[time-nuts] Excellent equipment rack

paul swed paulswedb at gmail.com
Tue Jun 11 18:42:05 UTC 2019


I have found my racks at the MIT flea in the past.
The great thing about 2 posters is they easily come apart and can fit in
the car.
Plus the pieces by themselves are reasonable in weight.
Regards
Paul

On Tue, Jun 11, 2019 at 2:05 PM Tom Knox <actast at hotmail.com> wrote:

> Hi All;
> I have found when rack hunting it is best to look at local test equipment
> auctions. Even really nice racks often do not receive any bids and more
> importantly no shipping. In my labs I use exclusively Agilent/Keysight
> because they are exceptional quality and parts a commonly available. The
> one minor problem is they are a touch narrow, and some items like Wavelek
> calibrators are a really tight fit, but workable. I find in local auctions
> when they show up they are (like other racks) usually very inexpensive. The
> trick is if you have any plan to go to racks in the future start looking
> early and buy when you see them even if not yet prepared to use them and
> store them until needed.
> Hope that helps
>
> Tom Knox
>
> 303-554-0307
>
> actast at hotmail.com
>
> "Peace is not the absence of violence, but the presence of Justice" Both
> MLK and Albert Einstein
>
> ________________________________
> From: time-nuts <time-nuts-bounces at lists.febo.com> on behalf of Bob
> Albert via time-nuts <time-nuts at lists.febo.com>
> Sent: Tuesday, June 11, 2019 9:59 AM
> To: Perry Sandeen via time-nuts
> Cc: Bob Albert
> Subject: Re: [time-nuts] Excellent equipment rack
>
> Very interesting!  Recently I had a somewhat similar experience.  My
> neighbor was throwing out some shelving that looked like what I need.  It
> was gray steel, all the vertical parts needed but no shelves.  I made
> shelves from plywood and ended up with a nice addition to my lab.  To make
> it mobile I sat it on a dolly that fit almost perfectly so now I can move
> it.
> I put my VNA and some tools on it and it's a perfect fit in the corner of
> the room.
> Just because I am an electronics engineer doesn't mean I can't do
> mechanical stuff.
> Bob
>     On Tuesday, June 11, 2019, 08:00:43 AM PDT, Glenn Little WB4UIV <
> glennmaillist at bellsouth.net> wrote:
>
>  Here is what a U is:
>
> Main article: Rack unit <https://en.wikipedia.org/wiki/Rack_unit>
>
> Racks are divided into regions, 44.50 millimeters (1.752??in) in height,
> within which there are three complete hole pairs in a vertically
> symmetric pattern, the holes being centered 6.35 millimeters (0.25??in),
> 22.25 millimeters (0.88??in), and 38.15 millimeters (1.50??in) from the
> top or bottom of the region. Such a region is commonly known as a *U*,
> for /unit/, or, in German, *HE*, for /H??heneinheit
> <https://de.wikipedia.org/wiki/H%C3%B6heneinheit>/, and heights within
> racks are measured by this unit. Rack-mountable equipment is usually
> designed to occupy some integer number of U. For example, an
> oscilloscope <https://en.wikipedia.org/wiki/Oscilloscope> might be 4U
> high, and rack-mountable computers are mostly between 1U and 4U high. A
> blade server <https://en.wikipedia.org/wiki/Blade_server> enclosure
> might require 10U.
>
> Occasionally, one may see fractional U devices such as a 1.5U server,
> but these are much less common.
>
> The height of a rack can vary from a few inches, such as in a broadcast
> console, to a floor mounted rack whose interior is 45 rack units (200.2
> centimeters or 78.82 inches) high, with 42U being a common
> configuration. Many wall-mounted industrial equipment enclosures have
> 19-inch rack rails to support mounting of equipment.
>
>
> A R-390 is 10.5 inches tall so it is 6U.
>
> Your rack could be drilled for using mounting screws of: 10-32, 12-24,
> M6 or require a nut plate for equipment mounting.
>
> 73
> Glenn
>
> On 6/11/2019 2:02 AM, Perry Sandeen via time-nuts wrote:
> > Yo Bubba Dudes!,
> > Needing to go vertical with my test equipment I went bottom feeding for
> an equipment cabinet on ebay.
> > To make a long search story short: they were way too expensive, too
> heavy to ship and too far away for pickup.
> > So I kept searching and finally came across what was listed as *42U Four
> Post Open Frame Server Data Rack 19 inches.?? Adjustable depth 23 to 32
> inches.ebay number 152319524877.Sold by Raising Electronics for US $188 and
> free shipping.
> > I was unsure what a *U* height meant put it seemed tall enough so I
> bought one.
> > I was a little apprehensive about this being a Chinese metal product.??
> I was very pleasantly proven very wrong.
> > Although it only comes with a picture of an assembled unit it has been
> engine ed so there is no way you can assemble improperly. The four posts
> are all equal and can be installed with any end up or down and the top and
> bottom brackets will fit.?? It comes with the exact 50 M6-20 head bolts and
> nuts needed for assembly.?? The nearest SAE equivalent bolt size is 1/4 20
> x 1/2L which I purchased to hold L shelf brackets to the frame.
> > I set the depth of mine to 26 inches so my 5370's fit well and I had
> space for both power and BNC cables to be inside the frame.
> >
> > This rack is designed to be bolted to the floor.?? Wanting to be able to
> move it, I cut a piece of 3/4 inch plywood a little longer and wider then
> the base footprint and installed 4 inch tall Harbor Freight swivel casters
> on the four corners for ease of movement in any direction, even on floor
> carpeting.?? After assembly it was 6 ft 9 inches tall.
> >
> > Now this being a bolted together *skeleton frame* it is prone to
> twisting and or becoming a parallelogram sideways.?? To prevent twisting, I
> fitted a plywood board on the top bolted to the top front and rear angle
> pieces.?? To prevent a side-to-side movement required an 8 inch wide piece
> of scrap aluminum plate bolted to the rear vertical posts.?? This is easy
> to do as there are a plethora of precision spaced holes available.
> > There was some very serious thought given to the vertical post design.??
> It has six 90 degree folds done in such a way that the inner edge on each
> outer side gives a 19 inch opening.
> >  ??However behind it is as inner fold where one can install recessed L
> shaped brackets. Now the inner fold is about and inch narrower than the
> outside edge.This allows making a wider shelf that can *float* on top the
> brackets but can't slide out either end.
> > This was very useful when configuring the instrument arrangement.
> > I also found that with the bottom shelf being just 6 inches above the
> floor I was able to install more equipment in the same vertical space than
> in my previous normal sized equipment cabinet.
> > Another bonus with this type of configuration is that it's easier to
> keep the equipment cool and it's much lighter.
> > Regards,
> > Perrier
> >
> >
> >
> >
> > _______________________________________________
> > time-nuts mailing list -- time-nuts at lists.febo.com
> > To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> > and follow the instructions there.
>
> --
> -----------------------------------------------------------------------
> Glenn Little                ARRL Technical Specialist  QCWA  LM 28417
> Amateur Callsign:  WB4UIV            wb4uiv at arrl.net    AMSAT LM 2178
> QTH:  Goose Creek, SC USA (EM92xx)  USSVI LM  NRA LM  SBE ARRL TAPR
> "It is not the class of license that the Amateur holds but the class
> of the Amateur that holds the license"
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>



More information about the Time-nuts_lists.febo.com mailing list