To step drill or not?

[gm280]

Just wondering on everyone's ideas and opinions. Is it better to step drill solid steel bar to 5/8" or just use a 5/8" drill bit and drill the bar steel from the start. I am going to drill a 5/8" hole in a solid 1" square bar steel. I have drilled 3/8" and 1/2" holes in the same bar stock straight from the start and that seemed to work pretty good with oil and removing the drill to clear chips. Just wondering what others think... Oh, this is on a floor model drill press, not hand drilling. What say you and why? :decision:

 

[WIMUSKY]

Step drilling would be the easiest, but since you have a drill press, send it!

 

[alldodge]

Interested my self.
I cut a trailer hitch shorter and drilled a new hole and burned up 2 bits doing it. This was standard 2 inch hollow hitch, so two 1/4 inch drill through's

 

[GA_Boater]

Quality drill bits, oil and a drill press - Go for it. If you see smoke, stop, let it cool and use less pressure. Maybe sharpen the bit or switch to another bit.

 

[Scott Danforth]

I have always step drilled..... mainly because that is what I was taught from when I was knee-high to a spark plug.

drilling by hand
normally, center punch the hole
pilot drill is usually an 1/8"
then 1/8" increments to final dimension

drilling on drill press without clamping (allowing drill vice to slide around)
center punch the hole
pilot drill of 3/16" or 1/4"
then 3/16" increments

drilling on a drill press or mill, with work clamped and using x/y table
just drill...step drill in 1/2" increments if you're hogging holes
use a roto-broach if you have big holes.

In your case, the steps you took are fine.

 

[dwco5051]

If I am using the drill press I usually would just go for it. Keep the speed about 800 rpm and watch the chip color. If they are starting to turn solid blue let off a little pressure.

 

[gm280]

I NOW have a cross slide cast iron vice so I can center the part dead on. However I will use a center bit first. But since I did drill with both 3/8" and 1/2" through holes in the same material without any issues, other then the hand-held vice spinning around and smashing my hand as it broke through the 1/2" hole, I managed to drill straight through without a step drill effort.

But now I have the cross-slide vice solidly bolted to the cast iron table at three locations. And I can adjust the setup and keep my hands away from the spinning action as well. I still will use oil and stop for chip clearing, but I think I will go for it without steps. If I screw it up, I have more material...

Thanks for everyone's suggestions. Pretty much mimics what I was thinking. I initially had in mind to chuck up the part in the metal lathe and drill a 1/2" hole and then use a boring bar cuter to finish up to the proper size. BUT, pretty hard to chuck up a square 1" bar stock in a three jaw chuck. Oh yes, it can be done, but with more effort then I want to try. One day I will own a independent four jaw chuck and then it would be a breeze to do that method. So drill press it is...

I actually tried to ask that same question on the internet. But as soon as it seen the "step drill" part of the question, all it did was post step drill bits to buy. Never any answers to what I was asking. Don't you love the "smart" internet?

Thanks to all respondents. I really do appreciate your opinions...

 

[GA_Boater]

Don't you love the "smart" internet?

Where did you find it? How many said to get a set of these?

 

[dingbat]

Welder and Machinist by trade....managed the weld and machine shops for a number of years.

All depends on how accurate the part needs to be...

A drill will "walk" (off location) elongate (get bigger) and "run out" (out of perpendicular) unless the part is held securely in a vise and step drilled as prescribed by composition.

 

[Scott Danforth]

I actually tried to ask that same question on the internet. But as soon as it seen the "step drill" part of the question, all it did was post step drill bits to buy. Never any answers to what I was asking. Don't you love the "smart" internet?

Thanks to all respondents. I really do appreciate your opinions...

not only can you no longer do a decent "google" search, the boolean search function no longer works. as a search engine, Google used to be the best, now it simply sucks. google has gone full-on advertising just like farcebook.

 

[alldodge]

WebCrawler still works but it to has adds, but not as bad as google

 

[gm280]

Welder and Machinist by trade....managed the weld and machine shops for a number of years.

All depends on how accurate the part needs to be...

A drill will "walk" (off location) elongate (get bigger) and "run out" (out of perpendicular) unless the part is held securely in a vise and step drilled as prescribed by composition.

That is true. However, I DID learn a valuable lesson with the 1/2" hole drilling. Yes, I was drilling with the 1" bar stock tightened in a machinist vice, but it was not bolted in place on the drill press. I was merely holding it by hand flat against the press plate, which has served me well until the break through out the other side. As typical, the downward pressure made the breakthrough catch the metal and twist that vice out of my hand and spun it around with enough force that it hit my hand pretty badly. I got one of those He-Man-Toe-Mas on my wrist and hand with about four or five cuts. Blood was leaking out of me and pain made my hand felt like it was crushed.

Lucky the blood stopped in short order and I decided to forego any doctor or hospital visit knowing the hours I would sit at either pace, and since I could move my hand and fingers without issues (but some pain). So the stinking cleaning up of the cuts and applying antibacterial ointment and ice packs was the rest of the day's regiment.

So lesson learned the hard was. Those are the lessons you never forget. However, this final 5/8" drilling is with the cross-slide vice bolted down like it should have been all along. Cutting corners is so painful isn't it... :faint2:

Oh, when I was talking about step drilling, I was actually talking about starting with say a 1/4" bit and then up-size about an 1/8" in size 'til I get to 5/8". Not the stepped drill bits we all are used to now...

 

[gm280]

Okay I thought you all would like a update and actually a closer to this question.

This morning, finally getting enough time to actually drill the bar, I used a typical center punch and then a center drill, the type typically used on a lathe. Then I chucked up the 5/8" bit and got the oil and decided to go for it. At first there was a lot of vibration until the drill actually got well started. Then it was like cutting butter. I had to drill in the very end of the 1" square bar steel to a depth of about 1 1/2". Once it got started, the drill bit cut amazingly smooth AND fast with very little pressure. I stopped along the way to re-oil and clear chips and it was all over in a couple minutes without issue.

So the answer for this situation anyways was to go for it and get'r done. I looked all over for a 5/8" bit because all my drill sets stop at 1/2". Well the typical cost was ~ $15 dollars at best. I started searching the net for anything. I found a nice set of bits on Amazon that were from 1/2" to 1" in 1/16" steps. And they were also reduced shank to 1/2" diameter as well. And since their total cost was $30 dollars, I had to buy them. The reviews were very good, and that sold me!

Glad I did and so many projects that need large bits are now on the list... The drill press can handle them and I also think the chuck can handle up to 3/4" So being cut shank, no problems.

Thanks to all that provided their ideas and opinions. Those ideas and opinion are more helpful then some think. I would proved pictures, but I am sure everyone has seen a hole drilled in the end of bar stock before...

Have a wonderful safe day!