Styli Ball Cleaning: Ensuring Consistency With Your CMM Inspection Results

Achieving consistent measurement and inspection results time and again is a must for many of our clients who invest in a CMM machine. Several factors can affect inspection accuracy and one of the easiest ones to rectify is the styli ball.

Often, simply due to regular use, the styli ball on a CMM will suffer from build up of dirt, contaminants and debris (examples in the images below).

If this is not cleaned away regularly and thoroughly then inspection accuracy will drop, resulting in inconsistent measurement results and potentially failing to meet quality standards. As well as this, adhesive and abrasive wear can affect a styli’s performance, these will both result in permanent changes to the ball’s composition and can’t be rectified. In this instance, a replacement styli is required.

To prevent contaminant build up or to catch adhesive and abrasive wear at the soonest, our team of metrology experts recommend that you clean and inspect your CMM styli ball frequently.

Let’s take a closer look at how to properly inspect your styli ball for adhesive and abrasive wear and how to thoroughly clean it to remove dirt and debris…

Inspecting your Styli Ball

Inspecting your styli ball should be done using a microscope and strong light source of at least 1000 lumen. Below are the microscope magnification recommendations for specific ball diameters…

• < 1 mm – 40x to 80x magnification
• 2 mm – 8 mm – 10x to 40x magnification

Cleaning your Styli Ball

For styli ball cleaning, you’ll need to use canned air, IPA and small to large lint free buds depending on the ball diameter under a microscope. Always take care when cleaning styli and never use an abrasive or corrosive cleaner.

Below are recommendations of what should be used for specific diameters…

• < 1 mm – use only canned air under a microscope
• 1 mm – 3 mm – use small lint-free buds
• > 3 mm – use large lint-free buds
• Datum balls – use a soft lint-free cloth

The method of cleaning styli balls over 1 mm should always be the same. Simply follow the steps below…

1. Remove the styli from the probe
2. Soak the lint-free bud (small or large, depending on ball size) in IPA.
3. Wipe off any excess IPA from the pump pot.
4. Clean the ball by sweeping around its equator with the lint-free bud in one direction and follow up by wiping the top surface. This should be done under a microscope and with minimal pressure.
5. Use canned air to dry the styli before reattaching to the prove

Datum balls are slightly different and can simply be cleaned by sweeping around the ball with a soft lint-free cloth (IPA can be used in conjunction with this). Note that the ball should be completely dry and the IPA evaporated before using again.

Need further advice?

Still not sure about styli ball cleaning and require further advice from our metrology experts? Drop us a call 0115 939 2228, or fill in your details on our contact form and we’ll respond as soon as possible!

Alternatively, if you require a new CMM styli then take a closer look at our catalogue here.