Square tubes, also known as carbon fiber box sections, are optimised for high-performance strength and stiffness. With in-built radiused corners and flat sides, they are ideal for building support systems, lightweight frames and structures.
If you've got an idea for square carbon tubing and know your specifications, choose your specs from the table below and get in touch.
Designed to make your composites corrosion resistant, UV protection and aesthetically pleasing, C-Tech provides finishes sustaining the long-term appearance of composite products.
Glossy, unidirectional (spiral wound effect), cloth (woven or twill-weave) effect.
Smooth, clear and glossy cloth or uni finish.
Sanded finish ready for painting or gluing, cloth or uni option.
Textured finish designed as a gluing surface. It can be used inside tubes to create a gluing surface in areas that are hard to sand. This finish also provides a good grip on tubes either cloth or uni.
Sanded and painted, giving a high gloss and the best UV protective coating and a high quality finish. We can offer any colour that is commercially available for spray painting.
We specialise in making square tubes using pre-preg carbon fibre with epoxy resin and have a large range of tooling available. Therefor our Laminated from prepreg carbon fibres and epoxy resin, our square tubes are made for applications requiring high strength and rigidity.
Please note that there is a minimum order value of $400 per export shipment.
Price will depend on laminate thickness and carbon fiber modulus or fiber type required. Price calculators are provided on some pages. If price information is not availableplease enquire about a tube to suit your specifications.
Our invoices can be paid by credit card (Visa/MasterCard - PDF form and complete CC details), by bank transfer, or by internet payment to a local bank (service available in some countries).
We export the majority of our tubes to destinations all around the world. We ship with Fedex, DHL and a variety of other freight companies to deliver customer orders at the best possible price.
Typical lead times for shipments:
Australia and the Pacific: 3-5 days
Rest of world: 7-10 days
We offer excellent lead times and competitive prices on shipments to Australia.
Delivery: C-Tech tube can be delivered world-wide. We use seafreight, airfreight and courier (DHL / FedEx; suitable for lengths under 3 metres).
The Standard terms for delivery of C-Tech Carbon fiber tube internationally are:
F.O.B (Free On Board) i.e. delivery to a freight carrier at Auckland International Airport (TNT, UPS or other Airfreight carrier)
DDU (Delivery, Duties/Sales Tax Unpaid) i.e. standard DHL / FedEx terms
All square or rectangular (RHS) carbon tube dimensions are measured from the inside of the tube (ID). This is because the ID is controlled by the male mandrel it is made on. To determine the approximate outside diameter, add 2x the wall thickness to the ID measurement.
A male mandrel molded square/RHS tube, has the same internal radius as the mandrel its made on. This could very square or a nice big radius, each mandrel is unique. Female molded tubes have a mold designed perfectly to match the required outside radius, so the tube has the perfect outer radius that the application needs.
A male mandrel molded square/RHS tube has very accurate internal size and shape. The inner surface is smooth and glossy, and has great controlled dimensions. Perfect for fitting or gluing end plugs or caps, or mounting brackets and gluing tubes together. However the outside shape is harder to control, its smooth and fair, but might not be perfectly square to engineering tolerances. Talk to us if you need a high degree of accuracy and a smooth inner surface, we have solutions. A female molded square or RHS tube has a excellent outer surface. Smooth, fair and square. Easy to paint and the size is well controlled for sliding into other tubes or apertures. Also for gluing, mounting parts or components, for machining holes or fixing linear guides. The inner surface is generally rough, but we can a achieve a good surface by combining male and female molding. Male molded tubes start with an ID, and the wall thickness controls the OD Female molded tube start with an OD, and the wall thickness creates the ID. Female molds are generally custom made to order.
With composite tubes, stiffness and strength is relevant to the loading scenario, or direction the load/bending is applied. In most cases, weight for weight, square/RHS tubes are axially stiffer than round tubes. Or the same stiffness can be achieved with less weight. Strength is more subjective but we can design the strongest tube to you application and advise on the best sectional shape.
Finish options include gloss, twill-weave, woven, matt, peel-ply, and clear coat finishes (UV resistant). We can offer other finishes based on colours commercial available for spray painting. Ask us about how these finishes can be achieved on the tube you are looking for.