Here we recommend a certain burnout cycle that is used by a large casting house, however please note that most of our customers uses different burnout and casting process.
In order to have a quality casting, first and foremost, we recommend to follow carefully the specifications provided by the investment brand you are using. These includes:
- Water-powder ratio (use a scale to measure the water and powder)
- Mixing process and time
- Time to leave the flask before inserting in the oven
- Burnout cycle
- Casting and pressure control
Casting quality depends on many factors such as investment powder used, cylinder size, oven efficiency, casting machine but also on the washing process used after printing.
1. Washing the Models
- 3 minutes with clean alcohol (that is minimum 90% pureness).
- Wash 2 minutes with dirty alcohol then dry by blowing air (an air compressor can be used) and then 2 minutes with clean alcohol then dry by blowing air.
- Check the models, if there are uncured resin on the model wash and dry them again.
- The models should not be exposed to alcohol for more than 6 minutes.
- First choice for alcohol; ethyl alcohol is suggested. Otherwise; isopropyl alcohol can be used.
- Models should be casted as soon as possible (within 2 hours is suggested). The models must always be stored in a dark and ideally in a sealed plastic bag.
2. Investment Process
- Instructions (water-powder ratio, mixing process etc.) by the manufacturer of the investment must be followed.
- Must be make sure that the investment gets vacuum very well. The vacuum process must be aplied by vibrating the investment.
- Casting tree should be inserted as far away from the surface of the flask as possible (! Do not put the printed model close to the flask’s wall).
Note: Every steps should be completed by the professional machines. Every detail is essential to get applied correctly.
3. Recommended Fast-Burnout Cycle
- Before inserting the flask into the furnace, the flask must be left to settle for a minimum 3 hours on the ground.
- Preheat the oven to 750 C degrees,
- Place the flask directly in the oven preheated to 750 C degrees.
- Wait 3 hours, then turn the flask upside (see the chart below) and wait another 1 hour.
- Go down to the determined temperature according to the metal you will cast, wait 1 hour and pour the metal.
3. Recommended Normal-Burnout Cycle
- Before insterting the flask into furnace, flask must be left settled for minimum 3 hours.
- In the last step of the cycle; after ramp down to 600 Celsius degrees within 1 hour, the flask should stay in the furnace at 600 Celsius degrees for about 1 hour before pouring the metal.
- Fresh metal should be used to cast. Metals used for many times (more than 3-4) to get casted should not be used.
If there's any way we can be of assistance to guide you through your process please email us via firstname.lastname@example.org and please join our facebook user group here to get some great tips from other users.