Now this is interesting. On the inside cover page of the handbooks (say, the PDP11/45 handbook) you?ll find the company name ?digital equipment corporation? with two different shapes for ?t?, with a long bottom arc in ?equipment? and a short one in the others where there?s a letter to the right. Similarly, the ?r? has a short arc in that text. In the bezel as shown on the photo, the ?t? is consistently the long-arc version. And the arc of the ?r? is longer than in the handbook. Yet another oddity: that same handbook cover page has ?processor handbook? in the same typeface. In that text, the ?r? have long arcs, longer than in ?corporation? on that page, longer even than on the bezel of the photo. And while it makes sense for the second ?r? of processor, it looks weird for the first one. Curious. It suggests that there wasn?t particularly close control over what the various draftsmen could draw in creating those pages, or bezels. paul

On 09/07/2015 20:58, Pete Turnbull wrote: [etc...] There does seem to be some variation between reported dimensions, so just in case anyone is wondering, mine were made with a 60cm certified engineer's steel rule and a digital micrometer, with the aid of x10 loupe where necessary. Maybe we're seeing batch variation and some of the dimensions have a bit of a tolerance :-) -- Pete Pete Turnbull

Wow, I wake up and you blokes on the other side of the world have been busy during the night working at getting a bunch of details for me :) Thanks Barry, Pete, Paul, Noel, Bill, Adam for your responses - the measurements and photos are exactly what I need. I'll go through them in detail soon and adjust the drawing. Paul: I will revisit the postscript file and fix up mine from it. There's a reason I try to avoid splines in my CAD drawings, a long time ago I did DXFs for laser cutting some keyrings (see http://web.aanet.com.au/~malikoff/jeep/keyring) using splines. The cutter operator replaced them with arcs owing to their software not being able to process it properly. Since then I've avoided splines for any drawing I do that has a chance of being exported as a DXF (or SVG for that matter) that is to be fed to a CNC device. I'll also follow up on your observation about the variations in the handbooks font, I'm sure I'll find them on bitsavers. Noel: fabulous! Thanks very much for the measurements, appreciate the use of calipers. I do agree that efi is a great DEC seller, I've bought some bits from him. I'll reluctantly pass on the blank panel though, our dollar is weak and the international postage rates have gone through the roof in recent times. Bill: wood would suffice I guess, but unlike wood, styrene sheet always has perfectly consistent working properties and as a long-time scale modeller I am extremely familiar with using it. I also have a number of large sheets of the stuff, in different thicknesses, ready to use. Adam: I appreciate your photos very much. One thing that intrigues me is the end-on photo IMG_3161. It appears the top edge projects further than the bottom by a tiny bit leading to a tapered appearance, but I assume the plane of the printed inset panel is parallel to the exterior mounting surfaces. If you don't mind I'll load that into CAD and do some overdrawing to determine if that's the case. Your lighting is good so I'll take the RGB values for the colours. BTW the first image won't load for me: '... cannot be displayed, because it contains errors'. Pete: also teriffic photos, thanks as well! Nice measurements especially the letter heights. That will be invaluable to make it a better drawing. I think I'll need to do a drawing of the whole unit and then have the measurements checked so I don't misinterpret your figures. Appreciate the use of a micrometer too. A common method of determining radii is to use an engineers radius guage. Failing that, try fitting a series of circular objects (coins etc.) which can then be measured with calipers or micrometer. So thanks again everyone, a super response. Steve.

steven at malikoff.com writes: It's not tapered; it just looks that way because I'm not holding it very straight in the photo. I've added a couple more end-on pictures that should show this more clearly: http://photos.offog.org/pdp11-panel/g/ It's a pretty big image. If your browser doesn't like it, try saving it and loading it in something else? I've added a lower-res version as well. Thanks, -- Adam Sampson <ats at offog.org> <http://offog.org/>

On Jul 10, 2015, at 8:48 AM, Paul Koning <paulkoning at comcast.net> wrote: I think CamBam hates splines too, although it will load them and work with them, just very slowly. I usually have to tell it to convert all splines to polyline approximations. I?ve never had any problems with splines with the lousy software I use with my vinyl cutter though. I load Illustrator 8 files and cut them without any issues. -- Follow me on twitter: @FozzTexx Check out my blog: http://insentricity.com

On 11/07/2015 01:21, steven at malikoff.com wrote: "flush with bottom edge?": yes, it is. b = 93.5mm at the position shown, but it's slightly tapered, presumably for purposes of injection moulding. If you measure it just above the flange (the part with thickness "i" in that photo) it's 94.5mm. I'd not noticed that before. d = 56.95mm g = 4.93mm - 4.98mm depending on exactly where/how I measure it h = 106mm i = 2.46mm j = 33.18mm k = 11.67mm L = 2.7mm where you drew the line, tapering to 2.3mm at the rear edge (for injection moulding again) m = 14.25mm q = 15.5mm r = 6.35mm (it's a 1/4" hole to clear a 10-32UNF machine screw, which screws into a Tinnerman nut on the top crossmember of the rack) s = 11.1mm (hard to be absolutely accurate with the tools I have, but that is suspiciously close to 7/16") t = 27.9mm where you've drawn it. You obviously realise it goes in further under the flange, radiused as shown in IMG_3144. u = 11.27mm a = 91.05mm (that's from upper surface to upper surface) v = 9.21mm (average of two corners) w = 2.53mm (this tapers as well, to 3.1mm at the base) x = 12.25mm y = 15.5mm (but on mine, the piece of the flange that y is the width of, is almost 1mm wider on one side, but only in the part hidden by the flange that Z points to) z = about 0.5mm - you're trying to measure the taper on the edge of the flange? Not easy to be accurate. That flat part, across which you're measuring "x" and "y", looks as if it goes all the way across the bottom in IMG_3161 (where you've measured "k") but it doesn't on mine. It only goes as far as you can see in IMG_3144, and there are machining marks in the plastic where the rest has been cut away - and from the look of the marks, they're in the mould. Bear in mind that as this was designed in the US, the design measurements and tools were almost certainly imperial rather than metric. So that radius was probably cut on the master with a 3/4" cutter, rather than 19mm. That makes the radius 3/8", which is 9.525mm: slightly larger than 9.50mm but closer to 9.5 than to 9.6. Though I doubt anyone cares much about 0.1mm here, let alone 0.025mm :-) -- Pete Pete Turnbull