I hope this is the correct forum for this question. If not, my apologies.
As I have been putting together tube amplifiers recently, I have been running into issues based on my complete inability to cut a rectangular hole in a metal enclosure.
I have no problems drilling holes; for RCA jacks, for speaker outputs, for tubes, for mounting various things like transformers and standoffs and so on. All holes. Holes are easy.
However, every chassis needs power, and power means the ubiquitous IEC input jack for three-prong wires in the USA.
Invariably, I manage to mangle the cutout. I hate it!
Does anyone have any alternatives to the IEC power jack? Or alternatively, any tips on how to cut the blasted rectangular hole correctly with hand tools? I don't have a shop, not even a drill press. I have a hand drill and a set of chassis punches, nothing else. It has worked for me so far, but when it comes to IEC power ports, I'm like Jack the Ripper on those poor enclosures.
Help!
As I have been putting together tube amplifiers recently, I have been running into issues based on my complete inability to cut a rectangular hole in a metal enclosure.
I have no problems drilling holes; for RCA jacks, for speaker outputs, for tubes, for mounting various things like transformers and standoffs and so on. All holes. Holes are easy.
However, every chassis needs power, and power means the ubiquitous IEC input jack for three-prong wires in the USA.
Invariably, I manage to mangle the cutout. I hate it!
Does anyone have any alternatives to the IEC power jack? Or alternatively, any tips on how to cut the blasted rectangular hole correctly with hand tools? I don't have a shop, not even a drill press. I have a hand drill and a set of chassis punches, nothing else. It has worked for me so far, but when it comes to IEC power ports, I'm like Jack the Ripper on those poor enclosures.
Help!
Here you go, this mounts in a round 1 3/4" hole. You're welcome.
5239 > Flanged Inlets > Straight Blade Wiring Devices > Electrical Wiring Devices > Products from Leviton Electrical and Electronic Products
http://www.walmart.com/ip/39109721?...53840071&wl4=&wl5=pla&wl6=88030084871&veh=sem
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A connector like that can be mounted either from within or from the outside. If you mount it from the outside, then the flange around it hides your ragged hole edges. In fact, look closely at the photo you posted. I can see barely peeking out from behind, the two upper corners of the chassis hole it is mounted in.
In the cases where I have to make that hole, I make a round hole as large as I can in the space. A step drill works for that. Then I use a nibbler tool, or a Dremel bit, or even a file, to expand the round hole out into the corners.
When I was a kid, 60 years ago, I had a few drill bits, and a hand cranked drill. To make holes for tube sockets, I would drill a pattern of 1/8" holes in a circle, then knock out the center by snipping through the "perforations" I had made. That left a very rouch round hole, which I smoothed with files and a burring ream.
In the cases where I have to make that hole, I make a round hole as large as I can in the space. A step drill works for that. Then I use a nibbler tool, or a Dremel bit, or even a file, to expand the round hole out into the corners.
When I was a kid, 60 years ago, I had a few drill bits, and a hand cranked drill. To make holes for tube sockets, I would drill a pattern of 1/8" holes in a circle, then knock out the center by snipping through the "perforations" I had made. That left a very rouch round hole, which I smoothed with files and a burring ream.
I know what you're saying, but you don't appreciate the level of my inability to cut a straight line of any kind!
I have indeed cut out rectangles for the IEC that I tried to 'hide' the ragged holes; it was like that time I tried to fool my parents by moving the footstool to cover the place I burned in the carpet when I was a kid (not quite 40 years ago when I actually was a kid). I'm just that bad at it!
Round inlets and outlets are the standard for higher power/voltage connections.
Industry wouldn't put up with these cheesy consumer toy parts.
http://www.hubbellcatalog.com/wiring/catalogpages/section-b.pdf
Why not just use PowerCon.?
powerCON 20 A - Neutrik
Not too expensive and it all over the pro audio world these days.
powerCON 20 A - Neutrik
Not too expensive and it all over the pro audio world these days.
The "5-15P" type designation of that one reminds me of another "round" alternative. Users who will likely not travel a lot with their stuff (or take the matching power cord) when using someting like the 5-15P for mains, might also consider the venerable XLR-predecessor. The once-ubiquitous Cannon P3-13 connector fits a 1.5" hole, so you need some back-panel real estate. Oh, and just make sure no-one tries to plug the power cord into some vintage mic connection
While the P3-13P does't come with UL/CSA/etc certification for 125Vac, both the 5-15P and the venerable Cannon would likely also be usable for 240Vac as connectors are spaced very far apart. The Cannon had 1500Vdc rating if memory serves me right.
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The Power Conn is the way to go, I also am starting to see it all over the place, specially in powered monitors and such, where the locking possibility is useful.
I must frown on any hare brained idea of using XLR or any typically Audio connector for Mains, the potential for Death (won't even worry about material damage) is immense.
I don't care if pins are rated 10000V , the grave problem lies in the possibility of connecting live mains to audio equipment killing unsuspecting users.
I must frown on any hare brained idea of using XLR or any typically Audio connector for Mains, the potential for Death (won't even worry about material damage) is immense.
I don't care if pins are rated 10000V , the grave problem lies in the possibility of connecting live mains to audio equipment killing unsuspecting users.
Yeah, I understand. I did actually think about using XLR or other types of audio-style connectors before posting. Although my equipment is highly unlikely to ever be around anyone who might not know it's a power jack and not an audio input or output, nevertheless I share your concern. Just for the sake of conformity and safety, I wanted to try to use something that at the very least could not be mistaken for something else. I'm liking that Neutrik a lot.
Thanks, but I have no Dremel. I have tried very carefully to perform a similar operation with four pilot holes and a nibbler; my result would be considered a crime in many countries. I have also tried to use a keyhole saw (broke all the blades in 10 minutes) and some flat files (made holes too big and also cut myself).
I am not handy. I just want to drill a round hole for a round power receptacle, rather than attempt to become handy at my advanced age.
I certainly appreciate all attempts to school me on how to cut a proper rectangular hole, but please understand I have tried and failed. I suck at that, and I really don't plan to try it anymore. I need a different solution that matches my lack of ability to make rectangular holes.
Yes, I have also considered that. Having a power cable that can be disconnected facilitates moving it around my house without tripping over the cable, etc. It just seemed like a good thing to have. Also kind of nice to have a single power cable and multiple amps, plugging in each one as desired. I never listen to more than one amplifier at a time.
I've had good fortune laying out the square with square, ruler, pen or pencil, drilling the 4 holes, nibbling a smaller hole than needed, and filing up to my line.
Another helpful tool is a small bench vice to hold the work piece steady, particularly for the filing.
Avoids having to insert a switch. Especially if one has to bring the Mains feed from the back to the front of the amp for a front mounted switch.why you have to disconect power cable
I started using a rear mounted switch for ClassAB that were left on all the time.
Then I graduated to no switch. Just pull the plug out.
I do like to use a switch, but I understand what you mean about the wiring issue under the chassis. The Neutrik Powercon connectors I'm looking at specifically say they are not designed to be inserted or removed while under power, so that's a concern if I were to eliminate the power switch.
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