Drilling Holes

[Too_Many_Tools]

Hi,

Awhile back I built a table using a combination of channel and angle iron of 1/4" and 3/8" thickness steel. I found that when I needed to drill holes up to 1" diameter, my drill press was able to do it but just barely.

What would you recommend to drill holes the next time I need to do this?

Thanks

TMT

[asad]

hole saw, go slow and use lots of coolant.

Or...step up the drill size...start with 1/4", then 1/2", then 3/4", then 1".

Asad

[John1]

Which drill press do u have, chuck size and hp??

When u say it would barely do, do u mean it would "strain" or there was a problem with the bit?

One inch is a a pretty good size hole.
John1

Have been a machinist for 15 yrs and may be able to help!!

[peterabout]

Do you have access to a milling machine? These machines are better suited for larger diameter holes.

[Too_Many_Tools]

The drill press I had was a 1/2 hp with a 1/2" chuck and I was using silver demming drills that go from 1/2" to 1". The drills slipped in the chuck, the belt slipped on the drill press and with new drill bits the going was very slow to say the least. I did step drill the holes going from smaller to larger bits but it was an ordeal.

Since I have a number of heavy structural steel projects in the offering, I am looking for a better way to drill holes up to 1". I have seen mag drills but they are very expensive. The best solution may be to rent a mag drill for the holes.

I do have a milling machine but the steel components are too bulky and awkward to use the mill.

TMT

Which drill press do u have, chuck size and hp??

When u say it would barely do, do u mean it would "strain" or there was a problem with the bit?

One inch is a a pretty good size hole.
John1

Have been a machinist for 15 yrs and may be able to help!!

[gfunkatoa]

Hole saw, patience, and lots of coolant/cutting oil. And don't skimp on cheap hole saws. I've seen people curse hole saws and come to find out they were using a hole saw that is ten years old and rusty as ****. Some evev had teeth missing. A good quality new hole saw will cut 3/8 like butter. Even with a hand drill, but be careful.

[bobad]

Hi,

Awhile back I built a table using a combination of channel and angle iron of 1/4" and 3/8" thickness steel. I found that when I needed to drill holes up to 1" diameter, my drill press was able to do it but just barely. What would you recommend to drill holes the next time I need to do this? Thanks TMT

Regardless of the tool you use for cutting holes that big, patience is the best tool of all.

1" holes are a challenge for anything but the biggest and heaviest of machinery. I believe I would look for a good bi-metal hole saw, and be ready for a mess. They need lots of oil to keep from burning up. One chipped tooth can imbed in the metal and instantly ruin the rest of the teeth, so patience is the word.

[enlpck]

Well, a mag drill IS the best way to go if you can afford it, but the old way was a chain drill-you chained the drill to the work.

You can make a general purpose tool from suitably sized drill press. Take off the table, and you can clamp the base to your work, chain it down, tack-weld grasshoppers or staco's on to hold it, etc. Or, remove the base and make custom bases for different jobs-a piece of channel for radial holes on cylindrical shells, etc. I would recomment a press that DOESN"T have belt speed change

The drill press I had was a 1/2 hp with a 1/2" chuck and I was using silver demming drills that go from 1/2" to 1". The drills slipped in the chuck, the belt slipped on the drill press and with new drill bits the going was very slow to say the least. I did step drill the holes going from smaller to larger bits but it was an ordeal.

Since I have a number of heavy structural steel projects in the offering, I am looking for a better way to drill holes up to 1". I have seen mag drills but they are very expensive. The best solution may be to rent a mag drill for the holes.

I do have a milling machine but the steel components are too bulky and awkward to use the mill.

TMT

[TJButler]

enlpck:
I am REALLY interested in what you are talking about. Please excuse my inexperience, but what is a grasshopper or a staco?

I have been a home fabricator for about a year now and am interested in different set up and fit up tricks and hints. I love building things. I have built up a collection of weld nuts and weld tabs, etc. from the fence supply place and am gradually building my skills.

I have purchased a Milwaukee Compact Mag Drill kit(1 1/2" max) and just played with it for the first time two nights ago. I bought the Jancy shallow annular cutter set(1/2" > 1 1/16"). I drilled a 1/2" hole in some 3/8" in plate and I said, "Whoa, OMIGOSH that thing does some serious cutting".

I know the drill instructions say that is must be attached to at least 3/8" plate and I have been brainstorming about how I could build a fixture to use it as a portable drill press for various sized items out in the field.

I had drilled up to 1" with a bench top drill press and it did take some patience.

Thanks a lot!

[enlpck]

enlpck:
I am REALLY interested in what you are talking about. Please excuse my inexperience, but what is a grasshopper or a staco?

staco: toggle clamp for hold-down type jobs: search for "destaco clamp" A grasshopper is a weded on piece for going over a joint -- often half a c-clamp or an L-shape so you can drive wedges under it to hold or line parts. The destaco's are real handy.

A chain-on setup for going around large things can be made using standard chain binders. I highly reccommend attaching the chain to the tool-setup is easier and safety is greater.

Cripes... I'v been known to just bolt the drill press to the part through a conveinient hole....

I have been a home fabricator for about a year now and am interested in different set up and fit up tricks and hints. I love building things. I have built up a collection of weld nuts and weld tabs, etc. from the fence supply place and am gradually building my skills.

I have purchased a Milwaukee Compact Mag Drill kit(1 1/2" max) and just played with it for the first time two nights ago. I bought the Jancy shallow annular cutter set(1/2" > 1 1/16"). I drilled a 1/2" hole in some 3/8" in plate and I said, "Whoa, OMIGOSH that thing does some serious cutting".

The annulars kick butt. MUST be in a rigid set-up, tho, and must be kept cool.

I know the drill instructions say that is must be attached to at least 3/8" plate and I have been brainstorming about how I could build a fixture to use it as a portable drill press for various sized items out in the field.

I had drilled up to 1" with a bench top drill press and it did take some patience.

Thanks a lot!

[Rocky D]

...A grasshopper is a welded on piece for going over a joint -- often half a c-clamp or an L-shape so you can drive wedges under it to hold or line parts....

I've always called 'em "dogs", as an ironworker....I think "dogs" to a machinist, is something else. "Grasshopper" is someone who can't quite walk on the rice paper without tearing it.

[richard b]

Rota- broach-------uses annular cutters..............1 in. hole is a snap........most structural shops large and small have them..........got any friends in the steel business?
RB

[joejrwelds]

Jancy, Hougen, Nitto and a few more have the slugger type bit. A 1" bit might be $60 verses $20 for a S&D 1/2" shank twist drill, but the production from the slugger is huge. For example I had a job with 50 1-1/16" holes in 1/2" steel. After it was all layed out, the drilling from start to finish was just over 1 hour, that is just a little bit more than 1 minute a hole. To me time is money so this type of drill can quickly pay for itself in commercial applications. I use lots of water soluable cutting fluid in a janitor's trigger pump bottle and the bits keep an edge a long time.

A by product of the above 50 holes was a trash can full of swarf, it was the coursest looking steel wool i've ever seen.

[LarryL]

I found this "Super Drill" through a web search. It appears to work like a metal lathe's boring bar and may be the ticket for those of you who have small drill presses. I don't have any personal experience using one. I was searching for an unusual rotary bit that I found last year but haven't been successful so far.

http://www.superdrill.com/index.html

Larry

[MM251]

Check out your drill press.

Does the 1/2" jacobs chuck come out? Mine has a #2 Morse taper on the quill that the chuck fits into. If yours does, get some bits with the morse tapers on them and skip the chuck altogether.

Next idea - If you do have the morse taper feature there should be a slot in your quill, (the shaft that goes up and down as you drill). With the slot you use a drift to knock out the chuck.
Now with that feature you may also look into four flute drills. They are hard to find and they aren't used to start holes. They make existing smaller holes bigger. The value of four flutes is that they make perfectly round holes. Beautifully round holes. They are like a ream and drill in one tool. You might find them at auctions of machine shop equipment. They would go cheap as most people don't know what to do with them. Try one and you'll love them.

The pix should make all this a whole lot easier to follow.

Hey- slowest possible speed when doing the big holes. Slow feed. Make chips. Lots of lube. CLAMP IT DOWN.

Good Luck