Wednesday, October 02, 2013

Sagulator

This is a really handy tool to figure out how much deflection to plan for when building wood structures:
http://www.woodbin.com/calcs/sagulator.htm

Plywood seems to do about as well as solid wood, and MDF is about 3x worse than plywood for deflection.

Sunday, September 01, 2013

Water heater burner only runs for a second

If you're lighting a water heater and the pilot lights fine, but when the burner engages, you only get a brief puff of gas, check the gas shutoff valve for the house.  Sometimes they leak, so that gas builds up in the lines.  The leak is enough to keep the pilot lit, and the built up pressure lets the burner run for a second or two, but that's all.  Sometimes the shutoff valve will stick a bit as well, so that it's still closed even though it moved somewhat.

(If that's the case for you, you should probably also replace your shutoff valve!)

Sunday, July 07, 2013

Flour smells like soap

Recently a batch of bread I made had an aftertaste like soap.  Then the next day my wife made pizza dough from the same flour and yeast, and it had the same effect.

Searching online, I read about lactic bacteria contaminating bread starters, particularly if they're too wet.  But today when I went to make another batch of bread, I noticed that the flour had the same smell.

So it looks the flour somehow got contaminated, although I don't see anything else about it online.

Thursday, June 27, 2013

Sketchup 2013 with wine in linux

Tried to install Sketchup 2013 on Ubuntu Lucid, and it kept complaining about needing to install the Windows Imaging Component.

Downloaded it: http://download.microsoft.com/download/f/f/1/ff178bb1-da91-48ed-89e5-478a99387d4f/wic_x86_enu.exe 53c18652ac2f8a51303deb48a1b7abbdb1db427f

But it claimed a newer version was already installed. From here I gleaned that I needed to move system32/windowscodecs.dll out of the way first: http://winetricks.googlecode.com/svn/trunk/src/winetricks

Then I was able to install WIC and then Sketchup.

Wednesday, May 01, 2013

Wavy shelf


Next the Son, the Stunning-Cantab:

He suggested curves of beauty,
Curves pervading all his figure,
Which the eye might follow onward,
Till they centered in the breast-pin,
Centered in the golden breast pin.
He had learned it all from Ruskin 
(Author of "The Stones of Venice,"
"Seven Lamps of Architecture,"
"Modern Painters," and some others);
And perhaps he had not fully 
Understood his author's meaning;
But, whatever was the reason,
All was fruitless, as the picture 
Ended in an utter failure.

-from Hiawatha's Photographing, by Lewis Carroll


Saturday, March 16, 2013

Shop Essentials

A friend of mine is building a treehouse for his kids, and it got me thinking about how I'd outfit an empty garage for that kind of work.

These are the basic ingredients I had in my shop around the time I started to find that I could build big wood projects start to finish without a trip to the hardware store.  It's a real milestone that feels great.

In each category, I've listed the most important items first.  I have a home depot nearby, so I've linked to the brands and items I prefer.  Lowe's has comparable stuff in general.

Stock:

  • at least 20 8 foot 2x4s (Kiln Dried, not green), should be about $2/each.  Try to pick straight-ish ones, but no 2x4 is ever going to be perfectly straight or flat.  (Pretty much every other piece of dimensional lumber in the store is going to be green (look it up) except maybe some of the redwood, which is why the KD 8' studs are my go-to building block.
  • at least 5 sheets 3/4" cheap birch cabinet plywood or outdoor/marine-rated plywood (get it somewhere like Macbeath rather than a big box store: http://www.macbeath.com/  Should cost about $30/sheet)
  • at least 5 sheets 1/4" melamine-backed MDF (should be about $30/sheet).  Watch out, the melamine edges are very sharp.  Knock down edges quickly with sandpaper
  • A 6-foot or so piece of ~1/8" thick 1" angle iron can be handy; it's super strong.  Hard to work with.


Fasteners:

  • 5lb box of 1 1/4" screws.  Use with plywood
  • 5lb box of 2 1/2" screws.  Use with 2x4s
  • 1lb box each of 1 5/8", 2", 3", 4", 5" screws



Get an organizer box like this and fill it with 1/4"x20 zinc-coated hardware.  This will cover all your bolt+nut needs.  Get boxes of ~100 each of these (50 or 25 for the longer bolts):

  • 2 boxes nuts
  • 2 boxes washers
  • 1 box of wing nuts
  • 1 box each hex bolts (aka hex cap screws) 1 3/4", 2", 2.5", 3", 3.5", 4", 5"
A drywall anchor assortment can also be handy for indoor handyman stuff.  Studfinders mostly suck.
A few feet of threaded rod (1/4-20, maybe something thicker (but then get nuts too)) is also handy.

Finishes and adhesives:
  • 1 gallon white water based latex paint
  • 1 gallon water based polyurethane, semi-gloss
  • 1.5", 3" brushes, 12" roller, pan
  • Cheap spray paint.  One can each: clear, white, black, grey primer.  
  • Titebond glue.  I mostly use original titebond, but there's Titebond II if you need waterproof.  Get one each of the 16 ounce tubes.
  • Twin tube 5-minute epoxy.  Also get a twin tube of regular epoxy.  JB Weld is handy too.  CA glue (aka krazy glue) also has its uses.  A small container of gorilla glue might also be useful, but watch out, it expands times.  Research and experiment to get a feel for what kind of glue to use when.

Clamps:
  • 8 12" 1-handed bar clamps.  They're stinking expensive, but very useful.  
  • 2-4 each of 18" and longer clamps.
Hand tools
  • 25' tape measure
  • Get a big cheap screwdriver set.  Also good to get a handful of ordinary #2 phillips screwdrivers.
  • To go with your machine screws, get a set of open-ended wrenches and a socket set.  Don't have to go crazy; cheap stuff is okay here.
  • A reasonable set of drill bits.  You don't have to go crazy on this.  A big cheap Ryobi assortment is probably fine.  Forstner bits are handy once you have a drill press.  Be sure to get a countersink or two.
  • 3 cheap box cutters
  • Automatic punch. I *love* mine.  Keeps your drill bits from wandering when you go to drill.
  • Tri-square - most come with a scriber pin, more accurate than a pencil for marking your cut
  • Big square
  • Speed square
  • T-bevel
  • 48" straight edge
  • 48" level
  • Basic framing hammer.  5 pound sledge is also handy.
  • Basic cheapish set of pliers, pipe and adjustable wrenches.
  • Couple of basic metal files.
  • A cheap set of chisels can be somewhat handy.

Sandpaper:
Watch the number of sheets you get per package, price goes down quickly with quantity.
This claims to be 80 sheets, although it's also 80 grit.  Photo says 8 sheets, but description says 80-sheet package is available online.  If it is 80 sheets, that's a pretty great deal.  Get one package each of full size sheets of 80, 120, 220 grit.
Repeat for whatever sander(s) you get.

Safety:
  • I'm partial to these face shields.  They say they're not a replacement for safety glasses, but I prefer them.
  • I'm partial to these corded earplugs since they're easy to take out and tuck into my shirt collar when I'm not wearing them.  I tend to reuse them, so a box should last you a long time.
Basic Power Tools:

Avoid cheap brands like the plague they are.  Husky, Task Force, Black & Decker, Skil, Buffalo, Chicago all suck, as does everything at harbor freight.  Don't waste your money.

Dewalt tends to be quite good.  Ridgid is okay.  Ryobi is OK but on the cheap side.  Porter Cable, Fein, Milwaukee and Makita and Panasonic, Bosch are good. 

Buy corded tools unless you're setting up a high volume shop where you'll be using tools every day.  Otherwise your batteries will be either discharged or outright dead by their fifth use a year from now.
  • 12gal Ridgid shop-vac.  Amazingly useful.  Fill up air mattresses, suck the water out of your clogged dish washer.  I love my shop vac.
  • 2 each 50', 25', 12' extension cords.  Triple-headed are handy but not mandatory.
  • Corded drill with keyless chuck. I have this one and it's okay, this one might be nicer.
  • Small impact driver.  This one is a conundrum: I absolutely love them, but they're only available as cordless and the batteries are extortion.  They're super small and light and can drive your 2 1/2" screws through a pair of 2x4s with no pilot hole, counter sink it, and then shear the head off if the wood doesn't budge.  Get these (not the double-headed ones), preferably the plastic box rather than this 5-pack, since they do wear out.
  • Circular saw (be careful!).  A modern, pricy alternative is a "track saw".  I haven't used them, but they look like a really nice solution for clean long cuts on plywood.
  • Sawhorses and adjustable height rollers.  I'm not very knowledgeable with these, but you need good workpiece support when you go to cut things like sheets of plywood
  • Drill press.  This floor standing model is the one I have and it's utterly ubiquitous; almost everybody makes them just like this.  Desktop variants look a lot cheaper and might be fine; the floor standing nature itself isn't important to me.  
  • Random orbit sander (safe, but minimize dust) and velcro sanding disks (see above for grits)
  • 1/4 sheet vibration sander (safe, but minimize dust) and pre-cut papers (see above for grits)
  • Jigsaw or sawzall.  I haven't used these much, but contractors use them a ton.  The sawzalls are more about getting into corners to cut out plumbing or cut off nails, whereas jigsaws are about cutting curves into plywood.  Not very accurate.
Optional but handy:
  • Angle grinder (be careful!) and 3 each thick disks, cutoff wheels and sanding wheels.  This is mainly about grinding through metal; cut angle iron, cut off protruding screws (leaves an ugly scar), cut through locks.
  • Air compressor & nailers.  A pancake compressor is fine for nailers and inflating things.  Air staplers and 16/18 gauge brad nailers can be very handy.  Somewhat scary; be careful.  Big contractor framing nailers are more scary.  If you want to work on cars, you'll want a compressor with a bigger tank to run a big impact wrench.
  • Compound miter saw, preferably 12" with slide.  Powered (not battery) Laser is nice too.  These are how contractors chop up a whole pile of 2x4s in seconds.  Make sure you have good outfeed support (side wings to support long workpieces on both sides of the saw).
  • Handheld belt sander.  I never used these much, but my dad loves his.
  • Router.  Be careful, they're dangerous.  This is getting into finer woodworking; mostly people go crazy at first and roundover or chamfer everything.  Linked is a small handheld one which is very wieldy.  You can get a bigger one and get or make a router table (bigger the table, the better), which can be quite useful for certain things.  (My porter cable is super quiet, which I love). 
  • Jointer & planer.  If you start getting into fine woodworking, these are what you use to clean up rough cut hardwood.  (Otherwise you pay a big premium for S4S "surfaced 4 sides" hardwood).  You can also clean up 2x4s, but 2x4s are mostly a lost cause for fine woodworking.  This jointer is meh, this planer is great.
  • Further afield are things like bridgeport vertical knee mills, which are amazing tools that everybody should learn how to use.  But they're mainly for precise metal machining.
  • CNC routers are also amazingly useful tools, but they're huge and expensive.
Expensive tools:

Don't cheap out on these.  Cheap versions suck and are scary, and you can get along without these tools until you're ready to take the plunge on a good one.
  • Bench sander.  Bench sanders are amazingly useful.  I've never found one I'm totally happy with, but don't get anything they have at home depot.  Disk sanders are generally useful, spindle sanders are useful for curved pieces.  I use the 6x48" belt sander the most (first link).
  • Bandsaw.  These are arguably safer than table saws (although the sawstop has what no bandsaw does).  They have a complimentary set of abilities to a table saw: they can cut curves and resaw really thick pieces, but the neck depth is a limitation.  Get 3tpi 1/4" wide (or 3/8") blades.  Don't get higher tpi or wider blades unless you're cutting a lot of super thin stock or doing a lot of "resawing".  There are good arguments for whether to buy a table saw or bandsaw first.
  • Table saw. Table saws are arguably the most dangerous tool in the shop.  They're powerful and useful and can be quite accurate.  They're the best tool for ripping (long cuts along the long axis of the workpiece, parallel to an opposite edge), but for cross cuts they're usually limited by how much table is between the front of the blade and the near edge of the table -- beyond that, the miter gauge is hanging off the table.  Cheap table saws are scary.  If you're going to get one, get a sawstop if at all possible, preferably the cabinet saw rather than the contractor version.  Table saws are used a lot in fine woodworking (boxes and small cabinets), less in framing/contracting.

Thursday, March 07, 2013

Light bulb aisle

Big box stores are different in Phoenix.  Here is a typical bike helmet:


















But most fascinating was their light bulb aisle, which extended across the entire length of the western wall of the store.  It had many types of bulbs I hadn't before encountered.  Most memorably:

Madness White (60W)

A dark bulb (dimmable), for over-lit rooms

A long-tube fluorescent replacement bulb consisting of a single LED element that runs the length of the bulb.  Requires twice the wattage of the bulb it replaces, and requires welding goggles while in use.

This bulb claims to illuminate only that which is false

The new "DC to daylight" bulbs, which are actually a misnomer, since they go well beyond daylight.  Primarily marketed to snobby photographers, the gamma/cosmic emissions increase lifetime cancer risk by 1%.

A line of bulbs with greater than 100% efficiency, but these require special wiring to collect the excess energy.  Otherwise they can overheat on sunny days.

Instagram-branded "Sepia" bulbs which guarantee washed out yellow illumination that fades at the edges of the room.

For climate skeptics, a bulb which emits CO2 and runs on kerosene.  (Available as a track light or for standard edison socket)

A complete line of bulbs for Tetrachromats had a demo display, but they all looked the same to me




Sunday, January 06, 2013

Making graphene

This article piqued my interest, since it suggests that making graphene can be made cheaply and easily:
http://hackaday.com/2012/03/20/print-your-own-supercaps/

That article includes links to the March 2012 paper by the folks at UCLA: "Laser Scribing of High-Performance and Flexible Graphene-Based Electrochemical Capacitors" as well as the methods paper that gives details on how they prepared it.

Turns out Rice university did it in 2011:

Their paper, "Direct laser writing of micro-supercapacitors on hydrated graphite oxide films", is behind a paywall, but here's their supplemental paper with some useful stuff: http://www.nature.com/nnano/journal/v6/n8/full/nnano.2011.110.html

Where to get the graphite oxide?

Somebody set this site up: https://graphene-supermarket.com/ but the materials are expensive.

Pretty much everybody seems to use some variant of the Hummers process to make it from graphite flakes.

These guys claim an improved and safer process: http://www.youtube.com/watch?v=sTooYDp1KD4

This tantalizing snippet claims you can make it just from glucose:

"Graphite oxide has also been prepared by using a "bottom-up" synthesis method (Tang-Lau method) in which the sole source is glucose, the process is safer, more facile, and more environmentally friendly compared to traditionally “top-down” method, in which strong oxidizers must be involved. Another important advantage of Tang-Lau method is thickness controllable ranging from monolayer to multilayers by simply adjusting growth parameters."

But the article is behind a paywall and so I haven't been able to read it: http://pubs.rsc.org/en/content/articlelanding/2012/jm/c2jm15944a

This guy demonstrates some variant of Hummers method and talks about where to get the ingredients: http://www.youtube.com/watch?v=xbalCi6S_Oc