Monday, March 31, 2014

The Utility: More progress reveals new trouble spots

More fairing. This time, it has been a matter of fairing the overhanging edges of the side planking down to meet the chines.

For the most part, I have been doing this with a power sander and with a sanding block, along with occasional help from a hand plane. I also bought a “multi-tool” oscillating saw to trim the planking up forward, where accurate fitting along the mid-width of the chine is required.

A large portion of this work is done. However, as I look down the length of the chine to check for “fairness” of line, I’m seeing some new trouble spots. It appears I’ve got a couple of low spots in the chine, particularly on the port side... the dreaded “humps and hollows” mentioned in Boatbuilding With Plywood

Once I get some remaining areas fully sanded, I’ll be able to assess the problem more accurately. However, it’s already looking like I will have to add some more strips of wood to fill these areas. That means more fairing. (Yaaay!) Oh well, it will be for the best if so.

The dreaded "humps and hollows" are plainly visible along the port chine.

To a lesser degree, the same issues are visible along the starboard chine.

Fairing progress at the transom. I still need to sand away those Raptor staples.

Still need to encapsulate the limbers before planking the bottom of the boat.

Also need to encapsulate the sole supports before planking the bottom.

Test-run of the transition joint. I'll probably move this forward an inch or so.

Test-run of the transition joint. I'll probably move this forward an inch or so.

Here is the cut I made along the forward curve of the chine, using an oscillating "multi-tool" saw.
So far, I've been very happy with the Porter Cable multi-tool I bought. It is very easy to use.

Tuesday, March 11, 2014

Raptor stapler meets transom

The Raptor stapler I ordered came in yesterday. I took it home and put it right to work.

Raptor CT-6000P Compression Stapler
Raptor CT-6000P compression stapler
The model I’d ordered is the CT-6000P. It is a manual compression stapler, not one of the fancy air-powered tools. However, I didn't have to handle this stapler long before I got the impression that it is better made than similar tools I've seen at big-box stores. That’s reassuring, given that the CT-6000P isn’t exactly cheap.

It is made specifically to use the proprietary Raptor composite staples. Those aren’t exactly cheap, either. The tool, a box of 9/16” staples, and shipping totaled a little over $125.00. Question is... is it worth it?

So far, I think so.

The first thing I did, of course, was to try the stapler out on the closest object available. I tried to drive a staple through a sheet of 1/4” eucaboard on a work table into the 3/4” plywood table top. That didn’t go so well. Not only did it not penetrate the eucaboard well, it sent shattered pieces of plastic staple flying everywhere. The second shot didn’t fare much better. I crossed my fingers and hoped that 1/4” Meranti plywood would be a different story.

It was.

I tried the stapler out on several pieces of scrap plywood, adjusting the tool’s set screw a little as I went along. It worked very well, easily tacking Meranti scraps together, as well as into a piece of 3/4” pine plywood. The 9/16” staples did not seat fully, but sufficiently enough to hold two layers of plywood together long enough for the epoxy between them to cure. That’s all it needs to do. In fact, a little bit of extraneous staple remaining above the wood surface should make it easier to break off & sand away. That’s the whole point of using composite staples in this project: to leave little or no visual evidence of fasteners.

So, confident in the knowledge that it was going to work, I decided to go ahead start mixing epoxy. In the end, I had to mix 3 batches. It took far more epoxy to cover the surface area of the transom, as well as the mating surface area of the transom cover, than I’d estimated. Once again, the kitchen scale was indispensable in this process. I took the advice of another builder, and enclosed the scale in a large freezer bag to protect it from epoxy drippings.

With both mating surfaces covered, it was a relatively simple matter to clamp the transom cover into position. The Raptor stapler did its job nicely, tacking the 1/4” Meranti plywood onto the 3/4” Douglas Fir plywood beneath it. For safe measure, I added clamps all the way around. 

The transom cover... glued, stapled and clamped.

The next step will be to shear off and sand away the composite staples.

19 gauge, 9/16" Raptor composite staple.

Top of the staple snipped off...

...and sanded away.

Monday, March 10, 2014

Next stop: Transom.

The side planking is all on now. So, the next step is to cover the transom with Meranti so that it will match the deck.

First, I made a posterboard template of the transom. Then I positioned the template over an attractive grain pattern on the Meranti plywood. I traced the template, then drew a secondary line extended 3/4” outward from the tracing. I cut to this secondary line so that my transom cover would be oversized sufficiently for me to fit and position it as needed.

Posterboard template & oversized transom cover.
The next step will be to attach it.

To help with this, I have ordered a Raptor stapler and some 9/16” Raptor staples. The Raptor staples are plastic. So, you can simply sand off the extraneous end of the staple once the stapled piece of wood is bonded to the sub-layer. This should leave little or no evidence of fasteners, as would be the case with screw heads, etc.

That’s the idea, anyway. The stapler should be here early this week. I’m looking forward to trying it out.

 Side planking trimmed at the bow.

Side planking trimmed at the bow.
Fairing progress on the side planking.

Monday, March 3, 2014

The Utility: attaching the last of the side planking

Finally, the time came to attach the remaining 7 feet of planking to the port side. 

I prepared for this on a Saturday afternoon, removing all of the screws and setting aside the planking. That sounds simple enough, until you take in to consideration that’s roughly 80 screws, all driven (and removed) by hand. I don’t bother with the power screwdriver anymore... the silicon bronze screw heads are simply too soft. 

Planking removed, waiting for epoxy.
The boat framework, waiting for epoxy.

Stem & bow... drilled and ready.
Drilled holes along the upper part of the chine log.
The port side butt block, waiting for the planking.

On Sunday, I launched into the task of attaching the planking on for good. I had everything staged: Mixing cups for 2 batches of epoxy, kitchen scale, plenty of Silvertip Gel Magic on-hand, mixing sticks, chip brushes, an awl for initial alignment of screw holes, screwdriver, rag, putty knife, extra latex gloves, and of course... plenty of clamps. 

Kitchen scale, epoxy & application tools ready-to-go.

After my previous experience with having to mix a second batch of epoxy unexpectedly, this time I pre-planned to mix two batches: One for the framework, one for the plywood. This worked out nicely, with a minimum amount of waste. 

First, I removed the remainder of the forward supports for the construction form. It would be difficult to access all the screws to do this after the planking was on. If I didn’t remove it now, I wouldn’t be able to take the hull off of the form later. What an unpleasant discovery that would be. 

Next, I lightly sanded all the mating surfaces to remove the “rim” around all the holes that I drilled. I wiped the sawdust off of all the surfaces, and mixed the first batch of epoxy. After applying that to the butt block, sheer clamp, chine log, forward frame, and stem, I mixed the second batch and applied it, (globbed it on), to the plywood. Then, I clamped the plywood roughly into position and aligned the first couple of holes with the awl. I then drove a couple of screws, and satisfied with the alignment, clamped down the rest of the plywood. Then I drove the rest of the screws. 

Once that was done, I used the putty knife to scrape away excess epoxy where possible. I used some of the excess to fill screw holes & threads. 

When working with epoxy, I wear two layers of disposable latex gloves. I change the outer layer frequently to reduce mess on tools, etc. 

 The whole process went very smoothly, and took roughly two hours. 

The rest of the port side planking, finally attached.
Butt joint, after completion.

The port side planking — glued, screwed and clamped at the stem.

The next steps will be to fair the overhanging edges of the planking down to the chines, and to add a layer of 1/4” Meranti onto the transom. After that, a little more encapsulating work on some small inner parts. Then I can start planking the bottom.