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Cleaning the brush: A Chemical Engineer’s perspective by Bob of Eolian

Good varnishing brushes are definitely not cheap! The quickest way to ruin one is to let varnish dry in the brush – not something any of us wants to do.

But cleaning a brush is not an easy task. You may think that after triple-rinsing it in fresh paint thinner, the brush is clean. But put it away for a couple of days, and when you go to use it next, the bristles are  disappointingly stiff.

As a Chemical Engineer, I learned several things that have made brush cleaning a lot easier.  (What?  Practical knowledge?  Who knew?):

Use a counter-current wash system. This keeps the clean end of the system separate from the contaminated end. In a real chemical plant (for example, an alumina refinery) there would be as many as 10 stages or more. Here we will make it simple – we’ll use only two.  Do it like this: Save an empty paint thinner container. When you rinse out your brush, dump the now-contaminated solvent into this container. Soon you will have lots in there. As soon as you have enough, this is now your stage 1 rinse.  Squeeze out all the varnish you can from the brush, and then clean it thoroughly in the stage 1 rinse solution. Squeeze out all the stage 1 rinse, and wipe the brush on a rag, trying to absorb as much of the stage 1 rinse as possible. Dump the stage 1 rinse back into the stage 1 container. Next, rinse the brush in 3 small changes of clean solvent. As above, drain all the now contaminated fresh solvent into the stage 1 rinse container, wiping the brush nearly dry between rinses.

This works because even tho the stage 1 rinse is not pure solvent, it is not very far from it, […]

Windsong: Cleaning the Bottom

Since hauling Windsong out of the water I have been focusing most of my energy on her hull below the waterline. My goal was to get the hull to the point where it could dry out for the rest of the time on land. This would mean removing paint and the gel coat (if necessary) and then leave the hull alone while I worked on the rest of the boat. Fiberglass boats do in fact absorb water through osmosis (what creates blisters). The hull needs to be completely dry before I apply the planned epoxy barrier coat (protects against water absorption) and then paint.

I had researched many different ways to remove paint from the bottom. The most common choices are to sandblast, grind, use a chemical peeler, or just old fashioned muscle and scraper. I opted for the simple method of scraping with a cheap paint scraper from Home Depot. The bottom paint was loose enough where the majority of it came off with the scraper. I would scrape a section of hull then go back and sand away the remaining paint down to the gel coat. I started at the bow on the starboard side and worked my way back. Here is the hull after the first weeks work: Removing the old paint to the gel coat revealed quite a few small spots where fairing compound was used in some sort of repair. It also revealed the blisters I feared would be present. The worst case scenario in my mind were thousands of small blisters all over the hull. But what I discovered were isolated, larger blisters averaging about 3-4″ in diameter (some larger some smaller). When I found a big blister I would drill into it with a countersink bit to release the fluid inside. The fluid […]

Windsong: The Haulout

he Monday after we sailed Windsong into St. Augustine we finally hauled her out to begin the massive rebuild. I had been anticipating this moment since I bought the boat about a year ago. I had never seen the hull below the waterline but knew a little bit of what to expect. I dove down to check the bottom once, but it was too murky to see anything. I could feel blisters however near the waterline so I figured I would have a few of them. Windsong was kept in warm Florida fresh water for a long time without a bottom job, ripe conditions for blister problems. I feared that she may have a case of full blown pox – a condition of thousands of tiny gel coat blisters covering the entire hull. This was the worst case scenario and I wanted to be prepared for it. I didn’t expect any other major problems with the hull, though I anticipated some damage on the keel from when we ran hard aground. During the past year I have been studying all that I will need to do to the hull depending on its condition.

It was a gross morning with a ton of rain. We hauled her out in the downpour and I got a first look at the bottom Proud owner 🙂 After the haul they gave her a good pressure wash. There wasn’t much growth on the bottom, just some slime. She had only been in salt water for about two months and the water was pretty cold the whole time, so barnacles didn’t get time to grow. The pressure wash was taking off chunks of old paint that had begun to deteriorate over time. It turns out, the gel coat blisters I thought I felt were actually just […]

Website and Forum Updates

There were some fairly major updates to the website and forum software that I ran today. I’m not sure that you will notice much difference in actual usage, however there are probably a fair number of new features or tweaks as well as all the security updates etc…. If you do run across something that is not displaying correctly then empty your browser cache and try it again. At that point if there is anything that is acting weirdly or not working let me know about it.

Your friendly webmaster

Scott Carle

PS.. if anyone wants a new language pack other than english for the forum I would be happy to install it if you want. It will not affect the language of the posts themselves but it will affect all the controls of the forum that you use.

Bilge pump

This is a blurb I wrote a few months ago and had saved as a draft. I forgot that I hadn’t published it. So a bit late but here it is.

The reason we went up to the boat for the last few days was to clean her up a bit and get the bilge pump working again. A few months ago the bilge pump had come on continuously and for some reason couldn’t be turned off. I’m not sure that Angela even knew it was the bilge pump as it is a really nice diaphragm unit that sits up in the back of the engine compartment and doesn’t really look like a what you would think a standard bilge pump would. It ran for a  day or two before she found out where the noise was coming from. It’s pretty quiet when running dry. Finally she just cut the power line to it to get it to turn off. I think what happened is that the automatic switch went bad or the control panel for it went bad and left it running.

Me in the engine compartment reconnecting the power to the bilge pump.

The new panel I ordered to replace the old one.

The Sea-Dog 422035-1 provides an audible and visual means of warning that water level in your bilge is beyond your bilge pump float switch level and it has a control switch to select between automatic and manual mode of the bilge pump.

I am planning on getting two

JOHNSON ULTIMA AUTOMATIC FLOAT SWITCH Patented Mirus field effect detector cells producing micro-electrical fields that detect disruptions caused by water and fluids. Detector cells are totally sealed and are never in contact with water, will not corrode and are not affected by oil or foreign debris. […]