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Modified: 2022-04-12 10:28:39
Plainsman Cone 6 Ravenscrag Slip glaze. See more at ravenscrag.com.
Material | Amount |
---|---|
Ravenscrag Slip | 60.00 |
Calcined Alumina | 10.00 |
Dolomite | 10.00 |
Ferro Frit 3134 | 20.00 |
Added | |
Manganese Dioxide | 4.00 |
Rutile | 5.00 |
Illmenite Granular | 0.30 |
109.30 |
Note: For use as a straight glaze We are recommending GA6-F Alberta Slip oatmeal glaze instead, it looks better and has a better melt. Alberta Slip is already a stained material, so less colorants are needed to make darker colored glazes. Go the http://albertaslip.com.
However, as a second layer over other more fluid melt glazes, this can work well. Be sure not to put it on too thick.
We have had a report of this leaching. This is credible because of the 10% calcined alumina in this recipe, only a little of that goes into solution in the melt as Al2O3 because it is high refractory (it is added to achieve matteness here). The significant colorant addition is also a concern. We are working to use the titanium/stain mechanism to create a similar appearance (e.g. the way we do with red stain in G3939A).
For mixing instructions please see the master recipe, GR6-A.
An illmenite colored glaze (GR6-H) at cone 6 oxidation
At various thicknesses on M340, M370, P300. Fired at cone 6 oxidation using the C6PLST firing schedule.
For speckle add granular manganese (adjust the percentage to get the desired speckle density, start at 0.25%). Since the manganese particles are very heavy, and thus want to settle out, the glaze slurry should be thixotropic and stirred before each dip.
The underglaze is G1214M cone 6 black (adds 5% Mason 6666 black stain). Overglaze left: GR6-H Ravenscrag Oatmeal. Overglaze right: GA6-F Alberta Slip oatmeal. Both produce a very pleasant silky matte texture (the right being the best). Both layers are fairly thin. In production it would be best to spray the second layer, keeping it as thin as possible. It is also necessary to adjust the ratio of raw to roasted Alberta or Ravenscrag Slips to establish a balance between drying hardness but not too much drying shrinkage (and resultant cracking).
The black recipe was made using G1214M with 5% Mason 6666 stain. The oatmeal overlayer is 50% the thickness of the black. The more fluid under-black comes through leaving islands and vertical rivulets of the stiffer oatmeal. Good control of the glazing process is needed to get consistent results using this approach.
This is GR6-H Ravenscrag Slip oatmeal over G1214M black on porcelain at cone 6 oxidation to create an oil-spot effect. Both were dipped quickly.
Firing Schedules |
Plainsman Cone 6 Electric Standard
Used in the Plainsman lab to fire clay test bars in our small kilns |
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Typecodes |
Ravenscrag Slip Recipes
Recipes based on Ravenscrag Slip from Plainsman Clays. |
Typecodes |
Medium Temperature Glaze Recipes
Normally fired at cone 5-7 in electric kilns. |
Recipes |
GR6-A - Ravenscrag Cone 6 Clear Glossy Base
This Plainsman Cone 6 Ravenscrag Slip base is just the pure material with 20% added frit to make it melt to a glossy natural clear. |
Recipes |
GA6-F - Alberta Slip Cone 6 Oatmeal
Plainsman Cone 6 Alberta Slip based glaze. It can be found among others at http://albertaslip.com. |
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