Monday, April 27, 2009

Or Scarfing....

Thanks to Jim Ledger from the Wooden Boat Forum for pointing out:
What about the plywood end grain in the butt? 
What about the flat spot in the panel where the thickness is doubled?
What about drainage on the bottom of the boat?
What about the ugly butt block showing on the interior?

And to kc8pql  for his comment:
Suck it up and do proper scarfs. You've worked to long and hard to chicken out now.

So I tried scarfing, or at least, I've cut the scarfs. 

I just stacked the 2'x8' sheets of ply with each 2½ inches back from the next, then I ran a power plane down the steps. I had a scraficial peice above and below as I've read that the top and bottom ones don't turn out so well.

Now I have to either
  • Glue them and put them on the boat.  or
  • Put them on the boat and Glue them
Handling 8 foot parts seems easier, but I am concerned about how well I can join the scarf when the ply is sitting on a curve.

I'm leaning towards gluing them in the kitchen/dining room (only dry place that's long enough) overnight on a friday and fitting them on a Saturday.

Wish me luck.

Wednesday, April 22, 2009

Butt Blocks

I have after much consideration decided to use butt blocks.

My reasoning is that I can do the but blocks in place so 

  • I don't have to store the 16 foot scarfed panels
  • I can manage 8 foot panels all by myself without calling in help.
  • From other Builders work, butt blocks are indistinguishable from scarfs in the end product.
However, my smallest screws are 1/2 inch I suspect that they will just project through the two layers of 6mm ply. 

I think that judicious use of a file / dremel may resolve that little detail. 

"planking"

Can you really call it planking when you whack on great plywood panels ?

Regardless, the planking has started. Cutting a 4'x8' sheet of ply* into 2 2'x8' sheets is not trivial unless you happen to have a panel saw. 

To do it on a table saw, you really need extended rollers to allow you to control it. A typical circular saw is a little big and heavy for cutting 6mm ply.

So..... More Tools!!

I got an 18v trim saw. This one was a cheapo special, against my better judgement, but I reasoned that I'd only need to cut a few sheets, and I may never use it again. When will I learn ? The Battery won't hold a charge overnight, but freshly charged it's not bad. 

To avoid massive breakout on the ply, I make the first cut about 3mm deep, half way through the plywood. This means the blade is exiting the wood moving forward rather than up. The plywood is supported by the wood in front of it, no breakout. Then I follow the same cut with the blade just through the wood. This is easier that you might think. The saw is small and easy to control with one hand.

The result, at the cost of a little extra work, is a nice clean cut.

So I now have the first two panels clamped into place on the frame.  The fit looks really good. Of course these are the aft panels. It's the fit at the pointy end that's difficult.

(*2440mm X 1220mm doesn't metric make things easier?) 

A sense of Urgency

We are bringing forward the building of an extension onto our house.

Unfortunately, where the boat is now sitting is about where the new dining room window will be. 

So I need to get the boat to the stage where I can flip it.

I'm guessing that if I finish the ply skin and then glass the hull, I can flip it and move it. Later I'll need to flip it again to paint it, but I can live with that. 

I need to think about how I will support it when I flip back it for painting, or I suppose I could tilt it up at 60deg and paint one side, then go around the other side and do the same.

If I go to flip it back over for painting, should I wait to put on the deck until I've righted it ? Or will the deck give it better rigidity to avoid damage in the flipping ?

It's a Glen L 14, so the extra work in flipping it twice is not a show stopper.

Anything I should know before I embark on this course of action ?

Monday, April 20, 2009

ToDo List

  • Cut & fit Plywood Skin
    • 4 panels
    • 2 of 2x16 foot, 2 of 3 x 16 foot - I have to scarf join 8 foot boards.
    • Fit transition joints
    • Glue & Screw into place
  • Putty the screws.
  • Fair Hull.
  • Epoxy glass the Skin.
  • Paint it.
  • Flip it,
  • Some internal framing 2 x 9' x 3 inches each side.
  • Blocks for the coming (I want to round it at the front, even though the design is simply square.)
  • Paint inside
  • Seats + Varnish or Deck Oil
  • floorboards + Varnish or Deck Oil
  • Plywood deck
  • Coamings
  • Mast Step.
  • Paint deck.
  • Make up mast & boom, including sail track in mast & sheave for Mainsheet Halyard.
  • Varnish mast & boom
  • Fit mast hardware.
  • Make up rigging.
  • Make up centerboard, glass
  • Make up rudder, glass, paint.
  • Attach cleats, blocks, fairleads, rigging, sail tracks.
  • Carve name plates.
I suspect I should be done by Saturday June 6th 2015 
;-)


Sunday, April 19, 2009

Fair Enough....

The laminates worked just fine, it's more or less ready for the plywood skin to be attached.

I can see a few places where the thickened epoxy may go on a little thicker. But in general it looks good.

Given that it's a family dinghey with a hull speed of 5 knots, and I'm not likely to be out in weather where it might get up on a plane* I think it's fair enough.

*Has anyone ever got a Glen l 14/15 on a plane?

Tuesday, April 14, 2009

Detailed Bevelator Pictures


I cut some wooden blocks to just fit inbetween the vertical guides.


 I drilled a hole for the bolt - this needs to be very precise. 


When the wood is bolted very tightly in place, you put the whole lot down on a flat surface, and screw in the aluminium strip. I've shown the result here. You need to do it in place to get it any way accurate.



You can see a small gap on the right of the strip - the plastic guides on the planer sit there.

This is accurate to about 1°

Sunday, April 12, 2009

Bevelator 1000 Pictures and Update

The laminations on the chine are in place, I will leave them till at least tomorrow to completely dry. Then I will mark the fair curve and trim away. I set up a batten to follow a fair curve, and all seems well.

I finished the heavy work on the second chine, and on the keel using the Bevelator 1000, shown here. As I described before, I've bolted an aluminium strip to the side of the planer. The strip rests on edge against the chine when you are doing the keel, and vise versa. 

This really does make light work of fairing the chines and the keel. It is not perfect, but it gets you into the ball park real quick. A little work with a Jack plane will finish the job now that the bulk of the wood has been removed. It's only off by about 1°.

The shop vac makes life a lot easier. There's about 2 buckets of shvings that are Not all over the garden. The Bosch in the picture has a switch so that it can take a vacuum on either side. That makes all the difference in the world. 

Oh yes, the planer goes through bronze screws just the same as Oak, there's not even any different sound (at least none I can hear over the shop vac, and while wearing ear muffs)

Thursday, April 09, 2009

Laminations

So, last night, under the glare of a 500 watt site light, I added the two laminations to my chine. I used microfibres with the epoxy this time.

I think they will be better as a glue, fiberous and all that.

I see some careful consideration as I mark up the curve that I want to fair the lamination too. Some serious thinking, measureing, holding plywood in place to see how it will all fit together.

Given the surface area available to glue these things up, and given that the oak should all expand and contract in the same direction, I have no fears regarding Oak & Epoxy.

Time I guess will tell.

Monday, April 06, 2009

Thanks Harvey

Just a quick note say Thanks Harvey.

The band saw made life easy for cutting 3/8" thick laminates from 2" Oak stock.

I replaced the rubber drive band, and the old blade, and added a new fence, total cost, a whole lot less than a new band saw.

It's such an innocuous machine, hardly as noisy as the Shop Vac when it's just running.

(For everyone else, Harvey had an old Band Saw in his workshop that he donated to my boat project)

Next I'll glue the laminates into place to build up the chine near the bow, and then use a batten above and below the chine to mark out a fair curve. A little work with a power plane, followed by a long sanding board and I should be back in business.

Thursday, April 02, 2009

That was a PITA

First, I will refer to a previous post boats-are-easier-than-carpets

I decided that it would be better to remove the first laminate, and replace it with a correctly sized one, rather than try to just add more laminates and fair them down.

There is a concern that White Oak does not Glue up well with Epoxy.

I am no longer concerned about this. My Epoxy glues my White Oak just fine.

The only way to remove the laminate turned out to be cross cutting it down to the glue line every 1/2 inch or so, and chipping it out with a chisel, just like cutting a housing for a lap joint.

Even doing this, in most places the wood did not come off at the glue line, A sander with 80 grit will tidy up the mess this weekend.

I used some scrap ply to see how much extra material I need on the chine to ensure that the side and bottom planking meet at most at a 180 degree angle. It's about 5/8"

At least I think know what I need to do now.

I suspect some more time in the Thinking Chair before I set to it.