Frequently Asked Questions

Hatches and Portlights

My hatches are about 10 years old. They don't leak, but I can see these funny little shiny lines that seem to be floating in the plastic. Is this ok?

Ten-year-old hatches do not necessarily need to be re-built. The shiny lines however are a source of concern. These lines are referred to as crazing and are a natural occurrence when acrylic is exposed to the harsh marine environment. The crazing lines are actually small cracks in the surface of the Acrylic. As Acrylic is extremely notch sensitive, both the manufacturers of the Acrylic sheet and Select Plastics recommend that you replace your hatch lenses as soon as possible. Until you have time to get these units re-built, do not subject the hatches to any load or sudden impact.

My local marina purchased some Lexan polycarbonate for my hatches. I was told that this polycarbonate material was much stronger and more scratch resistant than Plexi. Can you explain why?

First of all, both Lewmar Marine LTD and Select Plastics do not recommend the use of any type polycarbonate in deck hatches. During extensive testing of several brands of polycarbonate it has been determined that although polycarbonate is stronger than acrylic of the same thickness when installed, It degrades and yellows at such a rapid rate, that its useful service life could be half that of acrylic. Due to its high impact strength, polycarbonate is very ductal. This flexibility makes the material extremely difficult to seal in a hatch that was designed to accommodate the stiffer acrylic sheet. Scratching or abrasion is a significant problem with polycarbonate. The material in its standard grade has a much softer surface than acrylic. The slightest rub will cause a visible scratch that cannot be removed. Several of the major manufacturers of polycarbonate have introduced scratch resistant-ultra violet stable material to address these issues. It has been our experience that even with these costly and hard to find upgrades the special surface coatings tend to de-laminate due to the exposure to the elements. If you can't count on it to seal why use it? Polycarbonate also cost more than Acrylic of the same thickness. Add in the up-charge for the scratch resistant-ultra violet material and the material cost could easily be double that of Acrylic. Don't get us wrong; polycarbonate is definitely necessary and extremely useful. The U.S. Navy and United States Coast Guard even require it in certain applications on their vessels. Select Plastics just wants to provide you with the correct information so that you can make an informed decision regarding your particular vessel.

Can I buy the Plexiglas and adhesive from you, and seal the hatch myself?

We are first and foremost a precision marine plastics fabricator. We would be happy to supply you with any fabricated part you require. All you would have to do is send us with a sketch or pattern of the part, we would then supply you a quote explaining the type of material we would use and the total cost for the job. You would approve the quote and the part would be made. We would not be able to supply you with the adhesive or any sealing recommendations. Select Plastics feels that the process and procedures involved in the correct sealing of deck hatches is so specialized that the average person or marine facility would not have access to the equipment or materials necessary to do a SAFE job.