Cone 10 Engobe for H550
White
|
Code # L3954N |
Batch # 3 |
| Materials | Amt |
|---|---|
| Nepheline Syenite | 10.000 |
| Silica | 20.000 |
| OM #4 Ball Clay | 60.000 |
| Bentonite | 2.000 |
| Additions | |
|---|---|
| Zircopax | 10.000 |
| *Mason 6600 Black Stain | 10.000 |
Total:112.00
|
Si:Al: 6.1:1 5.5 (Molar:5.0) 6.4 |
Notes
*This is the product of a series of tests where the percentage of nepheline syenite was progressively reduced (from 25% originally) to reduce the firing shrinkage to match H550 (it is important that engobes shrink the same as the body or they will flake or crack off during firing or later during ware use). Amazingly only 10% nepheline syenite is needed to make this fit Plainsman H450, H550. Again, do not use this recipe on porcelains (e.g. P700) or whitewares (e.g. H570, P600), the recipe needs more nepheline for them (to increase firing shrinkage, we have another recipe, L3954J that does this).
This engobe is very plastic so it sticks well to leather hard clay (because of the high percentage of ball clay). If you don't have this brand name of ball clay then substitute for another.
The zircopax makes this fire quite white. If you want black, switch it to 5-10% Mason 6600. Be careful with other stains, some of them will flux and increase the fired shrinkage.
To mix this follow the instructions on using an engobe at the Digitalfire Reference Library. Our approximate recipe is: Mixed 3000 grams powder with 2380 water to get SG 1.47. Darvan 9.5g. That amount of Darvan works in our studio with our water and material (yours will be different). Start with 8.0 and add more until it is thin enough. Be super careful not to add too much (if you do it might be necessary to thicken the engobe with some Epsom salts, but again, a little at a time to avoid gelling it).
Pictures
Untitled
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Variations
1 - Black
We normally use 10% black stain, but have tested lesser amounts down to 5%. Just use as much as you need to get the degree of black you want.
Testdata
SHAB - Shrinkage/Absorption
| DLEN | FLEN | FWT | BWT | CONE | DSHR | FSHR | ABS | |
| 10 | 93.23 | 85.7 | 41.41 | 42.1 | 10.0 | 6.8% | 8.1% | 1.7% |
| 12 | 93.29 | 85.30 | 39.50 | 40.23 | 10.0R | 6.7% | 8.6% | 1.8% |
| 9 | 93.19 | 86.24 | 40.61 | 41.65 | 9.0 | 6.8% | 7.5% | 2.6% |
| 8 | 93.35 | 86.71 | 42.39 | 43.87 | 8.0 | 6.7% | 7.1% | 3.5% |
| 7 | 93.05 | 87.12 | 40.38 | 42.14 | 7.0 | 7.0% | 6.4% | 4.4% |
| 6 | 93.28 | 87.75 | 40.6 | 42.93 | 6.0 | 6.7% | 5.9% | 5.7% |
| 5 | 93.35 | 88.63 | 40.53 | 43.62 | 5.0 | 6.7% | 5.1% | 7.6% |
| 4 | 93.51 | 89.24 | 39.14 | 42.85 | 4.0 | 6.5% | 4.6% | 9.5% |
XML (to paste into Insight)
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Cone 10 Engobe for H550" keywords="White" id="136925" key="zt6u9W9e" date="2023-05-28" codenum="L3954N"> <recipelines> <recipeline material="Nepheline Syenite" amount="10.000" tolerance=""/> <recipeline material="Silica" amount="20.000" tolerance=""/> <recipeline material="OM #4 Ball Clay" amount="60.000" tolerance=""/> <recipeline material="Bentonite" amount="2.000" tolerance=""/> <recipeline material="Zircopax" amount="10.000" added="true"/> <recipeline material="Mason 6600 Black Stain" amount="10.000" added="true"/> </recipelines> </recipe> </recipes>
Born: 2016-12-12, Modified: 2023-05-28 22:49:42
Black Cone 10 Whiteware Engobe Recipe
For Plainsman H570
|
Code # L3954J |
Batch # 3 |
| Materials | Amt | |
|---|---|---|
| Nepheline Syenite | 15.000 | 16.76% |
| Silica | 15.000 | 16.76% |
| Ball Clay | 57.000 | 63.69% |
| Bentonite | 2.500 | 2.79% |
| Additions | ||
|---|---|---|
| *Mason 6600 Black | 10.000 | 11.17% |
Total:99.50
Notes
*This is a variation on L3954N. This has a higher fired shrinkage to match more vitreous bodies (like Plainsman H570, P580 which have 0.5-1% fired porosity). However this does not shrink enough to match a vitreous Grolleg porcelain (like P700), more nepheline would be needed.
Batch Ticket Notes
Mixed 3000 grams powder. with 2380 water to get SG 1.47. Darvan 9.5g.
April 10/18 Joe tried a gum version:
L3954J powder 500 gms.
Water 280 grams
Laguna Gum Solution 75 grams.
This just so fits in a 1 pint jar.
This flakes on the insides of P700 pieces and pulls dramatically toward itself on an EBCT with P700.
Pictures
H570 P6629 has no solubles, works with black slip
L3954J engobe fit is perfect (as can be seen on the straight CLWC engobe compatibility test bars.
Something is wrong because the engobe shrinks 2% more on firing.
G2571A on H450 with L3954J black engobe
Fired at cone 10R. The black engobe has been applied inside and half way down the outsides.
Glaze on left is G2571A with 5% added rutile (Bamboo).
On the inside of the first mug is GR10-C Ravenscrag silky matte. The black engobe appears black under the clear glaze but brown under the bamboo glaze.
L3954J Engobe fit cone 10R
Back to front: H450, H550, H570 and white version of same engobe
For some reason the fit is almost perfect on all except H550 (toward 550 on drying, toward J on firing for a total of 7mm).
L3954J and H are compatible
The black stain is not changing the fired shrinkage.
G2571A of black and brown L3954 engobe
On H450 at cone 10R
L3954 cone 10R engobe fired bars
On P700 flakes inside, outside OK
The shrinkage difference is not great enough for this dramatic result so the engobe is not forming a good bond with the porcelain.
With P700
Pulls 11 toward the J on drying and then back straight on firing. That means the J needs less firing shrinkage, more drying shrinkage to work with P700.
Testdata
SHAB - Shrinkage/Absorption
| DLEN | FLEN | FWT | BWT | CONE | DSHR | FSHR | ABS | |
| 10 | 94.16 | 87.71 | 39.22 | 40.94 | 10.0 | 5.8% | 6.9% | 4.4% |
| 12 | 94.18 | 86.36 | 37.77 | 37.77 | 10R | 5.8% | 8.3% | 0.0% |
| 8 | 94.04 | 86.65 | 39.7 | 39.74 | 8.0 | 6.0% | 7.9% | 0.1% |
EBCT - Engobe Body Compatibility Test
| MATA | MATB | BNDR | BNFR | BCON | |
| 1 | engobe | H450 | 4.7/450 | 2/450 | 10R |
| 2 | engobe | H570 | .5/570 | .7/570 | 10R |
| 3 | G3954H | G3954J | 3mm/J | 1.5mm/J | 10R |
| 4 | H55O | L3954J | 3.5/H550 | 3.5/J | 10R |
| 5 | P700 | L3954J | 11/J | 0/J | 10R |
XML (to paste into Insight)
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Black Cone 10 Whiteware Engobe Recipe" keywords="For Plainsman H570" id="130962" key="w3Zqsaw1" date="2023-05-28" codenum="L3954J"> <recipelines> <recipeline material="Nepheline Syenite" amount="15.000" tolerance=""/> <recipeline material="Silica" amount="15.000" tolerance=""/> <recipeline material="Ball Clay" amount="57.000" tolerance=""/> <recipeline material="Bentonite" amount="2.500" tolerance=""/> <recipeline material="Mason 6600 Black" amount="10.000" added="true"/> </recipelines> </recipe> </recipes>
Born: 2016-12-12, Modified: 2023-05-28 21:15:53
Variation of Recipe L3954N
Cone 10 Engobe for H550
Code Number Extension
L3954N - 1
Recipe Name Extension
Black
Base Recipe For This Variation
| Materials | Amt |
|---|---|
| Nepheline Syenite | 10.000 |
| Silica | 20.000 |
| OM #4 Ball Clay | 60.000 |
| Bentonite | 2.000 |
| Additions | |
|---|---|
| Mason 6600 | 10.000 |
Total:102.00
|
Si:Al: 5.8:1 5.2 (Molar:4.9) 6.4 Cost 5.03 per kg |
Notes for this variation
We normally use 10% black stain, but have tested lesser amounts down to 5%. Just use as much as you need to get the degree of black you want.
Pictures
L3954N black On L4048A H550
L3954N Black on L4048A H550 Test
Black cone 10R slip fired bar
Testdata
SHAB - Shrinkage/Absorption
| DLEN | FLEN | FWT | BWT | CONE | DSHR | FSHR | ABS | |
| 12 | 92.77 | 85.43 | 43.26 | 43.88 | 10.5R | 7.2% | 7.9% | 1.4% |
EBCT - Engobe Body Compatibility Test
| MATA | MATB | BNDR | |
| 1 | L4050A | L3954N-1 | 15/L4050A |
| 2 | L4048A | L3954N | 10/L4048A |
