BULLET CORP BULLET COATING INSTRUCTIONS
PPE REQUIRED WHEN USING BCB COATING.
· Chemical resistant gloves
· Safety glasses,
· Respirator adequate for painting.
EQUIPMENT AND TOOLS YOU WILL NEED:
· BCB Coating Powder
· Acetone (100% Pure - Recommended acetone grades CP, AR and HPCL) or MEK, Methyl Isobutyl Ketone
· Safety gear (PPE).
· Measuring tools.
· Plastic containers (buckets) to tumble bullets in.
· A container (plastic bottle) to mix the coating in.
· Paper towels or waste rags and plastic sheeting to protect bench tops or work areas.
· A well-ventilated working area.
· Flat wire trays or baskets capable of holding the weight of the bullets and withstanding the heat of the oven.
· An oven that can hold set temperature fairly well. You will need to test the ovens ability to hold at set temperature and temperature set accuracy (use external meter with temperature probe to verify alloy temperature accuracy).
· Use clean lead bullets that have not been sized. Wash bullets in acetone before coating.
Solvent mixture 70-90% Acetone mixed with 30-10% Methyl Isobutyl Ketone
15 grams of BCB Coating powder to 100ml of solvent mixture for 3 coats.
20 grams of BCB Coating powder to 100ml to 130ml of solvent mixture for 2 coats.
Let the coating stand for at least 1 hour to properly dissolve the coating.
Shake well before use!
Be careful when you open the bottle for the 1st time as the acetone would have built up pressure in the bottle and needs to be released slowly.
Use 1ml to about 300-350 grams of bullets, bigger bullets might need some more coating to properly coat them.
Our coating will self-dry in 5 mins depending on the ambient temperature. If the coating feels dry to the touch you can bake it. If still wet leave for a few more minutes til its dry to the touch.
If you are using methylated spirits drying time may take longer and can cause flaking if not dried properly.
Bake Temperature: 180 to 190 Degrees Celsius (356 – 374 Fahrenheit).
Bake Time: Approximately 10 Minutes – start the 10 minute timer when the alloy temperature has reached temperature set point - maintain alloy temperature for 10 minutes.
Ovens can vary greatly, so testing is required by user to ensure oven adequacy.
1. Place the bullets in a clean bucket with acetone and wash them properly. You can also tumble them slowly in acetone to wash them. If not properly clean the coating will not bond to the lead and it will flake off.
2. Dry the bullets and place it in the bucket you want to coat in.
3. Apply the coating to the bullets and tumble or agitate as fast as you can without the bullets falling out.
4. As soon as the bucket starts getting dry (an indication that the solvent has evaporated and the sound the bullets make in the bucket change) the coating application is complete, dump them in your tray. If the bullets is Matt and dull the coating has not been applied correctly this is due to the acetone evaporating to fast. Use 10 to 20% Methyl Isobutyl Ketone (Example 90% Acetone and 10% Methyl Isobutyl Ketone) to solve this problem. The bullets must be wet and shiny when the coating has been applied.
5. Gently shake the tray slowly to disperse the bullets evenly in the tray.
6. Leave to dry for 1-5min. If it’s dry to the touch you can place the tray in the oven on the recommended setting.
7. After 10 minutes baking time with alloy temperature between 180 to 190 degrees Celsius, remove the bullets and let it cool down, then repeat the process again starting from point number 3 using the same coating bucket.
8. After the coating has been applied 2 or 3 times, let it cool down and tumble (agitate) the bullets in a clean bucket (do not add anything to the bucket, just the bullets), this will remove any roughness on the surface. (its normal if you do get some colour on the hands as this is all the roughness that has been removed from the surface leaving you with a nice smooth surface)
Buy Tumbler for coating process HERE
OVER BAKING MATTERS
Over baking will not harm the coating. However colours will suffer as over baking will darken the final finish.
TESTING THE BULLETS
1. ACETONE TEST
o Remove one bullet from the batch of bullets you have just baked after they have cooled to room temperature.
o Use a rag or paper towel and moisten with Acetone.
o Gently rub the test bullet back and forth for 30 seconds. With proper curing no coating should be removed from the bullet.
FAILURES CAN BE CAUSED BY:
· Low bake temperature
· Overloaded oven
· Poor heat circulation in oven
· Improper bake time
· Dirty or contaminated bullets
· Using too much coating
· Using of wrong mix ratio
2. SMASH TEST
o Use a suitable hammer to smash the coated bullet with one or more blows.
o Check to see if the coating is flaking off.
o If coating flakes from alloy you have failed this test.
THIS FAILURE CAN BE CAUSED BY:
· Coating being applied to thick
· Overloading oven
· Dirty or contaminated bullets.
· Or combination of all
· Not dry enough from using methylated spirits