Japanning / Enemal kiln

[tnimble]

What to do when you've got a decent but battered tool? Simple restore it and tune it up like shown to us in the past by LordNibbo or Woodbloke who proudly presented us with his T5 only today.

Simply said but what about large tools like a Stanley #8? The el-cheapo small household oven I normaly use for firing the Japanning already has trouble taking a #5 1/2.

The full size oven in the kitchen would take up to about a #7 but while it would fit I don't want it in there. I have some trouble with plumbium lamb stove, resin cupcakes or turps bread.

Doing some research it turns out one of the cheapest construction materials AAC (Autoclaved Aerated Concrete) is not only a very good thermal isolator but also can take huge temperatures. Excellent material for building a kiln.

With 12 AAC stones I build a kiln to fit the #8. 4 stones for the floor, 4 for the sides and 4 as a lit. I removed the heating elements from the small household oven.

Before really starting up the kiln you must do a couple of low temperature cycles to get rid of the moister in the stone. To let the air escape easily I used only 3 stones for the lid at first. I heated it up to 90 degrees centigrade. Although the stones feel very dry, there is a lot of water contained in them! There is a lot of steam. So much the insulated glass and shop walls went dripping wet with the shop door open.

(don't mind the mess)


After a couple of hours the steam was gone and I slowly increased the temperature to about 300 degrees centigrade.

Today I placed a #8 and #6 in the kiln and set it to heat to 150 and then to 200 degrees centigrade. The stones now remain cool and the shop temperature does not heat up to about 30 degrees as with the small household oven.


Theoretical when using the correct heating elements you should be able o build a good kin with AAC that can heat to 1300 degrees centigrade. Usable to melt metals and bake ceramics.

 

[Anonymous]

Nice work :wink:

Why use enamel and heat it up to cure it though?

Rob (woodbloke) used hammerite paint on his planes, and that is air dried and is extremely tough after a few days (I used it on a Record #6 2 years ago and the paint is still perfect).

I ask as heating the planes might encourage the metal to 'move' which would then mean lots of work flattening etc.

 

[tnimble]

Nice work :wink:

Why use enamel and heat it up to cure it though?

Very good question indeed. More original if you care for that. But thats not my reason. At least with black the colour is much more deep with real Japanning. Or a least with the recipe I currently use. Which is:

- 19.96 gr asphaltum
- 50 ml boiled linseedoil
- 4 ml cerussite (lead carbonate)
- 2 ml white vitriol (zinc sulfate)
- 400 mg pigment ivory black (or lamp black) with some prussian blue.
- 5 gr shellac
- 100 to 200 ml spirits of turpentine

Rob (woodbloke) used hammerite paint on his planes, and that is air dried and is extremely tough after a few days (I used it on a Record #6 2 years ago and the paint is still perfect).

Nothing wrong with that. For blue on a Record probably my choice as well. Mixing a good bright colour is not as easy as it might seem.

I ask as heating the planes might encourage the metal to 'move' which would then mean lots of work flattening etc.

The metal should not move using a slow heating cycle from room temperature, to 150, to 200 degrees centigrate and very slowly back to room temperture.

I usually do the sole and side flattening and squaring on 60g and 100g before doing the Japanning. and then continue the flattening on 150g, 240g, 400g and 600g. After flattening I polish the sole and sides on a sisal wheel and then on a woven wheel.

I never had any plane come out in any other shape than as flat and square I put them in. Mind you I'm very picky on what is flat and square.

I always make them concave in such a manner that the mouth is fully flat (no light shines through when putting a try square on it with a good light behind it) and in only very little light shines through at any other place both across the width and length. Using David C paper method it under one thou. Prob about a 1/2 to 3/4 thou.

 

[Chris Knight]

That nice tip about the AAC. I reckon the plane makers amongst us might just have a use for it..

 

[David C]

What a great Kiln, and how splendid to use proper Japanning.

(I'm sure Hammerite works just fine but this is somehow more authentic).

Where do you source all those chemicals please?

David Charlesworth

 

[David C]

What a great Kiln, and how splendid to use proper Japanning.

(I'm sure Hammerite works just fine but this is somehow more authentic).

Where do you source all those chemicals please?

David Charlesworth

 

[bugbear]

What a great Kiln, and how splendid to use proper Japanning.

(I'm sure Hammerite works just fine but this is somehow more authentic).

I find hammerite prone to chipping - perhaps members of this forum take sufficient care of their planes that this is not an issue.

BugBear

 

[tnimble]

I've had little trouble at getting them. The local arts store had them all since the ingredients are all quite common in litography and making oil paints.

 

[jmk89]

I've had little trouble at getting them. The local arts store had them all since the ingredients are all quite common in litography and making oil paints.

Would it be too much trouble for you to provide the product names and manufacturers for the white lead, zinc sulphate and the pigments. White lead in particular seems difficult to get (at least in Australia) - probably because of its toxicity, and the only form I can find it in is mixed in with linseed oil or walnut oil.

Many thanks

Jeremy

 

[mahking51]

Hi Tnimble,
Great post!
would it also be possible to give a quick blow by blow of the japanning process?
I have the stuff published on the web but would like to hear it again first hand as I am sure others here would too.
Regards,
martin

 

[tnimble]

I've had little trouble at getting them. The local arts store had them all since the ingredients are all quite common in litography and making oil paints.

Would it be too much trouble for you to provide the product names and manufacturers for the white lead, zinc sulphate and the pigments. White lead in particular seems difficult to get (at least in Australia) - probably because of its toxicity, and the only form I can find it in is mixed in with linseed oil or walnut oil.

Many thanks

Jeremy

Not at all. The white lead and zinc sulphate I currently use is from Scheveningen and comes premixed in a 100ml glass bottle. But other art paint manufactures ike W&N sell it is a siccative. I could also buy it separately as a powder which has to be ground in methylated spirits or an light oil.

The asphaltum is from their own brand but can be found under the name Gilsonite.

The shellac, bees wax speak for them selfs. I've used both orange and blonde shellac flakes this does not seem to make any difference. You don't have to dissolve the flakes in alcohol.

The boiled linseed oil is a bit of a odd one. You've got linseed oil, boiled linseed oil, blonde or decoloured linseed oil etc. I've found out that nowadays the names on the bottles don't represent the same substance as the name did a century ago where the recipes come from. This phenomena is quite common in fact.

Production speed and cost are very important nowadays. This results in companies searching for faster ways to make something that has the same end use but not strictly the same end product. Boiled linseed oil most common use is as the medium in a oil paint. The boiling of the oil causes the oil to cure or in fact oxidate in weeks instead of years. Since boiling oil is quite time consuming it has been replaced by chemically gibing the oil a pre-oxidation. This also causes the oil paint to dry in a few weeks instead of years. But it does not give the oil all the properties given by the kettle or sun boiling process.

For japanning ground we're not using kettle boiled linseed oil so that out paint dries fast. Our drying comes from the evaporation of the turpentine and our curing from the kiln firing. In japanning the oil is used as a leveling compound.

I boiled my own linseed oil. A process that is quite easy but also quite smelly. You simply put a smaller keetle or metal cup a larger kettle and fill the inbetweens with fine sand. Put in the oil in the smaller and heat the larger. I prever using an electric cocking plate. I do not consider oil and open fire to be particular good friends.

The boiling takes about 4 to 8 hours. During that period the oil smokes a lot and produces some awkward smell. After a few hours f boiling the smokes reduces and the oil turns dark and thick but remains clear.

You should be able to source real pre boiled linseedoil under a name like double boiled linseed oil. I found and still find it fun and daring enough to boil my own.

 

[tnimble]

Hi Tnimble,
Great post!
would it also be possible to give a quick blow by blow of the japanning process?
I have the stuff published on the web but would like to hear it again first hand as I am sure others here would too.
Regards,
martin

The mixing of the japanning ground can be found on the net. In particular a description of the process using a cold mix of only dissolving some asphaltum powder and than adding some oil. This description also talks about a hot mix which is regarded as not functional. Their explanation is sought in that in the past they would have needed the hot mix because not having asphaltum powder but blocks.

This assumption is false and the hot mix is functional and the hot mix recipe is functional. Asphaltum requires quite a bit of heat to liquefy and goes very easy again from a liquid into a solid or burn up into carbon.

Also their hot melt recipe although it is a working one does not give a top quality Japanning ground. This due to the lack of either shellac, pitch of resin and the previously mentioned lead and zinc minerals.


What goes best is to put a metal can on an electric cocking plate. Gently warm it up and watch the powder. At about 200 to 250 degrees centigrade the powder becomes shiny and then liquefies. At that point add the oil and start stirring. Add all other recipe components except for the bees wax and turpentine. Watchout with the lead and zinc minerals it is best to first reduce the heating and add a little at the time in order to prevent over boiling the mixtture. Reapply heat and let it boil for about 30 mins to an hour.

Then let is cool down a bit and add the beeswax and some turpentine. Wait for it to cool down before adding the final amount of turpentine to get it to a appliable paint.

 

[tnimble]

To Japan a piece of metal first clean off all rust and loose odds and bits of old japanning. Paint has to be completely stripped. Old japanning can remain but sometimes its easier to start on complete bare metal.

Apply a thin layer with a fine artists brush and let this dry for about hour. At this time its dry enough for the kiln. Fire it at about 150 degrees centigrade for about 30 to 45 minutes then raise the temperature to 200 degrees for about the same amount of time and genlty let it cool down.

Sand out the surface with some 400 grit paper and reapply a thin layer and repeat baking in the kiln. You'll find out the casting of some planes to be quite clean and of others quite rough. The rough casting need a few more layers.

Now comes the fun part instead of sanding clean the surface with steel wool 000 or 0000 and apply a layer of just linseedoil. This can be done with a brush or a cloth. Now bake this again in the kiln for about half an hour at 140 and about the same amount of time at 180 degrees. Redone with some steel wool and apply a second layer of linseedoil. This is now baked for about a quarter to half an hour at 140.

The tool should now be darker than the night and be almost as reflective as your rear mirror.

 

[Chris Knight]

What a smashing description - japanning has to be a real labour of love!

 

[jmk89]

Not at all. The white lead and zinc sulphate I currently use is from Scheveningen and comes premixed in a 100ml glass bottle. But other art paint manufactures ike W&N sell it is a siccative. I could also buy it separately as a powder which has to be ground in methylated spirits or an light oil.

The asphaltum is from their own brand but can be found under the name Gilsonite.

The shellac, bees wax speak for them selfs. I've used both orange and blonde shellac flakes this does not seem to make any difference. You don't have to dissolve the flakes in alcohol.

The boiled linseed oil is a bit of a odd one. You've got linseed oil, boiled linseed oil, blonde or decoloured linseed oil etc. I've found out that nowadays the names on the bottles don't represent the same substance as the name did a century ago where the recipes come from. This phenomena is quite common in fact.

Production speed and cost are very important nowadays. This results in companies searching for faster ways to make something that has the same end use but not strictly the same end product. Boiled linseed oil most common use is as the medium in a oil paint. The boiling of the oil causes the oil to cure or in fact oxidate in weeks instead of years. Since boiling oil is quite time consuming it has been replaced by chemically gibing the oil a pre-oxidation. This also causes the oil paint to dry in a few weeks instead of years. But it does not give the oil all the properties given by the kettle or sun boiling process.

For japanning ground we're not using kettle boiled linseed oil so that out paint dries fast. Our drying comes from the evaporation of the turpentine and our curing from the kiln firing. In japanning the oil is used as a leveling compound.

I boiled my own linseed oil. A process that is quite easy but also quite smelly. You simply put a smaller keetle or metal cup a larger kettle and fill the inbetweens with fine sand. Put in the oil in the smaller and heat the larger. I prever using an electric cocking plate. I do not consider oil and open fire to be particular good friends.

The boiling takes about 4 to 8 hours. During that period the oil smokes a lot and produces some awkward smell. After a few hours f boiling the smokes reduces and the oil turns dark and thick but remains clear.

You should be able to source real pre boiled linseedoil under a name like double boiled linseed oil. I found and still find it fun and daring enough to boil my own.

Thanks for that.