Welcome to John's Blog World...

Welcome to my little sharing space--where I come to showcase some of my custom projects and to share "how-to" info with others out there. As a lifelong "maker", design enthusiast, and design professor, this blog explains some of the little projects I occasionally throw myself into, with the intent that I may help inspire others toward self-actualization and to show them how easy it really is to construct and realize their own ideas and dreams. As Brancusi said, "Create like a god, work like a slave."

Wednesday, October 16, 2013

If You Give a Designer a Helicopter Ride...

There is a popular children's book that I occasionally read to my kids entitled "If You Give a Mouse a Cookie..." in which a boy feeds a mouse a cookie, only to find out that the mouse keeps asking for more and more human-like privileges. People can be strangely similar to the mouse in this book, in that certain insights can help open their eyes to possibilities in the world around them. I have seen this many times as an educator; once students find out how easy something is to do, their inhibitions quickly melt away and they're able to feel more empowered to pursue their dreams. Several pivotal experiences from my own life have occurred this same way, as happened to me last month when my sweet wife secretly coordinated donations from several of my friends for me to take a "hands-on" helicopter flight to celebrate my 40th birthday (as seen here in this photo of me getting ready for the flight):

People who know me best know that I prefer hands-on experiences rather than simply floating around in the realm of theoretical and conceptual ideas (unlike many of the folks I often come across in American academia). On this helicopter flight (my first helicopter flight ever) the instructor let me actually take the controls, perform some basic maneuvers in the air, and practice hovering over the tarmac prior to the instructor-assisted landing. After having that quick glimpse into controlled flight, I had a greater and immediate appreciation for the skills acquired by pilots, and especially helicopter pilots! To say the least, the act of piloting a helicopter is one of the most multi-tasking--and exhilarating--vehicle control experiences I've ever experienced! And by doing it myself (with the appropriate instructor oversight, of course), I felt instantly driven to be able to do it again. But I also knew that it wouldn't suffice to simply fly in the sky myself. As a designer, I knew I'd HAVE to build my own aircraft someday, for sure. I'd tasted the cookie...now I wanted the milk to go with it.

Suddenly my mind was buzzing with possibilities that I never thought were likely to happen. I've always been interested in flight, and had even toyed with the idea of going into the Air Force when I was younger. But life situations and my own personal apprehensions (as irrational as they may have been) kept me from pursuing the possibility of flight. After this first flight, though, the door felt like it was wide open. And so was my sketchbook. I started using all the basic knowledge I had in my brain about rotor aircraft to inform some of my initial design ideations. Admittedly, it helped that I'd assisted some of my students last school year in designing some gyroplanes (or "autogyro" aircraft) through a sponsored project with the Spain-based Phenix Aviation...so I was relatively conversant about several of the benefits and constraints of rotor flight. I knew about the comparatively high degree of safety inherent in an aircraft that derives its lift through rotor autorotation (using a rotor that spins as it is propelled through the air rather than being powered itself--which is especially helpful to safely control the aircraft back to earth in the event of an engine failure), so I decided that a gyroplane was the direction I wanted to start exploring. I joined the EAA (Experimental Aircraft Association), hoping to get more involved with other local aircraft builders and hobbyists, and then "went to town" sketching some concepts. (I'll probably get involved with the PRA, as well, here in the near future.) Below are some turbo-quick-n-dirty "napkin" sketches that I used to get some of my initial ideas out of my head as fast as possible: 

For aerodynamic efficiency and for a couple other practical design reasons (like weight distribution within the aircraft), I opted to design a two-person gyroplane with tandem seating, placing the passenger's seat directly under the lift point of the rotor. Additionally, I opted to have the propeller situated in the front ("tractor" style) verses the rear ("pusher" style) for better flight dynamics. However, in order to accomplish this with optimal placement of the aircraft powerplant, the prop would need to be belt-driven by a driveshaft that would run between the legs of the passenger and pilot--adding a little more weight and complexity to the aircraft, but also adding better overall flyability. (To counteract torque effects on the aircraft, I figure it may also be advantageous to configure the drivetrain so the driveshaft counter-rotates in relation to the prop--which will most likely require gearing between the shaft and the prop.) After about a month's time, I filled up over half of my current sketchbook, and needed to get another one. A very small sample of the design thinking that I went through is evident in this cute little collage of work from that sketchbook:

Next, to wrap my 3D mind around some of the forms and mechanical systems that I was contemplating for this gyroplane design, I filled an afternoon creating a few computer models in SolidWorks. (Note the low level of detail in these, as I was just modeling different configurations of the gyroplane to explore its potential layout rather than to perfect its design):

The latter of these three quick models (shown above) is the layout that I'm leaning towards since tail-dragging aircraft tend to land a little more easily on the ol' runway. But I'll keep working through the details. The next step is to create some scale models and do some wind-tunnel testing with our aviation department on campus--hopefully without all the aviation guys laughing at me for designing a gyroplane in the first place. (I've found that a lot of fixed-wing pilots have a slightly negative view of gyros, for one reason or another). At any rate, a remote control model would then be in order, followed by additional development steps toward a full-scale prototype. Since I'm approaching this as a long-term project, I haven't developed any time frame for completion. I still have to get a pilot's license, fer cryin' out loud! But my plan is there...cookie and all.

Tuesday, May 21, 2013

My Uber-workbench

As I mentioned in a previous blog entry, I recently got my own shop space...but now I need to make that space more usable by adding work surfaces and storage. It's natural to want all new equipment when getting a new space, but my teacher's salary says, "no way." In an effort to equip the new space with at least my minimum shop needs (without breaking the budget), I've been searching for sweet deals on used equipment all over the place, but have come up short. I'll admit that part of the problem is that I've got some very specific needs, and I like my stuff to last. In general, the typical mass-manufactured, one-size-fits-all equipment that is made of cheap materials and reeks of planned obsolescence leaves me with a not-so-happy feeling. I really just hate wasting my time and money on things I know won't work well or work long. Huge economies have been built on the philosophy of "throw-away" goods, but broader wisdom dictates that such a manufacturing model is not very sustainable, and it definitely is not more cost-effective in the long run. Given those constraints, then, I decided to do what any other able-bodied, money-strapped design instructor would do: design my own equipment. (I should mention here that I really only have this option at my disposal because I have access to some amazing shop spaces at work, so I'm able to build many of the things I need on a more flexible time frame than someone who doesn't have such resources.)

So, today's blog entry will showcase my latest equipment build: my "uber" workbench. (By "uber", I mean that it was my intent to build a robust, stout, mobile workbench with built-in storage that had strength and longevity surpassing that of other mass-produced options available to me.) And since I like to constantly improve on my shop talents, I opted to build the base for this new workbench out of welded steel, simply so I can improve my TIG welding skills--which were lackluster at best. Yes, I could've simply made the whole workbench out of wood. And, yes, I could have opted for a simpler welding method, like oxyacetylene or MIG welding, but I already had those skills under my belt...and TIG was a bigger challenge that would come in handy with some other future projects that I had in mind. So TIG-welded steel with a wooden top it would be.

With my limited budget, I planned on making the top of the workbench as a butcher block glue-up made from scrap wood pieces that our students had left in the woodshop at the end of previous semesters. I've been stockpiling such scrap for a while and gathered together all the maple-species boards and pieces I could from the gleaned bounty. (Not only is this cheaper for me, but it is also "greener", since I'd be using wood that would have otherwise ended up in the landfill..."waste not, want not", baby!) After sizing up all the pieces on the table saw and chop saw, I laid everything out and found that I had just enough wood to make a top that measured 24" wide by 60" long and 2" thick. Obviously, it would've been too perfect to have scrap wood that was all a consistent 60" in length, but I figured that I could make do with the short pieces I had at my disposal. All I had to do was glue all the shorter pieces to an adjacent longer piece, and then take each of these glued-up pieces to the jointer to square them up. I could then glue up all the pieces into either of two halves of a large butcher block slab (since the full-width slab wouldn't fit through the planer after glue-up), ensuring that everything was even and square each step of the way. My plan worked perfectly, albeit over several long hours. It takes much longer to glue up dozens of small scrap pieces than it does to simply process full boards straight from the lumber yard. Here's a shot of the joints (gaps and all)...not the prettiest glue-up job, but it was free!

After the glue had dried overnight, I passed each half of the butcher-block glue up through the surface planer to get a nice flat top, then squared up the long edges on the jointer prior to gluing the two halves together. The final butcher block top was nice and solid, requiring only a little gap-filling with some fast-cure two-part epoxy where there was space between some of the scrap pieces.

A final coating with some Danish oil and wax finished up the surface perfectly. I could have followed this finish with a nice polyurethane coating, but I knew what kind of work I'd be doing on this workbench and did't want to worry about scratching up a really nice finish--the top just generally needed to be sealed and able to resist resin spills from my composites work. Here's the final top:

All told, the top of the workbench top took about eight hours to complete, mostly because of how much time was required to process the wood scrap that I used to build it. (By contrast, a butcher block top made from "new" boards would have taken about half the time to complete.) But the results were worthwhile, for sure, and the top was as stout as any workbench would ever need to be.

Next, I needed to build the base for the workbench. Although it would be overkill to build the design in CAD (verses simply sketching it up on a scrap of paper), I opted to use SolidWorks to create the workbench "virtually" before physically building anything. Since I know SolidWorks' software very well, it helped me knock out the design quickly and then easily figure out how much quantity of material I'd need before starting. The base would need to be built in multiple pieces for easy transport in my car (since I don't have a truck yet), so I modeled up the design for the base as a four piece construction that could be easily transported and assembled onsite.

I decided to construct the base from 16 gauge 2"x2" square tubing--material that was easily sourced from a local metal supplier. Admittedly, using this gauge of material would mean that my workbench would be severely over-engineered, but who wouldn't want a massive factor-of-safety when weight isn't critical and the cost difference is almost negligible? I've never been one to "hope" that my designs are strong enough; unless weight and optimized performance are critical, it's much more comforting for me to know that my projects can sustain a direct nuclear blast without being harmed.

Strangely enough, it seems like I always need a project like this to remind me of how easy it is to build something robust out of metal. Wood is fairly easy to work with in its own right, but there's always the material selection step that takes a while...at least to find the right color, grain, and character of wood. Plastics and composites fabrication have their own benefits, but they require a lot of planning and expense to build anything structural from them. Metal, on the other hand, has excellent material consistency, and structural projects can be fabricated very quickly with just a few tools (and skills). After a few quick cuts with the abrasive saw, I was ready to start my TIG welding adventure. I'd heard from lots of folks that there are some similarities between oxyacetylene welding and TIG...but it took me a little while to get a feel for those similarities. After experimenting a bit with the welder's settings and my own technique, I finally started feeling like I was getting the hang of it a couple hours into my practice. There's nothin' like wielding a welding device to make you feel like you're messing with the molten forces of creation.

To make the best use of my welding practice, though, I did most of my "warm-up" welds on the interior joints of the base where I knew most folks would never venture to look. Here's one of my practice welds...a little uneven and "chunky", but effective:

This same weld looked much better after a little work with the angle grinder:

It took me about five hours to finish all the welding and final grinding of the welds of the exterior surfaces and adjoining assemblies. The results looked a hair better than beginner quality, but pleasing, nonetheless. I am no way an expert with the TIG welder yet, but I'd definitely "cut my teeth" with that more advanced welding tool and am much less apprehensive about using it in the future--which was one of the main points of this exercise. Here are the main pieces for the workbench assembly ready for powder coating:

I finished up the surfaces of the base with a nice black powder coating, using our powder coating gun and huge shop oven. To do this, I cleaned off all the surfaces of my weldments with acetone, electrostatically applied the powder to the pieces and carefully transferred them to the oven. Half an hour at full temperature and they looked great...like something off a showroom floor!

I then drove all the pieces home, assembled them, attached the wheels, and the workbench was ready for use! It could still use a few shelves underneath (which I plan to add in the near future), but it is now ready for some good use, as you can see here in my garage...

At less than $200 for all the materials, this project proved to be cost effective (though I didn't factor in my own construction time, of course), as well, giving me some learning experience with the welder while producing a fine, nearly-indestructible workbench.

I plan on using my new, developing welding skills in just a little while on some automotive pieces that I'm currently designing...so I'll post those as well once I've got them completed. Keep rockin', my friends.

Monday, January 14, 2013

My DIY "Value-of-the-day"

As most people know, I'm big into doing things for myself. I was into "DIY" way before it was a cute little social movement. In fact, I think I was just born with one of those stubborn I-know-I-can-do-it-myself-so-let-me-do-it-and-don't-stand-in-my-way personalities. I'll be the first to admit, though, that it's not always cost-effective to do everything yourself. Modern mass-manufacturing techniques are able to make things very cheaply and with a generally higher level of quality and even instant "replaceability" than can be replicated by most folks. If you spend a great deal of your spare time building up experience learning how to make things on your own, you can narrow that gap between the cost of mass-manufactured goods and the cost of doing something yourself...even if it takes a few years to build up the level of skill needed to get things done with a decently respectable level of quality. 
One area where the DIY cost-effectiveness gap quickly closes, though, is in the area of repair services. If you've ever "snaked" your own drain or replaced a leaky faucet, I'm sure you've seen huge savings over paying a plumber to do that same job for you (although I've heard that plumbers do have some enviably long snakes for those big, nasty drain issues), even if you may get a couple scraped or bruised knuckles in the process. Doing your own auto repair has some very similar cost benefits, as well. But, just like any DIY activity, it requires some practice and often some specialized tools. Which brings me to my latest personal DIY triumph: learning a new skill, acquiring new tools, and feeling a sense of serious accomplishment by performing a much needed car repair that I'd never attempted before...as I'll explain in today's blog entry.
About a week and a half ago, my car failed its emissions test. I actually had figured that it would, since a bad oxygen sensor had triggered the "check engine" light a couple months previously. For those readers who aren't too savvy with the car stuff, simply speaking, it is the oxygen sensor's job, in part, to help tell the car's computer how much fuel it needs to allow into the engine...and when the oxygen sensor goes bad, the engine can run "too rich"--with too much gas--to the point that the catalytic converter (the part of the exhaust system that helps catalyze--or "burn"--unburnt fuel) can't keep up to the extent that it basically wears itself out. I knew this at the time the sensor warnings showed up, but kept putting off the repair until, well, the damage was already done. When my vehicle registration came due and it was my turn to take the car in for emissions testing, I pretty much knew what was coming: a new catalytic converter. 
I'd never replaced a catalytic converter on my own before, and assumed that I'd have to do some cutting and welding to do the job right. Feeling a bit overwhelmed by the task, I got a quote from a local repair shop. They said they'd need $1290 to replace the catalytic converter, the oxygen sensors (turns out I have two of them...one before the catalytic converter, and one after it along the exhaust system), and all the relevant gaskets and clamps. This quote sounded a bit high to me...probably because the quoted amount was equivalent to the cost of an entire engine rebuild when I was a teenager. (Granted, things have gone up in cost over the years, but I still tend to gauge auto repairs costs on what they were twenty-plus years prior. Silly me.) After doing some research, I found out that, in actuality, my car doesn't necessarily require any cutting and welding; luckily, I've got a bolt-together exhaust system, so it's a much easier job to tackle. At least "easier" to the extent that I could actually attempt the repair myself without having to enlist the high-cost welding skills of somebody in a muffler shop. There was, however, the possibility that the job may not go as smoothly as anticipated and that I'd run into some hitches along the way. But I've worked through several auto-repair snags in the past and have generally come through unscathed...aside from a couple of low-grade scars on my big ol' ape hands. And I figured that I may even have to get a couple of new tools to complete the job--which is always an added bonus. (Nearly every automotive tool I possess actually originated from a car fix-it job that I'd performed sometime in the past...so I've got a rather large and useful collection nowadays.) 
Next I'd need to find a day where I'd have huge chunk of time (and courage) to get the job done. Well, the state emissions folks gave me a ten day window in which to complete the repairs without having to pay the emissions testing fee again (which was only $25, but 25 bucks is 25 bucks, dude!), so I knew I couldn't be too slow about getting the job done. But, as luck would have it, there was a huge cold front and snow storm that blew into town the day before I was to perform the repair--which meant that my garage would be frigid (a balmy 20 degrees F on the OK' thermometer) and I'd surely have melting snow and "funky" stuff dripping on me the whole time I worked under the car on the repair. But you do what you've gotta do to get these kind of things done. Or, at least I do. (Other people just pay for the convenience of sittin' on their duffs while a certified auto repairman gets himself all goopy doing the job for them instead...which seems both lazy and cruel to me. Call me crazy for feeling so responsible for my own messes or even for experiencing so much sympathy for another person who would otherwise willingly charge me good money to do that kind of work.) Since the weather had taken such a turn for the worse, I knew I'd need a propane heater for the shop. So I added that little item to the list. And I'd probably have an exhaust bolt (or five) that wouldn't come off without some serious torquing, so I'd definitely need to add an impact wrench to the list...along with a couple impact wrench-worthy extensions to reach deep into the engine. And while I was at it, I figured I might as well change the air filter, spark plugs, spark plug wires, and even the oil at the same time. (These latter items can generally help with the emissions, as well, at least to a small extent...especially considering they were overdue for service, too.) Adding all these additional items took a bit out of the savings I would have seen by doing the repair myself, but I knew I was definitely going to get a lot more bang for my buck out of the experience. Just so you can visualize the difference in the cost/value of the repair that I was attempting (factoring out the "convenience" factor of having somebody do the work for me), here's what the original quote would have gotten me (note that the catalytic converter and gasket shown are actually the old ones I took out rather than the new shiny ones I put in)...it includes the catalytic converter assembly, a gasket, two oxygen sensors, and two exhaust clamps:

Now, here's what I got by doing the job myself (at a cost of $1293.77...only about 4 dollars more than the original quote from the local auto mechanic), including all the new tools and emissions-improving parts that I'd be leveraging to ensure that I would pass additional emissions inspections for at least a couple more years to come...(shown below are the same catalytic converter assembly, gasket, oxygen sensors, and exhaust clamps, but also the shop heater and propane tank, an impact wrench with extensions, plug wires, plugs, a plug wrench, oil filter and oil--only one of the five quarts of oil used is actually shown here--along with a new air filter)

To prove that I actually pulled off this little repair (aside from the grime that's stuck in the skin on my digits), here's a scan of the original "failed" emissions test (note the cool "void" watermarks that showed up from the original document after I scanned it...didn't know that would happen but the novelty of it made me smile nonetheless):

...and here's the "passing" emissions results, performed exactly ten days later (and on one of the coldest days of the year--which is even more impressive since the car's computer tends to make the engine burn a bit richer on cold days):

To say the least, I feel a huge sense of accomplishment for this repair. I learned how to replace my own catalytic converter, I now know where the oxygen sensors are located (and how to replace them), and I have new plugs, wires, air filter, oil filter, and clean oil. What's even more useful in the long run is that I can do this repair again if necessary, and without the dread or fear of what it may entail. Plus I've got a new heater for my shop, a new impact wrench, and some other tool accessories to help out with other future auto repairs--which I'm sure will come in their own due time.
DIY rocks. And it can be cost-effective too. But only if you've got the intestinal fortitude to give it a shot. Word.

Wednesday, December 26, 2012

Five Workshop Essentials

A short time ago our family "graduated" from a rather small living space into one that had an actual yard and, to my biggest excitement, a real garage. By "real", I mean a garage big enough to fit two cars, a workbench and several large free-standing tools while still having room to walk around. That means I'm now able to fulfill a personal need that I've been working around for about 25 years: my own shop space! Being a highly creative individual (at least as I’ve been called by many folks out there ), I've had to fill my innate needs to build things by borrowing space in other people's shops, garages, warehouses, and sheds ever since I was a teenager. As I can personally attest, this practice can get rather cumbersome, especially when you need access to the workspace at odd hours, or when your project requires borrowing others' tools, or when a project takes a long time to complete. All of these situations can occasionally strain the good will of those you're borrowing space from, regardless of how gracious or grateful you are about their generosity. Finally having the freedom (and responsibility) of your own creative domain can be quite liberating. At the very least, it feels like I've opened up an entirely new realm of design possibilities--albeit with the budget and time constraints that accompany it.
In designing the layout and use of my new space, I quickly noticed that I was relying on some "shop norms" that I'd consistently encountered over the years. These consisted of several aspects that I've found in successful shop environments that I've grown accustomed to in the past. Figuring that my "design rationale" for my new shop may be useful to others out there less experienced in shop environments, I decided to write about this particular topic in today's blog entry.

There are a wide range of considerations in developing your shop space, especially if you have particularly specific requirements for how you intend to use it. I'm going to focus on some of the more general shop needs, based on my own particular experience in fabricating projects made from woods, plastics, metals, composites, and a variety of other materials. Different materials require different tools (with some tools overlapping between some types of materials) and space needs, so a certain degree of customization may be required for your shop depending on what you're doing. Regardless of how you use your space, though, the following five essentials are bound to play a deciding role in how you'll need to develop the space. These essentials include making sure you have the following: adequate space, sufficient work surfaces, appropriate utilities, the right tools, and controllability of the work environment/atmosphere.

Essential #1: Space
First, let's talk about the need for adequate space. This may seem like a relatively foregone conclusion, but I've seen a lot of people try to make do with some incredibly constraining work spaces—often with very negative results. If you do have the ability to design the space you’ll be using, try to consider how much space you will reasonably need to match the size of both the projects and the tools you anticipate fitting into that space. This should include appropriate storage for materials and tools, and some good consideration for how to keep these organized and clean. Having adequate space means you have enough height, width and depth to easily move about and work safely. It's true that I've seen some very interesting projects come out of less-than elegant spaces, but in every one of those instances, there was always enough actual space to get the job done.

Entry/exit should allow for large projects so you can avoid the ship-in-a-bottle problem of finishing a project (where you can’t fit it through the door once it’s finished). At the very least, get some graph paper, make a plan view (top view) drawing of the space, and block out the area you’ll need for cabinets, shelves, workbenches, tables, tools, storage (for both projects and materials) or anything else that will go in the space. Be as thorough as you can with this step and measure out an existing room for a visual reference if you need to. If you find that you don’t have enough space to move around in your graphed-out space, then you may need to pare back the amount of “stuff” you plan to put in the shop—or you may, at least, need to find a way to creatively organize or securely stack everything so you can still work effectively and safely.

Essential #2: Work Surfaces
Another shop essential is an adequate amount of work surfaces. By “work surfaces”, I’m referring to horizontal surfaces and flat areas that can be used to place your projects and tools within arm’s reach as you work on them. While it is, indeed, possible to create things while sitting on the floor, our physiology lends itself to more effective project construction and tool control when we are either standing up or sitting at a table. Therefore, these usable work surfaces could include workbenches and tables, but may even consist of wide shelves, the top surfaces of cabinets (whether fixed or roll-about styles), or even an old door placed atop sawhorses. Optimally, it is best to use work surfaces that are adjustable or fixed at a comfortable working height. I personally prefer work surfaces that are set at a height of between 36 and 40 inches because they allow me to either stand or sit on a stool while working. I've found that standing works best when I’m putting a lot of physical force into a project while sitting works best for finer tool control.

Essential #3: Utilities
Next, don’t forget about the utilities you’ll need to make the workshop more useful. Some will argue that it’s possible to get some good projects done in an old, dusty, drafty, or leaky barn or tool shed. But, honestly, the quality of your work (and work experience) can be greatly enhanced when modern conveniences are included in the work space. At the top of that “modern conveniences” list is electricity. A simple electrical connection can make a huge difference in the capabilities of a work space. Even more can be done when surplus electrical capacity (beyond the bare minimum required to juice-up one tool or light at a time) is available in the shop space. I’ve been able to do a lot with a simple outdoor extension cord run all the way from the side of a house into a shed, but it’s always a hassle plugging and unplugging tools as needed from one socket. If you add (or hire a licensed electrician to add) a dedicated electrical line (and possibly a sub-panel) into a shop space, you’ve got a great recipe for increased shop success. Proper electrical capacity will allow for adequate lighting of the shop space, regardless of the weather or time of day. It will also help handle the electrical needs of power equipment you'll be using. Having a compressed air supply can be especially helpful, but it won’t happen without electricity (unless you’ve got one of those handy, though somewhat-rare, gas-powered compressors). Remember that if you intend to expand your repertoire of power tools over time, it may be useful to increase your electrical capacity with a dedicated electrical panel, as well. Repeatedly blowing fuses in the middle of a tricky operation with a power tool can be both annoying and dangerous.

Depending on your shop needs, a utility supply of water and sewer drainage (for shop or project cleanup) or other amenities may also be important. In the case of my shop, where I’ll inevitably be doing some composites work, dedicated vacuum lines are also a must, and can be piped through sealed PVC or steel pipes connected to a vacuum pump that is electrically driven from elsewhere in the shop.

Essential #4: Tools
Additionally, no shop would really even be useful as a shop without tools. Tools are one of those things that set us apart from our four legged friends, so it would be difficult to overrate their usefulness in a workshop. With the right tools (or compensatory skill and ingenuity) just about any operation can be done in a workshop. One very formidable problem that many builders run into, though, is the cost of those tools. Before starting out on any project, always take inventory of what tools will be needed, and what tools you’ve actually got or what tools you can creatively use or modify to get the job done. In building a collection of tools for proper shop work, I’ve seen many a craftsman fret more than their share about having practically every tool possible. However, a bit of ingenuity can compensate for a lack of expensive or "amazing" tools—in spite of what the tool marketers will tell you. For example, I can do some things with a cheap bandsaw that many of my students think can only be done with an expensive CNC router—it just took a bit of practice to get to that point. In building up an appropriate collection of tools, remember to also include clean-up tools, like brooms, whisks, dustpans, trash cans, buckets, scrub brushes, towels, etc.

Essential #5: Environmental Control
Lastly, consider what amount of environmental control is needed for your work space. This particular aspect of a shop refers to how comfortable the space is to work in, since the comfort level of the environment can actually affect a craftsman's effectiveness. For example, it may be important to include climate control for the purpose of personal comfort (too cold or too hot are both dangerous), safety (sound noise levels, poor ventilation, and slippery floors can be hazardous in their own rights), but also for reasons that may affect the quality of the projects being produced in the shop environment (such as when heat-sensitive chemical processes are being employed, as with resins used in composites or paint applied to a project).

For some people, an important environmental concern is the music that is floating through the air of the shop. For me, music is an extremely important environmental element that can directly affect how well I can focus my work efforts in the shop. I've gotta have shop tunes. I was raised on "shop rock", listening to 80's hair bands and 70's classic arena rock, admittedly, mostly for its ability to channel my youthful fits of testosterone-borne funk into more useful energy within the shop. But these days I'm just as amenable to other less raucous music, as long as it fits my mood and helps direct my concentration to the task at hand rather than distract from it. I even have a special set of playlists on the handy MP3 player set up for my shop mood-of-the-day (which beats digging out all the ol’ cassette tapes to get my fix of Asia or Boston tunes).

So, there you have it: five (lengthy) essentials for a workshop environment. Many craftsman out there may view this entry as a very boring recap or what they already know about shop spaces. But hopefully it is still useful for anyone who is looking to design (or redesign) a work space for best work efficiency and project quality. 

Keep rockin’ and building, my friends!

Thursday, November 15, 2012

Building A Carbon Fiber Splitter For A Mitsubishi Evo

One of the benefits of being a university professor is that I get to be involved in interesting projects outside the classroom all the time (at least when my hectic work schedule will allow for it). Many of the projects I get to dabble in come about because of my connection with students from class. So when one of my past students, Josh McGuckin (of Camera Courage fame), told me that his friend needed some help with his race car, my interest was immediately piqued. I have a hard time saying "no" to car projects--for better or for worse. In this particular instance, Josh's friend, Dave Kern, needed a new splitter for the front of his highly modified Mitsubishi Evo that he would be racing up Pike's Peak during the summer. His old splitter had been damaged when he hadn't been able to adequately negotiate a high-speed turn during a race the previous year, and he wanted something a bit thinner, lighter, and stronger to replace his old, mangled part. After looking at the way the original one was built, I figured a rebuild of this part wouldn't be a hard task to pull off; the old splitter was basically constructed as a low-cost/low-performance composite sandwich construction with a single skin of carbon composite over either side of a plywood and a open-celled polypropylene core. It was plenty heavy and lacked the stiffness that is really necessary to make an effective aerodynamic control surface. I knew I could make a splitter with significantly more stiffness than the original part, and even include all of the custom features he needed for the shaping and performance of his particular car. So, I said yes to the design challenge...and this blog entry will give the quick-n-dirty low-down of how I made the part. (Readers will note that some of the build details have been left out of this "how-to". The reason for this is that I am held under certain contractual non-compete constraints because of the books I have written on composites; I simply can't duplicate/publish those things I've previously written about for my publisher. For more info on the details specifically related to techniques shown in this build, though, check out my book Composites Fabrication Handbook #2.)

I first started out with a cardboard mockup of the part. I cut and taped some corrugated cardboard to make a representative piece that fit under the actual car as closely as possible. It included references for all the body lines and connection points to the frame, as well as the shape of the ducts that would direct airflow around brakes (as shown below). This mockup process took about 3 hours, but this included consultation and drive time to the shop where the car was, so the build of the mockup itself was actually very quick:

After examining the existing part and the bottom of Dave's car, I could tell that the trickiest part of creating this splitter would be fabricating the ducts, since the rest of the part was completely flat on the bottom. Flat parts are simple to fabricate in composites because flat sheet metal or plastic can be used to make a mold for the part with relative ease. More complexly shaped parts usually require much more planning in the mold-making stage. One of the easiest ways to fabricate a section of the mold for something like these ducts is to cut out wood and then simply cover it in formed sheet metal. These pieces can then be attached to a sheet of acrylic plastic which acts as a base for the mold. (For this mold, I opted for 3/16" thick acrylic that would be fastened over plywood because it is already very smooth and easy to polish and wax...plus I figured it would be easier to shape into other future mold components after using it for this project. Acrylic is not recommended for molds where polyester or vinylester resins will be used...the styrene in these resins will actually attack the acrylic!) I stacked up some scrap pieces of plywood and MDF (making sure to get just enough height in the stack for the needed dimensions of the duct) and used wood glue to join them all together. Next, I cut the stacked wood pieces on a table saw in successive passes, raising the height of the saw blade with each cut as needed until I was able to complete the contour needed for the top of the duct. I followed this cutting step with some sanding using a large spindle sander to smooth out the rough steps in the surface of the wood piece. I then cut the sides of the duct with a bandsaw and sanded it to a smooth final shape. Here is a side view of one of the pieces...

...and here is the top view of the same piece (shown below). It wasn't pretty, but it worked like a charm!

To create a quick, non-porous, mold-ready surface, I cut some 24 gauge steel sheet with some shears (dressing out the edges with a file) and shaped it to fit over the wood piece:

I then covered the edges of the sheet metal and wood with the type of aluminum tape that is made for HVAC repairs (as shown below). This is a quick and effective way to get the edges completely sealed prior to molding over the form.

I should probably explain here that it was necessary to make a solid wood support under the sheet metal because the composite layup was to be vacuum-bagged over these mold components; even ambient air pressure would have crushed a hollow sheet metal construction like an empty pop can under a Mack truck, so support underneath this feature was critical. 

I used drywall screws to attach the acrylic sheet to a sheet of construction grade OSB (for added rigidity). When fastening acrylic to anything, always make sure to first create clearance-holes for the screws; acrylic cracks very easily under stress, so driving screws through an improperly sized hole in acrylic will quickly fracture it. I then adhered the duct forms to the acrylic base using double-sided mastic tape, and then sealed the edges of the forms to the base with modeling clay. Note that a couple areas of the modeling clay had been strategically removed at the edges of the duct forms to accommodate flat areas on the part where hardware would be used to mount the splitter to the car (as shown below). Fabrication of this mold for the splitter took only about 4 hours. 

After a nice, generous waxing (which took about 2 hours), I performed the layup: one ply of plain-weave 3K carbon fabric topped with a ply of +/- 45 stitched unidirectional (non-woven) cloth for enhanced torsional strength. These were both wetted out in succession using epoxy resin and a squeegee:

I added a layer of peel ply fabric and then applied a vacuum bag over the part and allowed the resin to fully cure (overnight):

After cure, I removed the bagging materials, inspected the part...

...and prepped the surface for the rest of the layup by carefully grinding down any resin wrinkles left on the surface of the part by the bagging materials:

Next, I used some craft paper to make patterns for the core materials that I planned to include in the second half of the layup. Since the part was symmetrical, I only needed to make half of the patterns and then double up on the cuts from the core material stock.

I marked and cut out the PVC foam core material based on the shapes of the patterns, paying close attention to  the placement of the patterns so I could use the core material as wisely as possible (because it ain't cheap):

I then "dry-fit" them over the lower half of the splitter that I'd previously formed. I beveled the outer edges of the core and scored the bottom side of the core pieces that would be placed over the curved faces of the ducts (since scoring the foam core helps it better conform to curved surfaces):

Next, I used epoxy filler to tack down and gap-fill the core to the bottom half of the splitter (as shown below). Baltic birch plywood worked well as an effective, lightweight compression resistant core in the areas where mounting hardware would be later used to bolt the splitter to the car:

I then laid up the second half of the composite sandwich (which was a reverse of the previous layup) and bagged the part like before (see the photo below). Layup of both sides of the part and prep of the PVC foam core took about 16 hours.

I then removed all the bagging materials from the part to reveal the nicely consolidated composite beneath:

Here is a view of the cured part, straight out of the vacuum bag:

I demolded the part to reveal its smooth, mold-facing bottom side...

...and then used a scraper to remove the modeling clay (as shown). A little naphtha and a rag cleans up any left over residue quite well. 

I then used the original cardboard pattern and an abrasive cut-off wheel on a rotary air tool to trim the edges of the part. (Note that the photo below shows the location of the mounting hardware, drawn onto the top of the part using a silver-ink Sharpie marker. These marks helped in aligning the part to the mounting locations on the frame.)

Here's a photo of the completely trimmed part, ready for final holes to be drilled for mounting to the car. Final demolding, part cleanup and trimming took about 4 hours.

The final part was significantly stiffer, thinner, and lighter than the original. After about 26 hours of work, the new splitter was ready for the race! Here's a little photo of the finished car peeling around the turns up Pike's Peak (notice the flames coming from the exhaust in the front!) with the new splitter mounted just below the front bumper:

With this little baby mounted to his car, Dave ended up getting second place in his class and fourth place overall. Not bad for any Pike's Peak racing machine! Maybe I can further help him get a first-place winning vehicle all dialed in for next year...if my day job doesn't kill me first.

As demonstrated here, high quality parts can still be fabricated in composites using relatively inexpensive mold materials and techniques. All that's needed is a little ingenuity and know-how (both of which come with practice). Now go build something for yourself!

My "Woobie"--The Comfort of a Sketchbook

Those of us who were raised in the 80's (or even those of you who otherwise experienced that wondrous decade after the fact) may remember the term "woobie", which (as far as I can tell) originated from the now-classic film "Mr. Mom". In the movie, Michael Keaton's young son has a very sentimental attachment to a blanket that he calls his "woobie". His son takes this blanket everywhere he goes and clings to it because of the emotional comfort it provides him. While I admittedly had a special teddy bear (home-made by my loving mommy) that had some similar woobie-like qualities for me as a shy little boy, I recently realized that I have a current, less obvious woobie that I frequently feel lost without: my sketchbookIt is something that I constantly have with me, constantly holding on to, and constantly using. Because of how much I’ve used my sketchbooks through the years, it gives me a certain degree of comfort having one close by. So, in today’s blog entry, I’ll try to explain my affinity to the sketchbook and how it may be of benefit to others to keep one as well. (Here's what my current sketchbook looks like...unassuming on the outside, but full of my "ponderous" sketches...)

I was exposed to the idea of recording my ideas at a very young age. My grandfather, who was a high school teacher, could tell that I was an inventive child, and he lovingly encouraged me to write my ideas down in a notebook. He taught me that it would be best for me to carry my notebook with me at all times so I could write down my inspirations as soon as they came. As a result of his encouragement, I recall making my own small notebook out of paper and staples, with a cardboard sleeve that would fit over it so that I could carry it in my pocket without worrying about bending up the pages. The notebook filled up very quickly because I ended up making a flip book animation with it called the "Omega Robots" in which two Transformer-like robots battled it out to an explosive end. It probably wasn't what my grandfather had in mind, but his encouragement to record my ideas planted a very important seed. I went through (and lost) many small notebooks when I was younger, but by the time I was in high school, I started keeping a full-size sketchbook and regularly sketching in earnest. As a freshman in high school, my art teacher (wisely) required us to routinely draw in our sketchbooks, regardless of the subject matter, to help us build our skills. If I could go back and talk to my gramps and that art teacher of mine, I'd thank them in the most grateful way possible, because the simple act of regularly drawing my ideas (rather than just writing them down) is what has helped form an important habit of design conceptualization and development that has turned my design skills into what they are today. From the standpoint of my professional work as a designer, my sketchbook "habit" has helped forge an important pattern of design documentation--something that has been especially important with projects requiring thorough documentation for competition, intellectual property, patent, and regulatory reasons. At latest count, I have over twenty five sketchbooks (that I can still find!) that document my thoughts and ideas sketched over a period of more than twenty years. Here’s what a small handful of those sketchbooks look like:

There are a variety of reasons why people keep a sketchbook. Some of these are discussed in a ThinkSketch by Paula Briggs of AccessArt--which is a nice little reference I found after I’d already written most of this blog. (Interestingly, much of this book's content aligned very well with my own reasoning for the usefulness of sketchbooks.) Similarly, I have a few personal and also pragmatic reasons for consistently keeping a sketchbook over the years. For one, sketching helps me work through my ideas--of which I probably have more than my share. Sketching (just like writing) is a sort of mental solidification process for ideas. It helps me take an amorphous thought from its original, ethereal state into something more gelled and tangible. With additional directed thought and sketch development, that simple idea will then solidify into a concrete, well thought out, concept ready for further physical testing and product development. It's as though sketching allows me to gather my bits of mental dust, use my pen to stick then together into a loose, muddy paste, and then carve them through more mental refinement into a well-defined conceptual sculpture that can then be fired in the kiln of physical modeling and testing. For example, here's a shot of a carbon fiber side mirror I created for a concept car that I'm working on, and the sketches from which that design was formed, designed, and fabricated:

I believe that sketching also helps me to communicate my ideas with others through visual means. Humans learn to speak by actually talking--by making mistakes, finding the proper pronunciation and grammatical structure in round after round of vocalized trial and error until effective communication is achieved. Likewise, a musical instrument is learned by practicing the proper muscle coordination and mental construction and deconstruction of notes, rhythm and harmony until real music is possible. These each take time and untold hours of practice. And sketching is no different.  Regardless of how many how-to books you read, how many sketchbooks you study, or how many video tutorials you view, it is still the act of practice that makes the sketches, and their ability to effectively communicate, better. (Here's a relatively recent sketch of some bike frames...with a little marker added for better readability...)

With sketching, I feel that I get to share my unseen thoughts with others in a way that helps me better connect my ideas with them through visual communication. Words can only express so much, and sketches are their own type of language. Sketches  requires some communicative refinement and style to avoid cognitive dissonance between the designer and viewer of the sketch. But pictures have their limitations, too...which is why I find that annotation is so important in design sketching. Art sketching tends to be very expressive and "free" in nature, leaving itself open to interpretation of the artist's intentions. Design sketching, on the other hand, requires a certain degree of responsibility to the needs of the viewer to correctly explain the intentions of the contents of the sketch. For example, here's a sketchbook entry I drew of a visitors' site in Japan during a work visit I made there several years ago...simply for artistic reasons:

By contrast, here's a sketchbook entry showing some of my design thinking on the form and ergonomics of a new digital SLR camera:

To a certain extent, the mental process of design problem solving is illuminated through the flow of ideas that are revealed through the sketchbook. I have to admit that this area, in particular, is of keen interest to me as a design instructor who is constantly called on to explain those mental processes to students. (Admittedly, it is probably this later focus of mine, and my natural tendency to try and explain complex processes, that has made my three books on composites so successful among composites enthusiasts.) Here's a view of some of the process thinking that is going into my current concept car project:

While my sketchbooks show my design focus, the iterative processes that I go through, and even my understanding of a given problem as my experience in that subject develops over time, they also provide an enlightening chronological record of my ideas as they develop and mature. This is especially evident through the level of quality and complexity that my sketches have shown over the years. Some interesting growth is apparent here between a sketch I did in high school in the late 80's ("Then..."), and one I did earlier this Spring of 2012 ("Now..."):

To a certain extent, my sketchbooks are even a self-affirmation outlet that helps me feel that my thoughts and skills are worthwhile and incrementally developing the more I sketch. They show a personal record of my thoughts--and the variety of thinking that goes on in my head. In one way, my sketchbooks were my private, low-tech blog-space before I ever decided to send out my written and photographic ideas through cyberspace in this public blog. They even help me express my (often suppressed) inner engineer...which is why I like exploded views so much:

Although I have become accustomed to certain sketchbook norms, such as drawing on white, smooth paper with ballpoint pen (because of its permanence and lineweight versatility), I am constantly on the lookout for another good sketchbook. I can't go into a bookstore without going to the journal section in search of an unruled sketchbook (since lines are too confining to my sketch processes) that could be my next design record keeper. I'm always looking for just the right paper (smooth and thick, yet flexible, bond feel best to me), with the right binding (something that allows the covers to lay flat or fold over is best), and even the right size (big enough to rest my big monkey hands on, but small enough for easy, unobtrusive transport). As you can see from this "wad" of sketchbooks in my office, I tend to prefer coil-bound sketchbooks (again, because they lay flat and the cover can be bent back during sketching...which tends to be more comfortable when sketching on your lap):

I am constantly looking for a better sketchbook outlet that will help me express my ideas even better...at least until technology makes it possible to perform direct mental downloads of my ideas (which would be sweeeeeet!). I've even looked for good digital sketchbooks over the years, and have tried several Wacom Cintiq, Intuos, and Inkling models, as well as spent considerable time sketching on apps using Apple's iPod and iPad and a variety of other touchscreen tablet interfaces. They all have some benefits in the range of image manipulation, color, and output formats that are available, but I always come back to paper. There are still some significant limitations in both the hardware interfaces and the software packages that help the designer draw, especially if you've got a significant number of "legacy" neural connections fused through several years of successful hand-sketching techniques on paper. Digital sketching interfaces are increasingly important in design, but pen and paper sketching still have their own substantial merits.

A few times now I've been asked by my students to make copies or to publish parts of my sketchbooks for them to have. At some future date, I may actually go through the hassle of publishing some of my sketched works and random designs...if it seems that would actually be worthwhile as a learning tool for others. But we'll see. Until then, I'll just keep sketchin'.