Baiting
The pepsin solution was reheated to 37 C to continue to bait the large pieces of hide. The solution was stirred using the magnetic hot plate stirrer.
Vegetable Tanning
The test strips being tanned in different concentrations of oak bark solution were left to continue tanning.
Showing posts with label Baiting. Show all posts
Showing posts with label Baiting. Show all posts
Saturday, July 23, 2011
July 20, 2011
Baiting
The pepsin solution with the test strips was heated to 37 C and stirred with a magnetic stirrer.
Alum Tanning
The piece of hide in the alum tanning solution was removed from the solution, rinsed, and left to dry. It is unclear whether the alum tanning process worked. The hide appears to be more opaque and slightly more dimensionally stable, however it does not appear to have leather-like qualities.
Vegetable Tanning
The piece of hide that was in the 100% oak bark tannin solution was removed from the solution, rinsed and left to dry. The pieces of hide in other concentrations were left in solution to continue tanning.
The pepsin solution with the test strips was heated to 37 C and stirred with a magnetic stirrer.
Alum Tanning
The piece of hide in the alum tanning solution was removed from the solution, rinsed, and left to dry. It is unclear whether the alum tanning process worked. The hide appears to be more opaque and slightly more dimensionally stable, however it does not appear to have leather-like qualities.
Vegetable Tanning
The piece of hide that was in the 100% oak bark tannin solution was removed from the solution, rinsed and left to dry. The pieces of hide in other concentrations were left in solution to continue tanning.
July 19, 2011
Baiting
The large pieces of hide were removed from the distilled water and placed in a baiting solution of 3000 mL of distilled water, 30 g of pepsin, and 30 mL of acetic acid. This solution was heated to 37 C.
Alum Tanning
The test strip was left in the alum tanning solution.
Vegetable Tanning- Oak Bark
The pieces of hide being vegetable tanned were left in solution to continue tanning.
Alum Tanning
The test strip was left in the alum tanning solution.
Vegetable Tanning- Oak Bark
The pieces of hide being vegetable tanned were left in solution to continue tanning.
Saturday, July 16, 2011
July 11, 2011
Baiting
The large test strips were baited for the third time in the pepsin solution at 37 C. After several hours the fat had been removed from the pieces of hide and they were removed from the solution.
Soaking
The large test pieces were put in distilled water to remove the excess pepsin solution.
Debarking
Bark was removed from the oak branches using a draw knife to be used as a vegetable tannin. This bark was placed in distilled water to extract the tannins.
Alum Tanning
The piece of hide in the alum solution was left in solution to continue the tanning process.
Soaking
The large test pieces were put in distilled water to remove the excess pepsin solution.
Debarking
Alum Tanning
The piece of hide in the alum solution was left in solution to continue the tanning process.
Monday, July 11, 2011
July 8, 2011
Dehairing
The two large test strips were removed from the lime solution and the hair was removed from them.
Soaking
The test strips were then added to distilled water to remove excess NaOH.
Baiting
The test strips were added to a solution of 2500 mL of distilled water, 25 g of pepsin, and 40 mL of acetic acid. This solution was heated to 37 C and stirred with the magnetic stirrer on the hot plate. This process continued for 3 hours.
Alum Tanning
The alum paste was left on the test strip.
The alum solution with the other test strip was stirred to recombine the separated layers of the solution.
The two large test strips were removed from the lime solution and the hair was removed from them.
Soaking
The test strips were then added to distilled water to remove excess NaOH.
Baiting
The test strips were added to a solution of 2500 mL of distilled water, 25 g of pepsin, and 40 mL of acetic acid. This solution was heated to 37 C and stirred with the magnetic stirrer on the hot plate. This process continued for 3 hours.
Alum Tanning
The alum paste was left on the test strip.
The alum solution with the other test strip was stirred to recombine the separated layers of the solution.
June 22, 2011
Baiting
The third test strip was again baited at 37 C. After 3 hours of baiting the test strip was removed from the pepsin solution. The hide was now extremely thin, delicate, and translucent. This test strip was then cut in two pieces. One half will be alum paste tanned and the other half will be alum solution tanned.
Pickling
Both halves of the third test strip were introduced to a solution of distilled water and acetic acid. This solution had a pH of 4. This process lowers the pH of the hide in preparation for the acidic tanning process.
Vegetable Tanning.
Although we had originally intended to gradually increase the concentration of the tanning solution to which the second test strip was exposed; the speed at which the test strip absorbed tannins from the solution was more rapid than we had expected. Therefore, we decided to keep the concentration of the tanning solution the same throughout the entire tanning process. I created a new tanning solution of the same concentration by combining 300 mL of distilled water with 100 mL of quercitannic acid solution extracted from oak bark. The second test strip was added to the new vegetable tanning solution and left to sit.
The third test strip was again baited at 37 C. After 3 hours of baiting the test strip was removed from the pepsin solution. The hide was now extremely thin, delicate, and translucent. This test strip was then cut in two pieces. One half will be alum paste tanned and the other half will be alum solution tanned.
Pickling
Both halves of the third test strip were introduced to a solution of distilled water and acetic acid. This solution had a pH of 4. This process lowers the pH of the hide in preparation for the acidic tanning process.
Vegetable Tanning.
Although we had originally intended to gradually increase the concentration of the tanning solution to which the second test strip was exposed; the speed at which the test strip absorbed tannins from the solution was more rapid than we had expected. Therefore, we decided to keep the concentration of the tanning solution the same throughout the entire tanning process. I created a new tanning solution of the same concentration by combining 300 mL of distilled water with 100 mL of quercitannic acid solution extracted from oak bark. The second test strip was added to the new vegetable tanning solution and left to sit.
June 21, 2011
Vegetable Tanning
The second test strip was left in the oak bark solution to continue the vegetable tanning process.
Baiting
The third test strip was baited in the same pepsin solution used on June 20th. The solution was heated to 37C and stirred a magnetic stirrer on a hot plate. The third test strip was baited for approximately 4 hours.
The second test strip was left in the oak bark solution to continue the vegetable tanning process.
Baiting
Tuesday, June 21, 2011
June 20, 2011
Alum Tanning
The alum tanning process did not successfully tan the first test strip. The test strip remained cream colored and rubbery. It was unclear whether the alum tanning process did not work or if the test strip was not properly bated. The third test strip will be used to determine which process did not work.
Vegetable Tanning
The second test strip was left in the vegetable tanning solution. This piece has become deeper in color.
Dehairing
Hair was removed from the 3rd test strip.
The third test strip was soaked in distilled water to remove the sodium hydroxide.
Baiting
6 g of pepsin were added to 600 mL of distilled water and 18 mL of acetic acid. This solution was heated to 37°C. The third test strip was placed in this solution and the hot plate's magnetic stirrer was used to stirr the solution.
Vegetable Tanning
Dehairing
Soaking
Baiting
6 g of pepsin were added to 600 mL of distilled water and 18 mL of acetic acid. This solution was heated to 37°C. The third test strip was placed in this solution and the hot plate's magnetic stirrer was used to stirr the solution.
Thursday, June 16, 2011
June 15, 2011
Alum Tanning
The alum tanning paste was again removed from the first test strip and another layer was applied.
Baiting
The second test strip was baited again. This time, 500 mL of distilled water was mixed with 5g of pepsin and 18 mL of acetic acid (CH3COOH) to reduce the pH of the solution. This solution was heated to 37°C. After several hours the sample was removed from the heat and observed. The fatty layer that had been on the flesh side of the test strip seemed to be mostly removed.
Baiting
The second test strip was baited again. This time, 500 mL of distilled water was mixed with 5g of pepsin and 18 mL of acetic acid (CH3COOH) to reduce the pH of the solution. This solution was heated to 37°C. After several hours the sample was removed from the heat and observed. The fatty layer that had been on the flesh side of the test strip seemed to be mostly removed.
June 14, 2011
Alum Tanning
Alum tanning paste was gently scraped from the fist test strip. A new layer was applied and the strip was placed back in the beaker.
Baiting
The second test strip was placed in a solution of 500 mL of distilled water and 5 g of pepsin and heated to 37°C. After several hours it became clear that the bating process was not working so I will try again tomorrow.
Alum tanning paste was gently scraped from the fist test strip. A new layer was applied and the strip was placed back in the beaker.
Baiting
The second test strip was placed in a solution of 500 mL of distilled water and 5 g of pepsin and heated to 37°C. After several hours it became clear that the bating process was not working so I will try again tomorrow.
Monday, June 13, 2011
June 11, 2011
Baiting
The test strip in the pepsin solution was left in solution to continue digestion of unwanted proteins.
The test strip in the pepsin solution was left in solution to continue digestion of unwanted proteins.
Liming
The second test strip was placed in an NaOH solution of 200 mL of H2O and 2 g of NaOH. The solution had a pH of 10. The test strip was left in solution overnight to loosen the hair.June 10, 2011
Dehairing
The test strip was removed from the HaOH solution and laid flat on the table. NaOH solution was disposed of in a labeled hazardous waste container.
Hair was removed from the hide by running my fingers over the hair applying light pressure. Hair was discarded.
Soaking
The test piece was soaked in distilled water to remove the NaOH. The resulting solution had a pH of 7.5 and was discarded in the same hazardous waste container as the NaOH solution.
Baiting
1g of pepsin was added to 500 mL of H2O and heated to 37°C. Pepsin is an enzyme that digests proteins. In leather tanning, pepsin is used to dissolve unwanted proteins from the animal hide leaving behind tannable collagen in the skin.
Debarking
Bark was removed from oak branches with a draw knife for vegetable tanning.
The bark pieces were placed in distilled water to removed the quercitannic acid from them. Quercitannic acid is the tannin found in oak bark with the formula C76H52O46.
The solution immediately began to turn an amber color. The pH of this solution was 6.5.
The test strip was removed from the HaOH solution and laid flat on the table. NaOH solution was disposed of in a labeled hazardous waste container.
The test piece was soaked in distilled water to remove the NaOH. The resulting solution had a pH of 7.5 and was discarded in the same hazardous waste container as the NaOH solution.
Baiting
Debarking
Bark was removed from oak branches with a draw knife for vegetable tanning.
The bark pieces were placed in distilled water to removed the quercitannic acid from them. Quercitannic acid is the tannin found in oak bark with the formula C76H52O46.
The solution immediately began to turn an amber color. The pH of this solution was 6.5.
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