Repairing an Acrylic Dome Port

During a year of pretty heavy use my dome port has received its fair share of small scratches. Luckily they are not really a problem underwater as even fairly deep damage fills up with water and doesn’t show up on photos. However, lately the damage has started to show up in split shots and even some underwater shots. Particularly the latest scratches acquired during the Phillip Island trip were quite bad and as they are showing up even on underwater photos something had to be done.

Acrylic dome ports are expensive pieces of equipment so replacing them every year is not really an option. Luckily even fairly nasty damage can be repaired relatively easily with the right tools. Hobby kits for polishing and repairing acrylic items are readily available and lot cheaper than replacing the whole port or using commercial repair services. I ordered one online from an Australian reseller Sandpaperman on Ebay and got to work.

The kit I used had 9 different grades of sandpaper. The kits are available in two different types, either more traditional sand paper type or soft touch pads that are more suitable for small jobs. After some online research I went with the touch pads, but I don’t think it makes a huge difference in the end.

The sandpapers start from fairly coarse and progress down to very fine indeed. The coarse ones are used to remove the original damage and then the dome is smoothed and polished at stages using finer and finer pads. To finish the job I used an abrasive liquid, however at this point there was not much difference between the last application of sandpaper and the liquid polish.

While the few initial steps were little bit scary (the dome gets quite opaque) the end results were quite good. Pretty much all the damage showing up in photos is gone and that’s what counts. However, I should have taken little more care with the edges of the dome. The results from different sandpaper grades were bit uneven and there are some visible scratches from the process itself. Luckily they are far enough on the sides so they don’t actually show up on the photos but it would still be nice to get rid of them at some point.

Luckily the pads are reusable, so improving the smoothness is simply a question of time and effort. The actual operation took me little over an hour, which is not too bad considering it included some extra time taking the photos.

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