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What do you guys use to drill holes on chassis??

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jamesjung21

jamesjung21

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Joined 2003
#1
G'd day!

What do you guys use to drill holes for tube sockets on a metal chassis?? A reamer to enlarge holes to right sizes??😕

Only bi-metal holesaws seem to work well on metal (esp. steel), but they are quite expensive...

Is there any alternative method that you guys use?

Cheers,
JayJay
 
#2
I use Greenlee hole punches. They make perfect holes with no burrs or bent metal.

If you are using aluminum you can also use a 'unibit' stepped drill bit with multiple sizes on one bit. It looks like a tall pyramid with a step ever 1/4" and a change of 1/8" per step.
 
#3
Hole punches
Stepped drill bits on aluminum, mild steel
Bi-Metal hole saws
A drill press comes in handy!
And a reemer where needed. Good for removing burrs!
Sometimes you can catch them on sale. If you drill alot of holes they are worth it...
Have a look here, you'll be amazed at what you can find using the search button! 😀 😉

www.diyaudio.com/forums/showthread.php?s=&threadid=31339&highlight=

And here:

www.diyaudio.com/forums/showthread.php?s=&threadid=3981&perpage=10&highlight=&pagenumber=2

Wayne
 
#4
A chassis punch.

Hand reamers produce octagonal holes. Hole saws are inaccurate (to guide), produce a lot of heat and an inaccurate messy hole. Stepped drills are inaccurate, incredibly noisy, and quite dangerous; other than that, they're fine.

I've used all of them. A chassis punch costs less than the valve that's going in there.

If you're really impecunious, use an Abrafile in a full-size hacksaw frame. You need a fair amount of skill...
 
#6
Shopping list for ECL82 amplifier:

4 x ECL82
mains transformer
2 x output transformers
connectors
Rs & Cs
Bridgeport milling machine




Personally, I'd love a Bridgeport in place of my Emco clone, but what with one thing and another...
 
#7
I'll be a nice guy this time and not do what I did when the subject of electron microscopes came up (posted a picture of me leaning on mine with a big grin on my face).

OTOH, I'd love to have a nice DSO with FFT capability like yours. I'll put that on my shopping list, right below the blond twin stewardesses.
 
#9
EC8010 said:
A chassis punch.

Hand reamers produce octagonal holes. Hole saws are inaccurate (to guide), produce a lot of heat and an inaccurate messy hole. Stepped drills are inaccurate, incredibly noisy, and quite dangerous; other than that, they're fine.

I've used all of them. A chassis punch costs less than the valve that's going in there.

If you're really impecunious, use an Abrafile in a full-size hacksaw frame. You need a fair amount of skill...
Click to expand...
Where do you get your punches from? A good quality Greenlee can cost from $30 to $250 depending on size and shape!
 
#10
Hole saws are inaccurate (to guide), produce a lot of heat and an inaccurate messy hole. Stepped drills are inaccurate, incredibly noisy, and quite dangerous; other than that, they're fine.
Click to expand...

Yupp! That's why I use a (big **s) drill press where I can. I try to steer away from hole saws, very inaccurate-HOT! Buy two hole punches, sizes 3/4" (19-20mm), and 1 1/8" (29-30mm). I only use reemers for small holes, like for screws and such to enlarge slightly, de-burr. Stepped bits work fine if you take your time and use a good drill press (at the right speed) and a piece of scrap wood underneath for support.
And for front panels or thick metal you could use/send out to Front Panel Express using a neat, fun free program to design, layout your panels or even a chassis!

www.frontpanelexpress.com/

Wayne
 
#11
Since I only use 1/8" and 3/16" thick aluminum for chassis, hole saws and step drills work just fine. The less run-out your drill press has, the better your results with a step drill. ALWAYS use a cutting fluid specified for aluminum when drilling holes, you won't regret it. I also finish the inside of holes made with a hole saw (1" dia. to 2" dia.) with a small, inexpensive drum sander.

John
 
#13
I'm lazy. I either use scrap thin ply for protos, or when it's finalised I draw it up and take it to a small metalshop and get them to do it. Look in the yellowpages, there'll be places in most large cities that do large AV and security CCTV installs and will have most connector holepunches and can do the others. I like front panels and top plates out of thick aluminium or brass. It's usually not expensive and you get pro results.
 
#15
For some of my more serious projects I´ve had help from my brother to cut the holes. He runs a wire EDM at work, and that machine is just perfect for making chassis!
You can cut PERFECT holes in anything from thin aluminium to several inches of hardened steel...😀
 
#16
Enzo said:
In the USA anyway, you can get Greenlees from ANtique Elec. For $30-$45. My Greenlee 1" has been with me now for over 45 years. My 3/4 almost as long, and the 1-1/8 is just a kid at 25 years plus. I think the prices are reasonable for that kind of life.

Antique is www.tubesandmore.com

Also look at W.W.Grainger www.grainger.com
Click to expand...




www.mcmastercarr.com
 
#17
I'm also fortunate, as mr Fuling above, in that i can call on help from others. I can warmly recommend WATERCUTTING your chassis, it will give you very nice results, without the hassle. My brother-in-law made a top plate from my autocad drawing, out of nice 4mm aluminium.

Rgds
yac
 
#18
Nothing beats proper machinery when it comes to cutting round holes.
My brother talked about making a set of hole punches in the right sizes for the most common tube sockets, I guess he´s a bit tired of programming that EDM. The way he explained it seemed easy enough to make a few, and he has the skills and tools so why not.
 
#19
Fuling said:
Nothing beats proper machinery when it comes to cutting round holes.
My brother talked about making a set of hole punches in the right sizes for the most common tube sockets, I guess he´s a bit tired of programming that EDM. The way he explained it seemed easy enough to make a few, and he has the skills and tools so why not.
Click to expand...
If you have the access to the hard steel and a machine to form the cutter out of it, it would still be cheaper to buy one. You need a really good roller bearing and a very high grade bolt too.
 
#20
A word about Greenlee punches from a person who has used and abused more than my fair share:

Its easy to let the die slip causing scratches in the chassis.

They really do work best on thin non ferrous metals. I’ve found that using them on steel cover plates for 1900 boxes and larger pull boxes is pushing their limits. Lots of oil on the threads and cutting surfaces is advisable. These plates are roughly 1/8" galvanized steel.

If you can find a deal on the Greenlee die holder, its likely worth the money if your planning more than occasional use. It holds both pieces and has a ratchet handle making it less likely to scratch your work piece.

I’ve heard good things about Front Panel Express and have a project that I'm dying to try out with them. I have however found the free layout software a little limiting in its capabilities.

A Bridgeport with CNC is my dream too. It would be nice to have it do engraved lettering too.
 
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