Akrovest Platinum Instructions

Take a stack of five paper towels, folded double as in a towel dispenser, and wax the sprue of the wax tree to the center of the top paper towel.(A pin cushion type setup can also be done in the same manner).

A flat piece of corrugated cardboard can be used under the towels as a support for handling and moving the flask.

Select a proper size flask for the tree being processed. Place it around the tree with uniform spacing and wax it to the top towel.

Use masking tape to provide a 1-inch extension above the top of the flask.

Note: It is not necessary to use a liner around the inside of the flask. If one is used, it should be absorbent, and approximately ¼” of the flask should be left bare at each end.

The phosphoric acid binder is supplied as a concentrate which is diluted with water (de-ionized or distilled).

The binder concentrate and water volumes should be measured carefully. The proportion is 3 parts concentrate to 77 parts water by volume. Always add the acid concentrate to the water.

The binder solution can be made as needed for each mix, or else a large quantity can be made and stored in a plastic bottle with a tight fitting plastic cap.

Use a heavy-duty mechanical mixer such as a Hobart, Model N-50, or equivalent.

The liquid/powder ratio is 30 ml/100 grams. Consult the accompany table for quantities for various size batches.

Add the binder solution to the mixer bowl. If the solution is being made up for each mix, add the water to the bowl first, then the acid concentrate.

Weigh out the required amount of investment and add half of it to the mixing bowl. Stir by hand to mix it in.

Mount the mixing bowl on the Hobart Mixer and stir at #1 speed setting.

Add the balance of the investment to the bowl a little at a time with continued stirring. (Having started with an 800-gram batch, for example, it should take about 5 minutes to get it all mixed in.) At this point, the mixer can be stopped, if necessary, and a spatula used to push any unmixed dry investment into the slurry.

After all the investment is mixed in, increase the Hobart Mixer speed to the #2 setting and continue to mix for at least 10 minutes (total time from the start of mixing).

Note: Longer mixing times cause the mix to become more fluid, and this can be done in instances when greater fluidity would be desirable.

Vacuum the mix in the bowl, and continue vacuuming for 1 to 1 ½ minutes after the mix comes to a boil.

Pour the investment slurry into the flask without hitting the patterns. Fill to the top edge of the flask.

Vacuum the slurry again in the flask and continue for 1 to 1 ½ minutes after it comes to a boil. (The extension on the flask will accommodate this action.)

Allow the flask to remain undisturbed overnight on the stack of paper towels (usually 18 to 20 hours).

Next Day: Remove the extension from the top of the flask and trim the investment flush with the top of the flask. Remove the paper towels from the bottom of the flask.

Investment Powder Binder Conc. Water Total Solution


	Zero-D Products, Inc. \| home Investments \| Akrovest Premium Instructions \| Akrovest Platinum Instructions Akrovest Platinum Instructions Flask Preparation Take a stack of five paper towels, folded double as in a towel dispenser, and wax the sprue of the wax tree to the center of the top paper towel.(A pin cushion type setup can also be done in the same manner). A flat piece of corrugated cardboard can be used under the towels as a support for handling and moving the flask. Select a proper size flask for the tree being processed. Place it around the tree with uniform spacing and wax it to the top towel. Use masking tape to provide a 1-inch extension above the top of the flask. Note: It is not necessary to use a liner around the inside of the flask. If one is used, it should be absorbent, and approximately ¼” of the flask should be left bare at each end. Binder Solution The phosphoric acid binder is supplied as a concentrate which is diluted with water (de-ionized or distilled). The binder concentrate and water volumes should be measured carefully. The proportion is 3 parts concentrate to 77 parts water by volume. Always add the acid concentrate to the water. The binder solution can be made as needed for each mix, or else a large quantity can be made and stored in a plastic bottle with a tight fitting plastic cap. Investing Use a heavy-duty mechanical mixer such as a Hobart, Model N-50, or equivalent. The liquid/powder ratio is 30 ml/100 grams. Consult the accompany table for quantities for various size batches. Add the binder solution to the mixer bowl. If the solution is being made up for each mix, add the water to the bowl first, then the acid concentrate. Weigh out the required amount of investment and add half of it to the mixing bowl. Stir by hand to mix it in. Mount the mixing bowl on the Hobart Mixer and stir at #1 speed setting. Add the balance of the investment to the bowl a little at a time with continued stirring. (Having started with an 800-gram batch, for example, it should take about 5 minutes to get it all mixed in.) At this point, the mixer can be stopped, if necessary, and a spatula used to push any unmixed dry investment into the slurry. After all the investment is mixed in, increase the Hobart Mixer speed to the #2 setting and continue to mix for at least 10 minutes (total time from the start of mixing). Note: Longer mixing times cause the mix to become more fluid, and this can be done in instances when greater fluidity would be desirable. Vacuum the mix in the bowl, and continue vacuuming for 1 to 1 ½ minutes after the mix comes to a boil. Pour the investment slurry into the flask without hitting the patterns. Fill to the top edge of the flask. Vacuum the slurry again in the flask and continue for 1 to 1 ½ minutes after it comes to a boil. (The extension on the flask will accommodate this action.) Allow the flask to remain undisturbed overnight on the stack of paper towels (usually 18 to 20 hours). Next Day: Remove the extension from the top of the flask and trim the investment flush with the top of the flask. Remove the paper towels from the bottom of the flask. Firing and Burnout Firing Schedule: 180°F 1 hour (average size flask) 250°F 2 hours 350°F 1 hour 550°F 1 hour Fire rapidly to 1,600°F; hold 2 - 2 ½ hours Ingredient Measurements Solution/Ingredients Investment Powder Binder Conc. Water Total Solution Grams (or) lb/oz ml ml ml* 400 14 oz 4.5 115.5 120 800 1 lb. 12 oz 9 231 240 1200 2 lb. 10 oz 13.5 346.5 360 1600 3 lb. 8 oz 18 462 480 2000 4 lb. 7 oz 22.5 577.5 600 *ml = milliliters = cubic centimeters