Search for center point drills, or just grind a broken bit to a hyperbolic tapered point, a curve from outer diameter to pin point (not straight conical).
This power switch is one of many that accommodates a 10mm front panel
https://www.mouser.com/ProductDetai...LvB/%2bv6/w==&countrycode=US¤cycode=USD
Reading all of these posts and absorbing. Thanks for the ideas, please keep them coming
https://www.mouser.com/ProductDetai...LvB/%2bv6/w==&countrycode=US¤cycode=USD
Reading all of these posts and absorbing. Thanks for the ideas, please keep them coming
It puzzles me, when watching stuff on TV ( such as " Gas monkey garage " ), that you never see anyone use a drill press, especially when you see them in the background ( another annoyance is people " switching " stuff on/off by inserting/pulling out plugs, but I degress...). I thought a four fluted drill was called a core drill. I have had success using a 1/2 inch center drill to drill a thin ( 1/16 ) alloy panel for rca sockets, avoiding the lobing ( three sided ) hole that often happens when using a jobber drill. Turpentine was considered a good lub for alloy, especially for filling.
As others have said- If you're going to start drilling lots of holes in aluminum, buy a center drill and some cutting fluid.
Clamp the material to the drill press table securely. Run the smaller center drill at faster RPM, slow down the RPM some when using the drill bit.
I always told students to peck and drill- use the drill press handle and touch the drill on the metal, use a small brush with lubricant, bring the drill up, don't drill the hole by pushing the drill into the hole all at one time, that's what causes galling. Peck and drill.
Check youtube for some videos on drilling holes in aluminum. The video below shows peck drilling on a CNC machine, but you can do this on a drill press and your arm provides the peck drilling cycle.
Clamp the material to the drill press table securely. Run the smaller center drill at faster RPM, slow down the RPM some when using the drill bit.
I always told students to peck and drill- use the drill press handle and touch the drill on the metal, use a small brush with lubricant, bring the drill up, don't drill the hole by pushing the drill into the hole all at one time, that's what causes galling. Peck and drill.
Check youtube for some videos on drilling holes in aluminum. The video below shows peck drilling on a CNC machine, but you can do this on a drill press and your arm provides the peck drilling cycle.
BTW the risk of aluminium galling depends a lot on which alloy is involved. Pure Al is horrible, avoid it if you can as
its too soft to machine easily and leaves horrendous burrs. Some Al alloys seem to cut much better than others:
diecast aluminium boxes cut and drill wonderfully easy I've found, hardly producing any burrs at all.
One mistake to avoid is having too low a feed-rate, you should be cutting into the metal, not rubbing its surface.
Rubbing leads to rapid heating of the bit itself, it expands, then its easy for it to jam and break - lubrication helps cool the
bit too (especially water based cutting fluids). Proper cutting puts the heat into the chips, not the tool so much.
Al allows fairly agressive feeds and speeds for machining/drilling - you can look these up in tables, its worth checking out,
but note cooling become more important then. Without a drill press feed rates are basically guesswork and feel, so
do some practice if you have offcuts and want to gain confidence.
And yes, if the bit isn't sharp, don't use it, it will rub, it will heat up, it will expand, and probably break and damage the
work piece.
(not get jammed with chips). Two-flute mills are rather weak/bendy for harder metals though.
like connectors, so its not insuperable. 5mm plate ought to be plenty really 🙂 Though I suppose you might use the front panel as a
heatsink if its that thick!
its too soft to machine easily and leaves horrendous burrs. Some Al alloys seem to cut much better than others:
diecast aluminium boxes cut and drill wonderfully easy I've found, hardly producing any burrs at all.
One mistake to avoid is having too low a feed-rate, you should be cutting into the metal, not rubbing its surface.
Rubbing leads to rapid heating of the bit itself, it expands, then its easy for it to jam and break - lubrication helps cool the
bit too (especially water based cutting fluids). Proper cutting puts the heat into the chips, not the tool so much.
Al allows fairly agressive feeds and speeds for machining/drilling - you can look these up in tables, its worth checking out,
but note cooling become more important then. Without a drill press feed rates are basically guesswork and feel, so
do some practice if you have offcuts and want to gain confidence.
And yes, if the bit isn't sharp, don't use it, it will rub, it will heat up, it will expand, and probably break and damage the
work piece.
Indeed - but two-flute mill bits are designed for aluminium and also know as slot-drills as they can plunge cut more effectively
(not get jammed with chips). Two-flute mills are rather weak/bendy for harder metals though.
You can drill out the back with a larger slot-drill or endmill (or CNC?) to allow some components to fit a thick plate - especially round ones
like connectors, so its not insuperable. 5mm plate ought to be plenty really 🙂 Though I suppose you might use the front panel as a
heatsink if its that thick!
FYI/FWIW, a good primer: https://www.ctemag.com/news/articles/aluminum-can-be-hard-drill-despite-its-easy-rep
Step bits are usually only good for sheet metal up to 3mm thick.
You need to be drilling through the sizes with HSS steel twist drill bits.
Centre punch, then start around 3mm (or 1/8") and work your way up the sizes to final dimension.
Use lube - WD40 will do.
Drill press if you have got it, otherwise take care not to lean too hard into the smaller drill diameters. Take your time.
You can work out RPM from the cutting speed in meters or feet per minute...
https://en.wikipedia.org/wiki/Speeds_and_feeds
Worth reading, quite informative.
https://en.wikipedia.org/wiki/Speeds_and_feeds
Worth reading, quite informative.
Drill aluminum?
What a chore!!!
I Punch it.
Of course, have the needed presses and die sets, so only now and then use a drill, typically to add something to an already built amp which of course won´t fit in a 3 or 5 Ton mechanical press, but avoid that as the plague it is.
Just by chance, at this very moment I´m making a small 12V 16W powered cabinet (sporting a 6" ex roof mounted background Music speaker) for my Grand Daughter out of spare MDF and aluminum leftovers, junkbox speakers (boombox grade) and some TDA2003 which are getting VERY long on the tooth he he.
Power supply is a 12V 2A ex-Router wall wart, every element used here saved from the corner trash can destiny.
And this is the "chassis/heatsink/front panel"
Suffering from the typical Tech/DIYer OCD, "I never junk anything",hate landfills with a passion, but try to repurpose stuff, and in general turn everything left over into some kind of mini (sometimes not that "mini") sound reproducer, which I later gift to friends and Family or donate to some School or Church.
They are usually welcome 🙂
What a chore!!!
I Punch it.
Of course, have the needed presses and die sets, so only now and then use a drill, typically to add something to an already built amp which of course won´t fit in a 3 or 5 Ton mechanical press, but avoid that as the plague it is.
Just by chance, at this very moment I´m making a small 12V 16W powered cabinet (sporting a 6" ex roof mounted background Music speaker) for my Grand Daughter out of spare MDF and aluminum leftovers, junkbox speakers (boombox grade) and some TDA2003 which are getting VERY long on the tooth he he.
Power supply is a 12V 2A ex-Router wall wart, every element used here saved from the corner trash can destiny.
And this is the "chassis/heatsink/front panel"
Suffering from the typical Tech/DIYer OCD, "I never junk anything",hate landfills with a passion, but try to repurpose stuff, and in general turn everything left over into some kind of mini (sometimes not that "mini") sound reproducer, which I later gift to friends and Family or donate to some School or Church.
They are usually welcome 🙂
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Juan,
Being in a backward country, I use the English measurement system, so please bear with me.
Minimum punch diameter normally is 1.5 times the material thickness except of course for aluminum where it can be slightly less than material thickness.
So for 10mm or to me .4” rounded off for simpler math, the punch force would be .2” x .2” x 3.14 x .4” x 28,000 lbs (5052 alloy) = 1407 lbs. Actually within the force available from a small punch.
The back die should have additional clearance of 10-15% of the material thickness. So a 10mm punch would require an 11mm or so die.
Cost on a cheap stock punch and die would be around $60 because you would actually have to buy two pre-made sets, one 10mm and one 11mm.
My initial though was that punching was impractical for this project, turns out my “feel” was wrong as long as all holes are larger than 10mm and less than about 26mm. (Assuming a 5 ton hand punch limit.)
Although for tooling costs drilling is cheaper, but much slower.
My CNC punch in theory can do 200 holes a minute. Actually slower as the material does have to be repositioned between punches. Tooling costs for such a setup today is around $250,000, but the more modern CNC punches can do 600 holes per minute.
An important tip for those viewing such a machine in use, don’t get too close because as it moves the sheet of metal if the edge can reach you it might just cut you in half!
Being in a backward country, I use the English measurement system, so please bear with me.
Minimum punch diameter normally is 1.5 times the material thickness except of course for aluminum where it can be slightly less than material thickness.
So for 10mm or to me .4” rounded off for simpler math, the punch force would be .2” x .2” x 3.14 x .4” x 28,000 lbs (5052 alloy) = 1407 lbs. Actually within the force available from a small punch.
The back die should have additional clearance of 10-15% of the material thickness. So a 10mm punch would require an 11mm or so die.
Cost on a cheap stock punch and die would be around $60 because you would actually have to buy two pre-made sets, one 10mm and one 11mm.
My initial though was that punching was impractical for this project, turns out my “feel” was wrong as long as all holes are larger than 10mm and less than about 26mm. (Assuming a 5 ton hand punch limit.)
Although for tooling costs drilling is cheaper, but much slower.
My CNC punch in theory can do 200 holes a minute. Actually slower as the material does have to be repositioned between punches. Tooling costs for such a setup today is around $250,000, but the more modern CNC punches can do 600 holes per minute.
An important tip for those viewing such a machine in use, don’t get too close because as it moves the sheet of metal if the edge can reach you it might just cut you in half!
With 600 punches a minute, perhaps they're relying on the noise to keep people at a safe distance. I generally use a vise or center lathe as a press.
Thanks for a real world view 🙂 and no problem with Imperial measures, per sheer necessity I and everybody else in Argentina HAD to be "bilingual" or else.
Only difference with U.S. members is that we started with British measurements in the 19th Century, basically because "that´s what was in use", the Industrial Revolution and so original norms developed there (our screw threads are typically B.S, even today, at least at the corner hardware store level) but since WW2 we fully adopted European metric, in fact German DIN with little cosmetic changes.
Remember we were "nazis" 🤣
What never ever caught up here is the wild "American" thread scale, and we have to check those numbers whenever they appear.
Oh well.
And thanks for you contribution 🙂
I have a third punch, 12 ton WIDE mouth for full Mixer panels, but avoid using it unless absolutely needed, it handles XLR and tube socket holes, and I have it on the floor, I or some employee have to kneel to use it, not kidding.
A large CNC such as yours is completely out of reality for me given the steady but smallish Guitar Amp market I move in, so when something is needed in quantity, say 50 Marshalish 3 Novals + 2 Octals + , say, 20 pot/jack/switch holes are needed, I rent shop time (in this case big wheel mechanical presses) at some small metallurgical shop (typically aftermarket or "second brand") car parts suppliers, who are well equipped to do the job but small enough to "listen" to me.
Contrary to what everybody expects, I never have chassis made at some specialized "chassis shop", they want to earn more than me!!! ....crazy.
My Guitar amp and pedal maker colleagues on one side diss me (politely) for my simplistic designs and on the other side bitterly cry because over the counter Chinese product price is way lower than their raw parts cost.
This year and a half Covid quarantine has been DEADLY, 80% or more closed shop for good.
Oh well.
Only difference with U.S. members is that we started with British measurements in the 19th Century, basically because "that´s what was in use", the Industrial Revolution and so original norms developed there (our screw threads are typically B.S, even today, at least at the corner hardware store level) but since WW2 we fully adopted European metric, in fact German DIN with little cosmetic changes.
Remember we were "nazis" 🤣
What never ever caught up here is the wild "American" thread scale, and we have to check those numbers whenever they appear.
Oh well.
And thanks for you contribution 🙂
I have a third punch, 12 ton WIDE mouth for full Mixer panels, but avoid using it unless absolutely needed, it handles XLR and tube socket holes, and I have it on the floor, I or some employee have to kneel to use it, not kidding.
A large CNC such as yours is completely out of reality for me given the steady but smallish Guitar Amp market I move in, so when something is needed in quantity, say 50 Marshalish 3 Novals + 2 Octals + , say, 20 pot/jack/switch holes are needed, I rent shop time (in this case big wheel mechanical presses) at some small metallurgical shop (typically aftermarket or "second brand") car parts suppliers, who are well equipped to do the job but small enough to "listen" to me.
Contrary to what everybody expects, I never have chassis made at some specialized "chassis shop", they want to earn more than me!!! ....crazy.
My Guitar amp and pedal maker colleagues on one side diss me (politely) for my simplistic designs and on the other side bitterly cry because over the counter Chinese product price is way lower than their raw parts cost.
This year and a half Covid quarantine has been DEADLY, 80% or more closed shop for good.
Oh well.
Juan,
One of my late friends was a German sound recording engineer. Previously he was a U boat captain who just after the war ended up in Argentina. From there he got a job with RCA in Brazil. From there he came to a movie production house here in Pittsburgh.
Interestingly his employers were Jewish.
He had built a classic recording studio with movable panels to adjust the amount of natural reverb. All the gear was European, AKG, Sennheiser, Telefunken, etc.
As to his Naval credentials, he still had the long shaggy hair and perhaps did not bath as much as most!
A nice guy and very dedicate to audio.
One other mutual friend also of German ancestry and audio recording, did not know the history. After I mentioned it to him, he considered taking our U boat friend out drinking and seeing if he could get any more interesting information. I always wondered who else might have been on that last trip from Germany to Argentina!
One of my late friends was a German sound recording engineer. Previously he was a U boat captain who just after the war ended up in Argentina. From there he got a job with RCA in Brazil. From there he came to a movie production house here in Pittsburgh.
Interestingly his employers were Jewish.
He had built a classic recording studio with movable panels to adjust the amount of natural reverb. All the gear was European, AKG, Sennheiser, Telefunken, etc.
As to his Naval credentials, he still had the long shaggy hair and perhaps did not bath as much as most!
A nice guy and very dedicate to audio.
One other mutual friend also of German ancestry and audio recording, did not know the history. After I mentioned it to him, he considered taking our U boat friend out drinking and seeing if he could get any more interesting information. I always wondered who else might have been on that last trip from Germany to Argentina!
Looky here!
Drill press, lots of oil, with cobalt and stepped bits did the job. Stepped bits ended up being the star of the show.
Thank you all for teaching me
Drill press, lots of oil, with cobalt and stepped bits did the job. Stepped bits ended up being the star of the show.
Thank you all for teaching me
A-9 aluminum cutting fluid is quite excellent. I've never had issues drilling through 10 mm aluminum on a drill press.
Tom
Tom
Congratulations.
Consider a clear lacquer to protect the finish, easier than getting it anodized.
Consider a clear lacquer to protect the finish, easier than getting it anodized.
Nothing better than pig fat has been invented for threading aluminum or dural 🙂
I cut blind threads in a big radiator, about 100 holes (blind) 2 cm deep (with pig fat) - didn't break any taps in the end.
I cut blind threads in a big radiator, about 100 holes (blind) 2 cm deep (with pig fat) - didn't break any taps in the end.
Also known as lard...
Taboo here in India.
And most Muslim and oddly enough Jewish countries.
In warm climates, it rots, and can cause sicknesses. That is another issue.
In a machine, particularly where a coolant pump is used, we must have a cutting fluid that can be pumped, not possible with pig fat.
As an aside, in England beef was hung for 3 days after slaughter, to allow the meat to rot by bacterial action, before it could be eaten.
At 15 Celsius, you can do it, at 40 here, it would be a stinking mess by evening of the first day. Not practical here.
Taboo here in India.
And most Muslim and oddly enough Jewish countries.
In warm climates, it rots, and can cause sicknesses. That is another issue.
In a machine, particularly where a coolant pump is used, we must have a cutting fluid that can be pumped, not possible with pig fat.
As an aside, in England beef was hung for 3 days after slaughter, to allow the meat to rot by bacterial action, before it could be eaten.
At 15 Celsius, you can do it, at 40 here, it would be a stinking mess by evening of the first day. Not practical here.
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