Machining Vs Investment Casting
CNC Machining is a manufacturing process in which pre-programmed computer software dictates the movement of factory tools and machinery. CNC stands for computer numerical control which eliminates the restrictions of manual control and results in a high-quality output. Thanks to CNC machining, even the most difficult of three-dimensional cutting tasks can be accomplished in a single set of prompts.
CNC machining is well-known in the industry to be able to deliver components quickly and accurately and is repeatable and capable of achieving precise, high quality finishes. Not only is the machining process different to the casting process but things like cost, lead times, selection of materials and finished product quality can be different too.
What Is Investment Casting?
Also known as lost wax casting, investment casting involves pouring a liquid metal into a hollow ceramic mould. Once the liquid metal has cooled and solidified, it is extracted from the mould cavity. The process, up to the pouring of the metal is what makes the investment casting technique unique and delivers a better surface finish than other casting methods.
When it comes to the production of components with high accuracy, repeatability and integrity, this method is very popular. However it is important to take time to consider your options and so here we explore machining compared to investment casting.
Machining Compared To Investment Casting
Preparation
CNC machining doesn’t require preparatory tooling in the way that casting methods do. This makes it a lower cost option and contributes to quicker turnaround times. Machining can often be used to bridge the gap before high volume production takes place. With a higher volume of production, investment casting offers significant savings in terms of time and labour costs, once the tooling phase has passed, it’s repeatability and consistency is a significant advantage.
Accuracy & Precision
Both CNC machining and Investment casting are known for their precision and accuracy which ensures quality and consistent product output, but when it comes down to manufacturing of highly complex and intricate parts, investment casting wins hands down.
Production Speed
This is where machining comes into it’s own. As an automated process it is much quicker than manual processes, and since there is no tooling to account for, it can be suitable for prototype work and rapid production of smaller volumes. That said, once the tooling for your cast component is finalised, investment casting also offers a quick turnaround.
Cost-Effectiveness
Despite the initial outlay in machinery, CNC machinery can be used 24/7 and by anyone who is trained to use them which means that they soon recoup their investment. Less skilled operatives can operate CNC machines which can reduce the costly risk of human error and also reduce your overheads.
Versatility Of Materials
Investment casting is suitable for a wide range of metals, ferrous and non-ferrous. Stainless steel, copper, aluminium, nickel and titanium are amongst those that can be used in investment casting. Almost any material can be used in a CNC machine depending on the application, in addition to the metals already mentioned, they are also suitable for fibreglass, plastics, foam and wood.
Combining Casting & Machining
One of the reasons why investment casting is a popular choice in the manufacture of metal parts is the fine surface finish that is achievable from this process alone. There is typically no further need for machining, unlike some other casting methods, but in the event that further changes are required, secondary machining can be carried out to the desired finish.
Contact Precision Investment Castings
Looking for enhanced finished castings through CNC machining? Our onsite machine shop enables us to supply fully finished investment castings that are ready for assembly. Whatever type of finish you require, our state-of-the-art and industry leading CNC Machinery will provide what you need to a high standard. For more information, get in touch with our team at Precision Investment Castings today by calling us directly on 0161 925 5160 or use our online contact form to submit your enquiry today.