Quick thought on the porta-band stand described in an earlier post, mounting the saw to the vice-mount takes a couple of minutes. You could make a smaller custom foot that always stays on the saw and “dovetails” into the vice mount. A single machine screw could be used to secure the small foot to the mount. This way the saw could go from case to vice (and back again) in under 30 seconds.

Ian made this custom foot for the Porta-band that clamps into the vice this past week. Its 3/8” cold roll plate with a bit of scrap 1x box tube welded to the underside. A spring clamp on the trigger acts as a low tech on/off switch.
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There’s a great instructable on how to TIG weld on the loose. Those who’ve already mastered any other welding process will probably enjoy it. While you’re at it, check out Cheap Welding for Punks.

I love coffee. I also love levels. What would be better than a coffee-mug level? The LevelMug® is the perfect mutli-tool intended for spot checking scenery & frustrating your carpenters between production meetings. Once filled with coffee or tea LevelMug®’s proprietary precision ground MugMarks® allow you to quickly estimate level to within 2.5 degrees.

Note: Only use the LevelMug® in the vertical and horizontal planes. Especially when it’s filled with hot coffee. You know, like that time you dropped by the MacDonalds drive thru for a quick cup of joe. You won’t put that in your lap again, will you?

I’m sending in the patent application this very moment.

Just a few random thoughts on the tail end of a turkey weekend.

Do you design & engineer solutions whilst drafting? Consider planning out your projects more before you sit down at the computer or drafting table. It seems that most people just dive right in. Oh sure, there’s budgeting and scheduling (and hopefully element lists) that will help define the project and help you to focus on the various bits and pieces. But you can save a bit of grief later on by further subdividing your project. Note that I am speaking more about the construction and engineering involved in a project. Consider breaking the project it into chunks.

Chunk management 101:

Reduce the total number of dependancies between chunks. How can these chunks be delimited so that they are as independent of each other as possible?

Flexibility is the key. When you have to make changes a week into drafting, you will be glad when the changes don’t weasel a finger into every aspect of your project, causing a steaming pile of dreaded revision hell.

Intelligent chunking allows you to manage changes and revisions more accurately and in less time.

Look at the timeline. Which chunk will be engineered first? What chunks get built first? Which chunks depend on other chunks?

Record your chunks. Write them out on a cocktail napkin, draw pretty charts, keep a page in your diary. However you approach your chunks, write them down somewhere. The main thing is this: keep a sense of perspective concerning the chunks vs the whole project. Look for the connections, the shortcuts, the interferences.

Just remember, too much project management makes the baby go blind.

While in grad school I became a fan of what I like to call Past & Punch Templates. When you need to fabricate a part that is particularly funky or needs to be exceedingly precise, you print a full sized drawing from CAD and past it onto the material that needs to be machined. Fairly simple right?

For years I’ve used spray 77 to adhere the template to the part, but then you have to deal with removing the adhesive from the part when it is going to be painted or moves against another part. A step I feel too lazy to take at times.

Last week I got to thinking how ideal Post-it glue would be for this kind of work. Post-its don’t mar other surfaces, and it is a hell of a lot less hazardous than spray 77. If only they sold the glue without the Post-It. Well they do (kinda, see here). You can find the adhesive at Amazon. It comes as a glue-stick that couldn’t be easier to apply (added bonus: it brings back memories of kindergarden.)

Perhaps this could be used to afix routing templates as well. I haven’t tried it yet, but it sounds good in theory. I’m ordering a stick this weekend and I’ll let you know how it goes. So as to not sound like a 3M shill, you can also Google “repositionable adhesive” to look for similar products.

Fun links:
Electron microscope image of Post-It glue.
Wiki link on Post-it notes.
Re-stickable Glue Stick MSDS

Dirt on stage. Poo poo. Dusty, dirty, a real pain in the ass. Jen tells me that she’s got a way to tame the dust. The secret is glycerol (aka glycerine or glycerin). Don’t worry, glycerol may sound threatening, but rest assured, it is not. It is a sugar alcohol that is found in everything from food to pharmaceuticals. Obligatory wiki link to glycerol. You can buy glycerol in 5 gallon buckets, which should last most folks for an entire run.

Before each show spray the dirt with a mixture of glycerol and water. The mixture will wet the dirt enough to prevent dust without getting muddy. The mixture will also keep the dirt damp for longer than just plain water. Sweet. Jen pointed out a few things:

• She didn’t remember the exact mixture of glycerol to water that she used, but her results will assuredly vary from yours; experimentation is the key. (I suggest you try a 1:1 first & see where that takes you.)
• The dirt will darken (you know, like it does when wet) after application. Experiment with the amount of mixture applied until you find the correct hue (failure to do this may lead to cranky designers)
• The mixture will slowly evaporate out of the dirt during the show. Experiment with mixture ratios, and time of application (before curtain.) If it just doesn’t last long enough, you may have to increase the amount you are using.
• Put on your scientific caps; remember that things like stage lighting, air handling and temperature will affect the whole shebang. Be rigorous & meticulous whilst experimenting.
• And above all else, after you find that perfect mix - be consistent!

Thanks be to Jen, who is a Stage Supervisor goddess.

Good news everybody! I’ve finally posted movies of the flicker candles in action. You can find them here. Jeez, that took long enough.

(Or: How I Stopped Worrying and Learned to Love the Command Alias)

If you are an avid AutoCAD user, you know that setting up your command aliases is key. For those interested, I’ve put my customized portion of the acad.pgp file here.

For those of you who are not familiar with AutoCAD’s command aliases, you’re in for a treat. Every time you enter “rec” instead of “rectangle,” or “l” instead of “line” you are using a command alias. Te best part is that you can customize your aliases to your heart’s content.

Customizing your aliases provides a number of advantages. Brief bullet list:

• Edit the shortcuts so that they make sense to you, not some guy at Autodesk.
• Edit the shortcuts so that groups of commands are related.
• Cut down on the overall number of keystrokes your numb little fingers enter during the day.
• Select your most frequently used commands and try to reduce them to as few keystrokes as possible, even if other less frequently used commands have to be reassigned to have longer aliases.

Read More...

Update for “Pivot Puck” post. -- We installed the pivoting masking wall today, and it was a smashing success. Pivot pucks are definitely going into our stock inventory.

We need to pivot a few masking walls for our upcoming production of Hughie. So this little UHMW bugger was born; I like to call it a pivot puck. Screw the puck to a surface and place a shaft in it (our shaft is welded to plate steel that bears on the top surface of the puck) and you’ve got an instant pivot point! (Just make sure the screw heads are countersunk below the surface.) It’s so sexy that it may become a regular stock item in our inventory. I will post an update after we use them for the show.

Continuing in the pivoting vein, these are the pivot points we are using for the top of the masking walls I mentioned above. If you haven’t seen the half cheesebouroughs before, they are hard to beat when attaching stuff to pipe.
edit: Oh yeah, you can find them at BMI.

The Lazy Drafter. I stumbled across this site a few days ago. As I am a lazy drafter myself, I’m already a big fan. If you work in AutoCAD, consider it recommended reading.

For those who enjoyed the post on imperial & Metric Conversions, I’ll recommend this post (Automatic Scaling...), it compliments mine nicely.

I’ve thrown a few of my most frequently used LISP routines on here. You’ll find the files & descriptions here or in the sidebar. I will be adding more as I clean them up and determine where I acquired them (so I can give credit where credit is due.) I am also tinkering with the idea of posting my pgp file; while not especially useful, I am always interested to see what shortcuts other people use. Perhaps someone out there feels the same way. I’ll think about that while you root around in the LISPs directory.

Yesterday a friend asked me how to convert an AutoCAD drawing from metric to imperial. He needed to dimension in inches and draw imperial sized objects inside a metric drawing. Turns out the Autocad help is not so helpful on this specific subject.

Units & Units:
So here's the deal, AutoCAD “thinks” in a drawing units. These drawing units don’t have a real world size. The only relation to real world size they have is the name that we assign to them in the units dialogue box. But a name doesn’t mean a thing to AutoCAD. 1 metric drawing unit = 1 imperial drawing unit = 1 mile drawing unit.

Example: when you copy & paste a 12"x12" rectangle into any drawing, AutoCAD really pastes a 12 unit x 12 unit rectangle. If you paste that same 12”x12” rectangle into a millimeter based drawing, the rectangle will only be 12mm x12mm.  Likewise, a 12mm x 12mm rectangle pasted into an inch based drawing will become 12”x12”.
 
Conversion Factors:
These common conversion factors will help you out as you keep reading:
1 inch is 25.4 mm
1 mm is 0.0393700787 inches

There are two easy ways to solving cross unit woes in AutoCAD.

Soft-Convert:
If you only need to dimension a drawing with different units (e.g. a metric drawing with imperial dimensions,) you can create a dimension style with a SCALE (Dimension Styles > Primary Units tab.) The SCALE is the conversion factor.
So if my SCALE is 25.4, when I dimension a 1” line the dimension shown will be 25.4 (1 x 25.4 = 25.4)

Advanced tip: If you want to forgo the dialogue boxes, you can edit the current dimension style's scale directly by changing the value of the DIMLFAC variable.  Note that DIMLFAC creates a dimension style override (named "Style Overrides") that only alters the scale of the current dimension style.
 
Hard-Convert:
If you need to actually draw in imperial units when the drawing is in metric units, you will need to scale the objects in the drawing from mm to inch (or vice versa).  No settings or variables here; simply select everything in the drawing and use the scale command (& the correct conversion factors) to resize everything to your desired measurement unit. Now draw away.

A Note on Insertion Scale:
Something important to note. Many people get waylaid by the "Insertion Scale" field in the "Units" dialogue box. This does automatically scale inserted content to the selected unit, but only when you are inserting objects such as blocks, drawings, or images. If you need to paste cross-unit objects between drawings, writing them to a block and inserting may be your best bet. If you want, you can use the INSUNITS variable to change this setting.

Optional tip. You can also set the "Insertion Scale" to Unitless and specify the default source and target units in the "Options/User Preferences" dialogue box. Inserted objects will automatically scale between the source and target units you set, regardless of what unit the drawing file was created with.

The most useful information ends here. For those who program LISP routines, a rant follows...

It boggles my mind that AutoCAD does not have an optional real-time scaling factor built-in for drawing differing units in the same drawing. This would consist of 1) a global drawing unit, as supplied by the user or the template. This would tell Autocad what measurement unit the drawing is in. 2) A scaling factor would be calculated and applied to objects as they are drawn. AutoCAD would compare the entered unit to the global unit and apply the appropriate conversion factor to object drawn or edited. Perhaps the same can be achieved using a LISP routine. If there are any takers, please drop me a line.

Go go West Virginia. I’m back at the Contemporary American Theatre Festival in Shepherdstown, WV for the summer. Its amazing how much life is put on hold during summer stock. Unfortunately there are not any outlandish scenic requirements. Though the schedule is outlandish in its own right. That’s the summer stock life for ya’. The shows are fairly straightforward, though we are using a ridiculous amount of blood this summer, which should make changeovers bundles o’ fun. I’ll post some pictures later on.

Added an article about creating wicked bright flicker lamps. Read it here or in the sidebar. See the pictures here.

Recently designed a radio play for the Long Wharf Theatre Radio Auction. Unfortunately air time became limited, so we could only broadcast one six minute scene. Good new everybody! The play is available for download here. Downloads as zipped MP3s. 80Days.zip

The Long Wharf Radio Theatre Presents: Around the World in 80 Days. Adapted from the Orson Wells' Mercury Theatre Radio play (based on Jules Verne's book by the same title.)

You may remember the Theatre Mysteries Project. Oh, that site died a slow death of neglect. The coup de grâce came when I decided not to renew the domain registration. So I packed up, moved across town, and set up shop somewhere else. I feel liberated from the constant self-nagging to keep the old site updated with new bits. The TMP was for other people, this one is for me. I have decided to narrow my focus and write articles documenting projects that I am currently or have previously worked on. This will also serve as a place for me to house files pertinent to my work. Perhaps I'll throw down a blog or two every once and a while.