I’ve finished an ANSI Chain Calculator; you’ll find it in the main index.  It calculates the following:

• Physical properties of standard ANSI chains (multi-strands too),
• Pitch length to inch length converter
• Estimated chain elongation calculation
• Estimated chain weight per length of selected chain
• Center-to-center calculators for a two-sprocket system, calculating by sprocket centers or by chain length
• Sprocket properties for the selected chain size, including pitch diameter, outside diameter, and tooth width.

The Fleet Angle calculator now calculates by offset, angle, and distance.  Change any one variable and the other two update. I’ve also added a diagram.

The Frustum Flattener was updated, the new navigation bar wasn’t working correctly.

The Resultant Force calculator code was updated; it would sometimes fail to re-calculate when changed.

Note that I’ve moved the the diagrams.  They used to be located below the calculators (akk).  I’ve moved them into a pop-up dialogue that you can load by clicking the “Diagram” button, as shown below…

While I do work primarily in the entertainment industry, I like to keep an eye on the larger world of CAD news.  Here’s the current list of CAD related blogs I keep up with…

Design and Motion

SolidSmack – Product Design, CAD, Prototyping, etc.  Of EvD Media fame, highly recommend their podcast, Engineer Vs. Designer.  Oh, note to self, podcasts are a post for the future…

MasterGraphics blog – these guys have some good tips and tricks, found them while searching from info on Inventor tips.

Lazy Drafter

CAD Insider – This one goes way out of my discipline, but its still interesting to read up on general industry and CAD/CAM/CAE news

Autodesk Personnel

Ellen Finkelstein’s Blog - Usually more basic tips, but every once and a while there’s an obscure bit.

Heidi Hwewtt’s Blog – heidihewett.blogs.com

Between the Lines - from Shaan Hurley

Through the Interface - Coding (mostly in .net) for Autodesk products, from Kean Walmsley

## Update, and calculators

Yes, I’m still alive.  No, I haven’t posted in over a year.  Yes, I’m still working for a large live entertainment company.

A quick update, the earlier calculator scripts that I mentioned in the last few posts are no longer working.  I’ve instead been working on a unified collection of calculators using the jquery mobile framework; the aim is to be phone and tablet friendly.   Catch it in the links above, or here.

My two favorites are the Unit Converter and the HP/Force/Speed estimator.  I’ll be adding more as I find the time.

## Fluid Power Calculator

I’ve been playing around with learning javascript recently.  I’ve thrown together a fluid power calculator as a “hello world”.  You can find it here: Fluid Power Calculator It’s not pretty, but it works pretty well.  (See what I did there?)  You can download the page and run it locally if you want.

My ultimate goal is to transfer all of my theatre-related excel calculators to javascript powered web pages, so I can access them wherever I happen to be.

## Scratch! v. 1.2 released

Scratch – the scratchpad layer utility for AutoCAD – has been updated to version 1.2!

Hard to believe its been over a year since I released an update to Scratch.  This update is kind of a sea change for the program, see the notes below.  On another note, this is the last release I am going to issue; I use it every day, and it hasn’t been an active development project for a while.  I might post a short screencast describing how to use it.  I hope you get as much use out of it as I have.  And be forewarned, I’ve got some really cool stuff I’ve been working on.

Usage:

Note: the  symbol is a backtick (next to the 1 key)

• command:  – toggle between scratchpad layer and the current layer
• command: e – erase scratchpad (menu)
• option: a – erase everything in scratchpad layer
• option: p – preview all objects in scratchpad layer
• option: s – erase only selected objects in scratchpad layer
• command: m – move selected objects to the scratchpad layer
• command: 1 – jumps to previous layer

Release notes:

• consolidated scratch into one file
• changed CST command to
• changed EST command to e
• added options to the erase constructions (e) command
• added move object(s) to scratch layer command (x`)
• general bugfixes
• general performance refinements and code slimming

## Wiki going down…

I’ve decided to do away with the scenic-shop wiki.  I’ve little patience for cleaning up the spam and junk that kept accumulating.  It was quite the failed experiment in any case; I’m both disappointed and frustrated with the outcome.  This makes two failed attempts at starting up an open forum for technical theatre solutions.  Why the failure?  1) Perhaps writing for a wiki format is too challenging or takes too long; though I would describe very few of the successful stagehands I know as slow – so that’s probably not the reason.  2) Perhaps folks don’t want to publish technical solutions without a byline to claim credit.  3) Maybe we’re much more secretive and feudal than I thought.  4) Maybe our free time should be spent drinking beer and eating nachos.  Whatever the reason, there’s still the stagecraft mailing list, yale tech shorts (see what I did there?), Google Groups and the Technical Director’s forum.

I hope I don’t sound bitter, that’s not what I’m going for at all.  I’m still convinced that there’s a way to implement a community driven reference site, I just don’t know what shape it will take.

Peace out.

## Twist Lisp

Did you know you can precisely rotate the current view of modelspace?  This is a killer way to simplify drafting and dimensioning objects on an angle, especially if you have a way to align the current view to an object.  (And we do, keep reading.)

The longhand command is Dview > Dviewblock > Twist.  Enter the angle you want to twist the current view to, and you’re set.  Why type that out every time?  This lisp will do that and more – just type “TW” to invoke.

Command : TW

• Enter the twist angle explicitly (e.g. 45 or -134.25) or…
• Align: set twist angle by picking two points (Point 1 is 0,0 and Point 2 is positive x-axis vector)
• Relative: set twist angle relative to current twist angle
• After twisting the view, the list will prompt yes(default)/no to realign the UCS to the current angle.

Right now the script only does the twist in modelspace, I’m planning on expanding it to work in paperspace & viewports as well.  When I get some free time that is.

Until next time – keep it lazy.

## Pianos & Steel. CAD Block Giveaway!

I just realized I never posted those grand piano cad blocks I promised months ago.  You can snag them here (version 2k).  Egg. face. mine.

While I’m at it – this is a link to some commonly used steel profile blocks.  Some of them are dynamic, so you’ll need a newer (2006? I’m too lazy to look it up right now) version of autocad to utilize them.  Inside you’ll find:

• Common (small) rectangular tubing (d-d-d-d-dynamic!)
• Angle Iron (dynamic)
• 1 5/8″ Unistrut
• 280 Track
• Iron Pipe (dynamic)
• 2×4 metal stud

## Site Update

For the three people who keep up with this blog, you’ve probably noticed that I haven’t updated at all in the past several months.  Sorry about that – I’ve recently taken an engineering gig for Production Resource Group‘s scene shop, which includes confidentiality agreements and such.  At this point I’m not sure what is and isn’t considered a trade secret, so I’m holding off on posting any solutions derived from work.  Its a shame, I’ve always been of the mind that information should be free, especially in the theatre.  Ah the price we pay for growing up and moving on to bigger things.  This blog will continue, but it will probably shift even more to AutoCAD related scripts and such.  Now that I’m working at a different shop I’ve been drafting different stuff, and have a boatload of new ideas.  I’ve already started work on several routines; they’ll be up when they’re fit for public consumption.