Resources
ARCO® Silicone has over 100 years experience in custom extrusions. We offer short-runs, quick turn arounds, and prototyping services.
While a flame-resistant 30 durometer silicone band may look like a simple band to some, it takes a trained and knowledgeable silicone professional to know the difference between the two.
For the most part, a standard silicone band could possibly look and feel virtually the same as a highly-engineered product with one exception – it will not perform the same – and that’s what matters the most.
Take a moment to look over some of the resources we’ve provided below. We have found this info to be useful to our clients as well as anyone who is interested in learning more about the silicone extrusion process. We will add to this page as new developments emerge, so check back often!
As always, we are here to help. If you have a question or if you’d like to discuss your silicone needs with us, please feel free to fill out the “contact us” form at the bottom of the page.
RMA TOLERANCE TABLES
The Rubber Manufacturers Association (RMA) has developed tolerance tables with ranges to provide communication between user and provider across a wide range of industries. The following RMA Tolerance Tables are specifically for extruded cross-sectional rubber profiles and cut-to-length unspliced parts. These tables help customers and manufacturers to identify and understand critical dimensional requirements, as well as the associated achievability and cost. Projects with closer tolerance demands during the manufacturing process will incur higher costs, so it’s very important to know this information up front. When your project demands close tolerances please specify in the drawings or in the quote request.
Keep in mind that these are standard tolerances, but custom tolerances are always available to better fit your needs.
For Extruded Cross-Sectional Parts
The Rubber Manufacturers Association (RMA) has developed tolerance tables with ranges to provide communication between user and provider across a wide range of industries.
This RMA Tolerance Table is specifically for Extruded Cross-Sectional rubber profiles. It helps customers and manufacturers to identify and understand critical dimensional requirements, as well as the associated achievability and cost. Projects with closer tolerance demands during the manufacturing process will incur higher costs, so it’s very important to know this >information upfront. When your project demands close tolerances please specify in the drawings or in the quote request.
Tolerances are for outside diameters (O.D.), inside diameters (I.D.), wall thickness, width, height, and general cross sectional dimensions or extrusions.
Keep in mind that these are standard tolerances, but custom tolerances are always available to better fit your needs.
Millimeters
| RMA CLASS | 1 High Precision | 2 Precision | 3 Commercial | |
|---|---|---|---|---|
| Dimensions (mm) | RMA DRAWING DESIGNATION | |||
| E1 | E2 | E3 | ||
| Above | Up To | ± | ± | ± |
| 0 | 1.5 | 0.15 | 0.25 | 0.40 |
| 1.5 | 2.5 | 0.20 | 0.35 | 0.50 |
| 2.5 | 4.0 | 0.25 | 0.40 | 0.70 |
| 4.0 | 6.3 | 0.35 | 0.50 | 0.80 |
| 6.3 | 10 | 0.40 | 0.70 | 1.00 |
| 10 | 16 | 0.50 | 0.80 | 1.30 |
| 16 | 25 | 0.70 | 1.00 | 1.60 |
| 25 | 40 | 0.80 | 1.30 | 2.00 |
| 40 | 63 | 1.00 | 1.60 | 2.50 |
| 63 | 100 | 1.30 | 2.00 | 3.20 |
Inches
| RMA CLASS | 1 High Precision | 2 Precision | 3 Commercial | |
|---|---|---|---|---|
| Dimensions (in) | RMA DRAWING DESIGNATION | |||
| E1 | E2 | E3 | ||
| Above | Up To | ± | ± | ± |
| 0 | 0.6 | 0.006 | 0.010 | 0.015 |
| 0.6 | .10 | 0.008 | 0.014 | 0.020 |
| .10 | .16 | 0.010 | 0.016 | 0.027 |
| .16 | .25 | 0.014 | 0.020 | 0.031 |
| .25 | 1.39 | 0.016 | 0.024 | 0.039 |
| .39 | .63 | 0.020 | 0.031 | 0.051 |
| .63 | .98 | 0.027 | 0.039 | 0.063 |
| .98 | 1.57 | 0.031 | 0.051 | 0.079 |
| 1.57 | 2.48 | 0.039 | 0.063 | 0.098 |
| 2.48 | 3.94 | 0.051 | 0.079 | 0.126 |
For Cut to Length Unspliced Extrusions
Millimeters
| RMA CLASS | 1 Precision | 2 Commercial | 3 Non-Critical | |
|---|---|---|---|---|
| Length (mm) | RMA DRAWING DESIGNATION | |||
| L1 | L2 | L3 | ||
| Above | Up To | ± | ± | ± |
| 0 | 40 | 0.7 | 1.0 | 1.6 |
| 40 | 63 | 0.8 | 1.3 | 2.0 |
| 63 | 100 | 1.0 | 1.6 | 2.5 |
| 100 | 160 | 1.3 | 2.0 | 3.0 |
| 160 | 250 | 1.6 | 2.5 | 4.0 |
| 250 | 400 | 2.0 | 3.2 | 5.0 |
| 400 | 630 | 2.5 | 4.0 | 6.3 |
| 630 | 1000 | 3.2 | 5.0 | 10.0 |
| 1000 | 1600 | 4.0 | 6.3 | 12.5 |
| 1600 | 2500 | 5.0 | 10.0 | 16.0 |
| 2500 | 4000 | 6.3 | 12.5 | 20.0 |
| 4000 | 0.16% | 0.32% | 0.50% | |
Inches
| RMA CLASS | 1 Precision | 2 Commercial | 3 Non-Critical | |
|---|---|---|---|---|
| Length (in) | RMA DRAWING DESIGNATION | |||
| L1 | L2 | L3 | ||
| Above | Up To | ± | ± | ± |
| 0 | 1.6 | #0.03 | #0.04 | #0.06 |
| 1.6 | 2.5 | 0.03 | 0.05 | 0.08 |
| 2.5 | 4.0 | 0.04 | 0.06 | 0.10 |
| 4.0 | 6.3 | 0.05 | 0.08 | 0.13 |
| 6.3 | 10.0 | 0.06 | 0.10 | 0.16 |
| 10.0 | 16.0 | 0.08 | 0.13 | 0.20 |
| 16.0 | 25.0 | 0.10 | 0.16 | 0.25 |
| 25.0 | 40.0 | 0.13 | 0.20 | 0.40 |
| 40.0 | 63.0 | 0.16 | 0.25 | 0.50 |
| 63.0 | 100.0 | 0.20 | 0.40 | 0.63 |
| 100.0 | 160.0 | 0.25 | 0.50 | 0.80 |
| 160.0 | 0.16% | 0.32% | 0.50% | |
This RMA Tolerance Table is specifically for Cut to Length Unspliced Extrusion profiles. It helps customers and manufacturers to identify and understand critical dimensional requirements, as well as the associated achievability and cost. Projects with closer tolerance demands during the manufacturing process will incur higher costs, so it’s very important to know this information up front. When your project demands close tolerances please specify in the drawings or in the quote request.
Due to the stretchability and compressibility of silicone rubber, the cut length measurements are hard to calculate. On top of this, temperature plays a key role in the amount of stretch that is achievable so it becomes necessary to allow the extruded product to fall back to room temperature before an accurate measurement can be taken.
Tolerances are for outside diameters (O.D.), inside diameters (I.D.), wall thickness, width, height, and general cross-sectional dimensions or extrusions.Keep in mind that these are standard tolerances, but custom tolerances are always available to better fit your needs.
