Cutting panels

Hi,

I need to fabricate a "patch panel" for a network distribution point. Most COTS panels are fabricated in multiples of 12 or 24.

E.g., 1x12, 1x24 (as 12+12), 4x24, etc.

Graphically, something like:

1x12 XXXXXXXXXXXX

1x24 XXXXXXXXXXXX XXXXXXXXXXXX

4x24 XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX

Each 'X' being an 8P8C RJ45S connector.

Typically, these "connector assemblies" are fastened to the rear of an aluminum plate while the connectors themselves protrude through holes in that plate (actually, since the connectors typically abut each other, the holes are really long *slots*)

[Sorry if all this is obvious -- if you've seen one such panel, you'd understand what I mean]

In my particular case (1-off), I need to fabricate two "3x12" panels:

XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX

My problem is cutting these long slots in some material (e.g., aluminum) in a manner that doesn't look amateurish. [I suspect these slots are punched in commercial offerings so they are nice and square, etc.]

You *know* aluminum with a file is going to look like "aluminum with a file" :< I just can't imagine keeping nice hard, straight edges going that route!

So, I'm exploring other fabrication options. E.g., perhaps replace the aluminum with lexan? (though I'm not sure that will be any easier to machine -- "hot knife"?)

[I have a friend with several wire EDM's but can't bring myself to ask for that big of a favor! :-/ ]

Currently, I figure the easiest solution is to find a couple of

4x24 panels and cut them each in "half" (more like 55/45%] discarding the undersized "halves".

Is there some other trick I can explore? Anything *strong* that can be "molded"/poured? (the panels have to support a fair bit of force as things are plugged/unplugged "carelessly")

Thanks!

--don

Reply to
Don Y
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If you have a technical sheet metal shop in your area (not the roofing 
kind) that may be the way to go.
Reply to
John Fields

Search for "custom panel laser cut metal"

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Roberto Waltman 

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Reply to
Roberto Waltman

I'm don't know what type of connector will go in the slot, but many have a small lip to cover minor flaws. I if indeed the job is 3 long slots and not 36 small slots, I would fabricate it myself with a jigsaw and a file. I usually scribe lines in the aluminum and put a fresh coat of masking tape on the bottom of my jigsaw to protect the material, then grab the proper glasses, and lighting for good vision. I'd mount the aluminum securely maybe in a vise, maybe screwed to a piece of wood. You might want to change the masking tape part way through. Use a variable speed jigsaw and a new blade (I like the bimetal) and take your time and take breaks. If your not up to that, make a drawing and take it to a machine shop.

I bought one of these panels for a system using RJ45s

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I bought it for the parts when I put together a temperature monitoring system for 13 freezers. (A "One Wire" system) Mikek

Reply to
amdx

Not sure why you'd see filed edges in this case. If you mean the outsides of a cut panel I do this:

a. File with a coarse file, then a fine one.

b. Go over it with an electric sander and 240-grit paper or similar.

c. Go over it by hand with 600-grit paper.

d. If I want to be extra good I go over it once more with 600-grit and chalk in it. Commercial product does not live up to that.

A pint of Guinness can help with that :-)

IME they all have a lip. Else they'd fall out the back :-)

That's exactly how I do it. I use a Bosch 230V jig saw running a bit slow on 120V, makes nice clean cuts. You just have to resist the temptation of rushing the job by pushing too hard.

I clamp it to a wooden workbench. Also with some masking tape so the clamps won't mar the aluminum.

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Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

For just one, find someone with a manual mill and have the slots milled. Maybe post on rec.crafts.metalworking and tell where you are and maybe someone will volunteer. Or find a machine shop in your area. Laser cutting, punching, or cnc milling will all cost twice as much because of the set up and programming involved. If you want five or ten or more, then that gets spread out and doesn't matter much, but for one the overhead is a killer.

----- Regards, Carl Ijames

John Fields wrote:

Search for "custom panel laser cut metal"

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Roberto Waltman 

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Reply to
Carl Ijames

Or use the situation as the perfect excuse to get one of these:

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It's still less than what most wives spend on shoes, handbags and such in a year :-)

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Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

(slaps head) D'oh! Friend with EDM's probably still has a few Bridgeports in the back room for jobs that are too small to setup on the wire cutters! I.e., no real "set-up" involved using a mill (compared to "programming" the EDM's). This is a much *smaller* favor to ask... ;-)

Exactly. Old school is the only practical way to go if you are going to have someone else do it for you.

Thanks! That gives me a more practical approach (though still leaves "those who follow" in a bind...)

--don

Reply to
Don Y

Personally that would be my preferred route. My experience with trying to be "clever" with one-off fabrication is that it inevitably ends up being more trouble than doing the job the proper way to start with.

The trick to something like that is roughing out the piece quickly and easily. The small carborundum cutting/grinding discs that fit in a PCB drill save a hell of a lot of time. A scroll saw with a fine blade saves even more. If you only need to pull out the files to shave off the last fraction of a millimetre the job takes a little time but it's not hard and the results can be quite satisfactory.

In your case keystone jecks have mounting lugs on the front panel that will visually break up the straight lines in any event - I doubt you'd really notice any minor imperfections.

OTOH I really would prefer brass to aluminium even if it does cost substantially more - aluminium always seems a lot less forgiving, in that one accidental light contact with a tool creates a ding you can't polish out. Since you are cutting long thin slots in sheet you may well want the additional strength too.

Two possibilities come to mind. The first would be photo-etching, as for PCBs but on metal sheet. Etching from both sides you can cut through moderate thicknesses - perhaps say 1.5mm. I'd suggest a grid pattern of holes (one for each connector) as opposed to slots in thin material - it's no extra work and will strengthen things up quite nicely. You can also add surface detail by etching those only from one side, so for example you can have labels etched in the front and fold lines in the back.

Again I'd prefer brass for strength at a given thickness. You can certainly etch aluminium but you need weak etchant - either well diluted or almost spent. With "good" etchant things are rather too fast and uncontrolled, and you get uneven results because of it.

On a similiar vein would be a CNC mill of the style you sometimes see advertised for PCB manufacture. In the long term those would probably be the best bet but of course the capital cost is rather high for a one-off project. I've no experience of those for this kind of thing but I must admit I've been tempted to blow £1000 on one.

--
Andrew Smallshaw 
andrews@sdf.lonestar.org
Reply to
andrews

Most of the units I've seen (I've accumulated quite a nice collection! :> ) have the connectors *peek* through the slots in the front metal plate, mounted from behind.

For example: Note the "black dots" -- each a boss/stand-off that's supporting the PCB onto which the individual connectors are mounted.

Or: which has some alternate thumbnails showing detail of the openings in the panel -- along with a view of the back side.

E.g., a PCB (or, a set of PCB's) is mounted behind the panel. On one side of the PCB, the connectors are mounted. On the reverse side, a series of punch-down blocks (the third thumbnail) which are connected to the connectors via traces on the PCB's.

Viewed "end-on" sighting down the row of connectors, you have:

CCCC ========== B B

where CCCC represents the connector's body and B the punchdown blocks.

But, the epiphany is hidden in your phrase: "a small lip to cover minor flaws"! I.e., while the connectors themselves don't have such a lip, there's nothing to prevent me from *making* one!

Specifically, creating a "precise" veneer to mask any ugliness in the fabrication of the "metal/lexan panel". I.e., use the panel for structural support and adhere a thin (rigid) plastic veneer *to* it!

You could precisely cut the slots in that veneer with a good straight edge and sharp xacto knife. Heck, you could even make it out of an exotic *wood* veneer: "Be the first on your block to have a Mahogany patch panel!" :>

With the veneer approach, you could be *really* crude in how well you cut the slots. And, "filing" would only be necessary to remove burrs, etc.

Yes, I like this idea! It's something that others could easily reproduce and get "good" results -- all while avoiding the need to locate some "service" to do the work for you!

Reply to
Don Y

Oh, yes! A rigid (thin) sheet of plastic onto which is adhered a nice, *legended* applique (photographically reproduced from a Photoshop/Illustrator file created on your PC for $2 at your local Costco, etc.). Make things look *really* professional/custom! Much cleaner than scribbling what each connector services *on* the panel itself!

And, for little/no money! Finestkind!

Reply to
Don Y

Hi Joerg,

[Are you threatened by fires?]

Then you've got to find a place to *store* the damn thing! :< (I've been procrastinating buying a tile/wet saw for exactly this reason)

You need to find yourself a less-expensive model!! ;-)

[I now have *three* pair of shoes and it has left me stressed to the max! Never can find the pair I want to wear... ]

--don

Reply to
Don Y

No. Outside is easy -- you can bring power tools to bear (belt sanders, etc.) But, when cutting a long, thin slot/opening in the interior of the piece, your choices quickly get limited. Esp if you want nice square corners, etc.

The ones I've seen are all *mounted* from the back. See the images (URL) I posted in another reply.

--don

Reply to
Don Y

And it's from Harbor Freight, so you know it's a well-designed, high-quality piece of gear. :)

--
Grant
Reply to
Grant Edwards

Well, in my teenage days I did both inside and outside strictly by hand. The only power tool I had, and only on occasion, was dad's electric drill. But strictly no milling or routing with that because it would have ruined the bearings. When I was 15 or so my parents gave me a new Metabo drill but I didn't want to wreck its bearings either. I didn't really have any other power tools until after my EE degree except for a huge and rather dangerous home-brew grinder.

For the insides I glued sandpaper on a piece of plywood, made the smoothing job quite easy.

True, when they are on a PCB they do not cover the slots. But it ain't so bad to get the slots done cleanly. A couple of years ago I did that for an audio rack. Looked like it came that way from the manufacturer.

Back in Europe engineers had to go through part of the apprentice program that journeymen go through. It teaches students precision filing and all that. We were only allowed to use simple power tools such as the drill press. And woe to him whose piece of workmanship was 0.005" off somewhere. The master would make you start all over, from scratch.

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Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

Hey, can you elaborate on that Costco deal? I am always looking for a fast way to make nice-looking front panels. Do they offer some sort of thick-plastic printing?

[...]
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Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

Not yet. We live 35mi east of Sacramento.

[...]

I wear down at least one pair/year, sometimes two. My car mileage is around 2000mi/year, my hoofing mileage in the same ballpark. Yet the cost for shoes for myself is easily $100/year while the pro-rated car tire expenditures are less than half that. Day and night quality difference. It's so not fair.

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Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

This was under the assumption of occasional use, not industrial 24/7 use. So far Harborfreight stuff has been good to me.

--
Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

So the price for one 3x12 panel is $539.99 PLUS the cost of material and labor.

Cheap at twice the price ! ;-)

Reply to
hamilton

Dunno. I was just advocating a *regular* 8x10 glossy photo print rubber cemented onto a plastic/aluminum panel. That way, you can get the "graphics" as a commodity product.

[Realistically, a glossy photo would probably not fare well. But, that doesn't mean you can't take advantage of some other "print from PC" technology to come up with a nice legended overlay. I.e., separate the cosmetic from the structural requirements...]

Decades ago, we used to make those stick on "serial number/product ID" plates on a 1-off basis in the blueprint room. Some sort of aluminum(?) with a black coating that could be etched away (or, maybe it was *deposited*?). With the sort of technology available today (photo processes), it should be possible to do at least that same sort of thing (IIRC, we made a template from clear film and stick on lettering -- then "exposed" this onto the aluminum product)

In any case, something like the above solution(s) should be available for hobbyists trying to make 1-offs without dropping a lot of money into something with little *functional* value.

Reply to
Don Y

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