Some Itch and Scratch (Also, 3M™ Scotch-Brite™ Grinding Disc Kit product review)

There was another beautiful day in the State of Maine yesterday.  Sunny and 55 in January is not normal, but I will take it!!!!  It allowed me to do the fiberglassing that I did not get accomplished on Sunday.  Even then, I did not get all of it done, but I made good progress, and at least have the bulkhead tabbed into place, but I am getting ahead of myself here.

This is a technique that I saw in Don Casey's This Old Boat, and I thought that it looked like it is a good idea.  What you are looking at (left) are the tabs that I cut out of the bottom of the bulkhead.  This allowed me to pass fiberglass tape (1 and 1/2 inch fiberglass fabric) through the holes and have a solid, mechanical connection of the bulkhead to the hull.  This means that the bulkhead has more strength in place.  When it was tabbed into place by Columbia Yachts, they only ran a piece of glass cloth about 2 inches up the side of the bulkhead, and 2 inches were on the hull for the entire length of the hull-bulkhead joint.  While this is adequate (it lasted 49 years) and cost effective for mass production, the strength factor is not as great as it could be.  I did realize that after I had started tabbing the bulkhead into place that, should I have to do this again, it is going to be a COLOSSAL pain to get it back out.  The hope is that I will not have to do this project again on the same side of the boat.

Before I started to glass the bulkhead into place, I had to make fillets along the base of the bulkhead.  Fillets, if you're curious, are some sort of filler material (in this case, Bondo) that softens the angle between the bulkhead and the hull to something less than 90 degrees.  The reason for doing this is because the fiberglass fabric really, REALLY does not like to make sharp bends, particularly 90 degree bends.  The fillets make the transition from plywood to hull a softer, more easily conformed to shape.  The other benefit to doing this is that there is more surface area where the bulkhead meets the hull.  Sometimes when fiberglass boats get old, they begin to show hard spots, or places where bulkheads, fixtures, etc,  have made marks or have deformed the fiberglass because of stress and time.  These areas are less structurally sound than the surrounding fiberglass.  Luckily I have not found any hard spots on the boat, which is amazing for a 49 year old fiberglass boat. 

I had to do the tabbing in sections because I could not effectively mix large quantities of epoxy resin and have time to use it all before it started to harden.  I did two through tabs at a time, which was pretty effective.  I pre-cut the glass tape, as it would make a mess trying to cut glass tape from the roll with gloved hands covered in resin.  I had to wet out the tape (completely saturate with resin) to get a good bond to the hull and other layers of glass.  I also had to take the time to make sure that there were not bubbles between the layers, as this ruins the strength of the bonds, as well as allowing for the potential for water to be trapped in the bubbles.  The final step in the process was to lay a piece of tape along the seam of the bulkhead and hull.  While I did not have the daylight, energy, or glass prepped to do this piece of the puzzle satisfactorily, I did get one piece in place, and for the time being, it will have to do.  When it gets warm again, I will take the time to cut pieces of fabric that will give me at least a 2 inch surface on both the bulkhead and hull.  I figure if 2 inches of glass was good enough for 49 years, that is what I should do in the repair process. 

PRODUCT REVIEW: 

3M™ Scotch-Brite™ Grinding Disc Kit

I do not have a cordless sander.  I was going to try to buy a corded sander, and see if I could bum some electricity off of my gracious host, but decided against it.  When I was at Napa picking up some other supplies, I noticed a 3M product.  They were drill mounted sanding pads, which looked like exactly what I needed.  I picked up a box of the sanding pads, and went on my way.  When I got to the boat, I realized my mistake.  I had not picked up the piece that the pads mount into.  I tried to fit them into the chuck of my drill anyway, but it was hopeless.  The pads, because they were threaded on the back side for the mount, would not seat in the drill chuck in a square manner, thus making the sanding pads difficult at best.  I had to go back to Napa to see what I had missed.  I found the kit, and what I thought was going to be a great kit for $20 turned into a kit for almost $50.  Not such a great deal, BUT I do have to say, for my purposes, and not having anything but a cordless drill, they were just what I needed.  Also, $50 is still quite a bit less than a corded sander would have cost me, let alone a cordless one!  The only issue I had with the sanding disks was clearance.  I was trying to sand in and around a cabinet that had been mounted to the bulkhead.  Because the cabinet was there, I could not get into some of the places I needed to with the drill/sander because it was too big.  Everywhere else I used it though, it was pretty good.  I still would have preferred to use my pneumatic orbital sander, as that is an amazing piece of equipment!!!  If you're in a pinch, only have a cordless drill (or Dremil tool or similar) then this is a pretty good product.  It will never replace a dedicated sander, or even the feel from a sanding block and piece of sand paper.  I know, I have spent a lot of time sanding fiberglass by hand.  This sanding kit from 3M was helpful, but if would have been nice to see a label on the package telling me I needed the chuck piece, rather than figuring it out the hard way and wasting some of my time.  Maybe they just expect their customers to open their eyeballs and use their brains, which is understandable, and what I should have done.  Thats what happens when you're in a rush though.  

VERDICT: 

If you can get a real sander, do it.  If not, this is a pretty decent substitute so long as you have the space to maneuver it into the places you are sanding.  Would I buy it again?  Yes.  Will I use my eyes and brain next time I go to buy a new tool?  Maybe.  We will see!  ;)