Monday, December 30, 2013

Rudder weights glued in

Tonight the various pieces I had epoxied last evening were not cured enough to sand.  I did a little hand sanding on one side of the centerboard, but needs to cure further.  Since the fairing work on the rudder halves is about done I decided it was time to epoxy in the weights, so I did that with some thickened epoxy. 


And then I did another coat of epoxy/graphite  on the two pieces that make up the centerboard case.  I coated over what I had done last night without sanding.  I think since the previous coat is not fully cured that I'll get good adhesion.


This is as much as I will have time for before Jan 1.  Happy New Year!

Sunday, December 29, 2013

Fairing rudder and centerboard

A while back I had mixed up a batch of epoxy thickened with microballoons (tiny glass spheres) and filled low spots in the centerboard and rudder.  This lightweight fairing mixture sands very easily, and can be worked by hand or with the random orbit sander.

I used some partially worn out sandpaper and a flat block to smooth some areas, and backed up the sandpaper with the large wood cylinder for some of the curves where the blades transition to the flat areas.


I found I had a few spots that needed more filling, so marked those with pencil and applied more fill there.


I found that it's easier to tell where the curve is not fair by running my hand along the surface than it is to try to spot those areas by eye.



Friday, December 27, 2013

Graphite coating

Since last update it's been more sanding and epoxy work, and there are no compelling photos from that, but here's a shot showing the second coat on the interior surface of three of the hull panels.




I had a little epoxy left over, so I experimented with mixing graphite in, and applied another coat to the inside of the centerboard case side.  I found the mixture rolled on just fine, though I will need at least one more coat to finish filling the weave of the cloth.

I understand that the graphite/epoxy mixture cures to a very hard and abrasion resistant finish. And that's just what is needed on the inside of the centerboard case where the board swings up and may contact the sides of the case.  I'll use this same mixture on the other side of the centerboard case, as well as on the centerboard itself.


For this job I used some vintage graphite a neighbor gave me about 20 years ago.  The text on the container says this is grade 402A, which is 'ground to an impalpable fineness'.


Monday, December 23, 2013

More epoxy coating

Tonight I unclamped the hull bottom and cleaned up that joint, and applied the first coat of epoxy to the interior.



And used the leftover to put the second coat on the exterior of the mast trunk and some other pieces.

Sunday, December 22, 2013

Puzzle joint clean-up

Today I removed the clamps from the hull panel glue-up to reveal nice-looking joints.  

Here's the top one with the waxed paper still on it.  The waxed paper peeled off with no problems and didn't even appear to have been used.  So that worked great.



I found it worked well to take off most of the squeeze-out using a hand scraper.


And then the random-orbit sander cleaned things up nicely.  These joints  look like they don't fit especially close, but that's because I rounded the edges slightly before assembly so things would slip together more easily.


Later on I applied epoxy to the puzzle joints in the hull bottom.  I made an impromptu foam brush from part of a roller cover and stuck it in the slotted dowel that was originally the handle for a store-bought foam brush.  That worked much better than my technique yesterday of just using the stirring stick to apply the epoxy. 


This joint is a lot wider, so I clamped it up as shown below.  The 2x4 has a slight crown in the middle, so that when I apply clamp pressure on the ends I end up with pressure across the entire joint as the board straightens out..


Saturday, December 21, 2013

Joining hull panels

This afternoon I glued up the puzzle joints in the six hull panels.  It was a tedious job spreading thickened epoxy on both sides of each joint, especially since I was out of little brushes, and had to just use the mixing stick.  By the time I got to the final joints I could tell the epoxy was starting the hardening process.


I clamped all six panels in one stack with waxed paper between the layers.  Tomorrow we'll see how it all worked out.


Mast box fiberglass

I finished up the mast box construction by applying fiberglass reinforcement to the forward face (9 oz tape) and corners (6 oz tape).


And I applied a couple scraps of 6 oz cloth to reinforce the ramp and the portion of the trunk that will eventually poke out above the deck.



And while I was at it, I reinforced the bottom sides of the box, though this was not called for in the plans.



Wednesday, December 18, 2013

First fillets


Today I made the first fillets of many to come.  I used a mixture of epoxy, wood flour, and I added a bit of colloidal silica in hopes that it would make a little smoother mixture.  Not sure if that helped.  On past boats I've just used epoxy and wood flour.


Turned out pretty nice, I think.  After this has hardened I'll install the fiberglass on the outside corners and this part can be set aside for later installation.




Tuesday, December 17, 2013

Mast trunk assembly


Tonight I assembled the mast trunk.  It's great to finally start putting something together!

It was a little bit tricky to get everything aligned and square and fixed in place while sliding around on epoxy thickened with silica.  I used a bunch of clamps, but just snugged them up enough to bring parts into place without squeezing out all the glue.


In two locations I fixed things in place with my 23-gauge pin nailer and 1" stainless pins.  You can just see the tiny holes here.  I had removed the plastic tip guard to clear a jam and forgot to reinstall it, so the pins are set a little deep.


And since I had a little left over epoxy, I used that to glue together the puzzle joint joining the two halves of bulkhead 7.



Monday, December 16, 2013

Sanding, epoxy, and fiberglass work


Since last update I've spent quite a bit of time with the sander, sanding all the parts that had their second coat of epoxy (bulkheads), and some bid ones with their first coat (seat longitudinals and centerboard case side).  

I still need to scuff up the edges by hand, but after that the parts with two coats applied are ready for installation in the hull.  After they are in place paint is the final coating.

Digging through the scraps of 6 oz. fiberglass I had from a previous kayak project, I found a piece just large enough for the inside pieces of the centerboard case, so decided to install that next.  I'll have to place an order for some more so it's on hand when I need it for the bottom of the hull.


It's always fun to see the fiberglass go clear and show the wood grain underneath as the epoxy saturates the cloth.


I also put the second coat of epoxy on the inside of the bow transom and the inside of the mast trunk pieces.  I used a section of foam roller to tip out the air bubbles left by the roller, and it leaves a pretty nice finish.


And today I sanded the second coat of epoxy on the inside of the mast trunk pieces. Assembling this will be one of the next jobs coming up, and it will be fun to be at the point of starting to put some parts together! 



Thursday, December 12, 2013

Sanding, more epoxy, first fiberglass on mast trunk


Since last update I've been spending a lot of time sanding all the parts that I've previously epoxy coated.  The power sander made a good job of the flats, but all the edges including access holes and  scuppers were done by hand.  Took some time.

Today I put the second coat of epoxy on the original parts, and the first coat on some new pieces.  It works good to hang them up on a 2x2, otherwise it would take a lot of room to lay them all out somewhere.



A couple days ago I gathered together the parts of the mast trunk to see how that fits together.


I'm going to preassemble this part, as it's easier to work on it on the bench.  I started by putting two layers of six ounce cloth on the inside where the mast will impact as it's inserted.  After that was cured I trimmed the glass.  The remaining parts of the mast trunk got the first epoxy coat today.


I had a bit of epoxy left over the other day, and mixed in some microballoons (tiny glass spheres that make sanding easier) and faired some of the rough and uneven portions of the centerboard and rudder.  I haven't tried sanding this down yet, so will have to report results later.




Friday, December 6, 2013

Epoxy coating

I started epoxy-coating parts tonight, beginning with the bulkheads.  I mixed the epoxy in a used yogurt cup (hard to find the flat bottom containers lately), and rolled it on with a West Systems foam roller cut in half.



And hung them up to dry.  There are more parts to do, and they need multiple coats.  Looks like this is how I'll be spending my time for a while!






Tuesday, December 3, 2013

Bulkhead access holes... continued

Tonight I finished cutting out the access holes and cleaned them up.  I sanded to the lines in the corners using a drum sander on the drillpress:


And then a spokeshave made quick work of bringing the straight edges down to the mark:


Following that, I sanded the sharp edges into a nice radius, so these pieces are ready to be epoxy coated.

Monday, December 2, 2013

Bulkhead access holes

I had a few minutes this evening to work on the boat, and so started cutting out the larger access holes in bulkheads 5 and 6 per the latest plans addendum.




I fired up the old Dietz kerosene lantern for mood lighting, and was once again reminded of how much heat a lantern like this puts off.  I think it could take the chill off nicely on an overnight trip with some type of snug tent rigged over the cockpit.



Friday, November 29, 2013

Trimming weight

I spent much of the day today trimming down the centerboard and rudder weights.  The top surface is not smooth as poured and if there is extra lead the halves don't fit together well.


The lead is soft and can be worked with woodworking tools like scraper, bench plane, etc., but that's a lot more work than I thought it would be.



I resorted to my old Atlas shaper to do the job.



I had to reposition the weights to get the parts that were under the clamps.  And the centerboard weights exceeded the capacity of the machine, so had to move them around a couple times.


Here's a shot of the underside of a centerboard weight as poured.  I ended up filling in some of the larger voids with fresh lead.


This whole process took a lot longer than I had hoped, and it will be good to have it all glued together.

Thursday, November 28, 2013

Lead Pour - centerboard and rudder

Thanksgiving Day in the shop - I worked today on adding lead ballast to the centerboard (22 lbs) and the rudder (2 1/2 lbs).  The latest plans addendum was published just in time.


Starting with the centerboard, I used a large calipers to verify the thickness, marking the 13mm contour so the router would not break through at a depth of 10mm.  





I calculated how much space was needed and built a template for the router out of one of the offcuts from the kit.  I fastened the the template on with 1/2" pins driven with my Cadex 23 gauge pin nailer, which worked great.  When done, the template pulled off, leaving the pins, which I pulled with a pliers.  I cut to a depth of 10mm and left an island in the middle so the router wouldn't dive in, and later put a big base on the router and removed the island.




I did the same for the rudder, but cut these only 7.5 mm deep.




I got out my little aluminum foundry and fired it up to melt the lead.




Fun to pour metal...





There must be a bit of moisture in the plywood, as the lead bubbled and boiled.  This was a much bigger issue on the centerboard pours which have a lot more metal in them.  



Due to the bubbling, there are some voids in the underside that I may fill in after I get things smoothed out and check the final weight.




So, I'm happy with this progress today!