Enclosure drilling - please advise

[Perrow]

I'm new to drilling enclosures and have a limited set of tools, that does not include a drill press, nor the budget to get one. What I do have is an electric drill, a rechargeable drill and a dremel. I've used the dremel to drill some pilot holes but didn't like the experience much. From what I've read, aluminium should be drilled at quite low rpm and that is not a property the dremel likes (nor exhibits) much.

So what is my best choice? I would think it's actually the rechargeable as it has less rpm. Does it matter if I use regular drills or a reamer? How much preassure should I apply?

[rockhorst]

Get a good set of drills for metal/aluminum with the sizes you need. If you can find a 13mm or 1/2" drill, be careful with it since most hand drills don't like the big sizes too much. Find a way to clamp your enclosure, other than your hand and just have a go with it. I doubt you'll ruin a box, even at the first try. The DC jack is going to be the most difficult.

[darron]

aluminium can take a faster speed than steel. it's very soft metal, even the high quality hammond enclosures which aren't watered down as much....


you could also look at a stopped still bit instead of a set. it might help you keep the registration since you don't have a press.


also, with a stepper, if you get the pilot hole off or the holes is only a mm or two out you can put pressure to one direction and drill slowly and it will drill out to one side.

[Perrow]

I've got a descent set of metal drills and I think I can clamp down the enclosure good enough. The stepped drills I could get were only 2mm steps, so I went with the conical drill instead. I guess you're right, I could have a go at the 10mm holes I need, good margin for error there. If all else fails I do have my trusted diamond bits, gonna need to use those anyway for some special holes on this project.

[defaced]

Diamond bits are for drilling things that are very hard like glass.  If you use a diamond bit on aluminum, you will clog the bit with aluminum. 

I agree with the previous posters, a clamp, hand drill, and a step will get you started.  Be prepared to kill a box as a sacrifice to the learning gods. 

[Perrow]

Diamond bits are for drilling things that are very hard like glass.  If you use a diamond bit on aluminum, you will clog the bit with aluminum. 

I agree with the previous posters, a clamp, hand drill, and a step will get you started.  Be prepared to kill a box as a sacrifice to the learning gods. 

You're probably right about the diamond bit getting clogged, hadn't thought about that. Guess I'll use the little sandpaper bits for my Dremel instead.

And no, no. No box killing, no, not me 

[defaced]

Those won't fare any better.  They'll clog too, but they're alot cheaper to replace.  I find working with soft metals is very annoying because of the clogging issue.  This extends past abrasive removal (sanding drums, grinding discs) and into files, burrs, etc.  


Edit: something I remember reading recently, I've not tried it, but supposedly if you use your tools on paraffin wax before grinding aluminum, you won't clog the tool.  Might be worth a shot if you run into problems.  And if it doesn't work, blame the guys on the American Welding Society forum

[runmikeyrun]

Get a center punch from a hardware store.  They have a spring loaded steel point that clicks and makes a tiny indent when you push it all the way down.  It keeps the drill bit from wandering when you start drilling.  I usually drill a 1/8" pilot hole and then follow up with whatever size I need from there.

[PRR]

> aluminium should be drilled at quite low rpm

Drill aluminum like wood.

"RPM" depends on diameter. You really want a certain MPH at the cutting lip. This means high RPM for small holes, low RPM for large holes.

However the motor-makers know typical cutting speeds, and aimed their drills to a suitable RPM. Little 1/8" (3mm) bits can turn 10,000RPM, the Dremel in in this zone. 3/8" (10mm) bits can turn 4000RPM if you have enough horsepower; common 3/8" handy-drills turn 2,500, you cut a little slower but cost/weight are lower. A Hole-Hog turns up to 4" bits at 600RPM and takes two hands to carry.

Boffing pot-holes in pot-metal... bah, just do it. Plain HSS twist drills or the UniBit.

Your common 1/4"-3/8" drills, plug or battery, will be perfect-enough for drill bits half the chuck size to full chuck size.

They are "slow" for smaller bits, but what is your hurry? A right-RPM rig does a small hole in one second, it takes you 3 seconds at reduced RPM, it's fine. As you say, ripping along at 10,000 RPM can be unpleasant.

Affordable drill motors can strain on bits larger than their chuck. 1/2" is fine with light pressure. But in steel, pretty slow (you want a bigger motor). They will swing 1-3/8" in soft wood, using a spade-bit (no self-feed bite) and a light touch. I just did 1-3/8" through dense softwood 6" deep... that took a while, with breaks to rest myself and the motor. I shudda borrowed a Hole-Hog (I'm not about to BUY a $700 tool to hang a $5 lamp once).

[Perrow]

I actually went at it with the cordless drill today, went like a charm. New drills and increase in one millimeter steps. Haven't tried the conical bit yet, will do in a few minutes I'll get back to you on how it went. I do have a hole that needs to move over a bit as it gets wider, that'll be fun to see how it goes, thankfully it needs to go up to 10mm.

[derevaun]

I sometimes use this kind of tapered reamer:



Available at most hardware stores. If you mark the hole dimensions on the box, you can "steer" pretty effectively. It also doesn't grab shavings and scratch the finish with them. I think Craig Anderton suggested it in EPFM?

[Perrow]

Thanks for all the help, got it all drilled now. Satisfied with the result, all 15 holes pretty much where I wanted them

Started painting. This project might actually be done in a near future, kind of hard to believe when I've been planning and working on it for (I think) more than a year 

[EATyourGuitar]

if you dont want to scratch your paint when drilling, you can cover it in painters tape and draw your drill template right on the tape. it also protects the left side while your drilling the right side. I use a framing square that has a 45 degree straight edge. I draw an X that comes from the corners and I have my centerline for the foot switch. I can draw vertical or horizontal lines. I have a ruler on the framing square if I want to measure something. I can connect the lines all around the box to make sure the jacks match on both sides. I use a irwin stepped bit and a $60 drill press. not changing bits is a HUGE advantage. I dont need to use a hole punch with the tape/pencil/drill press. if you are using a hand drill, a hole punch and a stepped bit is a must.

[deadastronaut]

I sometimes use this kind of tapered reamer:



Available at most hardware stores. If you mark the hole dimensions on the box, you can "steer" pretty effectively. It also doesn't grab shavings and scratch the finish with them. I think Craig Anderton suggested it in EPFM?

me too, my drill will only go up to 10mm bits.so i use a reamer the same as that one^  .(havent got a unibit yet). its a handy tool to have..

i haven't a drill press either, i do it dangerously with my foot holding it on a block of wood.. .., i always centre punch then drill pilot holes first... 

[MikeH]

I do almost all of my drilling with a typical cordless 18v drill.  It's best to with the piece clamped to a bench (or a table you don't mind accidentally drilling holes through).  Most of those drills have a tightness clutch type thingy on them (usually a # 1-20 something).  I always set this around 15 or so, that way if the bit hangs up, the clutch slips, instead of the drill jerking out of my hand, or ripping the box out of the clamp and slamming it into my groin.

Pilot holes are a must. Step-bits a GREAT but expensive.  If you cant get one, drill a few holes - ie, if you're drilling a 1/2" hole, start with a small pilot hole, then do about 1/4, then 3/8, then use the 1/2" bit.

[Perrow]

Thanks Mike, that's exactly how I did it, though as I'm a modern man, I used metric drills

My work bench is set up in a storage room I clutched the enclosure to the leg (what do you call them?) of a bookshelf. Worked out quite nice as I could put the garbage bin below while drilling, so most of the metal flakes ended up there

[nexekho]

I use a hole punch.  Or a screwdriver and something heavy.  Maybe some scissors to widen it.

--professionalism;

[Perrow]

I use a hole punch.  Or a screwdriver and something heavy.  Maybe some scissors to widen it.

--professionalism;

If violence doesn't solve it, try more violence.