Archive for the ‘DIY’ Category

[DIY] – 3D Camera Rig

Tuesday, July 20th, 2010

I’ve really been lagging on my blogging. Here’s a quick update.

I’ve recently found myself working out of the Beaverton office again, so late one night after finishing up I hopped onto the company’s aging, crusty lathe:

Machining stainless

These are custom captive screws for the Benro quick-release plates I picked up in Hong Kong. I’m mounting the Benro plates to a piece of 8020 1010 extrusion, and the T-slots are a little bit deeper than an ISO standard camera mount. So, for my application, a custom screw would be needed.

I’m actually pretty happy with how this turned out; the machine is old and the hand-ground parting tool isn’t the best for cutting stainless steel.

To chuck the screw into the chuck without damaging it, I took a page from an old machinist trick of slotting a nut with a hacksaw and clamping it in a 3-Jaw chuck. I started with a 1/4-20 x 0.5″ SAE button head socket cap screw.

(Note: Yes, I am aware that the standard tripod thread is a 1/4-20 British Standard Whitworth – cut with a 55 deg angle instead of a 60 deg angle. I challenge the reader to find one here in a hardware store in the good ol’ USA. A 60 deg SAE thread is “close enough” for this application with some very minor interference)

The resultant screw is a bit too long, so I trimmed it down a little bit with my motor tool.

Trimming the screws

The tool is a Taiwanese made version of the Foredom – a 600W motor on a flex shaft and a foot pedal for actuation. It takes all the standard Dremel accessories and it’ll slice through stainless pretty easily. I lined the jaws of my Wilton vice with some engineering paper scrap, and used my pano clamp as a clamping base for the tripod plate. Then, using another machinist’s trick, I put a nut on each of the screws to be cut. When removing the nut, the nut acts as a tap and cleans out any debris on the screw threads and restores the proper thread form. :-)

And BTW – at 20,000+ RPM and with 600W of power behind the disc – any slip up is … painful. Warning: somewhat graphic picture ahead:

Ouch

The wound looks A LOT worse than it actually is. I think the heat from the abrasive blade cauterized the wound – it didn’t bleed much. Digging all the abrasive grit out under running water was a different story – good reminder to be more careful the next time.

And here’s the finished rig! Now, I need to order some 3D glasses…

3D Camera rig

[Engineering] – Laser cutter failure, flour costs more than the bread

Sunday, February 28th, 2010

At work, virtually all my coworker have product development in their “DNA”. We are all creative types, who takes lots of pride in bringing a product from an idea to life. And so consequently, whenever we read about some new widget or tool, we’ve always tried to convince our boss that it would benefit the company tremendously, if only if we have the latest and greatest Super Machine 2000.

Our boss, who’s rarely wrong, always tell us that as design engineers, our time is the most valuable spent designing. “Whenever we need something, and need something quick, we just toss money at someone and have them bang it out and put it in a Fedex overnight box”.
My buddy Dave’s grandparents owns a laser engraver. They own a trophy engraving shop and laundromat down in Renton. It’s really wierd to think of a sweet old lady at the controls of an Epilog 20W CO2 laser system… but she doesreally good work. So the next time you need something engraved, check out the Puhich Dry Cleaners in Renton on 319 Main Ave. South.

I know what a 20W CO2 laser can do; it can do a lot more than mark plastic and burn through anodize layer on aluminum. There was a discussion thread on making lens cap holders, so I drew one up in Soldiworks real quick:

Laser_Fail

Here’s the test run in paper. So far so good, right?

Unfortunately, the laser engraver is running on Windows 98. It requires a firmware update before it can talk to anything past Win98, and there is always a risk of bricking a machine doing a firmware update. So we are stuck with a computer that works – abet a very slow one, with a parallel port printer connection. (I bet some of the folks I know had never seen one… they went the way of the dodo after USB became popular).

Complicating the problem is that the printer driver runs as a Corel Draw plugin. Corel Draw 8, to be exact. And even the earliest DXF that Solidworks can save the file in, the simple fillets on the drawings don’t quite come through – let alone the more complicated splines and polylines.

The example above worked okay, because the laser cut it out as a *Raster* art, instead of a vector art. But cutting in raster mode drastically drops the laser’s power output. And it’s not like you can run multiple passes over the same piece of PTFE either – the slow heat transfer of doing so just warps the plastic – and the results looked like someone tried cutting the material with a dull butter knife.

Obviously something like this, out of 3mm PMMA, will be a bit out of the question:

Bullet_Switch_Assembly.PartialDisassembly
Bullet_Switch_Assembly.Top
Bullet_Switch_Assembly.ISOMETRIC

So my options are:

1) Try to mitigate the risk of the current laser cutter’s firmware upgrade (maybe see if I can do a hardware replacement of the logic board, upgrade the computer to something snazzy, then retry the Solidworks -> laser cutter workflow.

2) Pay someone like Pololu online to do the laser cutting for me. Essentially, someone else will be eating part of my lunch if these products go on sale. Might be okay if there’s only a few parts, but I’ll have to rethink the design a little bit.

Turns out, RedWolf airsoft out of Hong Kong will happily sell me a 30mm silencer for about $US10.00. Aluminum barrel, both ends with a machined aluminum plug. They even put a 14mm CW thread on one end and 14mm CCW threads on the other, so out of the box, the dang thing will fit on just about every single airsoft gun out there.

In Hong Kong, we have a saying that “the flour costs more than the bread”. The term originated from the housing bubble days where the value of the land gets bid up so quickly that older apartment buildings prices are being outstripped by the land value of neighbouring lots, but it also applies to engineering and business where by some form of competitive advantage (and economies of scale), someone can build a product cheaper than you can even start sourcing raw materials.

Got a cool little bookmark for all my troubles with the laser cutter though…

[DIY] – Photo Chemical Machining

Friday, January 22nd, 2010

An old joke, from my college days:

“Do you know how you tell the difference between a Chem student and a Physics student?”
“The Chem student washes his hands *BEFORE* he goes to the bathroom”.

There’s some truth in that statement, especially with regards to corrosive chemicals…

Tonight I decided to give the toner transfer photomachining process another go. The toner transfer material is from PulsarFX and purchased from DigiKey Corp along with the rest of my electronics components for the bullet flight sensor and … some other projects.

First, I did up the “photo mask” in Adobe Illustrator. Since the toner side is face-down on the etch surface, I do a “transform – flip” operation to mirror the text:

Blogged at: http://www.TerenceTam.com

Top to bottom are: plain paper proof of the printout, plain paper proof of the inverted mask, and the actual mask itself, on the toner transfer paper. At a buck something per sheet, it’s advisable to do a plain paper proof every step along the way :-)

The toner transfer paper works by heat and pressure. They sell a unit for doing this, but I am not about to spend a few hundred bucks on a special laminator. So I liberated the clothes iron and set it to linens, and tried my hand at ironing on the transfer:

PrinterCart-004

Well, bummer. I had cleaned the brass piece with my Festool random orbital sander with 220 grit sand paper. Turns out a brillo pad works better.

If at first you don’t succeed, try, try again, and try harder:

PrinterCart-005

My Dad would call this “paying tuition”.

After playing around with different methods of applying pressure, I finally got something good:

PrinterCart-006

And a piece promptly flake off as I start blotting the workpiece dry. (the paper is dextrin coated, and releases after sitting in water a little bit, kinda like a water-slide decal).

After about 45 minutes in the ferric chloride (yeech!) etch tank, this is what I managed. Not acceptable, but at least I have an idea that the system works. Kinda. The etching is about 0.2mm deep. The design intent had been to sand to the black (raised) border, then fill the inside etched area with an ink, leaving the brass text raised against a black background. The piece would then be matted into a framed artwork along with the panorama being presented.

(For now, I’m just going to stick to my wax seal and signature, thank you very much.)

PrinterCart-007

(This is “R&D”. Failures are not unexpected; what’s important is documenting how things failed, and learning from it.)

[Fail] – Toner transfer for “photo”-etch

Thursday, January 14th, 2010

Well, no project always go 100% smoothly, and the important thing when one fails, is to document the failure.

Tried to use a toner-transfer method to do a photo-resist mask tonight, to chem-etch a brass face plate for a couple of pieces of photography that I’m framing up for presentation / sales. I’ve done this before in college doing DIY PCBs and earlier on in high school for model airplanes.

The process involves mirror-inverting a photo negative of the mask pattern and then printing it out on a photocopier. Because toner is a thermoplastic, a regular clothes iron can be used to remelt the toner and transfer it to another medium – balsa wood for cutting (this is before laser cutters) or, in my case, a sheet of brass plate from K&S Engineering in Chicago for a name plate.

Turns out I forgot that you need special paper. Toner sticks really well to regular paper (no surprise):

Blogged: http://www.TerenceTam.com

Oh, and it helps to turn the steam off on the clothes iron. :-)

I think this is the stuff that I used in college. I’m placing an order tomorrow for a small sample, shipped pony express (ground) from Florida. So, check back in a week to see how it went.

[Engineering] – More bullet sensor validation testing

Wednesday, January 13th, 2010

Tonight, I did more engineering validation testing of the IR breakbeam sensor mentioned in the previous article.

First, the setup. The sensor is securely mounted in my benchtop vise, with a phone book propped up behind the bullet path as a pellet trap. (Finally, a good use for those dead-tree edition phone books!). A regulated DC power supply is used to provide the power to the sensor module, and my oscilloscope is used to monitor the signal line. As before, we set the oscilloscope to trigger on a falling edge signal at a level close to DC Bus -.

Blogged at: http://www.TerenceTam.com
Blogged at: http://www.TerenceTam.com

(I need to get my garage sale O-Scope probes checked. They don’t seem to be reading the voltage right, but at least the signal generator test indicates a good test pattern. Probably something stupid I forgot to set in the software. I’m still learning how to use this thing).

Next, I set the oscilloscopes time scale to 100 nanoseconds per division. Yup, definitely picking something up! That’s a good sign. Rechecking at 1 microsecond per division shows a fairly clean signal.

Blogged at: http://www.TerenceTam.com
Blogged at: http://www.TerenceTam.com

To give Dad a good idea of what he’s engineering to, I need to take some measurements of the pulse width of the event. We’ve previously calculated about 18.3 microseconds for a round ball at 1000fps. (Note that we actually don’t know how fast the air rifle is shooting at, nor is the pellet perfectly round.)

Blogged at: http://www.TerenceTam.com

Look at that! 20 microseconds. Love it when the calculations matches real life data.

Blogged at: http://www.TerenceTam.com

The next shot clocked in at a mere 5 microsecond pulse. There could be 2 reasons: A) the angle of the flight path through the sensor might be changing, or I might be nicking the beam differently. Still, the oscilloscope clearly captures a 5ms pulse.

Blogged at: http://www.TerenceTam.com

Another shot, this time generating a 10ms pulse.

Blogged at: http://www.TerenceTam.com

Yet another 5ms pulse again – followed by a lot of electrical noise. That’s strange…

Blogged at: http://www.TerenceTam.com

Looks like the round nicked the sensor housing. Yeah, that would explain the sensor noise.

Remarkably the sensor still works. Putting the gun aside, I grabbed the soldering iron sponge and started dripping water past the IR beam. It registers on the O-Scope! (translation – this can be used for those awesome water-drop shots!)

Finally, here’s a couple of pellets recovered from the phone book. Love how you can see the rifling marks on the pellets :-) .

Blogged at: http://www.TerenceTam.com

[Pranks] – Difference between a cool job, and an AWESOME job

Tuesday, January 12th, 2010

You know what the difference between a cool job and an awesome job?

When you have a bunch of coworkers that relies on wit to prank each other. Better yet, when you can prank your boss, and he appreciates it.

Jared, the other Mechanical Engineer at my day job, also has a side business, building parts to soup up Evos. (Peeps, go over to his website, Binary Engineering, and give him some web love). Recently, to advertise his car, and his mad engineering skillz, Jared got a vinyl plotter.

Used to be that if you wanted a vinyl plotter, you were stuck with a Roland or Summa. These are the 800 lb gorillas in the vinyl plotter world – expensive, well crafted machines.

But if you think about it, a vinyl plotter is just an X-Y plotter with the ability to lift and lower a swiveling tungsten carbide blade. And the stepper motors and drivers required to drive such a system had come down drastically in price lately.

Enter the joys of Chinese manufacturing, stage left. Now, for < $400, one can buy a 24" wide vinyl plotter. The software's not as refined, and the cutter is a loud, cheap, affair - but it gets the job done.

And of course, what do creative engineers do given a new toy? They find a way to prank someone.

Here's a caricature of myself I found at my desk when I came in Monday morning:

IMG_9154

And here’s a new door decoration for my boss. He owns a Harley, so we have a feeling that this one’s gonna be up on his door for a while :-)

IMG_9158

:-)

[DIY] – Canon 580EXii repair

Friday, July 10th, 2009

Broken flash tubes are one of the most common ways a flashgun comes to an early demise. Unfortunately, the cost of professional repairs often make repairing a strobe a unfavorable proposition – at $150-200 minimum labor charge, often just for diagnostics alone, repairing a flash would costs about the same as buying a new one.  In this installment of the TwinGeeksPhoto.com blog, I’ll show you how I repaired my 580EXii flash gun so that Rachel can take two eTTL capable flashguns on her trip to the UK.

Before we proceed further, do understand that a standard hot-shoe powered flash gun contains high voltage components.  A 300mA jolt across a human heart is enough to induce fibrillation and cause the heart to stop, and the photo flash capacitor in a flash gun has more than enough juice to do this under the right conditions.  In other words:  THIS CAN KILL YOU. Perform these repairs at your own risk; we are not responsible if you kill yourself.

Years ago, when I was in primary school in Hong Kong, my Dad gave me an Olympus Stylus range finder to learn photography on.  It had an external clip on flash, powered off a single AA cell.  One day, after watching the Batman movie, I decided I wanted to build a bat signal, and a good way to do so would be to use the flash.  I correctly hypothesised  that the two recessed metal contacts on the side of the flash were used to trigger the flash, and also correctly deduced that shorting those two pins would cause the unit to fire.  When I proceeded to short them out, with 2 sewing needles pilfered from my Mom’s sewing kit, the flash fired – and sent me across the room.  I had made a potentially fatal mistake of holding one needle in each hand, and as such the electricity went through my chest.  The resultant chest compression was so severe that it (combined with the impact of hitting a hard wood floor) knocked the breath out of me.  Had that been a Metz potato masher, I might not be around today.

That little story out of the way:  let’s get started.

Parts needed:

Flash head:  The 580EXii’s flash head subassembly is integrated with the zoom motor and the high voltage ignition coils.  This makes repairs more expensive, but on the bright side, there is no high voltage soldering involved. The part # from Canon is CY2-4227,  and at the time of writing, US$63.23 from Canon Parts Service.  You can contact Canon Parts Service directly at: +1.732.521.7230.

Silicone oil:  The 580EXii is weather sealed.  This is accomplished by a special molded O-ring like gasket.  Over time, and after disassembly, this gasket material loses its sealing efficiency.  To get around that, I wet my fingers with medical-grade silicone oil and lightly oil the gasket on reassembly.

Medical grade silicone oil is often sold and marketed as “Water proof sex lubricant“.  And, yes, that’s really what I purchased it for – my bottle is quite a few years old and very much unused…

Tools:

Any well stocked DIY maker type should have the following tools:

*  Jewelers’ screwdriver set.  I highly recommend Wiha tools – they are German made out of Vanadium tool steel.  The set from my college days still works beautifully.  Local in Seattle, Hardwicks & Sons carries them.

* Optional:  A “spudger” – often an engineering plastic pry bar, for prying apart the plastic casing.  I actually don’t own one;  it’s next on my list (I’ve been making do with dental picks…).  You can buy them from iPhone / iPod repair stores, such as www.ifixit.com

Let’s get started:
IMPORTANT MESSAGE FROM OUR LEGAL DEPARTMENT:  THE PHOTOFLASH CAPACITOR IS CAPABLE OF HOLDING A POTENTIALLY LETHAL CHARGE FOR A LONG TIME.  AS IN, DAYS.  OPENING THE FLASH WILL EXPOSE YOU TO A SHOCK HAZARD.  YOU HAVE BEEN WARNED.  PROCEED AT YOUR OWN RISK.

There.  Now, take the jeweler’s screwdriver, and remove the screws shown.  For the screws hiding under the cosmetic santoprene trim plates, carefully remove the trim by inserting a screwdriver or spludger down along the edge of the trim piece, then gently prying it up.  The die-cut adhesive tape will lift out with the trim piece.

Next, with a flathead screwdriver, gently press down on the plastic spring clip on the swivel button side of the flash gun.  This unclips the two halves of the upper flash head enclosure.

Don't use excessive force!

Observe that there are 4 wire bundles coming into the flash head subassembly.  A larger ribbon cable carries the command signals as well as power to the zooming flash head, while a smaller, but much thicker gauge cable carries the actual lines for firing the flash.  THESE LINES ARE CONNECTED TO HIGH VOLTAGE AND CARE SHOULD BE TAKEN WHILE HANDLING THE UNIT.  At this stage, the voltage is probably ONLY 300V or so; it is enough to give you a very nasty shock.  Off the coils, however, the voltage can be in the kilovolt range, which will paralyse muscles.

HV and control cable bundling disconnected for clarity. Note the flex circuit ribbon entering the flexible printed circuitboard assembly for the flash head subassembly, about 9o'clock position to the copper coil. Do not damage the connector / ribbon cable!

Standard procedure, for anyone who’s ever worked with high voltage, is to discharge though a 1 megaohm resistor.  Most people don’t have a 1 megaohm resistor, so you can *carefully* short the contacts with a screwdriver with an insulating handle.  Sparks could fly when you do this, so be warned.  (In my case, I havn’t had batteries in this flash for over a year, so no fireworks.  Still, I shorted the pins just to be sure.

High Voltage cabling assembly.  Dont touch the solder ends without discharging the capacitors first.

Molex (tm) connectors for the high voltage cabling assembly. Don't touch the solder ends without discharging the capacitors first ... it hurts.

Next, disconnect the molex connectors.  A spludger works; I used a flat jeweler’s screwdriver to carefully pry them off.

The two other wires that are attaching the flash head are the following:  A small ribbon / flex circuit to the flash head’s flex PCA, and what appears to be a grounding, conductive plastic wire of some sort to the polycarbonate housing.  Remove these.  Remove any excess glue on the black grounding wire.  You will tape this back in place with scotch tape.  Pay attention not to pull too hard on the flex, those suckers are delicate.

Now, remove the 2 black screws holding the white polycarbonate housing.  The fresnel lenses will probably come out too.  Note the orientation and order of the fresnel lenses; the gasketed lens is in front with the ridges facing out.

This frees the flash head subassembly.  Replacement is in reverse order, for the most part.  Don’t touch the flash tube, or the output glass – oil on fingers tend to shorten lifespan of these components.  I found it easiest to tape in the black grounding wire, then the power and signal cable bundles, then install the subassembly into the housing with the two screws.  Finally, carefully hook the hole in the flex circuit connection with the end of a toothpick and slide the connection into the mating connector.

After the connectors are in, reinstall the fresnel lenses.  I use a little bit of waterproof sex lube silicone oil to lubricate the O-Rings, so that they maintain their weather sealing.

Reassemble in reverse order and test.  Voila!

[Artwork Presentation] – Framing Materials

Tuesday, June 30th, 2009

Things have been quite hectic with projects for me and Rachel, so this post is coming a bit late.  My apologies for the delay.  In this series of posts, I will go over how I print and frame, and why I decided to go this route, and the costs advantage of going the DIY route.   I’ll preface this post by identifying my target audience:  You’re considering printing and matting to save money and increase your profit margin from selling matted and framed art,  and you’re targetting the average consumer for your artwork.  Let’s be honest:  If you’re someone like Chase Jarvis, or if you’re fairly well booked wedding photographer, your time is probably more valuable taking pictures than trying to save a few bucks matting and framing your stuff.

Above is an example piece I did.  Cost of materials is about $55.00, plus the raw material cost of the print.  Print size is 12″ x 18″, printed using Canon dye-based ink on Canon Platinum Pro photo paper (A3+ size).  The framing profiles used  are Nielsen-Bainbridge #11 profiles in German Silver.  All mats are archival, acid-free mats – note that it is a double mat (with secondary border) around the photo.

Cost Analysis and Print Pricing:

One of the traditions that Rachel and I have is that we always try to visit a local farmer’s market every week.  Inevitably, there will be someone out there selling prints and artwork, and being photo geeks, we’d be drawn towards the booth like a furry little footrest going after a doggie biscuit.  And whenever I look another photographer’s work, I look at:

  • What they shoot
  • How they present their prints
  • What they charge

And lately, the prices have been falling.  I’ve seen framed artwork, about 6″ x 6″, go for as little as $40.00.  Another vendor at the Fremont Solstice market was selling 12″ x 36″ panos, framed, for $195.  And let’s face it, with the US entering what most people have termed the worst economic crisis since the Great Depression, discretionary spending is going to be down – way down.  Pretty objects to hang on walls certainly falls under discretion spending catagory.  Given what commercial frame shops charge – and let’s face it, they are good people trying to make a living in tough economic times too – it’s quite obvious that the only way these artists can be making money at these prices is by doing all the grunt work themselves, and hoping that increased volume will increase revenue.

In this post, we’ll go over the raw materials and cost data.  These prices are current as of Summer of 2009.  It’ll give you an idea of your “Cost of goods sold”.  You can then factor in your labor costs and know where your base-line pricing for your prints are.

Elements of a Framed Artwork

A framed artwork, for the purpose of our discussion, contains:

  • The print – what you’re displaying.
  • A frame.  Assumed to be a simple aluminum frame.
  • “Lites”, or the protective, transparent cover.  Either glass, or acrylic.
  • Mats.
  • Dressing for the frame – the hanger wires, etc.

The print:

We’ll cover our experiences with printing in separate posts – Rachel uses a Canon Pixma Pro 9000 series printer – which is a very good, desktop sized, A3+ (13″ x 19″) printer that uses a dye based ink.  Terence uses an Epson Stylus Pro 4000 wide-format printer that’s been rescued and lovingly restored.  It is a 17″ wide roll-feed capable machine (paper tray will feed ANSI C paper @ 17″ x 22″) that uses pigment based ink.

The general rule of thumb is that for 4″ x 6″s, Costco, Walmart, etc, all have very competitive pricing – pricing that home users can’t hope to touch.  However, bigger than 8″ x10″s home users will see a benifit.  Then there is also the instant gratification of being able to see a print right away…

The Frame

I chose to go with metal framing for a few reasons – I like the look of a good brushed, anodized piece of aluminum, and I *hate* gluing.  It is also relatively easy to assemble a metal frame – only simple hand tools are needed if you buy pre-cut extrusions.

The Neilsen-Bainbridge company have been in business for quite a while – and they have a line of aluminum framing extrusions.  Most commonly, you’ll find them in pre-cut kits from a well-stocked arts supply store.  I use Daniel Smith for my art supplies – and this is Neilsen-Bainbridge #11 profile, in precut form:

Note that it takes 2 kits to form a complete frame.  The lengths are the X and Y measurements on a frame – so if you need a frame that’s 22″ x 30″, buy the 22″ kit, and buy the 30″ kit.  The extrusions are cut approximately 1/8″ to 3/16″ over norminal, to allow for the thickness of the aluminum profile and tolerance for the mat and glass.  This typically is typically not a concern for most people, unless you’re setting up an assembly line and are trying to calculate packaging and shelving space requirements.

Each of the frame kits also comes with half of a frame hardware kit:

These are the angle brackets for assembling the frame, the spring clips, and the clip for securing the hanging wires.  If you purchased the framing extrusions pre-cut, the ends are already cut with a 45 degree miter and deburred for you:

See how clean the cuts are?  If you’re going the DIY route and cutting the extrusions from stock 10ft lengths, you’ll need a good power miter saw, or a good fine-teeth hacksaw in a guided miter box to achieve this.  Cutting a thin aluminum profile this cleanly is no easy feat.  You’ll need a fine teeth carbide blade optimized for non-ferrous materials – an 80 teeth 10″ blade, with cutting lubricant, would be a good starting point, plus a scarificial fence setup to support the material to prevent tear-through.  Note that a blade like that costs more than my first chopsaw I bought in college.  Below is a shot with the hardware kit installed and the frame fitted together:

A cost table for pre-cut extrusions can be found here.  The astute reader will note that the pricing of the extrusion goes up per linear inch the shorter the extrusions are.  The really obssessive number crunchers will make the assumption that the pricing follows a linear equation of price = 2a*x + y; where a = cost per linear inch, x is the length of each piece in inches and y is the fixed cost element of the pricing – the costs of the mounting hardware, the store’s profits, etc.  Using linear curve fitting, one can arrive at the cost model of 13 cents per inch for the extrusion and about $4.80 for the fixed cost.   The verification of these figures shall be left as an exercise to the reader :-) .

In an ever obsessive quest to “get a better price”, I started calling around to track down the wholesale distributor of these framing extrusions.  I found one place locally that carries it in 10 ft lengths.  Unfortunately they require a UBI number before they will sell you anything.  Price is $1.77 per foot – about 15c per inch, and a hardware kit costs $1.50.  Looking at the costing data above, this is a savings of, on average, of approximately $8.10 per frame, for cutting it yourself, vs buying pre-cut extrusions.  This does not include the wear and tear, and resharpening expense, of a carbide blade, the initial investment of a miter saw, plus the mess and headache of working with a miter saw and the clean-up time afterwards.  This is also assuming that I don’t have to buy and store additional scrap pieces, left over from cutting 10ft sections.  It is therefore my conclusion that unless I am doing a HUGE amount of framing, to standard sizes, it is not worth my time and effort to do the cuts myself.  (If I’m doing 10 – 20 frames at one time, then the analysis results would be different.  There, I can afford to setup a production stop guide, and at 10 frames, a savings of $81.00 might be worth it to lug out the saw, set it up and cut all my extrusions).

What if you don’t see a frame you like in the precut framing kit section?  You can order custom framing extrusions, cut to order, from the following vendors:

Daniel SmithPictureFrames.comAmericanFrame

Lites

In frame shop terminology, “Lites”, or glazing, refers to the glass or acrylic covering the artwork.  This serves to provide protection from the prints – in cases such as Ilford Smooth Pearl / Ilford Smooth Gloss paper, this is important for print archival as the porous microceramic coating on the paper is very susceptable to gas-fading.

In this department, the two most common, affordable choices are single strength window glass and acrylic.  Do not be tempted to use more shatter-resistant polycarbonate for framing – it may be more impact resistant, but it scratches a lot easier.

Glass can be purchased, cut to size, from the local Lowes.  Interestingly enough, Home Depot does not sell glass, cut to size, but Lowes does.  You buy from a pre-cut size and you get 2 cuts free.  Someone from the hardware department will operate the glass cutter for you.  Just remember that cut glass is really just broken glass with the break in a straight line – the edges are razor sharp and will draw blood at the slightest provocation.  In fact, most framing injuries occur with the sharp glass edge.  Make sure you wear leather work gloves when cleaning / handling glass.

Acrylic for framing comes in two grades:  plain, and reflection controlled.  Plain acrylic is just that – clear plastic.  Reflection controlled acrylic had been given a slight texture on one side to cut down on the amount of light reflected off the plastic’s surface.  When framed with an artwork close to the acrylic, this matt texture isn’t apparent, from normal viewing angles.  One can see the difference in the test shot below:

The glazing on the left is reflection controlled acrylic, the glazing on the right is plain window glass.  You’re seeing the glare from the overhead florescent lights in my garage in this shot.  Note that the reflection controlled stuff diffuses out the light evenly and improves somewhat the visibility of the text underneath.   Due to how reflection-controlled acrylic works, the print must be framed fairly close to the glazing.  Therefore, it’ll be very difficult to use this material with deep shadow boxes.

Reflection controlled acrylic is $5.45 per square foot from Tap Plastics, a local vendor, cut to size.  I started using glass, but have now switched over to this stuff, as it’s a lot safer to handle.  It comes with protective paper backing, so I don’t have to spend time cleaning it.  The drawback is that in the process of removing the paper backing, a lot of static electricity can be generated and the plastic becomes a dust magnet.  Still, this is nothing that a quick wipe with alcohol and lint-free wipe can’t fix.  As with any framing material, do not use ammonia-bearing cleaners, such as windex, to clean the glass /plastic, as degassing ammonia will greatly decrease the print’s life.  I’ve found that a mild detergent and distilled water / rubbing alcohol works quite well for cleaning.

One step up from reflection controlled acrylic would be anti-reflective glass.  This is glass that received an optical coating, by means of chemical vapor deposition.  Needless to say, this is very expensive, “museum grade” material.  Personally, if I ever need to frame stuff this way, I’ll go to the local frame shop.

In the next article, we’ll talk about the different types of mats, and the tools to work with them.  Stay tuned.

[Artwork Presentation] – How to save yourself $40.00 worth of grief and matboards.

Thursday, June 18th, 2009

For those who don’t know me, I should preface this post to say that I’m mostly a self-taught photographer, and recently started dabbling in print making and framing my work.  I’m a firm believer in experience being directly porportional to mistakes made – and by that metric, I should be pretty dang experienced.  I also try to not take things too seriously and laugh at my mistakes, and share them openly in hopes that others won’t repeat them.

That out of the way, let me show you what *not* to do on framing a piece of artwork:

Dont do this!

Don't do this!

The cuts are technically perfect – or pretty damn close.  There is some blade deflection in cutting the double bevel – something I’ll fix the next time by building an extension to the mat cutter.  But in the process of working out the border sizes – I had forgotten that I’m now framing things with a 3″ border instead of a 2″ border.  As such, I cut an almost perfect double-bevel opening 2″ too wide.  And if not for the fact that my cheap test ink-set in my Epson 4000 (the subject of another article) looks like mud – I’d be tempted to just re-crop the image in LightRoom and run a bigger print.  This was about 2, 3 hours of work down the drain.  (It took 2-3 hours because I was documenting as I go for this blog post – and screwed up the first go-around by cutting the bevels backwards.   In theory, I should be able to do this in an hour).

Now, that out of the way, let’s look at the framing tools.

First, the mat cutter.  Progressing up from a simple ruler / linear guide (such as Logan’s Adapt-a-Rule) system are board-mounted mat cutters.  They all feature some sort of adjustable fence system, with a base for the mat to be fed onto.  After playing with an Altos mat cutting system that my Dad owned, and the Logan mat cutters at Daniel Smith, I settled on the Logan Intermediate+ 450 model.

The 450 had a few BIG advantages over Dad’s Altos 4501:

  • Cuts on the line.  Logan’s design for all their cut heads (pictured below) is that the cutter head cuts on the edge of the guide.  To use it, you simply line up the cut line under the guide’s edge, hook the cut head onto the rail and go.  A U-shaped feature on the cut heads guide the cutter to prevent it from wandering.  This is a HUGE step up from the Altos design, which requires offsetting the guide from the cutline (much like a Skillsaw).
  • The 450+ cuts up to 40″ wide.  40″ is the “magic number” in framing.  Pre-cut metal frame strips comes in sizes up to 40″, and 32″ x 40″ is a standard size for matboards and foam board at any well-stocked crafts store.  It is possible to get matboard and frame extrusions larger than 40″, but I’d expect the cost to go up signifcantly, along with the transportation headache.  Besides, very few people have the wall space to hang a 40″+ piece of work, or files with the resolutions required to generate such pictures in the first place.
  • At about $160-170, this is a fairly affordable tool.  The next step up is about $350 and adds a longer squaring arm, which I can build myself.  This is a good price point for the features you get.

The Logan mat cutter comes with two cut heads:  a Model 702 Bevel cutter and a Model 701 straight cutter.  The names are fairly self-explanatory:  the Bevel Cutter cuts a 45 degree bevel for the mat openings, while the Straight Cutter cuts mats to size with a straight 90 degree down blade angle.

One other attractive thing about the Logan system is that their blades are widely available.  Michaels, and chances are most local arts store, will carry their replacement blades.  This is not true with the Altos system.  It pays to change blades often (each blade can only make about 10-20 cuts before losing its optimum sharpness) and so blade availability is a BIG deal.

The 701’s blade is fixed – retracting it requires unscrewing the mount screw and physically moving the blade.  It is however very rigid and will cut 4 ply mat board like butter.  Just be careful setting it down, so you don’t gouge up artwork, or ding the blade’s razor edge.

The 702’s blade pivots down into the matboard.  The silver line scribed onto the edge indicates where to start the cut – simply line it up with your reference mark, press the silver button to pin the cutter to the board, and push the handle down.  It’s pretty straightforward.

Not quite a framing tool, but invaluable nonetheless.  This is a Bessey Vario-Angle  strap clamp - used in carpentry and fine furniture making to hold pieces together while glue dries.  As with any tool, it pays to get a good tool and take care of it.  Retails for about $30.00.  If you’re local in Seattle, you can pick this up at Hardwicks, or Woodcraft.  Just don’t bother with Home Depot.

The purpose of this tool is two folds:  When assembling pre-cut metal frame extrusions, it allows all 4 members of the frame to be held in tension and aligned into correct position before the corner brackets are tightened down.  When building wood frames from molding strips, it applies even pressure on all four corners while the glue dries.

Harbor Freight makes a much cheaper alternative.  I personally have not used it, but I believe it will work.  As the Harbor Freight design uses a ratcheting mechanism instead of a screw and nut mechanism to apply the tension, I expect that there will be less granuality in applying clamping force and pressure.  I would consider the HF alternative if I were building multiple wood frames and need to setup the clamping for hours, but for metal framing work, I am quite happy with this little tool.

Rounding up the tool collection is a screwdriver to work the fastening clamps for the metal extrusions, as well as a marking pencil.  I use 4H pencil lead in a 2mm lead holder – this is the same tool that I started learning drafting with, some 20 years ago.   A 4H pencil lead can be honed razor sharp for really clean marking lines.  This particular lead holder has a sharpener built into the cap, which is good for obssessive-compulsive engineers sharpening their lead.

Now that we covered the tools – stay tuned for the next post as to how to mat and frame *correctly* :-)

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