Fixing Scratches on Your Fiberglass Boat

Something to do in the off-season when you're not going to be 
out on the water for a bit.

Repairing scratches on a fiberglass boat is a relatively simple process, albeit a bit on the messy side. You will basically be refilling the gouged out area with new fiberglass. Shallow scratches are easily done. With deep scratches you’ll have a more complicated task ahead of you. Here’s how to do both.

Materials:

• Epoxy fiberglass resin and hardener
• Respirator
• 4-6 oz. E-glass Fiberglass fabric (4 by 8 inch square)
• Scissors
• Disposable mixing cup and stirring stick
• Sharp knife or chisel
• Sandpaper and sander
• Acetone
• Styrene (small bottle)
• Plastic film
• Disposable brushes
• Plastic flexible spreading tool
• Latex or rubber gloves
• Duct tape
• Power buffer and fine grade buffing compound
• 
  

For Shallow Scratches:

Step 1
Clean the hull around the scratch with soap and water and then wipe with a rag wet with acetone. Wear gloves while handling acetone and all fiberglassing liquids.

Step 2
Drag the point of a knife or corner of a chisel down the scratch to widen it slightly to accept the repair more readily. Lightly hand sand to remove any bits of fiberglass sticking up along the edges of the scratch. When the scratch edges are level with the rest of the hull, you’re ready to go.

Step 3
Mix up a small amount of epoxy based fiberglass resin. For most scratches you’ll use less than a quarter cup of resin.

Step 4
Tease fibers loose from the edges of a piece of lightweight fiberglass fabric with your gloved fingers or a small sharp knife blade. When you have a little pile of them, place the fibers next to the scratch. Dip the fibers into the resin cup and lay them in the scratch. Stagger the threads so their ends overlap. As the fibers fill up the crack, brush lightly over the top with the fiberglass resin. Use the spreader tool to press the resin flat across the top of the crack and smooth out any air bubbles or bumps.

Step 5
Allow the resin to set and cure overnight. Lightly sand with fine sandpaper, and then fine steel wool. Polish and buff with buffing compound to a shine that matches the rest of the boat. For very light scratches, polishing and buffing over the scratch may be all you need to do and you can skip the fiberglass mess.

For Deep Scratches:

Step 1
Use a sharp pointed knife or corner of a chisel or screwdriver to clean out and widen the scratch so the repair material will set better. Clean the area around the scratch and wipe with acetone dampened rag.

Step 2
Lightly sand the edges of the crack to remove any burrs sticking up above the rest of the hull.

Step 3
Mix up a small batch of gelcoat paste. You will have to match the color of the boat. Gelcoat paste repair kits come with a selection of pigments to mix with the paste to match the original color of the boat. This is the hardest part. If you can find a matching color swatch at your local paint store, they can tell you what pigments in what proportions will match your color. You’ll have to do a little math and you will very likely waste several batches of gelcoat paste. Get it as close as you can. Buffing may help disguise any minor color variation. Color the paste BEFORE you add the catalyst. Add the pigments one drop at a time to an ounce of paste in the proper proportions. When the paste looks close to matching, put a drop on the boat hull and check to see how close it is. When it’s right, write down the number of drops of each pigment per ounce for mixing later batches of gelcoat paste. Add the catalyst and stir. Follow the directions that result in hardening in 30 minutes to 2 hours.

Step 4
Wipe the scratch with styrene before applying the gelcoat paste. This reactivates the old gelcoat and helps improve the bond between the old fiberglass and the repair.

Step 5
Spread the paste into the scratch with your spreader. The paste will bulge up a little after the spreader goes over it. Don’t let it bulge too much or you’ll have a lot of sanding to do. Wipe off any excess paste. Cover the gelcoat with a sheet of plastic film and tape it down. Gelcoat won’t fully cure in the air. Let the repair cure for 24 hours. Sand with fine sandpaper, then with very fine wet sandpaper and finally with fine steel wool. Buff with rubbing compound to a high gloss and then give the hull a coat of wax.

Did You Know Your Uber Driver Can Get You Shadow-Banned from Uber?

LITTLE KNOWN FACT ABOUT UBER: A recent discussion on Right Angle talked about people's reluctance to give a bad rating to our Uber drivers. Yes, we get to rate the drivers and that can be an attractive way for jerks to harm their drivers.  We decent folks are therefore reluctant to trash drivers with one and two star reviews for fear of costing them their jobs. But Uber drivers are not defenseless. Did you know that UBER DRIVERS ALSO RATE THEIR PASSENGERS?

Several low ratings by passengers can get an Uber Driver removed from the list. So we have good reason to be careful not to overreact when we rate a driver. Who wants to get a guy fired (anyone who is not an entitled, drunk on power, #$$#()|& that is)? But the little-known fact is, that Uber drivers rate their passengers and several low ratings can leave you stranded because drivers won't pick up passengers with a low rating.

I got a message from Uber several months ago that a driver had given me a low rating. Uber then proceeded to give me a lecture about wearing a mask in their cars. I investigated further and found that the driver had burned me because I got into the car from outside and forgot to put on my mask. Instead of reminding me to do so, which would have got him an apology and my instant compliance with Uber's mask mandate, he remained in a sullen silence the whole trip and then low rated me afterward.

Needless to say I reciprocated vis-a-vis giving him a low rating and expressing my opinion to his bosses. Instead of giving me a polite reminder about the mask and protected me from the vile streams of CoVid virus spewing from my nostrils as I breathed, he clearly jumped to the conclusion that my noncompliance was due to me being a Republican White Supremacist conspiracy theorist who might commit violence against him in his car in the midst of a deadly pandemic. These people make me so tired!

To their credit, the Uber system does allow you to protest the low rating by contacting their customer service and giving your side of the incident. It also allows drivers to warn other drivers that this passenger is bad news. That makes for a more friendly environment for both drivers and passengers. In all of the hundreds of rides I've taken with Uber I've only had that one problem and the trouble erupted after the ride was over and I was safely home.

Uber has a good system, but knowing the driver gets a vote on how well you behave as a passenger should probably be more widely known among riders. It might result in a lot more self-restraint among their riders. I've driven a taxi so I know how much I appreciated the polite people I carried in my cab. Met some of the nicest drunks that way. They used to hand me their wallets and say, "Take what you need!" at the end of the trip. I never cheated them, not gave myself even a tip as they were too impaired to make that sort of decision. And I couldn't even rate my riders, nor could they rate me. This was Ft. Worth, Texas after all and people tend to gravitate toward nice by and large in those parts.

The closest any of us ever got to being able to rate our passengers was by throwing them out of our cab. One driver (not me) picked up a drunk at Felix Bar in downtown Ft. Worth late one night. The driver got pulled off the cab stand at the Hyatt where most of the riders are headed for the airport or are great tippers so he wasn't in a mood to put up with much from a $3 fare. The drunk he picked up immediately got surly because the barkeeper had cut him off and he somehow got it into his head that the barkeep was in cahoots with the cab driver. He began threatening the driver and shouting threats at him from the back seat. The guy was driving one of those old yellow Checker cabs with the flat back floorboard that made for easy egress. So anyway, the guy was sitting on the right side of the back seat, leaning against the door as he berated the driver. So when they reached 7th Street, my fellow driver made a sharp left hand turn onto 7th and mid-turn, reached back and flipped open the back door and let centrifugal force do the rest.

His increasingly violent passenger, rolled limply out the door and onto 7th Street, one of Ft. Worth's busiest thoroughfares. The cab disappeared into the night leaving the drunk in the middle of the street in a puddle of his own vomit. Fortunately, at that time of night, the street was pretty empty so no one ran over him. 

The driver, in effect, rated him 0, GONE, and canceled.The drunk meanwhile couldn't identify the driver or even remember where he was picked up and why. Driving a cab was hazardous enough without having someone sitting behind you threatening violence. We often had to come up with some creative solutions to avoid problems, but we essentially had little or no choice as to who we picked up.

I personally think Uber's system is much better. It is a close to insuring everyone behaves themselves and provides both members of the ride-share transaction with means to defend themselves and as Robert A. Heinlein once said, "An armed society is a polite society."

© 2023 by Tom King

Building the Homemade Cajón (Peruvian Drum)

You may have never heard of a folk instrument called a cajón. You may have seen one and not realized it was a drum. We smuggled one into our special music one Sabbath. Our church at the time had an older congregation who looked askance at percussion instruments in the sanctuary. We'd have never got a drum set approved by the church board. Turns out one of our kids sat on a a cajón playing soft percussion to fill out the guitars, bass and violin for several weeks before someone twigged to the fact that Bobby wasn't just sitting on a box, but had been playing it all along. People heard something that sounded like percussion, but couldn't figure out where it was coming from. The cajón helped desensitize our older more traditional members to the presence of a percussion instruments in church. Later he was able to play it with brushes and drumsticks (gently of course).

A cajón is shaped like a box, about the size to offer the drummer a comfortable seat. It can have a sound hole in it, slits, or no hole at all. Some mike them up with piezo-electric or other types of instrument pickups. You slap the front or rear faces, even the sides, with the hands or fingers mostly, but some drummers use brushes, mallets, or drumsticks. Cajones are widely used in South America and Africa, in Latin American music, Afro-Peruvian music as well as Mexican folk music, flamenco and  the Cuban cajón de rumba and the Mexican cajón de tapeo. 

The cajón comes originally from Peru. The cajón takes three main forms: the bass box drum, the middle drum, and the solo drum. It is believed that the bass box drum was originally developed from wood salvaged from shipping crates. The crates were large enough for the percussionist to sit on top of it. The middle drum is thought to have come from a smaller shipping box used to ship church candles. The middle drum is played with spoons rather than palms and fingers. The first solo drum may have originated from a salvaged desk drawer. Modern cajónes may be made of metal or plastic, which is up to you, but it feels blasphemous to use anything but wood.

A cajón tends to be a very personal instrument. Drummers often build their own boxes, alter the design and may use several woods to get a different tone to each face. One guy I know of builds the front from Masonite and uses three different types of wood for three different tones - one for each of the other sides. This allows him to vary the sound of the beats as though you had multiple drums.

Check lumber dealers in your area that deal in hardwoods and specialty woods. Cruise the internet for specialty wood dealers in your area. But don't necessarily depend on store-bought wood for your cajón. Old furniture can also provide you with some unique solid wood pieces in maple, mahogany, pine, cherry, and lots of other woods. You want to checked out the wood's tonal qualities in person as well as the looks of the wood. The body of the cajón is usually open on the bottom and sits flat on the floor, but if you want to skip cutting a hole in your lovely wooden drum faces, you can add short legs to lift the box off the floor to let the sound out from beneath.

One way to determine the wood tone and timbre of each wooden side is to build a plywood box the size of a cajon and leave one side off. Then simply lay the wood you are considering using and beat on it so you can hear the tone. Try different types of wood until you find a wood type that gives you the tone you like - thicker sides and thin sides. Some specialty wood dealers will let you bring your box to the store and experiment with pieces of wood they have for sale. Thinner pieces of wood will give you louder sounds when using hands, fingers or brushes. Thicker pieces may be more of a tone you want if you are using drumsticks or mallets

If it were me I'd try a variety of woods and a variety of thicknesses. I like wood salvaged from old furniture that's being trashed. You might start with maple, rock maple, cedar or spruce at first. Then give some more exotic woods a try. Make your cajón completely unique. A luthier friend once found some old growth Black Forest lumber that had been sitting in a shed in Germany for a hundred years and made violins with it using a Stradivarius pattern. They sounded wonderful. 

Also, don't discount the value of lumber from old buildings and old discarded furniture. Sometimes you can find the most beautiful sounding wood in abandoned buildings and on scrap heaps. Also try antique stores. Look for damaged furniture that the proprietor has pushed into a back room and forgotten. Old table and desktops can even be cut up to make the thicker pieces of your cajón. 

Depending on your woodworking skills you can build a cajón with whatever joining scheme you're comfortable with. If you're really good, you can fasten the sides and tops with dove-tail joints. This makes for some beautiful work You can also glue the sides and top together. You can screw it together, nail it together, or whatever you like best. You can pad the top (seat) if you want - it will certainly make the seat more comfortable. It doesn't make much if any difference in the sound. Your butt will serve to deaden the top anyway.

There are several ways to add a snare effect to your cajón. There are some add-on devices that can be attached to the cajón to create a snare effect. Another way to do this is to add 4 paired screws inside one of the thinner faces of the box and attach 4 steel guitar strings between each pair of screws - the unwound ones E, B, or G.  Tighten or loosen the strings to get the snare sound you're looking for. 

As you can see there's a lot of room for creativity in assembling your cajón. Check out the references below to get further information before diving into your project. They might suggest some ideas you can use to get just the right sound you're looking for.

© 2023 by Tom King

References:

1. https://www.instructables.com/Adjusting-a-Cajons-Snare/
2.  https://cajonbox.com/2012/03/31/tuning-your-cajon/
3. https://www.fuelrocks.com/how-to-build-a-cajon-with-guitar-strings/
4. https://lousondrums.com/products/floating-external-snare-system-for-cajon-and-cajontab