Cutting Chassis to Fit IEC Receptacle

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Bernard

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I am thinking that it would be interesting to replace the captive power cord on my ARC SP9 preamp with an IEC receptacle, so I can try out different power cords. I do have a few power cords I would like to try. The problem I have, though, is how would I go about cutting the chassis (which I imagine is steel) in order to install the receptacle ? Would a chassis punch work (if at all, and if I can find the right size) without distorting the metal ?

Any ideas? I only have rudimentary tools.
 
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jewellers saw - like a coping saw but with a much finer blade/tooth. Lee Valley Tools has them (among many other places, but LVT is in Ottawa and will have the people there to properly advice you).

however i'd be really worried about metal dust getting into the components.....
 
jewellers saw - like a coping saw but with a much finer blade/tooth. Lee Valley Tools has them (among many other places, but LVT is in Ottawa and will have the people there to properly advice you).
Yeah, the company is just a few miles down the road from me.

however i'd be really worried about metal dust getting into the components.....
Me too, but I know that companies like Great Northern Sound do it as part of their mods. Perhaps with a vacuum going at the same time ?
 
Roberto, I have that tool from Radio Shack. It's good for cutting tin, but I doubt it would so the trick on a steel chassis.
 
Whatever you use to cut the hole, I would have a magnet near the site to catch any errant metal chips.
 
This seems to cut a nice hole. :ROFL:

T270088-Experimental_laser_cutting_device_on_robot_arm-SPL.jpg
 
Yeah, the company is just a few miles down the road from me.

Me too, but I know that companies like Great Northern Sound do it as part of their mods. Perhaps with a vacuum going at the same time ?

i was thinking shopvac with a concentrated nozzle, but the magnet is interesing too. LV sells rare-earth.

i used to live on Kelly Ave, in west ottawa. we looked over the townhomes and could just see LV (original site). they moved from there to the old roller rink i haunted in the 80's. blast from my past.
 
Hi Bernard,

Just for giggles, why don't you cut the power cord at say one inch from the back plate and install a new female IEC fitting.

Once this is in place, you can install the power cord of your choice and determine if you can here a difference.

If this doesn't work, go for the back plate surgery.

Gordon
 
Hi Bernard,

Just for giggles, why don't you cut the power cord at say one inch from the back plate and install a new female IEC fitting.

Once this is in place, you can install the power cord of your choice and determine if you can here a difference.

If this doesn't work, go for the back plate surgery.

Gordon
Gordon,

Interesting suggestion, but a female IEC fitting will not mate with a female plug. The IEC fitting would have to be male; the male has the, ahem, prongs :)

I do know what you mean. One problem though is that once the cable is cut there is no turning back, and back surgery is needed, unless of course I replace the cut cable with the original (now shortened) captive cable.
 
Sorry Bernard,

I got my male / female mixed up.

It does seem like a good option before cutting the back plate.

Gordon
 
The manual nibbler will be the cheapest to use and fairly clean, as it is punching out a small rectangle with every squeeze of the handles. Go slow to make sure you line up from the previous cut to get a straight line.

A square IEC chassis punch would be the best tool but you must be able to get the die into where you want the hole and the die is large. Also it will run you around $300 for one. They are not cheap.

Other manual options inclued drills, saws, files or a Dremel tool with a metal cutting blade. All will work but create metal dust and filings you will need to protect against getting all over the unit.
 
ARC enclosures are more often aluminium which is quite easy to cut. You might want to apply some protective tape around the section to be removed.
 
I've toyed with making this mod to my SP-9 too, but the relatively tight space between the fuse and the toroidal transformer gives me pause (not to mention, cutting the back plate: as you say, one you start, there's no going back).
 
About five years ago I did the modification to my CJ MF-2500A that had a capture cord. I simply removed the cord from the back panel, then traced the back side of the IEC socket and used a small three sided metal file to cut the open to the pattern I traced. Drilled two holes to secure the socket and off I went. The modification transform my entire system. (just joking) Now I never thought about the metal shavings, I suppose I got lucky. Sam
 
The modification transform my entire system. (just joking) Now I never thought about the metal shavings, I suppose I got lucky. Sam
Seattle Sam :),

What kind of difference, if any, did you hear ?
 
Bernard, you know it was so long ago that I don,t remember.personally I. Don,t think it was not that significant. I did the mod based on what my dealer told me,that I would gain 20 percent improvement. I bought a mid priced Shunyata power cord and left it plug in ever since. Never experimented with any other cords. I am one of those guys who's not convince that spending a lot money and time on power cords is going to make a worth while improvment.At the same time I am glad I did the mod, if for nothing else I have a beefy cord that is supplying great music to the Summits. Sam
 
i am thinking that it would be interesting to replace the captive power cord on my arc sp9 preamp with an iec receptacle, so i can try out different power cords. I do have a few power cords i would like to try. The problem i have, though, is how would i go about cutting the chassis (which i imagine is steel) in order to install the receptacle ? Would a chassis punch work (if at all, and if i can find the right size) without distorting the metal ?

Any ideas? I only have rudimentary tools.

you should be using a 'dremel' rotary tool
 
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