How on Earth do I cut small rectangular holes for slide switches?

[luap77]

Hi,

I'm really struggling to make neat rectangular holes in a 1590BB Hammond-style diecast aluminium box (2-3 mm thickness). The holes are needed for small slide switches and need to be about 5mm wide by 15mm long (very small).

So please, could you share some of your ways of making small rectangular holes?

Thanks!

Paul E

[brett]

Hi
We've all been there.
I eventually bought a "nibbler".  Cost about US$10, but it has saved many times that in grief.

cheers

[Barcode80]

also, a dremel with a tile attachment has worked well for me on aluminum, so you can route out very close to the rectangle you need and then use a small metal file to corner it up

[captntasty]

Perhaps drill a series of holes at the desired width and enough in a series to allow for the slider, then file out the rounded points and corners until square.  That's the not so quick and dirty way but doesn't require any other tools than what you probably have... or maybe you need to get a file for rough and then a set of small hobby files for corners and fine tuning the channel.

[coxter]

  got a link to the nibbler?

[Dave_B]

What part of the world are you in?

[coxter]

Singapore. Havent heard of the nibbler.. lol

[luap77]

Can the nibbler really cut a rectangular hole that's only 5mm wide by 15mm long in the middle of a panel, or do you need a bigger hole to start it (or an edge to start from)?

Thank you

[pyrop]

You can get them at Jaycar & DSE
Jaycar CAT. NO. TH1768 $19.95au
From Jaycar

Will cut any shape out of aluminium, plastic, copper and other unhardened metals up to 18 gauge. Tool is designed to fit into the palm of your hand for easy use, simply drill a 1/4" hole to start.

DSE CAT. NO. T4945 $17.98au
From DSE

Allows you to cut almost any shape or size of hole in sheet steel to 0.6mm thick or light alloy to 1.5mm thick. It follows curved or straight lines with ease and is also great for use on many plastics.

Might be worth trying Bunnings as well

pyrop
 

[smnm]

wow - I could use one of these too - RS also sell em - search for 'nibbling tool' (excuse preposterous URL)

http://rswww.com/cgi-bin/bv/rswww/searchBrowseAction.do?com.broadvision.session.new=Yes&D=Nibbling%20Tools&Ntt=Nibbling%20Tools&Ntk=I18NAll&Ntx=mode%20matchany&N=0&Nty=1&name=SiteStandard&forwardingPage=line&R=2508758454&callingPage=/jsp/search/search.jsp&BV_SessionID=@@@@0088119113.1161243509@@@@&BV_EngineID=ccckaddjeeffhijcefeceefdffhdfgg.0&cacheID=uknetscape&Nr=avl:uk

[luap77]

So it looks like a nibbler won't work for me as a 1/4" (6.35mm) starting hole is bigger than the 5mm wide rectangular slot I want to cut. Also, the aluminium is thicker than the nibbler seems to allow.

I've got an idea though...I think I can drill a series of holes as captntasty suggested, then use a square file to make the slot. The trick that I'll employ is to clamp two bits of much harder metal (i.e flat tool steel) either side of the holes and exactly 5mm apart. This will ensure that the file cannot stray out of the 5mm slot that I want to cut, as well as hopefully giving true rectangular holes i.e. parallel sides. Kinda like a cutting guide if you like. For the top and bottom of the slots I'll move the clamped guides to the top and bottom and finish these with nice 90 degree corners.

Does this make any sense to anybody?

Paul E

[stobiepole]

Rip apart one of your switches. Take the metal bit that goes around the switch - that's your template. If you're using the kind of switch that has screw holes, you're set. Drill the holes, screw the outside bit into the holes and drill out the inside.

Um, could I be any clearer? Sure, have a look at this for a pictorial example of what I'm trying to describe:

http://mmmonkey.co.uk/console/sega/md1switches.htm

Chris

[darron]

if you wanna go ultra pro, just get them laser cut. laser cutting is VERY cheap... i got a quote to have my pedals lasered for like $10 AU each which i have normally been etching... take into consideration the cost of pnp blue, the ferric chloride, and the massive pain in the ..butt.. i had trying to iron on the transfers, it sound heaps easier, and about the same cost the way i was going!

[pedaltastic]

if you wanna go ultra pro, just get them laser cut. laser cutting is VERY cheap... i got a quote to have my pedals lasered for like $10 AU each which i have normally been etching... take into consideration the cost of pnp blue, the ferric chloride, and the massive pain in the ..butt.. i had trying to iron on the transfers, it sound heaps easier, and about the same cost the way i was going!

Where do you get them lasered? It does sound like a good idea - can you laser designs on them as well then?

[Mark Hammer]

Nibblers are wonderful, but far more wonderful on sheet metal aluminum chassis - where a quick light squeeze does the job - than on cast aluminum chassis, where your hands might ache for days.  If I remember correctly, the purpose of this forum is to help make stuff for playing music, and that particular purpose needs hands....that don't hurt.  I don't know about you, but the thought of not being able to open a pickle jar for days, because of a hand cramp, does not sit well with me, or with the other pickle-lovers in my household.

The start-with-a-dremel-and-end-with-a-flat-file method works fine for me.  The nice thing about the 1590x series is that they machine easily with both drills and files.  You can also bevel/smooth the sides of the slot with the file which might make for a nicer finish and less risk to one's fingers when using the switch.

[drj]

another vote here for the Dremel - file way of doing square cut outs for switches

use a flat needle file to finish off the slot, a needle file removes less material than a hand file so you can achieve a neat finish with clean square corners

[Doug_H]

Amp builders go through this all the time with IEC connectors for power. There was a guy at ax84 that was talking about punching square holes for IEC's in a circular "adapter" he was going to machine that would mount in a standard size round hole and selling them. Real convenient for people who don't have access to a square punch (hard to find I've been led to believe). I don't know how he ever did with that. It might make a nice cottage industry for someone though.

For pedals, I just avoid stuff that requires square holes. I would suggest subbing a toggle or pull-switch on a pot for your slide switch.

[Mark Hammer]

Toggles and pot w/switches are certainly a plus as far as ease of machining, but if you have something like a power switch for a dual-battery unit, and you don't want the power switch to be accidentally moved during transport, there is no substitute for a low-profile slide switch.  As well, there are plenty of obscure slide switches out there that will do things no comemrcially available toggle will do.  E.g., I picked up some 3-position 4-pole slide switches.

[MikeH]

How do you guys mount your slide switches in a die-cast enclosure.  The only sliders I've seen have screw mounts; seems like that would be a pain on anything thicker than sheet metal.

[darron]

if you wanna go ultra pro, just get them laser cut. laser cutting is VERY cheap... i got a quote to have my pedals lasered for like $10 AU each which i have normally been etching... take into consideration the cost of pnp blue, the ferric chloride, and the massive pain in the ..butt.. i had trying to iron on the transfers, it sound heaps easier, and about the same cost the way i was going!

Where do you get them lasered? It does sound like a good idea - can you laser designs on them as well then?

look in the yellow pages for a local place. and yes you can get designs lazered onto them. that's also what i was talking about. some places will tell you it's impossible to get a design lazered onto aluminium, some places will tell you that their machines aren't strong enough. lucky for me there's a place walking distance who can do it deep enough to spray. lasering/lazering aluminum actually leaves a white etch...