Family Mold
Family Mold is a series of different part molds contained in one main mold. This makes it possible for you to manufacture several parts of the same material in a single cycle.
It is worth noting that we can’t produce identical parts using Family Molds.
This can allow you to incorporate different variations in design when handling a specific assembly. This facilitates a streamlined production process with flexibility in terms of part design variation.
Process of Creating Family Molds
Due to modern technology, it has become very easy to create your ideal family mold. The steps include;
- You can design a 3D Mold and send it to your manufacturer as a CAD file or have them design it for you.
- The manufacturer will then review the Mold and factor in any tooling process that may be involved.
- Once the design is approved, the manufacturer begins constructing the Family Mold
- You can examine the sample of the part before they proceed to the production stage
- The Family Mold is finally produced and is ready for part production
Merits and Demerits of Family Molds
Family Molds come with their fair share of pros and cons. Let’s analyze them by starting with the merits.
Improved Efficiency – The production process is greatly improved whenever Family Mold is applied. The fact that it is possible to manufacture various parts simultaneously in a single cycle means the production time is reduced.
Improved Cycle Time – When hot runner molds are used in in Family Molds, the cycle time is greatly improved. This due to the reduced cooling and ejection times since all parts remain molten simultaneously.
This means that you can produce more parts in less time leading to a better operational efficiency.
Cost-Effective – When you are able to produce different parts at the same time, the production cost is greatly reduced. This is in contrast to applying various molds when producing different parts for assembly.
Therefore, that fewer machines will be required in addition to having reduced man power. Post production is also improved since assembling the separate parts is no longer necessary and fewer machines will be required.
Enhanced Quality – The fact that consistency is guaranteed means the quality parts remains constant. This is because all parts are made from the same material under the same production conditions.
This is very vital especially in instances where aesthetic uniformity determines the quality of the part produced.
Easy Ordering – It’s normally complicated when you want to place orders for several molds for one project. This is because the lead times and mold design are different.
Family Mold simplifies all these when you opt for t from the word go. This is because of the one-off production process.
Easy Prototyping – Family Molding is very convenient for producing part prototypes because a single mold is used to produce everything. This greatly reduces the pre-production cost.
We can summarize the demerits of the Family Mold as follows;
Poor Part Balancing – When filling the Family Mold with the mold material, it is challenging for the material to reach all the individual cavities. This because they contain different geometries and may result in part warpage and other defects.
Pre-Requisites Of Family Molds
Setting up Family Molds is usually expensive initially but eventually the gains are worth the wait. This is because it takes a longer development time owing to the complex nature of their design.
Such parts need to follow a pre-defined criteria if the best standards have to be met. Let’s take a look at some of the pre-requisites required.
Similar Material And Color – As you choose material for this manufacturing process, you should ensure they have the same color and quality. This is because the whole process takes place in a single cavity and heating the material requires uniformity.
Equal Volume And Size – Filling the Family Mold has to happen in a single cycle. This means that there is a possibility of underfilling occurring when the parts have different shapes or sizes.
Another defect that occurs due to this is flash molding.
Family Molds Vs Multi-Cavity Molds
When we want to analyze these two molds, we have to look at each individually to have a better understanding. In brief, we can summarize them as follows:
Multi-Cavity Mold – Usually, the multi cavity molds will ensure improved production rates. Some of its benefits include a reduced cycle time, flexible part designs and reduced part cost.
Others are good repeatability in part quality with the option of optimizing the equipment. However, the downside of this mold is its high complexity that come with flash and parting line issues.
Family Mold – These molds have the ability to manufacture very many parts within a single cycle. These Molds have a single mold cavity compared to the Multi-Cavity Mold.
They make up for that by enabling the production of very many related parts within a single cycle. This makes it easy to have design variations when molding parts for specific assemblies. Part changeovers are simplified in addition to improved efficiency at lower costs.
Main Differences – It is evident that both molds have differences in terms of their application and production requirements. Let’s now take an in-depth analysis of the two cavities:
Efficiency and Volume of Production – The design of the Family Mode makes it possible to manufacture several part components in a single cycle. This is very convenient when for large scale manufacturers producing very many identical parts.
It is ideal for parts that would otherwise require assembly after processing.
Maintenance And Tooling – When comparing the two in terms of maintenance and tooling, Multi-Cavity Molds have the upper hand. This is because you only need to clean and repair them occasionally.
On the contrary, the maintenance and tooling requirements is a bit complicated based on their design. This is because you would need to perform regular adjustments tool wise in addition to varying the design.
Cost – Increase in production volume means a decrease in overall part cost. The cost per part is very low in Multi-Cavity Molds since many parts are produced per cycle.
Family molds reduces the cost of having several different modes for a specific assembled part.
Quality – Having a consistent single Mold guarantees the quality of part production. Variations are also greatly reduced due to their excellent cooling characteristics.
Factors Affecting Family Mold Production
Cost of producing various parts on the same cycle greatly influence the production of any Family Mold. More parts implies an automatic cost reduction. However, this proves much cheaper compared to producing individual parts and assembling them.
The process of filling the Family Mold is majorly influenced by how the Mold is balanced. An increase in parts wall thickness may lead to dimensional problems. This may affect the aesthetic properties of the final product.
All the parts in a Family Mold are literally conjoined. This is because all the parts produced in a single cycle have to be perfectly aligned to each other.
Family Molds are normally preferred when producing part sizes that require minimal run sizes. This usually ranges for 50,000 or less parts that multi-cavities cannot produce due to financial constraints.
All the produced parts need to be as close possible in terms of their physical size and other feature related to their general design. There are designs that have complicated cores meaning it is hard to physically fit them.
In-Mold Assembly Using Family Molds
When using In-mold Assembly for Family Molds, production is great improved despite it being sophisticated. Normally they are applied in situations where the overall production is not so much due to their complicated design.
In in-Mold Assembly, different designs that are identical are molded in twos or multiples of two. This occurs on opposite sides of each individual mold.
Assembly of the parts can be done manually when they are on their ejection phase. Alternatively, automation method can be applied.
However, automation requires that the parts should be ejected directly to conveyors. Hence require controlled circumstances to be efficient.
Therefore, assembling consumes a lot of time. In contrast, their overall production means time is saved based on any additional set up that may be included in future.
Design Considerations For Family Molds
When using Family Molds, it is advisable that you focus on developing the mold. but due to their complex design, you have to factor in special considerations.
They include but not limited to:
Cooling System
Every good cooling system is the surest way of having a uniformly cooled Family Mold. This goes a long way in improving the productivity with a reduced cycle time.
Cooling channels and inserts are a great way of achieving this. They help prevent defects such as part warpage.
Cavity Balancing
For the filling to be consistent throughout the cavity, you must balance the Family Mold with precision. You will have to adjust the sizes of your gates in addition to the cooling system.
This will prevent any twists and turns that may occur during part processing. The part will cure uniformly.
Mold Material
The material used for part manufacture has a great impact on its design. For the part to last longer and be durable, you need to use the appropriate material based on its application.
The Mold should be able to withstand very many production cycles. This can be achieved by having a good mold steel with an excellent surface coat.
Parting Line
Since very many layers are involved with different designs, the parting line has to be properly placed. This is in order to prevent defects like parting line mismatch.
Applications Of Family Molds
It is mostly applied for part production having complex designs. Such parts are usually related and should be assembled at a go.
When you have a part that requires uniform material with a specific volume and size, the family Mold is your best production bet. It is also convenient for parts that require low production and need a small turn-around time.
More Resources:
Injection Molding – Source: Wikipedia
Multi-cavity Molds – Source: ICOMOLD