PT Motorsport is proud to be able to supply genuine Raychem ATUM to our valued customers. (Certificate Of Conformance available on request)
Useful for insulating splices, using as cuffs to end a run of DR-25 or Braid, supporting and strain reliving spliced or repaired wires.
Sizes for as supplied and recovered (shrunk).
One size per line.
Choosing the right ATUM for your project.
To select the correct size ATUM for you project, always select the largest size of the tube that will snugly fit onto the substrate. This will maximise the installed wall thickness and provide better protection. Ensure not to force fit the size for the application.
Getting the best result
To get the best result consider the following
- Cut your ATUM to length with sharp, sturdy scissors that are not serrated and can cut the ATUM in one cut.
- Cut the ATUM perpendicular and square.
- Measure the length of ATUM to be used on your branches, and ensure all branches have the same length ATUM cuffs to ensure a professional look. 25mm is a good cuff length to start with. Maybe longer for larger diameters.
- Recover the ATUM fully, it can take longer and slightly more heat that you could be expecting, dimpled surface on recovered ATUM indicates incomplete recovery.
- For larger diameters of ATUM, begin recovering the ATUM from the middle and work your way out, recovering all the way around as you go, if you heat up just one side, it can turn inside out, ruining the ATUM.
- The ATUM Glue is very hot when it’s recovering, it will stick to your skin and burn you.
- Don’t touch the ATUM until it’s fully cooled, fingerprints and tools will leave a lasting impression on it, spoiling it smooth appearance. Use a tool like the Knipex Telephone pliers to pinch the end without leaving a texture.
- Consider the order of installing and recovering the ATUM, will you be able to get the right size ATUM past other features on the harness after you’ve completed branching or terminating? You might need to install your main trunk branch ATUM before you start branching your harness.
The best tip though, make a test piece! Get your process and heat source dialed in. The small investment in some wire offcuts and 3cm of ATUM will be worth it before your spoil your project!
Have more questions or something to add?
Let us know! We love to chat about wiring harness materials and construction.
SCL Technical Documentation
ATUM is a semi-flexible, adhesive-lined, heat shrinkable tubing that provides moisture resistance, strain relief, and electrical insulation for electrical splices, terminations, breakouts, and mechanical connections. ATUM is constructed as a dual-wall tubing. The outer wall is a semirigid, polyolefin, while the inner wall is a melt able polyolefin that flows with the application of heat. Heating ATUM shrinks the outer jacket and melts the inner “encapsulant” wall to flow and fill surface irregularities. While still hot, the tubing can be pinched and blocked to form a wire breakout. ATUM provides a splash-resistant, moisture-resistant covering suitable for many applications. ATUM also performs satisfactorily if briefly exposed to common solvents or chemicals. The installed tubing provides rugged protection against abrasion, vibration, and flexing. Due to its 4:1 shrink ratio a wide range of applications can be accommodated with only a few sizes of ATUM tubing.