Canon EOS DSLR Main Scroll Wheel Repair

Canon EOS DSLR Main Scroll Wheel Repair

Here’s a simple and quick fix for Canon EOS DSLR owners. I’ve owned various Canon DSLR’s over the years and about 5 years ago acquired a mint EOD 50D. It’s a nice camera with a very low shutter count. Obviously it’s been superseded over the years but one problem with this style of DSLR is the main dial wheel as shown below.

The wheel is actually what looks to be a ‘knurled’ style piece of circular rubber which sits onto a grooved plastic wheel. Many Canon DSLR’s use this style of wheel/dial. What does quite frequently happen, is that grease and dirt becomes embedded on the underside of the rubber wheel and gets trapped within the groove of the plastic. The result is that the top rubber piece just spins around the lower plastic wheel meaning the wheel now fails to change any of settings making the camera pretty well useless, especially if you use it on manual.

I originally did some online searching and saw a ‘Fix’ that one brave owner tried by putting a small slither of superglue between the rubber wheel and plastic. It’s a pretty precarious solution and one small slip could see the whole wheel stuck with too much super glue. Here’s a much cleaner and simpler fix and requires no disassembly of your camera.

The outer wheel is a ‘knurled’ style piece of circular rubber which sits over a grooved plastic under wheel

Given this, I tried my own remedy. We have a bottle of full strength 99.9% ‘Isopropyl Rubbing Alcohol’ in the workshop. If you don’t have any, it’s only a few pounds on eBay or Amazon. I gently prized the rubber wheel upwards using a paper clip just so it lifted off the surface of the plastic wheel. Then using a small cotton-wool bud, applied some of the rubbing alcohol between both wheels. I then moved the rubber wheel slightly and repeated. I continued repeating around the whole circumference of the wheel. Soak the bud and be generous with the liquid as any excess alcohol will evaporate fairly quickly afterwards.

What you will find is that even after turning the wheel once or twice, it will begin to grip the lower wheel and tightly. The great thing about rubbing alcohol is that it’s non conductive and makes for good use on electrical circuits. Having too much is therefore not a problem. PCB’s are frequently cleaned using this liquid so it’s electrically safe to work with.

Use max strength Isopropyl Alcohol [99.9%] – best not to use stock of a weaker concentration

I then moved the wheel right and left. A great result – with no more slipping. The alcohol had dissolved the dirt and grease between the wheels and the rubber once again gripped the plastic wheel extremely well.

Since applying this simple fix 10 months ago, the camera continues to function as expected with no more slipping wheel. Of course the great thing about this is that it means the camera does not have to be disassembled and you don’t need any dreaded superglue!