Once you have created your carbon fibre part(s), either by way of infusion or wet lay-up, you will most likely need to get your parts ‘showroom ready’ by trimming, cutting or filing them to achieve the perfect result.
In this article, we take you through the necessary steps required to complete this procedure as well as giving an insight into the tools that are required to do it safely.
GETTING STARTED
Safety First
First, you will need to decide on the level of respiratory protection you will require. This will depend on a number of factors:
- The amount of cutting and sanding you are doing will affect the volume of particles in the air
- The existing extraction capabilities of your working environment. An environment with strong extraction facilities already in place may well reduce the severity of personal protection required
Once again, depending on the nature of the task being undertaken you should also consider your clothing protection, as not only can recently demoulded parts be razor-sharp at the edges, but carbon fibre dust can cause irritation to the eyes, hands and forearms. We would therefore recommend that you wear suitable protective eyewear, gloves and overalls to avoid any unnecessary risk.
For hand protection, we recommend a pair of Kevlar Gloves, lightweight and comfortable so allow you plenty of movement to work on your product but provide a high level of protection against sharp edges.
If you are planning on carrying out lots of sanding then we suggest full-body protection such as the BAXT C3 breathable ‘Prepper’ disposable coverall, designed for maximum dust protection.
For a brief overview of respiratory protection read our article here. Or to understand the full safety standard requirements around working with carbon fibre read our article here.
The right tools for the job
Next, you will need to decide just what it is you want to do, as the amount and shape of material you want to remove may well dictate the tool(s) you use. For example, for cutting off large sections of material in straight lines the best tool for the job would be an angle grinder, whereas if you have complex shapes you need to trim you may opt for a Jigsaw or a Dremel.
The main thing to remember is that the finer the abrasive, the better the end result will be. For example, a GRP cutting blade for a jigsaw will have large, jagged teeth and will chip and fracture its way through the resin as you cut, leaving you with a very rough and messy edge to clean up. In direct contrast, an abrasive blade such as one coated in Tungsten Carbide will give a much cleaner cut, greatly reducing the amount of finishing work you will need to undertake.
CUTTING SANDING & POLISHING CARBON FIBRE
Cutting:
To reduce the number of chips and splinters within the carbon fibre laminate it is widely recommended to use a blade with as many teeth as possible, or preferably a tool with an abrasive edge. E.g. Metal cutting discs or Tungsten Carbide hacksaw / jigsaw blades.
Always ensure you cut slightly less off your material than you actually need to remove, this will allow you to sand back the excess material, giving yourself a nicer edge finish to the final piece.
In terms of the actual cutting tools available for carbon fibre, there is, at the time of writing, no specialist cutting tool available. In fact, you are free to use any number of tools including, Hacksaw, Dremel, Angle Grinder or Jigsaw…..the trick, as we have stated above, is to use either a blade with very fine teeth or, ideally an abrasive material in place of teeth.
Whatever you use, we recommend utilising a cutting surface such as a high-density foam to allow you to cut cleanly and evenly through your workpiece.
Sanding:
To remove the last few millimetres of carbon fibre, tidying up any chipping of your edges we recommend a simple sanding block used with a mixture of coarse and fine abrasive papers to allow you to get the very best finish.
As ever, take care to wear the correct PPE equipment, as sanding can produce a large amount of very fine dust particles that can easily cause irritation.
Polishing:
If you wish to polish your cut edges you can do so with a very fine 180 or 400 fine-grit sandpaper wrapped around your sanding block, which should give a perfect edge finish for your trimmed parts.
Given your part is new, and fresh out of the mould it is doubtful you will need to polish any more of the part other than the cut edges.
 For more information about our wide range of products serving the composite sector please call us direct on 02380 251100 or visit our website.
