Radius Square Tube

Radius Square Tube

Blended radius corners and a slight convex side provide greater strength than standard round tubing. This great alternative to box section tubing is popularly used for baluster railings and furniture.

A popular variation on square steel tubing, Timeless’s unique radius square tube boasts a beautifully contoured shape. The refined design looks and feels better than square tube and conventional box tubing, making it an excellent alternative to standard square shaped tube.


  • Blended radius corners and a slight convex side provide impressive strength integrity
  • Elegant alternative to standard box section tubing
  • Typically used for spindles, baluster railings, grab rails and furniture
  • Lighter and more cost-effective than solid bars
  • Stainless steel radius square tube available in 9 existing sizes — from 17x17x1.5mm to 88x88x2mm

Smooth, ‘softened’ corners for decorative applications and easy maintenance

Due to its appealing softened corners and the range of available sizes, this tubing is ideal for balustrades and handrails. The two largest tube sizes are suitable for newel posts (commonly known as staircase spindles). Our engineers have formed this tubing from ‘marine grade’ 316L stainless steel to be used as grab rails on luxury tender boats; it is both elegant and ergonomically viable as an important safety feature onboard world-class sea-faring craft.

Radius square tube is also an ideal choice for medical furniture, food and drink manufacturing equipment and laboratory equipment, when a wipe-clean / wash-down environment is essential. Unlike angular box tubing, water and residue will glide off the contoured edges of this practical tube profile.


Structurally strong steel square tubing

Our stainless steel radius square tubing has impressive strength integrity. Timeless’s robust deflection tests show that when tested on the flat side (the ‘flush’), the radius square tube is 54% stronger in terms of its deflection capacity than its round tube equivalent. Its strength, coupled with its symmetry, means that our radius square steel tube is an ideal candidate for bending, should you require a large radius bend for your application.

Stainless steel,  aluminium, titanium or copper-based square tubing

We can form this specialist tube profile from all of the metals that we form from here at Timeless. Stainless steel 304L and 316L are our most popular materials as they offer high durability and a range of finishes. Find out more about the properties of each different metal type, or call us about your project and we can talk you through the different metals and finishes available, as well as the other fabrication services that we offer.


  • Staircases
  • Balusters
  • Spindles
  • Newels
  • Balustrades
  • Balconies
  • Railings
  • Furniture
  • Radiators
  • Lighting
  • Door handles
  • Kick rails
  • Decorative shrouds
  • Street signs
  • Queue management systems
  • Metal stair nosing
  • Food and drink manufacturing equipment


Radius Square Tube Specifications.

The image above shows how dimensions are detailed (for example, 65mm x 27mm x 2mm).

Our stainless steel and aluminium 5083 oval tube profiles are sold in lengths of 5.8m (the manufacturing process reduces the standard 6m length by 0.2 metres).

Below is a table of the available stainless steel tube sizes that we have in our existing range for this shape of tube. Can’t see the tube sizes you need? Contact us to discuss your project requirements – we may be able to fabricate some custom-made sized tubing. Or download our sizing PDF, which contains sizing information for existing aluminium and brass tubing too, as well as all stainless steel sizes.

Upon request, we will be able to find out wall thickness tolerances from our metal suppliers. Typically the tolerance levels of wall thickness are extremely minimal and any small variations in thickness do not affect further fabrication or the end application. However, it is important to let us know if the tolerance is critical to the application before you place an order. For example, if the shaped tubing component needs to go inside another component, or if the tubing has to house a component, any variation in wall thickness could be critical. Ask us about tolerances.

Radius Square Stainless Steel Tube Sizes

Tube Size1.5mm
(Wall thickness)
(Wall thickness)
17mm x 17mm---
23mm x 23mm---
28mm x 28mm
34mm x 34mm
45mm x 45mm
66mm x 66mm
88mm x 88mm

Contact Us

For expert advice, quotes and free samples

*** We have a minimum order quantity of 1 length (usually 5.8m, depending upon metal used). Orders of 5 lengths or under incur a £50 set-up fee. We DO NOT work with mild steel.***


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