Although I just posted the information on the fabrication of the rear flotation tanks today (December 19, 2008), this work was actually completed during the first and second week of July.
Ok, Ok, I hear you now, "Well what the heck have you been doing since then!!!????"
So since that time we went ahead and installed the tanks into the boat. I'll post some pictures and additional explanation of that process shortly.
After the tanks were installed we decided it was finally time to deal with the seats. So I cut those both out and we have completely rebuilt them. Again, I'll post additional explanation and pictures shortly.
With the seats out I had a little bit more room to work, so we went ahead and finished up the final strengthening of the centerboard trunk area. I also put the finishing touches on the forward air tank in preparation for painting. We wanted to paint it while we were painting the seats.
After we got the seats rebuilt we then set up and painted them. I'll detail that process for you in the time before Christmas and New Years. So that just about brings things up to date. We pushed really hard to get the seats painted before the weather got too cold to paint. Yes, even in Atlanta there is winter!
Stay tuned for additional updates and pictures.
James
Friday, December 19, 2008
It's Fiberglass Time
Now that we've finished our molds for the flotation tanks, I'd like to take a minute and talk about the finishing process we went through. It's very important the inside face of the mold be as defect free as possible. The gel coat will cover this surface and it will show every nick, scratch, and bump. You want the gel coat to come out of the mold as smooth as possible to minimize the amount of sanding. Also, don't skimp on the wax when coating the mold. We used Meguir's mold release wax. It goes on easily, dries quickly, and buffs out without a lot of effort. After the wax dried we sprayed on about three or four coats of Polyvinyl Alcohol (PVA). This is another mold release compound. Hopefully between the wax and the PVA you won't end up with a fiberglass structure stuck to the mold.
Finally, with all the prep work done, we're ready to start laying some glass and resin. The first part of this process involves putting on the gel coat. We used laminating gel coat so we wouldn't have to worry about adhesion problems between the coats. Since I had never worked with gel coat before it took a little time for me to understand that you get no points for neatness in this operation. The object is to get the gel coat on as fast as possible and make sure you have a good heavy coat. You want to be especially careful to make sure that you have a nice thick coat in the corners and on the flanges. These two areas are the most prone to being thin which could result in a problem when wet sanding the finished product. If you sand through the gel coat you'll have to touch it up and that leads to more sanding! And possibly more touch up...and more sanding...and well, you get the idea. After two coats of gel coat we were happy with how it looked and were ready to start fiberglassing.
Since this is July in Atlanta its hot; which means that the resin is going to set up faster than you realize. You may need to adjust the amount of hardener you're using to give you enough working time to get the glass down in an orderly fashion. We found this out the hard way with the first batch of resin. By the time Bruce got it mixed, handed it to me, and I started to wet the mold, the whole thing gelled up in the cup. So we dumped that out and mixed a new batch with less hardener. The other issue we had was that we had not pre cut the glass pieces we needed for the lay up. This was a major problem because it meant that we were scrambling to cut glass while mixing resin at the same time. This did not go well. We had a number of problems getting all that done at the same time and getting the material down on the mold in a timely fashion. The resin started to harden up on us and we ended up just stopping and letting everything solidify. We then came back, ground some areas off, and then built up another layer. The moral of this story is cut all your pieces first and have them laid out and ready to go. It will make the process a lot easier.
So, as you would expect, we did much better on the second one than on the first. I precut all the glass pieces and was able to lay the glass up in a more orderly fashion. I also did a better job getting the gel coat on - again, no points here for neatness, just get it on in a heavy coat. The net result of this experience was that the second tank was about a full pound lighter than the first one. And of course it looked better as well - even if no one will ever see the inside of it!
Finally, with all the prep work done, we're ready to start laying some glass and resin. The first part of this process involves putting on the gel coat. We used laminating gel coat so we wouldn't have to worry about adhesion problems between the coats. Since I had never worked with gel coat before it took a little time for me to understand that you get no points for neatness in this operation. The object is to get the gel coat on as fast as possible and make sure you have a good heavy coat. You want to be especially careful to make sure that you have a nice thick coat in the corners and on the flanges. These two areas are the most prone to being thin which could result in a problem when wet sanding the finished product. If you sand through the gel coat you'll have to touch it up and that leads to more sanding! And possibly more touch up...and more sanding...and well, you get the idea. After two coats of gel coat we were happy with how it looked and were ready to start fiberglassing.
Since this is July in Atlanta its hot; which means that the resin is going to set up faster than you realize. You may need to adjust the amount of hardener you're using to give you enough working time to get the glass down in an orderly fashion. We found this out the hard way with the first batch of resin. By the time Bruce got it mixed, handed it to me, and I started to wet the mold, the whole thing gelled up in the cup. So we dumped that out and mixed a new batch with less hardener. The other issue we had was that we had not pre cut the glass pieces we needed for the lay up. This was a major problem because it meant that we were scrambling to cut glass while mixing resin at the same time. This did not go well. We had a number of problems getting all that done at the same time and getting the material down on the mold in a timely fashion. The resin started to harden up on us and we ended up just stopping and letting everything solidify. We then came back, ground some areas off, and then built up another layer. The moral of this story is cut all your pieces first and have them laid out and ready to go. It will make the process a lot easier.
So, as you would expect, we did much better on the second one than on the first. I precut all the glass pieces and was able to lay the glass up in a more orderly fashion. I also did a better job getting the gel coat on - again, no points here for neatness, just get it on in a heavy coat. The net result of this experience was that the second tank was about a full pound lighter than the first one. And of course it looked better as well - even if no one will ever see the inside of it!
Two Lefts Don't Make a Right
By now you've read my post dealing with the construction of the molds for the rear air flotation tanks. I'm sure you were impressed with how smoothly and easily it went. Well I must confess that I left a 'small' part out of the story. This is that missing part of the story.
OK, so our intrepid molders are busily putting the pieces of the first mold together. Things are going well. We've got this down to a science. We complete the first mold and I take the patterns for the second mold and trace out the pieces and cut them out. So far so good. At this point we get a visit from my sons and my brother in law. There are lots of questions about what we're doing, how's it going, how far have we gotten, etc. The purpose of this visit is to have me finish up for the evening so we can go to dinner. So Bruce and I are answering the various questions while trying to hurry up and get the starboard mold put together. We slap some glue on it, drive in a couple of nails to hold everything and leave it for tomorrow.
So the next day, after I get home from work, Bruce informs me that we have made a small mistake......It seems that in our haste to get the second mold assembled, I managed to put it together backwards. So instead of having one port and one starboard mold, we had two port molds! I hadn't paid attention to the proper orientation and had glued it together "inside out".
How do you spell frustration! Well I knew there was a reason I had brought that whole 4'x8' sheet of MDF up to work with. So I went back to work and cut out a new set of pieces and we put them together in the correct orientation.
A word to the wise - don't be in a hurry when you are assembling the molds. Make sure you have the orientation correct before you glue and screw everything together. It will save a lot of headache if you do.
OK, so our intrepid molders are busily putting the pieces of the first mold together. Things are going well. We've got this down to a science. We complete the first mold and I take the patterns for the second mold and trace out the pieces and cut them out. So far so good. At this point we get a visit from my sons and my brother in law. There are lots of questions about what we're doing, how's it going, how far have we gotten, etc. The purpose of this visit is to have me finish up for the evening so we can go to dinner. So Bruce and I are answering the various questions while trying to hurry up and get the starboard mold put together. We slap some glue on it, drive in a couple of nails to hold everything and leave it for tomorrow.
So the next day, after I get home from work, Bruce informs me that we have made a small mistake......It seems that in our haste to get the second mold assembled, I managed to put it together backwards. So instead of having one port and one starboard mold, we had two port molds! I hadn't paid attention to the proper orientation and had glued it together "inside out".
How do you spell frustration! Well I knew there was a reason I had brought that whole 4'x8' sheet of MDF up to work with. So I went back to work and cut out a new set of pieces and we put them together in the correct orientation.
A word to the wise - don't be in a hurry when you are assembling the molds. Make sure you have the orientation correct before you glue and screw everything together. It will save a lot of headache if you do.
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