Timeout Life...I Have A Boat To Build

I had to take some time out from life to spend with Summa. She was becoming jealous and I honestly do not blame her. I picked up where I left off and I must say that after a few hours in the garage with Summa and Philip Glass, I was in bliss.

I had to finish the doublers for the transom and bulkhead 2. I mixed up some epoxy and quickly bonded on the doublers.

 

After bulkhead 2 had cured, I cut the remaining upper section of the access hole (matching the upper contour). I left a small step around the access hole with the doubler to help properly seat the hatch.

I also finished laying out the transom doubler for the tiller hole and was able to prep that for bonding. For this doubler, I bonded together two scrap pieces of the 6mm plywood sheet. I will show a picture later after it has been bonded to the transom.

I was then ready to start the bottom panel scarf joint. This is somewhat of a milestone for me. It is also somewhat intimidating considering I only have two remaining sheets of 9mm and thus no room for error. I decided to try and 'freehand' the joint using a hand plane instead of using a powertool with a tool. I have seen this joint completed using a hand plane on a couple of other Navigator blogs and it looked straight forward. This is my first time to use a hand plane and what better time to learn than with a little applied pressure. 

The recommended taper ratio was 8:1. I marked it out and clamped the sheets together with an additional two sheets of 6mm to provide some additional support/stiffness.

 

I adjusted the plane and went to work. It was actually quite easy and seemed to be easy to control. I was afraid I would somehow gouge the plywood but I proceeded slowly and was able to create a nice taper.

 

The nice thing about working with plywood is that the layers aid you in remaining straight when scarfing the joint. I had about 70 percent of it complete after about 20 minutes. 

 

I then noticed a small gap in the center of the panel between the two sheets. You can see the gap in the below image. This was due to the slight curvature that developed from the way the plywood sat on the jig.

 

To remedy this I used a couple of 2x4's and clamps and was able to finish off the joint. I then used a finishing sander to smooth the two surfaces. 

 

I was now ready to bond the two together. I used epoxy with a silica thickener. This made the epoxy almost like a paste and I applied one layer across the joint. I will go back after this has cured and apply another layer to both the upper and lower bond lines.  

 

I placed one sheet on top of the other and took a quick pic showing the upper bond line. Not bad for a novice.

 

I then quickly covered the joint in wax paper and then applied pressure using a couple of sets of 2x4's and clamps. I screwed the bottom 2x4 to the jig to keep it level. The diagonal 2x4's and clamps required a little help from the wife to set up. Looking back I wish I had used a slightly smaller angle relative to the board normal to apply more pressure across the middle of the joint...hindsight is always 20x20.

 

I will let this cure and then apply another layer of epoxy/silica mix to the upper and lower bond line. After a little touch up sanding I should be ready to go....bliss.

Dusty Doublers

I made very little progress this weekend but I did get to break out the Douglas Fir. The Douglas is stored underneath the jig so I had to knock off the dust. I did not do a very good job as you can tell. 

I started to cut out the doublers for the Transom. I was able to get the top and bottom doublers cut but ran out of time for the sides....

 

I had been using the thinner Bosch T101AO blade up to this point but had to switch to the T101B for the thicker cuts. I was getting a lot of waviness on the cutting surface with the thinner blade. I tried changing the feed and blade speed but it did not help. I changed to the thicker T101B and the cuts were nice and smooth.

Documented Progress

It has been slow but I do have proof that a boat is being built. A few detailed assemblies after a few weeks of work...

 

A little early morning work being completed by flood light in the garage...

 

 Most of the doublers for bulkhead 2...

After a few more weeks, we have what looks to be the makings of a Welsford Navigator. I had to lay it out on my driveway to get a feel of what it is starting to look like...

Next on my list are to finish trimming the bulkhead 2 doubler, constructing the centercase (side panels shown), doublers for the transom and the scarf joint for the bottom panel. Ahh Progress....time for a beer.

That Sticky Stuff

I did a little bit of research on the different types of epoxies (west system, progressive, system three, marinepoxy, etc) mainly looking at cost. A coworker of mine suggested Progressive Epoxy (Basic No Blush Marine Epoxy) that he used on some repairs on his boat. It was relatively cheap and had a good reputation. Here is the website that has a lot of good information for those interested.

http://www.epoxyproducts.com/

I thought about it but ended up going with Marinepoxy sold by Duckworks. It turned out to be a little bit cheaper and was recommended by some previous Navigator builders. It has a 2:1 mix ratio and three different hardener speeds (slow, medium, fast). Only being a novice (at best) boat builder, I felt this was the best way to go. I ended up getting the 'Navigator Epoxy Kit' for $260. It included 3 gallons of epoxy, fiberglass tape/cloth, wood flour, and silica thickener. Here is the link:

http://www.duckworksbbs.com/supplies/kits/jw/navigator/index.htm

I also purchased some stainless steel hardware, pumps for the epoxy and 8" deck panels for Bulkhead 3. My fellow coworker was nice enough to give me some tongue depressors that he had left over from his boat repair. Here are a few pictures of all the new goodies....

 

 

Slow and Steady Pace

It has been a while since I have last posted but do not fret....I am still working. Slowly and quietly behind the scenes. I have been cutting out all the bulkheads and frames over the last few months while putting in a little overtime at work, (most importantly) enjoying my beautiful baby girl (and future engineer/scientist/philanthropist/athlete) and trying to avoid the Texas heat. I have also been doing a little behind the scenes research on epoxies and table saws and would like to share some of my findings...

I'll start with table saws. I will soon need to rip a lot of wood for my stringers and I think I would like to accomplish this myself with a table saw. I have always wanted to own a table saw and think that it would be an excellent tool to have in the garage. I do not have a lot of room left in the garage (with the boat and the Volvo) so I have decided to go with a portable table saw. I am not an expert by any means and I am hesitant to pull the trigger. I decided to do a little research first to calm my nerves. If any of you have nay additional suggestions then please chime in and email me...

I am leaning toward the Dewalt 745. It has a 15 Amp motor (seems to be standard for these size saws) and a 10 in. blade and comes highly recommended. Here is the Dewalt site...

 http://www.dewalt.com/tools/machinery-portable-table-saws-dw745_2.aspx

I found a few interesting articles comparing this saw to the Bosch GTS 1031 and they are definitely worth checking out if you are also interested...

http://www.thisiscarpentry.com/2012/01/20/portable-saws-bosch-or-dewalt/

and

http://www.thisiscarpentry.com/2011/11/18/dewalt-portable-table-saw/

The new guard systems are quite appealing considering the first thing I think of when I think of table saws is (kick back) safety. I had a professor in graduate school who cut off his thumb using a table saw. He had it reattached and I watched as he made progress using his thumb throughout the semester....I would like to avoid this if possible.

And the research continues...

Blades...Who Knew

While I still have a chance (before returning to work) I have been continuously cutting out the many bulkheads/frames required. I have also been learning about a multitude of things along the way...

I ended up purchasing a Bora Cutting Guide for $40 at Lowes thinking that this would be the end-all solution for straight cuts with my jigsaw...the idea was perfect. As you can see in the images, the guide has a quick clamp with rubber fittings to secure it in place. The first difficulty I encountered was the setup time required for the level of accuracy required. It took quite some time to setup the guide for each cut and with hundreds of cuts looming...I think that I may save its use for very long straight cuts. Also, the guide is limited to angles less than 22.5 degrees. This also made it somewhat cumbersome to use.

I also spent some time learning about jigsaws and jigsaw blades. Turns out that a Swiss engineer by the name of Albert Kaufmann invented the jigsaw/jigsaw blade. He did this while working at Scantilla AG company by simply replacing the needle on his wife's sewing machine with a blade....interesting. Apparently Scantilla was later taken over by Bosch and there you have it. 

I am also learning that there are many different types of jigsaw blades...wood, metal, etc. I currently have three different types of blades (Bosch) in my possession...T101BR, T101B and T101AO. T101B and T101BR both have the same number of teeth per inch but the tooth orientation is simply reversed. This allows for nice smooth cuts with less splintering either on the top or bottom of the cut (T101B - bottom and T101BR - top). The smaller blade T101AO has a larger tpi, is thinner and is slightly off centerline. This coupled with orbital blade motion apparently allows for smoother cuts around curves. The teeth on the T101AO blade are oriented straight out. 

All of these blades have what is called 'taper ground back teeth' that allow for an almost splinter-free cut. According to what I have read, they cut at a slower speed. This is why I may have seen the splintering in my previous post. I was using full blade speed with a very high feed rate. Interesting stuff...at least to me, the novice.

Patience Is A Virtue

Well, I have yet to finish drafting all of the frames but I could not wait any longer to do some actual cutting. Even though the thought of cutting into this expensive plywood is somewhat unnerving, I decided to go ahead and cut out some of the 9mm frames that I have already drafted and that have simple geometry. A few interesting things happened while doing this....

Now, I will be the first to admit that I am not yet a true woodworker so these findings may seem trivial to those with more experience....

I decided that in order to make the process a little easier, I would cut the large plywood board into a more manageable piece that would allow for easy manipulation to cut the smaller frames. I made the cut very quickly with the jigsaw and found that the outer lamina splintered along the curves (as seen in the image). This is a little concerning. I had read that Meranti plywood is prone to splintering and have thus confirmed it. I will have to pay attention to grain direction and also adjust the jigsaw blade speed and feed rate when I cut curves on the actual frames. I am also wondering if a small coat of epoxy on the outer lamina around the curves would also help prevent this from happening.

It also turns out that my freehand attempt at cutting straight lines with a jigsaw is not as good as I thought it was...overconfident from my sailplane days. It seems a guide is in order. I think the frames I cut will suffice but being somewhat OCD about things like this I will not continue until I get a guide. I am looking at a Bora Cutting Guide to help alleviate the issue. I know that a peice of straight metal and a couple of clamps would work but the thought of a quick release cutting guide is enticing.

All in all...I have my first frames cut...exciting stuff!