IEC Receptical cut in chassis Question

[Platefire]

I preparing to install my first IEC type cord. The IEC receptical is like a rectangle with the bottom corners angled off. My normal fair would be to drill holes to allow access for a hand jig saw with a metal blade to make the cut---and then just cut out a rectangular hole (ignoring the angles) and then drilling side screw holes for mounting. Of course de-mill the cut to remove slag. This cut is kind of close quarters for my normal fair-so some pointers on how to best do this would be appreciated. I did go through the Hoffman info to find something on this but didn't see anything. Thanks, Platefire

[jjasilli]

I use a cutting wheel on a dremel tool.  They come in different diameters.  As you use them they wear down and the diameter gets smaller so they can make those shorter cuts. 

[tubenit]

I use a cutting wheel on a dremel tool.  They come in different diameters.  As you use them they wear down and the diameter gets smaller so they can make those shorter cuts.   

1+

[Platefire]

I have a Black and Decker version of the Dremel. I think it accepts regular Dremel tools. Thanks, I will check it out. Platefire

[stingray_65]

Just last night I used my Dremmel Multi Max to cut a square hole in a piece of 1/8" aluminum.

Has a slight learning curve to it, skipped about a bit, but nice smooth cuts with little cleanup /file work.

I also know that a rotozip works well too, I've done lots of PT cutouts with it, use the right bit though Sabre cut comes to mind. and not as neat as the multi max.


Ray

[sluckey]

A nibbler works very well  for rectangular cutouts too, but if I had a dremel I'd probably use that. AES has them and Radioshack may still have them.

[kagliostro]

I've exactly the model of nibbler that Sluckey posted

the only problem with that, is the thickness of the chassis

Kagliostro

[LooseChange]

I nibble and I dremel.  Aluminum is easy to nibble. For Steel I use the dremel with the cutoff wheel.

[sluckey]

I nibble and I dremel.

I feel so dirty after reading that!   

 

[LooseChange]

 

[plexi50]

Does this make you feel any better?

[rafe]

that make me dribble and tremble

[punkykatt]

Now thats scary.

[jojokeo]

I made a template out of 3x5 card material (or anything thicker than ordinary paper will do) that I use to trace the actual dimensions of the cutout w/ the angled corners using a sharpie. Then I drill a small hole in the middle. Next I use a step drill bit cutting out to size minimizing the next step for the nibbler staying w/in the lines. No need to get perfect and then I use a couple various width files for the final shaping. AFTER the hole is done then is the best time for making the small mounting holes as a last step. Then they will be lined up perfectly to the hole. Works every time w/out power tools and cutting wheels.
This is actually very quick when you get the hang of it and the files make short work of also deburring any edges. There is great control w/ this method.
I've used cutting wheels before while even doing woodworking and they are an unncessary danger IMHO. I've cut myself before as this can happen very easily. Hospital visits, stitches, loss of playing time, or even permant injury isn't worth the risk to save a couple of minutes. I don't take that risk or chance any longer.

[The_Gaz]

Looks great, what gauge aluminum is that?

[RicharD]

That looks like stainless steel.

[jojokeo]

Nah, that's just a typical aluminum Hammond chassis. I do have one made w/ steel though. You can see how badly surface rust forms when working w/ steel from the first & 2nd pics. In the last one after powder coating, it's so black in the real picture I had to lighten it up a bunch to even be able to see the holes and cut-outs. But, the drilling, nibbling, & filing method worked great on the steel too.

[jojokeo]

Having a file size issue w/ the site for some reason? Here's the last powder coated pic of the result.

[G._Hoffman]

The bit cutter speed for aluminum is the same as for wood, so you can use a standard router with carbide bits, though you have to feed it a little slower than with wood.  If you use a pattern bit and any kind of jig (I just use a strong double stick tape and some plywood scrap straight edges), you can get very good cutouts.  You do want to rough drill/cut out most of the scrap first.  DON'T try it with steel bits, but carbide bits work great.  You don't want to use too heavy of a cut, but then that is always the case if you want a good finish out of a router.


Gabriel

[Platefire]

Well my chassis is steel I do like the template method of using a step drill. I'll have to go by radio shack to see if they have nibs. I will also check out the demel cutters for one to fit my Black & Decker. Thanks for all the pointers on this. I'll just need to take my time and do it right. Platefire

[G._Hoffman]

Of course, and I don't think I've seen this mentioned, the best way to do it is with a rectangular punch.  The lip of the IEC receptacle will cover an appropriately sized rectangle (at least, with the ones I use).  The only problem is that the punch is bloody expensive.  A good punch should work on most steel up to the gauges you are likely to be using for a guitar amp.


Gabriel

[LooseChange]

Well my chassis is steel

I have cut MANY IEC holes is Hammond steel chassis.
I mark the chassis with a Rectangle template and just start cutting. I drill no holes.
I use a dremel with a Heavy Duty Cut-Off Wheel Number 420. They come in a package of 20.

You need to go slow and steady. It usually takes two to do the job. They wear out to nothing and very occasionally they do break.

[overtone]

Of course, and I don't think I've seen this mentioned, the best way to do it is with a rectangular punch.

+1.
I am investing in punches as and when I see a good secondhand one.
Metal work.. it's not my cup of tea anyway. It always seems to get me really close to having to learn how to fret like Django Reinhardt...

[LooseChange]

I've seen a punch made just for the IEC and almost bought one. But when I went looking again, I could not find that one or one like it.

[Fresh_Start]

If McMaster Carr doesn't stock it, you don't need it... just kidding:
http://www.mcmaster.com/#knockout-punches/=bbuz50

Not specifically for IEC, but a rectangular one would get very close to the IEC sockets without a fuse.  Darned expensive unless you're building a LOT of amps though.

I've got to agree with jojokeo about the risk of power tools for this application.  Instead of drilling one big hole in the middle, I drilled a series of small (1/8" maybe?) around the inside edge of the opening I wanted.  A nibbler would've been great, but it wasn't too bad just using a small rat-tail file to remove material between holes and then a flat file to clean up the edges.

Cheers,

Chip