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

[MossRoad]

I finished my trailer today. With some re-engineering, I found that using 20 5/16" bolts would be just about as strong as using 40 1/4" bolts so I used the 5/16 ones. I did not drill a pilot hole.

I used a Dewalt cobalt pilot point 5/16 drill bit which was still just as sharp on the last hole as on the first. I had used some Dewalt titanium bits in the past and this bit put those to shame. I used my 18 volt Craftsman drill on the low range. I don't know exactly what speed it was, but it was probably about 300 rpm. Following advice that I got in this thread, I put as much pressure on the drill as I could and it drilled through the 1/4" angle iron making long spirals instead of little chips.

I did not use cutting fluid or coolant because at this low speed and with it cutting so fast, I could touch the bit after I drilled the hole and it wasn't even hot.

Now I understand how I burned up so many drill bits in the past by going at a high speed and not using much pressure with a hand drill on jobs like this.

Thanks to everyone who gave advice and I just wanted to let everyone know what worked best for me. This job turned out to be much easier than I had thought it would be. :thumbsup:

What? No one handed drilling while taking a video with the other? I'm highly disappointed.

:laughing:

 

[GPintheMitten]

I see you got it done. Good for you.

For future thread readers, for occasional home shop use, you can't beat a small benchtop drill press compared to hand drilling. Something like this:

Northern Industrial Tools Benchtop Mini Drill Press — 5 Speed, 1/3 HP | Drill Presses| Northern Tool + Equipment

 

[k0ua]

I read an article a long time ago when I was a young man that said that a good drillpress was one of the first things you should buy for your shop. The wife and I scrimped and saved and we bought a nice 15 inch floor stand model. I have never regretted purchasing it. I have bought many tools since, but the drillpress has been one that I probably use the most. Just bite the bullet and get a good one. It wouldn't have helped in the OP's situation but in general they are so useful.

 

[bigtiller]

I use mine on just about every project I do. I am seriously thinking of buying a second one. If one is good, wouldn't two be better?

 

[4570Man]

Look for a used milling machine. Going from a drill press to a milling machine is like going from a hand drill to a drill press.

 

[bigtiller]

I have been waiting for one to come my way but they are about as rare as hens teeth.

 

[the old grind]

I have been waiting for one to come my way but they are about as rare as hens teeth around here.

Fixed that for ya.

If you're serious, look for a used mill in KC, Chicago, or Minneapolis ('Bridgie clone' or 'mini' thereof). Big markets there, if sparse picking at times. (If you can't afford to haul it, you might can't afford to buy it.) 3-Phase power usually requires a rotary Phase converter or VFD but cost may be offset somewhat by possible lower price of smaller 3PH machines.

btw, I paid more than 4x for my ZTR mower ($5k vs ~$1K & very lucky) than for the used knee mill. Ya gotta shop hard for a good deal on a good machine when retirees like me are after 'em too.

Hope the OP doesn't mind the side-track, ... since he's done. ....

 

[BigTruckMan]

I do professional steel fabrication, and I use high quality HSS steel bits on my mill/drill .

.I sell in my opinion some of the best drill bits there are . A 1/4'' drill bit is about $5 ,but it will last forever. These are the only kind of bits that I use . I have done hundreds of holes with my bits.
It also helps if you put some pressure on the drill ,and use some cutting fluid. Also make sure that you keep your bit strait.
Also,I never do pilot holes unless I'm drilling 3/4'' or bigger holes. I would recommend going on ebay or to a local steel fabrication shop and see if they have any high quality bits ,or you can contact me and order one from me.

 

[Dwayne Oxford]

1st time I saw a Dewalt pilot point bit used it was in an oversped, over pressured hand drill and bending every which way. Got me some quick. I drill a hole in the welding magnets and rig a low pressure air blow to cool the bit which allows you to spin'er WAY faster. If you wanna get real fancy you can buy a mister

 

[LD1]

A mill is certainly a step up from the average homeowner drill press. But IMO it is no replacement for an actual drill press. For most of what us guys do here, yep a mill would be a lot handier and can handle most of out drilling needs. But when using larger bits, Like 1"+ and drilling through thicker metals, a large drill press is alot better than a small mill.