By Mike Kent - Interlux Sales Representative
A freshly painted bilge is much easier to wipe down and keep clean; as well a clean bilge reduces odors that may result from residue that is left unchecked. It is also much easier to find things such as small fasteners or parts that may have been dropped while working on your engine or other equipment. Bilgekote acts as a barrier by sealing the surface, helping inhibit the migration of water, oil and other chemicals into the substrate.
Before we start lets talk about safety. Bilges are normally enclosed areas that do not allow much if any air movement or ventilation. Observe caution when working with paints, solvents and cleaners because you can experience a build up of fumes. You should wear an approved and well-maintained respirator, solvent resistant gloves, protective eyewear and protective clothing.
Due to the nature of bilges it is extremely important to clean the surface to be painted before proceeding with other prep work such as sanding. Any contamination could easily cause the coating to not adhere or dry properly. It's extremely important to wipe down or even scrub the bilge with Interlux 202 Fiberglass Solvent Wash or YMA601 Fiberglass Surface Prep before sanding the surface. Sanding the substrate before cleaning it properly will embed any contaminants into the sanding profile (grooves) making it much more difficult to clean later.
Since the bilge was bare fiberglass and is in good condition begin by scrubbing the fiberglass with soap and water and a stiff brush. Then rinse with fresh water and allow to dry over night. The next day degrease the surface by wiping with a damp rag of Fiberglass Solvent Wash 202 then wipe dry with a second rag. This is called the "two rag method". At this point sand with 180 grit sandpaper. Then use the "Two Rag" method again with Fiberglass Solvent Wash 202 to remove all the sanding residue left after sanding.
Can't sand the bilge?
Some boats have a rough weave in the bilge that cannot be sanded but it will still need to be cleaned and prepped well before painting. If this is the case in your boat you can use YMA601 Fiberglass Surface Prep in stead of Fiberglass Solvent Wash 202.
Apply YMA601 Fiberglass Surface Prep to the surface with a 3M maroon Scotch-Brite® pad, and then scrub well. Flush well with freshwater or wipe off with a clean, wet cloths ensuring that no traces of Fiberglass Surface Prep remain. Before application of Bilgekote or primer it is very important that all contamination has been removed. To be certain the contamination has been removed, run water over the surface. If the water beads up or separates, wipe again with YMA601 Fiberglass Surface Prep. Once the surface is cleaned apply Bilgekote.
Note: Putting down 1-2 coats of Interprotect 2000E White will provide extra protection from gelcoat blistering.
Now it is time to paint. I applied two coats by brush over a period of two days, one coat each day. In-between each coat you will need to sand with 220 to 320 grit sandpaper. Don't forget to remove the sanding residue by again using the "Two Rag" method. The only difference this time is use a rag dampened with Interlux Brushing Liquid 333 or Interlux Special Thinner 216. Use Fiberglass Solvent Wash 202 on fiberglass surfaces only as it will damage painted surfaces.
Some hints to make this project easier are:
- If you are working in hot temperatures you can thin the Bilgekote with Interlux Brushing Liquid 333 to improve brushing characteristics but thin no more than 10%
- It is best to paint on warm, dry mornings
- Beware of working in cold weather because it can retard the drying
- Beware of working in high humidity because it can spoil or spot the gloss
- Bilgekote can be brushed or rolled
- Ensure proper ventilation in tight areas
Original article from Interlux