Cannabilizing Rackmount Chassis?

[exclamationmark]

I'm looking for a rack mount unit to jam my pre-amp into, and new racks run from anywhere from $150 to $200 plus postage... I'm a bit of a noob at rack mounts, but would it feasible to tear into something like a 24 port switch I can buy for like 20 bucks (or even get for free...) and simply replace the face/backplate with custom machined ones? I can't really find any 'gut shots' of these switches to see if there's anything funky going in on the inside.

Anyone with experience with rack mounts care to chime in?

[Steve Conner]

I built this years ago. Toaster pics

It was made out of a 3U high "Eurocard" chassis (don't know if you have those over there) dumpster-dived from a university engineering department. I made the front, back, top and bottom panels myself, getting some help from a friend who had a milling machine to make the front.

You could probably do something similar with a rackmount network switch, yes. Or look for some dead 19" rack audio gadget on Craigslist etc.

Or try harder, you should be able to get a new rack for less than $150. Here's a huge one for $59.54: BUD INDUSTRIES|RM-14212|CHASSIS, RACK MOUNT, 4.281IN, | Newark.com

and a 1U one for $39 http://www.newark.com/bud-industries...num/dp/05M4042 (top cover seems to be sold separately, though)

[R.G.]

I don't know if you're in the USA (and hence shipping would not break you, maybe) but google "Middle Atlantic" and look at some of their rackmount chassis. The 1U is under US$50, and the 2U is not much more.

On the other hand, yes, it is quite feasible to cannibalize a small pre-existing rackmount. The only issue is that there is a lot more machining to do to make it usable and presentable. Unless the money is just not there, I'd buy the thing.

Here's one link to a vendor. The 1U is $43, the 2U is $53.

[exclamationmark]

The mouser sorting system is next to useless. For some reason half of the actual chassis products were listed under "accessories for racks and cabinets" rather than under "rack enclosures"...50 bucks ain't bad for a 1u or that humongous 3u compared to what I was looking at from Hammond.

Anyway... I found a guy who lives not too far away selling some switches for $5 a pop (I get to choose too ), so I might just crack one open and see what I find in regards to replacing panels.

[exclamationmark]

I don't know if you're in the USA (and hence shipping would not break you, maybe) but google "Middle Atlantic" and look at some of their rackmount chassis. The 1U is under US$50, and the 2U is not much more.

On the other hand, yes, it is quite feasible to cannibalize a small pre-existing rackmount. The only issue is that there is a lot more machining to do to make it usable and presentable. Unless the money is just not there, I'd buy the thing.

Here's one link to a vendor. The 1U is $43, the 2U is $53.

I'm in Australia, so shipping is rather expensive (like $40 expensive!). I'm ordering some knick-knacks through mouser soon so I'd like to lump in everything through there. I think the shipping would probably be my main concern in ordering anything at the moment, especially with 'surcharge taxable' heavy stuff like racks. Not really looking for anything too presentable at the moment, just something I can mount the pre-amp in so it's no longer being held together on my desk by 18 gauge wire and protoboards. Gonna get the front panel done by.... frontpanelexpress, which is quite cheap at around $30. The shipping is actually going to cost more than the machining/material cost! All depends on what sort of racks I find, though. Some have just plain awkward ways of construction.

[R.G.]

If you're willing to have a front panel machined like that, consider an overlay front panel. Make your front panel a bit smaller than the existing one on the box, and just screw attach it over the whole front of the old panel. Cut away enough of the old front panel to allow mounting whatever controls and displays you need. The new panel completely hides the old one and not as much care is needed in modifying the old front panel, which is left in place and covered up.

[exclamationmark]

I think I may actually go with the bud industries rack, because I actually get free shipping with mouser if my order is over $200. Hopefully they won't charge me extra for handling or I'm back to step 1. I have decent fabrication skills so I'll probably just drill/punch whatever holes I need and ghetto stencil controls on it (doesn't look as bad as you might think...)

[J M Fahey]

Dear Steve.
I know you Scots are real macho men (such as using kilts while wadding through waist high snow), but do you really need to run your amps *that* hot?

Yea, I know it's called "The Toaster", yet ......
I guess it would cook one of our "bife de chorizo" (a 1 inch thick steak) in about 10 minutes.

No, I'm not angry, I'm smiling, my face got that red by all the infrared radiating from your picture.
I'll better go get my suntan lotion.

[Steve Conner]

First of all, sorry, I didn't realise you were in Australia. (You never said. ) I guess AU$ 150 doesn't seem that out of line when you consider all the import duties and so on.

JM: That was a very long time exposure taken on colour print film, back before digital cameras were invented. It turned out very strangely. The tubes look like they're about to undergo nuclear meltdown, but the glow didn't look abnormal to the naked eye. The plates certainly weren't red.

They are the Russian 6p3s, "relabelled as 6L6GC by an unscrupulous dealer" as Dr. Tube puts it.

[J M Fahey]

I know, I was just joking.
I'm also a photographer, straight from the black-and-white Jurassic age.
I love night photography so I'm quite used to *long* exposures .
Oh well.

[JacksonRR]

Steve, I took a look at your toaster build and that thing is FECKIN SWEET MAN!!! I really dig the whole vibe. Looks wonderful on that mic'd cab all by itself, not it a rack.

[J M Fahey]

*There is* another solution to the pesky rack problem.
If you can get a regular chassis that's 43 cm wide, or can have sheet aluminum cut to that width, you can build a rack mountable preamp or power amplifier for peanuts.
Why 43 cm? It's the "magic number".
If you find it can work for you I can post a tutorial.
*Any* of my breadwinning amplifiers can be rackmounted if so asked by the customer.
Only 2U and 3U high; 1U is beyond my practical possibilities.