Biscayne 22 by Bob Perkins 5
41. I'm finally at the front - It's been a long time coming.
42. Planking the first layer took me ~80 construction hours. Each plank is hand fit. I could glue up about 4 at a time, wipe up drips etc... I try to work as neat as possible. Removing uncured drippy epoxy is a lot easier than trying to chisel off the hard stuff. Crawling inside got to be a bit tiring too.
43. All of the frame alignment and fairing paid off. Each plank lays flat on all the surfaces (yay!). The second layer will go a lot faster since a tight fit between planks is not as necessary.
44. My first attempt at vacuum bagging went very well. A couple of small hitches - I used System 3 slow epoxy - which is too slow. The shop is at 56 deg. Need to use Medium hardner for now on.
45. This pump arraignment (from joewoodworker.com) has a pump, vacuum reservoir, vacuum switch, gauge and power switch. It will pull up to 24"Hg and auto cycle on when the vacuum drops to 19"Hg. It works very well.
However, it was totally unnecessary for this type of work.. I have a 4.5 CFM pump. I wish I had a 10CFM and a 20CFM would have been a dream. A continuous duty pump is all that is required with as much CFM as you can afford.
Think of a vacuum pump like a bilge pump, you can have a 6" hole in a boat - if the bilge pump can push the water out faster than it leaks in.. the boat floats. In vacuum bagging, leak control is where all the work is.. I had to do small sections and work to seal all of the tiniest leaks because the pump was small.
The advantages are many if you decide to use vacuum. I was able to attain 20-24" Hg of vacuum in most cases. This equals about 10-12 Lbs of clamping pressure per square inch. A staple has about 5Lbs of clamping pressure per square inch. I used a lot less epoxy because I did not have to worry about voids, gaps. It is relatively easy to do once you get the hang of it.. All of the materials are easily available.
The downside is it takes longer to do and costs a bit more because there are materials that get thrown out.
46. First Section of bottom bagged
47. Total of four bottom baggings done at this point. I'm doing larger and larger areas as I get the feel of how much the pump can do
48. Here is yet another section. My largest yet at ~18 square feet. I'll try for more area when I get to the sides.
49. Second layer of vacuum bagging is complete. There is a third bottom layer. The finish layer, mahogany, will then go over the entire boat.
50. The mahogany bow planks being spiled* into place. I have a
total of 4 bottom layers here, and 2 on the sides. The sides will get
spiled in 1/8" Mahogany soon.
* "Spiling as the word is applied to boat building, is
generally not defined in standard dictionaries. Basically, spiling is a
method of fitting two adjacent planks on a boat so that the joint will
fit closely. ...From "BOATBUILDING WITH PLYWOOD", Planking
methods.