Yet another project on the ever long list of to do’s for Whistlin’ Riggin’, our 36’ Union Polaris can now be crossed off:


This project took us the better part of three days, between the extensive prep work required to rid the bilge area of dust from other boat projects and the multiple coats required to paint the bilge properly. The paint we used was TotalBoat TotalBilge Epoxy Bilge Paint from Jamestown Distributors.

Cleaning the bilge before applying bilge paint

Before even thinking about opening a can of paint, it is very important to make sure the area is properly prepared.

Clear the area of any loose debris using a shop vac.

It also better to have a corded vacuum that is also wet/dry vac, as battery operated ones always die before the job is done and suction can be weak. Assuming you’ll primarily use it on your boat, you will always find something that is wet or damp that could wreak havoc on a standard shop vac. Our always reliable 2.5 gal Craftsman shop vac is one of our favorite tools for the boat since it is compact (as far as shop vacs go) and can reach into the hard-to-get areas of our boat, including the bilge! When using your shop vac, make sure to use a bristle/brush adapter as to not scratch up any wood veneers or delicate surfaces. A hard plastic adapter might level permanent scratches.

This is the time to tackle any oil or other tough-to-remove residues in your bilge.

This will vary drastically between boats, so it’s best to first identify what exactly the kind of oil/residue/gunk is that you’re facing, and then seek out the appropriate product to remove it. As much as you may not want to hear it, sometimes the best ‘product’ to remove it is good ol’ elbow grease and a little hard work. Personally, we only use biodegradable cleaners and oil removers. Some of the best degreaser products we’ve come across are Storm Force, Z-cleaner, or Simple Green. For larger oil clean up projects we cup the oil out by hand and wipe up as much as we can with paper towels before using any other products.

Wipe down any dust or other small particles using a wet rag.

For the first round of wiping down the bilge, it’s best to just use a good ol’ fashioned bucket of water. The reason we like to use water first, is because water is your safest bet on all surfaces you may come into contact with. We also use denatured alcohol, mineral spirits, and acetone with the above listed degreasers, but you have to be mindful which solvents you use on each substrate. The last thing you want to do is ruin a finish using the wrong solvent.

The last pass through on the bilge should be a wipe down of the surface with denatured alcohol.

Since you’ve already wiped down the bilge area with a wet rag, this last pass through is to ensure that all those pesky dust particles are going to be gone for good. Use a clean rag for this process and don’t take shortcuts by trying to reuse the wet rag you used in the previous step. Repeat this step as often as necessary until your rag comes up clean. This will ensure the surface is as clean as it can possibly be in preparation to paint the bilge.

One extra for the perfectionists: a tack cloth.

Finally, we’ll use a tack cloth areas that we think may have any dust particles still stuck in there despite our best efforts. This step really just depends however far you want to go with the cleaning stage and just how flawless you want the outcome to be. We also often do this with wood we plan to paint or varnish or sometimes even FRP (fiberglass),

Choosing a bilge paint color

There are a few different colors of bilge paint available on the market and after thinking through a handful of practicalities, we ended up choosing white. We chose this so if anything reside such as water leaks or oil leaks occur they can be traced appropriately with color dyes that will show on white surface. Plus, white brightens up the interior of the boat in general and even though our floorboards will be covering the space, it just feels brighter knowing it’s there. More practically though, if we ever need to poke a flashlight into a tight corner of the bilge, the light will reflect much better into the space making life much easier recovering the missing fastener you dropped working on a future project.

Materials to paint the bilge

Brushes and rollers are the name of the game, and getting the right one can potentially make all the difference. A lesson learned during our first coat was to get foam rollers that are solvent resistant; don’t be cheap here! The first set of rollers we used ended up saturated by the paint and began falling apart. When it comes to brushes, we did not worry about getting the higher-end badger brushes we would normally for varnishing, but settled for the lowest price point we could find that wouldn’t fall out the moment we pulled on it. After all, this is just bilge paint, and chances are your bilge is not silky smooth so any bristle brush traces won’t be a problem. Our materials list for this part of the project included:

  • 6 paint rollers (4 inch & 9 inch) – using an expoy-based paint made it nearly impossible to clean the rollers between coats, so we opted to just dispose of the used ones.
  • 6 paint brushes (assorted widths based on preferences) – since we were using cheap brushes, we did not bother to clean them after use and used 2 during each coat.
  • 1 paint stirrer for drill – this does the heavy duty stirring
  • 3 disposable paint stirrers – we used one clean paint stirrer to stir the paint prior to each coat
  • 2 large paint trays – using our 4 inch and 9 inch rollers, we opted to just get the 9 inch pan and use it for both. We also bought several plastic inserts so we could just use a fresh new one when starting a new coat and didn’t risk rolling it in dry paint.
  • 2 roller handles (4 inch & 9 inch)
  • 5-10 clean cups
  • Denatured alcohol & box of rags – to have on hand for any stray drops of paint. You can also use old shirts but it’s important to be sure they are clean before using them.
  • Blue painters tape – used to mark off the edges of the tight spaces we didn’t want the paint to get on (i.e. bottom of our cabinets)

Deciding on how many paint coats and when to paint them

When it comes to decisions like this, it’s best to go with the manufacturers instructions. In our case, we used three total coats of the TotalBoat TotalBilge Epoxy Bilge Paint. For our 36′ boat, we went through 2 gallons to paint the bilge. Depending on the paint you go with, this may vary based on how thick the paint is and the area of the bilge you’re planning to cover. Following the product instructions with dry time between coats is going to be your best bet, however there may be ways to save some time by… modifying… the method. For example, the TotalBoat TotalBilge Epoxy Bilge Paint instructs to sand between each coat of paint to rough up the surface and then clean away any loose dust from that process and then paint the next coat. While this would have been the proper way to complete the project, we were working with a three-day time constraint so we painted the second and third coat while the preexisting coat was still a bit tacky. This allowed the new coat to still have something to lay onto that it would stick well to, while also saving us time. By all observations so far, this hasn’t been a shortcut we regret.

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Get creative about where to stand

This is obviously going to be very project specific when you paint the bilge, but slide through the photos above to get an idea of how we solved this problem. We had struts we were able to place planks across to stand on for the majority of the time. Eventually, we backed ourselves towards the companion way and at the very end, found ourselves precariously perched on the inspection ports of our diesel tank to get the tops of the final struts.

It’s not a glamorous project, but it sure is a satisfying one to finish!

Did we mention this took us three full days to complete? Yup. With help from two others for part of the time. Painting the bilge is not a short project, and since almost half of the project time was spent on prep work… definitely not glamorous. Yet the difference it makes sure is easy on the eyes!

If you have any questions about our process, materials, or anything in between, please don’t hesitate to contact us.

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