What's the secret to drilling through 1/4" angle iron?

[zzvyb6]

I drill 5/16 holes in angle iron windmill tower legs all the time. Even while they are erected and I am standing on the horizontal braces using my 18V Milwaukee hand drill. Often I can use a hand operated punch to do the job. Look up a Pexto or Roper Whitney on ebay.

As for drill bits: good, fast, cheap: You can only pick 2 of these options.

 

[deezler]

To clarify, I am drilling holes in the sides of a trailer so I can not use a drill press. I have to drill horizontally so any type of cutting fluid will run out of the holes rapidly. I have some new cobalt drill bits I am planning on using.

I can use either a 110v Hitachi variable speed drill or an 18v Craftsman on hi or lo speed. Is a continuous water spray any good as a cooler/lubricant, or a heavy oil or do I really need a specialty cutting fluid?

Maybe a good time to invest in a 1/2" chuck t-handle 600rpm corded drill, eh? It'll be your best friend for all the heavy duty drilling jobs and take all the pounding you can give it. Great for mixing mortar/grout/mud, etc, too.

Oh and do still apply some cutting fluid periodically even if drilling horizontal. It will help tremendously. You don't need a puddle of it to reap the benefits - even a thin film will still help a lot.

 

[Leejohn]

Look at this!!!! http://www.fnal.gov/pub/takefive/pdfs/Drill_Press_Speed_Chart.pdf

 

[Deere Dude]

Oil will run out of a hole if drilling from the side so just squirt a little on the drill bit a few times. That works.
For 40 holes like that just get some quality bits and possibly predrill with an 1/8" bit. I have some gold ones from Menards or Lowes and they really are crap. The kind I like are the plain black ones hanging and sold separately. I think they are High Speed Steel.

 

[MossRoad]

I have to drill 40 quarter inch holes through 1/4" angle iron with a hand drill. I've tried most of the different drill bits that Home Depot sells and they usually get too dull to drill after 2 holes.

Is there a better drill bit I can buy or am I doing something wrong in the way I am drilling?

Punch the hole locations first with a center punch so the drill doesn't wander.

Drill a 1/16" pilot hole. Its very easy. Go slow so you don't break the bit. Use cutting oil on the bit. Stop about 1/2 way through and squirt some more on the bit.

Enlarge it to 1/8".

Enlarge it again to 1/4".

You should be able to cut 40 holes with one 1/8" and one 1/4" bit but you'll probably break a couple 1/16 as you tend to get cocky and push too hard.

Once you drill a few 1/16" holes, you may feel confident enough to start with 1/8" and skip the smaller bit.

Just take your time.

Here's a link to all the bits you'd need for $20 with free shipping.
FREE SHIPPING — Ironton Titanium Drill Bit Set — 63-Pc. | Titanium Drill Bits| Northern Tool + Equipment

 

[kenmac]

Don't know about the slow part.. Most bits I buy are high speed drill bits.. Quality bits are hard to find.. Cobalt bits are better ,but are harder to sharpen once they dull..1/4 '' bit isn't that large of a bit.. You should do fine drilling that many holes without having to sharpen the bit.. The problem is finding a quality bit.. I usually buy/order from a machine shop supply company.. They usually have better quality bits

 

[Sodo]

Moss you will need all 18 1/16" bits to drill 40 pilot holes horizontally. I would try 3/32" pilot holes minimum, see if 3/32 survives or 1/8, then go to 1/4". Note: that's 80 holes. You CAN lube a horizontal drill bit. If you go to Home Depot and buy a Milwaukie 1/4" bit I would expect it to drill more than 40 holes in normal angle iron and still be sharp. Something is way wrong if its dull in 2 holes. The 1/8 bit can spin fast. The 1/4" bit should turn about half the speed of the 1/8.

Tallyho8 you should probably tip that trailer up - block the wheel up a foot or two & save your back.

Easiest and fastest way to drill horizontal holes is with the annular type bits such as Blair / Hougen. They are like holesaws, they are fast because they don't have to turn the whole plug into chips. Great for battery drills, they cut faster and with less power.

Among the best $63 I've spent on bits was this kit by Blair, but this kit doesn't have 1/4". It has 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, and 3/4. Maybe you can use 5/16" holes for your project.

 

[MossRoad]

Moss you will need all 18 1/16" bits to drill 40 pilot holes horizontally. I would try 3/32" pilot holes minimum, see if 3/32 survives or 1/8, then go to 1/4". Note: that's 80 holes. You CAN lube a horizontal drill bit. If you go to Home Depot and buy a Milwaukie 1/4" bit I would expect it to drill more than 40 holes in normal angle iron and still be sharp. Something is way wrong if its dull in 2 holes. The 1/8 bit can spin fast. The 1/4" bit should turn about half the speed of the 1/8.

Tallyho8 you should probably tip that trailer up - block the wheel up a foot or two & save your back.

Easiest and fastest way to drill horizontal holes is with the annular type bits such as Blair / Hougen. They are like holesaws, they are fast because they don't have to turn the whole plug into chips. Great for battery drills, they cut faster and with less power.

Among the best $63 I've spent on bits was this kit by Blair, but this kit doesn't have 1/4". It has 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, and 3/4. Maybe you can use 5/16" holes for your project.

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I've drilled and tapped thousands of small holes in heavy steel at odd angles over my years at my employer retrofitting old and installing new machinery. I was fortunate to have access to good drills, magnetic drill presses, good bits, etc....

The OP wants a simple, fast solution for a hand-held drill. I gave him one for twenty bucks and he can even get the hole size he wants. :laughing:

I agree with you that your solution is better if he wants to spend the money. And better bits are just, well, better. :thumbsup: But they cost more. No free lunch.

 

[oosik]

What ever you end up doing - I do not envy you drilling 40 holes horizontally with a hand drill. Just the thought makes my wrist ache.

 

[bindian]

I agree with Jigbuilder. All my life I have worked with pneumatic drills on aircraft. All that and 5 years experience rebuilding helicopters and modifying steel rebuild jigs taught me to drill everything horizontal with a pneumatic drill that you can control the trigger to the speed you need. I use Boelube (a waxy lube made by Boeing Aircraft) and can drill 40 pilot holes in 1/4 inch steel with one #40 (1/16th) drill bit without center punching. Then I step up to #10 bit, then a 1/4 inch bit. I drill (using Boelube) up to 1 & 1/8 inch holes at home with my geared electric drill, after step drilling holes up to 1/2 inch with my Mikita drill. Use what you are comfortable with. Go slow.........and keep it lubed, which helps the bits stay cooler and sharper longer. Also, small bits need to be pulled out of deep holes every so often to clear the hole. If not, you can break a #40 bit in a heartbeat.
Good luck. I would love to own a magnetic drill!
hugs, Brandi