resin, glue and/or putty along with Ursuhi. In that way it will save both time and working process.
Information About the bowl.
- The artist: Kimura Yuji
- The characteristics of the bowl: Milky white ceramic, small rice bowl, shiny glazing.
- Size: DIA. 94mm / H 57mm
- Condition: Broken into half. ( The length of the broken surface: 180mm)
It is so beautifully broken. So perfectly into half, it seems unrealistic.
The boy who has been using this rice bowl must be devastated. No worries, I will mend it perfectly, no problem.
Take a good look at the object and check if there are any other chipped or broken parts.
Look for tiny chipped parts and cracks. Cracks are nasty.
Tiny cracks usually appear before your very eyes after Kintsugi is done and often when I am proudly looking at the finished object.
step 01 Base surface preparation
Tools you need in 《Kanshitsu Kintsugi》for surface preparation:
- ②③Leouter diamond bit. (You can find them at DIY stores,)
- ①Diamond file
First, let’s lightly grate the edge of the broken surface with a file.
File the edge where it is sharp. It will make the afterward process, when attaching the two parts together, much easier.
Do not forget to file the foot of the bowl. This part is so easy to forget.
step 02 Glueing with epoxy.
Tools and materials you need for glueing.
- Tools: ② work surface/board (clear file would do.) ③ spatula (Tsuke–Bera)(▶︎How to make your own Tsuke-Bera.)
- Material: ① Epoxy glue ④Turpentine oils
There are different types of glue, however I recommend the ones that requires 30 to 60 minutes to harden. There are ones that requires only 5 to 10 minutes, it seems a little too short for me.
- Take out the equal amount of both glue.
- Mix it together with the spatula, the glue will start to harden.
note: To make it more easier to see, I added some colour to the glue. ( Not necessary.)
Scoop some epoxy glue with the tip of the spatula.
See the pictures bellow for guidance.
- Spread the glue thinly, like drawing a line using the spatula.
- By pressing the spatula against the working board/table or what ever surface, slide the spatula vertically to the epoxy line.
- There, you have the epoxy on tip of the spatula.
I apologize about this low quality image picture. Please try your best to decrypt the meaning.
Use the epoxy glue on the bottom end part of the spatula.
( Left lower side show in illustration.)
Put the bottom end part glue first, and while sliding the spatula to the side, gradually move the spatula and use the top sharp end side glue.
It seems quite tricky in the first place, but it will become easier and fun after several practice.
Spread the glue vertically against the line from the bottom.
① Move the spatula from the top to the bottom. ② After that move the spatula back from the bottom to the top to spread the glue evenly. If the surface was more rough, this process would have been much time consuming.
Try to spread the epoxy thinly and evenly. When the glue is too thick, it may lead to dislocation when jointing the tow pieces together.
Apply the glue onto the section.
When you have applied the glue to the section, then wait for the right timing to put the two pieces together. If you put the pieces together too early when the glue is not harden enough to hold, it can cause a slippage between the two parts.
note: However, when you have quite a lot to segments to put together, it is not realistic to wait for the right timing. Keep on putting together the broken pieces.
Here is a tip to let you know the exact right timing when glue is ready to assemble.
Put some epoxy glue onto a piece of paper and see when it is ready.
Try poking the glue with the tip of the spatula or a toothpick. If you can feel the stiffness, it is time to assemble.
After assembling all the pieces together, next adjust the small misplacements.
Try to examine from various angles.
When you are satisfied with the assembling, rest the cup until the glue is set completely.
Use the power of gravity and let the cup itself set nicely by the weight of it’s own.
Use any equipment to hold the cup in a desired place.
It may not fit completely. There will be a glue in between the broken pieces so it is more about how you can disguise the gap.
However, sometimes I look at this as a interesting challenge.
Take a look at the object, it’s shape and the effect of the glazing and things like that, and then try to see the total rhythm or the object. Seek for the place where you want that rhythm to change or a place you want to break the rhythm.
If you take a single spout bowel, create a gap under it’s spout to arrange the rhythm, or create the gap 150 degrees away from the spout to compose a movement.
When you see things this way, before you might have been struggling to fix the gap and trying so hard to put it back together as it should have look, but now creating the gap might even bring the broken object to much different level. Where you can explore your creativity and people who understands can only see.
step 03 Shaving and file epoxy glue.
Tools you need in shaving 《Sabi Urushi》 ▶︎ Recommended knives to use in 《Kintsugi》.
- Tools: ① Surgical Knife ② art knife with curving blade ③ Large cutter knife ④ Chisel knife(Hiramaru blade) ⑤ Curving cutter knife shown on the photo bellow.
I personally and highly recommend this ④chisel knife. It makes it so much easier working with this, and when the tools are amazing, it makes the whole process so much fun.
For alternative plan, please look for ⑤ 障子紙用丸刃カッター（Shoujigami-yo maruha cutter; am art cutter especially made for cutting Japanese traditional Shouji paper.) You may find them at DIY store Shouji repapering area. (They weren’t in cutter and knives area.)(This information is only useful if you are living in Japan.)
When grating the outside of the bowl, put the back side of the blade on to the surface.
For the inside, use the front side of the blade.
Just try to grate off the bits thats sticking out. After this time on, when working on with epoxy paste, it will be quite messy.
Next step, we will move on to wet sanding using wet sand paper.
Tools to use for.
- Tools: ③ Small dish ( for water) ④ Waste cloth ⑤ Scissors (Only for sandpaper usage .)
- Materials: ① Water proof sandpaper (I used #600) ② Water
- Tools to use when filing with sandpaper.
- First cut the sandpaper 1cm ×1cm
- fold them in three.
- Dip it in the water in the dish.
Apply a small amount of water and sand it lightly.