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.