since 1961

Question:  Does Custom Rubber Products have any standard parts I can buy off the shelf?

Answer:  No. Custom Rubber Products is strictly a custom molder producing molded parts to the customer’s furnished drawings and specifications.  All the tooling in our possession belongs to our customers and we cannot manufacture products for any customer out of another customer’s tooling.

Question: Does Custom Rubber Products have any minimum order requirements?

Answer: Yes. Our minimum order varies based upon mold, process and operations being performed. Therefore, each item is reviewed individually.

Question:How does one begin working with Custom Rubber Products?

Answer: From your first contact with Custom Rubber Products, you will experience a difference - a difference that reflects our commitment to customers, even before they are customers. Superior technical competence is something you will experience right from the start. It begins with our sales organization and continues throughout the company. Our design engineering and process engineering team is robust. At every step along the way you will find engineers working for you. Getting started can be as simple as a contact with our Sales department. If you have more detailed information and wish to submit a Request for Quote, we'll help you develop it into a finished product. If you have CAD design files, we make it easy for you to transfer those files for our review, too.

Question: What CAD drawing formats can you interpret?

Answer: Custom Rubber Products has electronic file transfer capabilities to receive customer drawings in AutoCAD 2002 (.dxf and .dwg) and SolidWorks directly into our computer systems. You may even e-mail Adobe (.pdf) format drawings and compressed (.zip) files or fax paper copies. We can help with your critical prototyping and small volume production needs. Our engineering staff can help with selecting the right process and mold that fits your needs.

Question: How much is it going to cost for a mold and parts?

Answer: That is difficult to answer because each part is quoted individually and based on a customer furnished drawing with specifications. No two parts are alike in weight, size, shape, function, complexity of design, material, etc. All parts require either the customer to furnish an existing mold to Custom Rubber Products or to have us manufacture a new mold. We can produce single cavity molds for prototyping or small run production and/or multi-cavity production molds. We will normally quote a wide variety of mold sizes.

Question:  How do I choose a rubber type (polymer/elastomer)?

Answer:We have years of experience in recommending a particular polymer or type of rubber to customers.  It is always based upon their specific application.  Let us know the environment, including temperature, media exposure and other applicable characteristics required.  We will be happy to make our best recommendation of a material from one of hundreds of formulas or develop a specific formulation for your particular application.

Question:  What is the standard lead-time on parts and molds?

Answer:  Lead times for parts vary upon the size of the order, availability of raw materials, and production scheduling.  Normally, we are able to produce a product within 4 to 5 weeks and can sometimes produce partials much sooner to get customers out of scheduling conflicts.  Again, this is based on our production scheduling.  When new molds are made, the time to produce the mold and First Article Samples varies from a minimum of 3 to 5 weeks for a simple prototype mold up to 10 to 12 weeks for high cavitation hardened steel complex production molds. Typically, 6 to 8 weeks covers most mold order lead times and production can be scheduled to commence as soon as the customer has approved the First Article Samples.

Question:  Who owns the mold?

Answer:  All of the molds used by Custom Rubber Products to produce parts for specific customers are owned by those customers.  If you do not already have an existing mold, we will work with you in creating a mold type for your particular application.

Question:  What are molds made from?

Answer:  Most injection molds are machined from pre-hardened tool steel or stainless steel.  Depending upon part size and configuration, the cavity area may be tool steel inserted into a mold base.  Transfer and compression molds are primarily pre-hardened 4140 series steel up to 15” in diameter, but are sometimes made at a lower cost from 8620 steel, depending upon anticipated production volume. Molds greater than 15” in diameter are made from ASTM A36 or J45 steel.  Prototype molds are normally 7075 aluminum.

Question:  What about tool design and manufacture?

Answer:   Our in house design abilities guarantee a better tool design. Proper tool design is the key to ensuring a better quality part and an optimal manufacturing process. These are both important for long term success.  We support long term relationships with local tool vendors to manufacture production molds. Our engineering staff is both capable and skilled in CAD/CAM software.

Question:  What is an elastomer?

Answer:  An elastomer is a material that has the property of being elastic with resilience or memory sufficient to return to its initial shape after major or minor distortion within a reasonably short period of time.  This property makes rubber materials excellent for sealing applications where its flexibility is highly important.

Question:  What is the term “vulcanization”?

Answer:  A thermosetting reaction involving the use of heat and pressure, resulting in greatly increased strength and elasticity of rubber-like materials. Thermoset polymer resins are transformed into vulcanized rubbers by cross-linking.  Energy and catalysts are added that cause the molecular chains to link into a rigid, 3-D structure.  A thermoset material cannot be melted and re-molded after it is cured.  Thermoset materials are generally stronger than thermoplastic materials.  They are also better suited to high temperature applications and are not easily recyclable like thermoplastics, which can be melted and re-molded.

Question:  What are elastomer cost comparisons?

Answer: The actual costs will vary with polymer grade, filler level, and specialty ingredients. This is meant only to be a guide for assistance. If you have specific questions, please contact us.  We will be glad to help you further. Cost comparison is a ratio to the lowest cost elastomers. The following table can be used as a general guideline:

Question:  What is shrinkage?

Answer:  Shrinkage is defined as the difference between corresponding linear dimensions of the mold and of the molded part, both measurements being made at room temperature.  All rubber materials exhibit some amount of shrinkage after molding when the part cools.  However, shrinkage of the compound is also a variable in itself and is affected by such things as material specification, cure time, temperature, pressure, inserts, and post cure.  The mold designer must determine the amount of shrinkage for the selected compound and incorporate this allowance into the mold cavity size.  Even though the mold is built to anticipate shrinkage, there remains an inherent variability which must be covered by adequate dimensional tolerance.  Shrinkage of rubber is a volume effect.  Complex shapes in the molded product or the presence of inserts may restrict the lineal shrinkage in one direction and increase it in another.  The skill of the rubber manufacturer is always aimed at minimizing these variables, but they cannot be eliminated entirely.

Question:  What about secondary operations?

Answer:  If your project requires secondary operations to make it more complete and ready for the next step in your operation, Custom Rubber Products is equipped.  We have the ability to accurately machine rubber and/or phenolic parts.  In addition to machining, we are equipped to perform die cutting, slitting, roller grinding, and even precision lip seal cutting.  If you require special packaging, we are ready to provide custom bagging, boxing, or labeling.  These secondary operations performed by us will add to the efficient flow of your product and lower your overall costs.  Don't forget to consider it as part of what Custom Rubber Products can do for you.