trying to drill into my hs why do is it so hard

You can buy hardened bits from the store. They have more of a driver end on them rather than just a typical looking drill bit. Still fit all drills.

They are made to drill metal up to 3 times faster than a normal bit. Used them all day by hand and didn't break one

Sutton supa bits.
 

orbo

Well-Known Member
If the HS is aluminum then its probably because the bit is getting clogged up with metal. Drill a little, clean the bit. Drill a little, clean the bit....and so on. This is assuming its aluminum.

When I worked construction we used to have problems with aluminum clogging up bits, wire wheels, grinder discs...etc. It was because they always clogged up with material.
 

stardustsailor

Well-Known Member
I use a bench drill @ 620rpm.No lubricant of any kind and ordinary High Speed Steel drill bits (HSS) and usually I start easy with pressure and keep increasing pressure until the hole is done ...
Never had an issue .But the heat sinks I'm using are made of soft 1060 or 1050 alloys
https://en.wikipedia.org/wiki/1060_aluminium_alloy
( I do not think that you can find easily that kind of heat sinks ,BTW ....Only custom made,probably ... )

Anodising is not a real issue ,'cause we're talking about 0.5-150 microns of thickness ...

I'm guessing that:

1) either your heat sink is made of some kind of tough Al alloy ( Families 60xx-70xx ) and/or
it is hardened enough.. ( > H5 )

2 ) You're drilling at an angle ..(not perpendicular to heat sink surface ).
At a point the drill bit "bites" on aluminium and the bit breaks ...
 

Rrog

Well-Known Member
I agree on the increase in speed. Agree in the value of a drill press. I drilled out 100 holes for a big sink with a drill press. No lube. Piece of cake.

Anodization doesn't make it harder to drill as previously mentioned.

Use a punch to mark the hole
 

Jimdamick

Well-Known Member
thought it was the drill ...maybe its the lack of no oil.. i was doing light pressure and going little at a time ..also going back and forth
Do not wiggle the bit, that's a good way to snap it. Keep the drill at 90 degrees an push evenly , keeping the bit straight!! The larger the bit size the harder it is to break, so go to a 1/4 inch if you can, as snapping that in aluminum is very hard to do. You will not need cutting oil for aluminum, only steel.
 

stardustsailor

Well-Known Member
Inside the zip folder you will find a short vid ...

I used an old anodised heat sink ( Alloy 1060 ) and a HSS 4 mm drill bit ...
With my left hand i'm holding my lousy cell phone ,recording the vid ...
With my right hand I'm turning the lever ,lowering the bit towards the heat sink surface ..
Heat sink has a mass of ~ 2 lb and it isn't even clamped on to the bench drill ...
Thickness of surface being drilled is 10 mm .
piece of cake ...
 

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bicit

Well-Known Member
TiN coated drill bits and taps are great for aluminum. Consider investing in a cheap drill press from hf TOOLs they're good for this.

WD-40 for a cutting lube. Works great cleans up easy. I've seen others using propylene glycol for water soluble lube. Worked great when I had to drill 104 3.75" holes in .125" 5051 aluminum plate.

Never attempted to drill into a heatsink free hand before so I can't offer help there.
 

whitebb2727

Well-Known Member
If the HS is aluminum then its probably because the bit is getting clogged up with metal. Drill a little, clean the bit. Drill a little, clean the bit....and so on. This is assuming its aluminum.

When I worked construction we used to have problems with aluminum clogging up bits, wire wheels, grinder discs...etc. It was because they always clogged up with material.
Aluminium will spiral out of the hole if drilling fast enough. Were you using aluminium specific sanding disk and grinding wheels?

Using steel disk and wheels on aluminium is dangerous. It clogs and then the disk or wheel blows up from heat.
 

orbo

Well-Known Member
Aluminium will spiral out of the hole if drilling fast enough. Were you using aluminium specific sanding disk and grinding wheels?

Using steel disk and wheels on aluminium is dangerous. It clogs and then the disk or wheel blows up from heat.
No, the guy I worked for was a cheap bastard. He put ZERO stock in anything except scrap copper. Hand files are the worst for getting clogged up using them on aluminum.
 

john0000

Well-Known Member
i switched bits and went up in size so its not so flimsy ...now I'm doing a5/32 hoe and using #8 screws and I'm moving along now .thanks everyone
 

bicit

Well-Known Member
Aluminium will spiral out of the hole if drilling fast enough. Were you using aluminium specific sanding disk and grinding wheels?

Using steel disk and wheels on aluminium is dangerous. It clogs and then the disk or wheel blows up from heat.
Regular flapper wheels and stainless steel wire brushes are ideal for finishing aluminum. dont cross contaminate by usingyour tools on mulmultiple metals. Label the tools you use 'aluminum only' and only use those on aluminum. Especially if you ever have to weld on the aluminum, contaminates are the devil.
 
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whitebb2727

Well-Known Member
No, the guy I worked for was a cheap bastard. He put ZERO stock in anything except scrap copper. Hand files are the worst for getting clogged up using them on aluminum.
I was standing next to a guy using a table grinder with steel wheels grinding aluminium. It was louder than a 12 gauge when it exploded. Face shield saved him.

I had some leaf spring hangers break on a truck. I was using zip wheels and air compressor to cut the rivets out. Those cold pressed rivets on a truck frame are tough.

Anyways, I was using a friends setup and he didn't store the zip wheels right and moisture got to them. One exploded in my face at 10,000 rpm. I about pooped my britches. I had a face shield on.

I also hate it when people don't store welding rods right. I mean all it takes is an old fridge and a light bulb to keep them dry.
 
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