American. Acrylic Works
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Choosing wall thickness

Thicker walls add strength and rigidity. Thinner walls save weight and cost. Here's how to decide.

Wall thickness options

American Acrylic Works carries cast acrylic tubes with wall thicknesses ranging from 0.125″ (⅛″) to 0.500″ (½″). Not every OD is available in every wall — browse our tube catalog to see what's in stock for your diameter.

General guidelines

Thin walls: 0.125″ – 0.187″

  • Best for: display tubes, light diffusers, decorative columns, candle molds
  • Lightweight and cost-effective
  • Not suitable for pressure or structural loads
  • More flexible at larger diameters — may need support for long spans

Medium walls: 0.250″

  • The most common general-purpose wall thickness
  • Good balance of strength, clarity, and cost
  • Suitable for sight gauges, process piping, aquarium components, structural columns
  • Machines well — enough material to face, bore, or turn without chatter

Thick walls: 0.375″ – 0.500″

  • Maximum rigidity and impact resistance
  • Best for: pressure vessels, structural applications, heavy-duty process equipment
  • More material for machining — useful when boring out custom IDs
  • Heavier — consider shipping weight for long lengths

Factors to consider

Pressure

Acrylic tubes are not rated for internal pressure without engineering analysis. If your application involves pressurized fluid or gas, you need to calculate hoop stress for your specific OD, wall thickness, and operating pressure. Cast acrylic has a tensile strength of approximately 10,000 psi, but a conservative safety factor of 4:1 or higher is standard practice.

For any pressure application, consult an engineer and consider burst testing a sample before committing to production.

Span and support

Longer unsupported spans need thicker walls to resist deflection. A 2″ OD tube with 0.125″ wall will flex noticeably over a 48″ span, while the same tube at 0.250″ wall stays rigid. For vertical columns, the tube's own weight matters less — lateral loads and wind are the concern.

Machining

If you plan to turn, bore, or mill the tube, thicker walls give you more material to work with and reduce the risk of chatter or cracking during machining. A minimum of 0.250″ wall is recommended for lathe work.

Inner diameter

Remember that wall thickness determines your ID: ID = OD − (2 × wall). If you need a specific inner diameter for a piston, liner, or sleeve fit, choose the OD/wall combination that gives you the right ID — or plan to bore it out.

Still unsure?

Email us at sales@americanacrylicworks.com with your application details. We can help you pick the right size.