Tips for drilling Large Holes

[Jaac]

Originally Posted by Bonsai

Wow. I dont think this is very safe advice for drilling metal of any kind.

Only for aluminum recommend it. And only with some lubricant.

Originally Posted by Bonsai

I really would suggest you follow the advice further up this thread. To summarize:-

I'm always willing to learn.

Originally Posted by Bonsai

1. use a drill press and make sure your work is clamped well clamped to the drill press work surface or.
2. make sure your work is well clamped if using a hand drill

All my drilling activities are done with a drill press and if possible clamped.

Originally Posted by Bonsai

3. start with a small drill diameter and work upwards with bigger drill bits to your final hole diameter.

This is time consuming activity and with not much spare time this can be skipped with my advice with the point welding drill. You only chop off slices of aluminum and because you drill with low speed it is a very controlled way of drilling. Also you don't end up with triangular holes.

Originally Posted by Bonsai

4. Use slowest drill speed - especially for aluminium
5. Use some cutting fluid - it works and makes a big difference (some 3-in -1 oil also works well)

As always

Originally Posted by Bonsai

6. Best solution: Drill press and a stepped cutter. Second best solution: hand drill and a stepped cutter.

This only applies to sheets thinner then the steps on your stpped drill.

[ChrisA]

This only applies to sheets thinner then the steps on your stpped drill.

Recently I was able to drill 1/4 inch thick with step drill by drilling from both sides. Worked better then I thought it would, nice clean round hole. Careful alignment is required.

[454Casull]

I would rank the methods like this:

1. hole punch (sheet metal)
2. end mill (for any material and almost any thickness)
3. stepped drill bit (sheet metal)
4. twist drill bit (only for aluminum or wood)

I've never used the spade bits with the edges.

[Geek]

Originally Posted by 454Casull

4. twist drill bit (only for aluminum or wood)

Unless you have cobalt bits and a drill press... then steel drilling is OK
(I have scars on my hand that say WHY you do NOT use a hand drill when drilling steel)

Steel Hammond/Bud/etc. chassis... titanium coated are OK, but do use the cheap ones, cause the expensive ones will wear out just as fast as the cheap ones and you don't feel as guilty when you dump them in the bin

Cheers!

[MJL21193]

Originally Posted by Geek

Unless you have cobalt bits and a drill press... then steel drilling is OK
(I have scars on my hand that say WHY you do NOT use a hand drill when drilling steel)

Steel Hammond/Bud/etc. chassis... titanium coated are OK, but do use the cheap ones, cause the expensive ones will wear out just as fast as the cheap ones and you don't feel as guilty when you dump them in the bin

Cheers!

I drill steel every day with twist drill in a hand drill...I just don't do silly things like drill through my hand or try to use my hand (or fingers) to clamp the work down. Some common sense helps.

Cheap bits get duller quicker and break more easily. Some cheap bits are worth buying and others are not. Here in Canada, Canadian Tire (store) puts the Makita brand bit index on sale occasionally for $4. It has 1/16 to 1/4 and is well worth the money.
For bits above 1/4" do yourself a favour, buy better quality ones. The corners of the cutting edges will chip off on the cheap ones really fast and unless you can sharpen it, you are SOL and out the bucks for the bit.

[Geek]

Originally Posted by MJL21193

I drill steel every day with twist drill in a hand drill...I just don't do silly things like drill through my hand or try to use my hand (or fingers) to clamp the work down. Some common sense helps.

http://www.diyaudio.com/forums/equipment-tools/152852-work-tools-explained.html#post1940481


I actually compared three boxes each of titanium bits from CanTire and the dollar-plus store.... both lasted the same time on aluminum/steel cabinets.

If it wasn't for the receipt, you couldn't tell the boxes apart out of their packages.

Cheers!

[zeonrider]

The best drilling bit I, ever used:



Min. size 8mm & Max size 30mm.

Regards zeoN_Rider

[MJL21193]

Originally Posted by Geek

I actually compared three boxes each of titanium bits from CanTire and the dollar-plus store.... both lasted the same time on aluminum/steel cabinets.

If it wasn't for the receipt, you couldn't tell the boxes apart out of their packages.

I could probably tell the difference

Canadian Tire sells mostly junk now, not much better than a dollar store but they have varying quality.
As for the dollar stores, I don't go to them and I certainly wouldn't buy any kind of tool in there...

[MJL21193]

Originally Posted by zeonrider

The best drilling bit I, ever used:

Step drills are great (if they are good quality) for thin aluminum, steel and even for thicker metal, like ChrisA mentioned above. They cut less aggressively and that reduces the tendency "grab" the work.
I use Milwaukee step drills which are fairly priced and for a lower cost one there is Samona which is pretty good and nearly half the cost of the Milwaukee.

[zeonrider]

Believe or not The best Tool.

Don't use with hand machine, only with Drill Press!

Regards zeoN_Rider