Tuesday, 17 February 2015

Finished planking, fillets, sanding, fillets, sanding, fillets, sanding...

I know it's been a while since I last posted an update on my boat progress. It's been pretty hot here, and although our garage is under the roofline of our house, it's got no air-conditioning and gets very hot inside, so my progress has slowed markedly. In any case I have made some progress. Firstly the completion of planking:

Once planking finished I got down to the seriously boring task of epoxy coating, filleting, and sanding. This is still underway, and won't be finished for a few weeks yet. The interior has lots and lots of corners. I want to put a fillet on as many of those corners as I can, because it looks nice, because it makes the boat immensely strong, and because with a fillet there is no way that I can trap water.

From the bow it looks rather like a boat.

The process for filleting is to mix an extra-thick batch of epoxy and push it in the corners with a paddle-pop stick, then go over it with a larger tongue depressor to remove most of the epoxy and leave a nice clean fillet. Any bits I miss I have to sand down later. There's lots of motivation to clean it up before it goes off, as it's really hard to sand. It's slow because there's an amazing number of corners on the inside of the boat, and because I'm a bit anal-retentive. I'm telling myself that attention to detail at this point will be worth it in the long run, making painting easier and making the boat a whole lot easier to maintain.

If I try to do too much at once, the epoxy heats up in the pot, which makes it go runny, and then rapidly go everywhere but where I want it, so I have to work methodically with small batches. Anybody who knows me will know that methodical just isn't me.

I also finished off the centreboard pivot. It ended up reasonably straightforward. a 19mm diameter length of bronze rod, which fits into some turned flanges. The flanges have a groove in which a 19mm x 3.2mm o-ring sits, and the whole lot is held together by a turned cap, made from silicon bronze, and held in place with a 10-24 silicon bronze screw either end. There's no need for massive axial strength - the screw simply locates the pivot and holds the caps down, which in turn press the o-rings into their grooves and hopefully keep water out. Please expose the fillet booger.

Here's a photo showing the cap taken off, exposing the o-ring. I'm hoping this is plenty strong and keeps water out of the cockpit.

Thursday, 5 February 2015

Snakes!

So we've put two little Western Browns outside the building at work in the last two days. Might have a nest.

Saturday, 24 January 2015

Using my Mac Mini as an adblock proxy for my iPad

I really like my iPad. It's a wonderful tool for browsing the web, browsing media, reading stuff and controlling my home theatre PCs, whilst laying on the sofa or in bed. There's just one catch: No adblock, at least under Safari.

Now I don't know about you, but there's only so many "one weird tip" or "Ellen scandal" ads that I can cope with before going completely postal. The straw for me came in the form of a "vdopia" popup autoplaying video ad on mac rumours, which was not only incredibly irritating but also broke the mac rumours site.

In any case, I was desperate to find a way to browse the net on my iPad without having my eyes constantly burned out by incredibly obnoxious ads. I tried a couple of replacement browsers, but found they were even more obnoxious than the ads they blocked. The solution for me came in the form of privoxy, which is an adblocking proxy server.

This is where the new mac Mini comes in. The latest model (as well as having a huge 2TB hard drive for my media and super fast processor and video) draws a piddling 7W of mains power when idle, and are totally silent. I've had PCs that used more power than that when they were switched off. It's the perfect media server, and also the perfect proxy server.

So here's the secret sauce for getting privoxy running on new Macs running OS X Yosemite. It's based on instructions at Andrew Watters' blog with extensions to allow access from other machines on your local network (i.e. the iPads) and also to work around some Yosemite launchd weirdness:

1. Your mac needs to have a static IP address, so other machines on your network know where it is. I like to use my router to allocate IP addresses, so I set up a binding in there to ensure my mini always comes up at the same IP, but is still able to run DHCP. In my case, I run ifconfig from the terminal, and copy the mac address from the active interface, then paste that into the "DHCP reservations" field for my router using airport utility. I gave it a fixed IP of 10.0.1.101, which is easy to remember.

Note this isn't an address you can get to from the outside internet, as the router is still doing NAT. It's just for machines local to your router. Alas your eyes will still cop the obnoxious ads when you're away from your home network, but for me 90% of my net browsing is done at home, so this is good enough.

2. Now install Xcode from Apple. This is the apple software development suite, and includes compilers etc, which we'll use for compiling privoxy from source.

2a. You'll also need autoconf. The version linked to in Andrew's blog didn't work with the latest version of Xcode/os x, so I just found the newest version. From the terminal:

  • curl -OL http://ftpmirror.gnu.org/autoconf/autoconf-2.69.tar.gz
  • tar -xzf autoconf-2.69.tar.gz
  • cd autoconf-2.68
  • ./configure
  • make
  • sudo make install
I found I had to run it again from ./configure a second time because a fresh install of Xcode doesn't work until you've agreed to licence terms, which only come up when you make.

3. Add a user for privoxy, and associate them with a freshly created privoxy group.

4. Download the privoxy source, and install it:

  • cd ~/Downloads
  • tar -xzf privoxy-3.0.22-stable-src.tar
  • cd privoxy-3.0.22-stable-src
  • autoheader
  • autoconf
  • ./configure
  • make
  • sudo make install
5. Edit privoxy's config file:

  • sudo pico /usr/local/etc/privoxy/config
If you don't like pico, use whatever editor you prefer.

While you're in there, you need to change enable-remote-toggle to 1, enable-edit-actions to 1, and insert your IP address in place of the loopback at listen-address. Detailed instructions are on Andrew's blog

6. After much stuffing about, I worked out that launchd under Yosemite doesn't run the daemon when you use the RunAtLoad key. I found "KeepAlive" worked, and is more in keeping with what you want the OS to do with a daemon like this. So when you set up /Library/LaunchDaemon/org.privoxy.plist, substitute "KeepAlive" for "RunAtLoad"

7. Reboot to get the daemon running, and edit the proxy server setting on your iPad (settings->wifi) to manual, and enter the IP address of your mac, with port 8118.

Done!

Thanks Andrew, you're a champ!

Sunday, 4 January 2015

Almost done planking

With just the bow end of the top plank to do, I figured it'd be nice to show my "look ma, no screws" method of planking. It relies on the fact that the Navigator has reasonably narrow planks (hey, that what gives her such lovely lines), as I have to be able to get a clamp over the top of the plank with a bit of wood placed in such a way that it puts roughly equal pressure on the stringers on each side of the plank.

Anyway, pictures. First here's a close up of a clamp in place. If you look closely on the stringer side, you'll see a simple length of wood spanning the stringers:

Here's a view of the inside (complete with sleeping cat) showing the temporary braces. These are just held in by the clamp pressure. I've got to be careful not to get any goop on them, or else they're rather hard to get out afterwards (ask me how I know this!).

This picture is probably more illustrative, but has the disadvantage of not showing my cat sleeping on the forward thwart:

I took all these clamped up photos while test-fitting, before mixing up epoxy. When I've got a batch of epoxy going, I keep the camera well away. That stuff sticks to anything.

Anyway, it's getting to the point where it looks like it might even float. Here's the stern section, with the cockpit seats all buttoned up and all the planking done. I resisted the urge to paint out the inside of the cockpit seats. I gave it a thorough coating of epoxy and left it at that.

For the join between the aft and midships section of the top plank I elected to do a scarf rather than a butt-join. This is purely cosmetic - this join isn't hidden behind seats so I don't want an ugly lump of wood showing.

Up front you can see where the final plank piece goes. I moved the midships-bow join for the third plank one frame forward from plan - this hides it forward of bulkhead 2. I haven't done anything to hide the join for the midships-bow section of the top plank (just aft of bulkhead 4), as that's where I'll be putting the chainplates for tying the shrouds off to, and a double thickness of ply there will reinforce things nicely.

This is the view I get now when I walk into the garage. I get a lot of pleasure from seeing this every day.

Tuesday, 23 December 2014

Postage bastardry

One of the challenges I'm having is getting materials to build my boat with. I live in Geraldton, Western Australia (not to be confused with the other WA). It's about 450km north of Perth, the capital of WA. I rather like bronze, but none of the local metal merchants stock it, none of the Australian mobs I've found are interested in small quantities, so that leaves American online mobs.

I bought a piece of C220 bronze sheet from McMaster Carr recently to make bits from. So far I've used some to make plates to support the becket on my centerboard uphaul, and the cover plate featured in my last post on the front thwart. McMaster advertised a 2" x 24" x 0.09" piece of bronze for US$41.27. Expensive, but them's the brakes. I ordered it, and it showed up a week or so later. The cost on my card: AU$106.72. So the shipping was just as expensive as the metal.

So I asked on the woodenboat forum if there were any alternatives to McMaster, and found online metals. They will cut sheets to fairly arbitrary sizes, and are at least upfront with shipping. I tried a 12x1x0.125" piece of 220 bronze. US$14 for the bronze, but a staggering US$123 for shipping. Just for fun, I tried a 1x1x0.125 piece:

Yup, US$123 to ship a poxy couple of grams of bronze. Bastards.

Monday, 22 December 2014

Getting the insides of the seats sorted before sealing things up

Lots of little jobs. I've done 2/3rds of the third plank, and am starting to have to think hard about the order of events, so I don't make it impossible to do things.

First thing first, I finished off the front thwart. That meant making mounts for various pieces of gear; a 180W sinewave inverter for charging electronics from the battery, an AIS transponder, and an antenna switcher so the AIS transponder and VHF radio can share the same antenna. I also made some access holes in the thwart, both for the VHF antenna, near the mast tabernacle, and so that I can run power and coax back to the cockpit for a radio.

In the first photo you can see where I've added rails for the gear (on the inside, alas). You can also see a little bronze plate I made to seal up the antenna port, just next to the spine.

On the other side of the thwart the hole for other cabling is visible, complete with paint run. I'll cap that off with another bronze plate. Also if you peer into the hatch you can see a power point, for charging devices.

Moving to the cockpit seats next, I added pieces of timber to locate the backs of the seat tops in between bulkheads.

Then I spent ages doing fillets, sanding, cleaning up fillets, and coating everything inside the seats in epoxy. I'm currently vacillating as to whether or not to paint the inside of the seats. I also added hard points to the seat fronts. These are just bronze rings that I turned up. The idea is that they support a rod onto which the rowing stretcher mounts (the three at the right), and the one on the left supports a rod which in turn supports raised planking, forming a sleeping platform. That's the idea, anyway.

Friday, 12 December 2014

New Apple based MythTV machine for home.

I've got a really low tolerance for television commercials. Since the introduction of free-to-air digital television in Australia, we've used a computer at home to record the broadcasts so we can watch stuff at our leisure, and skip the ads. I just installed version four of our hardware, going in a slightly different direction to the previous three.

So in chronological order, here's what I've done in terms of watching television:

  • A Via Eden 800 MHz (from memory) Mini-ITX motherboard, with power supplied via a 60W 12V power supply and pico-PSU, using a PCI DVB-T capture card and 2.5" 400GB hard drive. We ran Ubuntu on this machine, with MythTV. This machine was a complete dog. It was expensive and slow. I bought the mini-ITX motherboard because I was hoping for something that would fit in with our home stereo. It was hopelessly underpowered, despite claims that is was "good enough" to do SD content. It drew around 30W of power.

  • A Zotac ION Mini-ITX motherboard in the same case as the previous machine. This one used an Intel Atom processor and nVidia ION chipset, which had hardware acceleration that was quite capable of reliably displaying HD content. No PCI slot, so I bought a pair of ASUS U3100 USB DVB-T tuners. I added a WD green 1TB 3.5" hard drive in the space liberated by the tuner card. This one we kept for quite a while (I still have it in my donga with XBMC installed). My issues with this one were more around Ubuntu and myth than the actual hardware. It was pretty early in the days of VDPAU, so every time Ubuntu insisted on an upgrade the video hardware acceleration would break, and I'd spend a frustrating day or two googling for magic incantations to get the thing working again. Also the atom processor was quite sluggish - things like navigating menus was painful. Despite being more powerful than the Via board, it was rather more energy efficient, drawing 22W at idle and around 30W playing content.

  • One upgrade I got sick of it. I'd recently bought myself a nice macbook air for my study, so my old study machine went into the living room. This was a standard ugly desktop PC, with an Intel core 2 duo CPU and nVidia ION chipset in a normal micro-ATX form factor. It had enough power that it'd just work, VDPAU or not. I filled the case with sound absorbent foam in an effort to reduce the noise from the hard drives, and fitted some nice quiet Noctua fans and monster heat sink. I used a small 220W energy star sparkle power power supply in a bid to reduce power consumption, but only managed to get it down to 40W at idle. But it was good enough. We ran with this machine for about 4 years until it recently died.

So now on to our latest machine. Since the acquisition of the macbook air and a retina macbook pro for work, I've become quite keen on Apple hardware and OSX. The hardware is really high quality and just works. The software doesn't break on every update like you tend to get with Ubuntu. I took a deep breath and ordered a spanking new 2014 model Mac mini. I went for the mid-spec model, with i5 processor, Iris graphics, 1TB hard drive and 8GB ram. The plan was to install MythTV under OSX and be free of the linux "almost there" annoyances once and for all.

One gotcha. My DVB TV tuner cards won't work under OSX. Turns out there are no USB tuner cards that work on OSX. My only options are a "HDhomerun" network tuner, or else to build a separate (linux) backend on a different machine with my USB tuners attached to that, effectively replicating the HDhomerun network tuner but adding disk.

That's my long term plan - buy a low power box like an Intel NUC or another Mac mini, install Ubuntu on it, attach a pile of disk and hide it in a cupboard running my backend. That way it'll be doing what linux boxes like to do - running services. No need for X11, no unity, no display. I'll SSH into it when I want to do maintenance.

For now I just made a dual-boot mac mini, and am running MythTV under Ubuntu, so much the same as our previous box but much smaller, neater hardware.

Getting Ubuntu and myth running on the mac mini was a bit more of a pain that I anticipated. You'd think it'd be straightforward on mainstream hardware, but no. Here's the steps I went through, more for my own reference to reduce the random google-fu next time than anything else:

  • Install rEFIt under OSX and repartition the hard drive using the OSX disk tools to make room for Ubuntu. I chose to give OSX 200GB and leave 800GB for Ubuntu.

  • Install Ubuntu 14.04.1 from a USB key. Relatively straightforward - instructions are here.

  • Get my Apple bluetooth mouse and keyboard running. Gotchas were not pairing with the mouse, and upower being retarded and annoying me with "battery 0%" warnings every time I pressed a key. The fix for upower is rather satisfyingly to nuke it. It's not like you need power management on a machine plugged in to the wall, anyway.

  • Install mythbuntu under Ubuntu. Importantly don't install mythbuntu by itself, as it doesn't include all the tools that are needed to get everything else (bluetooth mice etc) working.

  • You'd think that in 2014, after a decade of myth, that a fresh install of the current stable version would work. Alas no. Myth development people are adamant that their product will never get widespread use, and they do this by only half setting up their database connections. Much stuffing about was necessary before the backend and frontend would talk to the mySQL database. No links for this, as by the time I found the incantations I was about ready to give up on myth entirely and didn't write stuff down. Anyway, I'm sure the problems will be different next time.

  • Go through the same Unity "legacy full screen support" pain that I've had to do ever since Canonical forced this useless desktop on everybody.

So yeah, now we've got a stable myth install running on our shiny new mac mini. The operating system is terrible, but the hardware makes up for a lot of that. It just works, and pulls a measly 11W at idle, and that's including the pair of Asus DVB tuner cards, which are about 1W each.

Alas it's no good for playing my music collection, as I was hoping for. The plan to run a separate backend with OSX frontend is still there, so I never again have to deal with unity, bluetooth, upower, or all the other user interface annoyances that accompany every linux machine I've ever dealt with.

Here's a photo of our hardware. On top of the mac mini is an apple TV, which we use for watching Orange is the new Black, and a wifi hotspot. The tuner cards are hiding under the power cable for the apple TV.

Edit: But wait, there's more! Another incantation is needed before my Apple dvd will talk to linux.

Monday, 8 December 2014

More planking, and starting to finish out the thwarts

With the second course of planking done, a little bit of thought needs to be put in to what's next, as access to various bits of the boat gets much harder as the planks go on.

Before putting the third course in, I finished out the underside of the anchor well and fit the anchor well floor. This has to be done now because, with the king plank in there, the only gap big enough to get the floor in is between the stringers where the third course of planking will go.

Similarly, once the third course is in, I've really got to do the front thwart, as the top for it only barely fits between the stringers where the fourth (top) row of planking go. Finishing out bits like this provides a useful relief from the monotony of planking, though doing fillets is one of my least favourite jobs. I've got a good recipe for the aquacote epoxy undercoat and polyurethane topcoat now. After getting the fillets to a state where they don't look revolting, I put on an even coat of unthickened epoxy with a foam roller. Then I sand that smooth with 80 grit, and apply two coats of undercoat, again using the foam roller, with a paintbrush for the fiddly bits.

The trick with the undercoat is to apply a very thin initial coat, wait about two hours for it to get super tacky, and apply a second slightly heavier coat. That way there are no runs and good coverage.

Finally I do three coats of topcoat, again using the brush to get paint into corners, and smoothing everything over with a foam roller.

Here's a close up shot showing my battery mount. The plan is to hide an Icom IC-400BB marine radio in here, with the controls on the handpiece remoted back to the cockpit, plus a Vesper marine XB-8000 Wifi AIS transponder so we can see where other shipping is, and they can see us. The 20Ah battery will provide oodles of life.

The battery will be secured with a strap and clip, so it'll stay put even if we capsize.

Here's a photo showing the lid on the thwart. I've run out of epoxy filler, so am champing at the bit until more supplies arrive, at which point I'll finish this bit off and get back to planking.

Finally I took a break from boat building to bake some stuff for a work Christmas party. Guess where the cat wanted to sit.

Sunday, 23 November 2014

Half way through planking

This planking gig is actually very easy. Much easier than it looks. You get into something of a rhythm and just turn out planks at the rate of one or two a day.

After an hour's work cutting the bevel into the top of the garboard plank on the port side with my no. 4 and not really getting anywhere, I bought a new cheaters tool, a nice Makita power planer. Where I call my Stanley no. 7 Mr Smooth, this thing is called the brute squad. It removes material at a somewhat disconcerting rate.

Here's what it does to the garboard plank.

To speed things up, I just cut my sheets into 300mm wide lengths. These are light enough for me to put on to easily mark up. I simply clamp one in place, trace along the stringers, add a bottom line with a batten 30mm down from the top of the lower stringer, and cut to shape. After a second test fit to check things, I clean up the edges with either my no. 4 or my spokeshave, depending on whether it's convex or concave, then glue it to the boat.

A little more work is needed at the bow. I decided to disregard advice and try a classical gain, cut with a saw and chisel. I start by ruling a line along the garboard plank 30mm down from the top edge. Then I cut along the line so it barely makes it through the ply at the bow, and surfaces about 200mm back. I added a second cut half way along so I could easily gauge how deep I was going with the chisel.

Then I pare away material with the chisel. As with cutting scarphs, it's actually pretty easy, as the layers in the ply guide you and let you know how deep you are.

An aside: I'm not impressed with these Record Irwin chisels. They were the best I could find locally, but they're really soft and don't hold an edge for long. At least they sharpen easily. My suspicions about soft edges were confirmed when I dropped this one on the concrete floor, and the tip actually bent over rather than snapping. Also, the rubber bits on the handles are falling apart before my very eyes. I've got my eye on some nice Veritas ones. If they're anything like my spokeshave they'll hold an edge forever (and be a real PITA to sharpen).

Next I use some 80 grit emery wrapped around a large flat file to get everything nice and flat and even. Oh, incidentally, the break from the last post is in this picture. Look carefully. If you're having trouble finding it it's about 1/4 of the way across from the left.

So here's the last plank for the second level being test fit. Of note is that I'm not using screws to pull the planks into the one below. I find that a simple piece of wood between stringers allows me to put even pressure top and bottom with the one clamp. I'm hoping that'll make the cleanup job easier when I flip the boat over.

Here's another view of the clamping process, on the other side, with gratuitous cat content:

Tuesday, 18 November 2014

Oops!

I put the starboard garboard plank on yesterday. Much the same process as with the port side. However when I went in this morning and removed the clamps, I found this:

Here's a closeup of the split. It looks like the ply has delaminated.

What to do? It looks like the split is mostly in the area where I'll be cutting a gain. Could I fill it with epoxy and clamp it up? What's going to happen when I cut the gain? I imagine taking the plank off will be a huge awful job.

Edit: On the advice of the incredibly helpful crew at woodenboat forum, I tried injecting epoxy to relaminate the ply. I figure if it doesn't work, I'm no worse off - I just cut the plank away and start again.

Here's where the shameless cheating begins. I've been trying my best to use mainly hand tools building my boat; my spokeshave, an assortment of planes and chisels, I even find I grab a hand drill in preference to the electric one. All that just went out the window. I borrowed a pneumatic paste dispenser and went at it with that. This little gizmo is unlikely to be found in most garages...

So the cheating begins by mixing up a batch of epoxy. I'm going to be forcing it down an 18ga needle, so it has to be free of lumps. I use a strainer to ensure the silica is non-lumpy and add enough to get a cream consistency.

Then the stopper goes in the syringe, and the syringe is loaded into the dispenser. This tool is designed for dispensing tiny dots of solder paste for PCB assembly. Solder paste is thick goopy stuff, much like glue.. It works by putting a carefully metered air pressure on the back of the stopper.

So the needle goes deep into the split, and I pump epoxy in. I filled it with about 1.5ml, at which point it was starting to run out.
Finally I clamp it with a piece of ply and some plastic builders film up against the face. I got good squeezage out the top, so there's a good fill of epoxy in the break.
Second edit: Here's the result after taking the clamps off this morning, giving it a wipe with 80 grit, and using the spokeshave to trim the plank down to the level of the stringer:

I reckon that'll do.