i've got months of drilling steel ahead of me...

[AJM]

it is very difficult work. We (me and another guy) are out on a swing stage drilling holes through 12 gauge galvanized steel .. basically it is 4 layers of galvanized 12 gauge per "stud" and we have hundreds of these things to drill. We have to make four 1" holes in each stud. It will take months to do.

our company gave us a 1" drill bit and basically said go to town.. we got 1.5 holes done in 4 hours, and ruined an expensive bit.

we brought our own bits and we are running small pilot holes (1/4" , then 1/2", then 1") .. this is much easier but it is still ridiculously hard work.

a plasma cutter would be great but the way the beams are formed, you could nto cut completely through with a plasma cutter because it wouldnt reach. the beams are like this.. each line is a layer of 12 gauge, a solid beam in the center with "caps" on the edges, and it is about 6" wide across:

[ || ]

so you cuold use a plasma to cut the outside edges , but wouldnt reach the interior .

i was also thinking of using an acetylene torch , but im not sure if it would reach the interior either.

would pre heating the metal with a torch make it easier to drill? i know we could cut throught the outside pieces with a torch but im not sure about the inside

thx for any advice

[tbone550]

Maybe try out an annular cutter of some sort rather than solid bits. I would not preheat the metal and then drill - you'll just ruin your bits immediately.

If there's room for slop in the holes, using a torch with a long specialty cutting tip may be workable if you can find one, but I hate to burn galvy if there's another way around it.

[nadogail]

Would a mag base drill work?

[LawsonWeldingLLC]

The problem with annular cutters u have to remove the slug before going on to the next hole, if there 12 guage and its all stacked upon each other i personally would run to the home depot or lowes and buy a 1inch punch for electrical work or a "stud punch" looks like bolt cutters with a punch in it i hate doing anything to galvanized that has anything to do with heat, my health is worth more than that to me.

[LawsonWeldingLLC]

http://www.gardnerbender.com/pdf/pro...ole_making.pdf

The other thing u might try if u are stuck with drilling them is step drill bits its amazing how quickly they will run through thinner metals.

[Boostinjdm]

1.5 holes in 4 hrs? What were you doing the rest of the time? I'd go with a handful of good hole saws and a special extension.

[SR20steve]

Mag drill and hole saw. Still time consuming but probably the best way to go with the galvi IMO.

[Pavinsteelman]

Small frame drill from Jancy or Hougen with 1" x1" annular cutters.

[Pavinsteelman]

Hyd punch see Gardener Bender on other post , Nitto Koekie has them too.

[DSW]

I thought about suggesting a punch also, but it looks like there is an air gap between the outter and inner plates that would make this impractical unless they were punched prior to assembly. You won't be able to get the two dies on the same piece of steel at the same time.

I'd vote for a mag drill and holesaw/anular cutter as my 1st choice, and then mag drill with twist bits/ step drills as a second choice. As mentioned you'll need to clear the slugs with an annular cutter or hole saw. I noticed recently Lowes has carbide holesaws in stock. I was thinking they'd make a good addition to my set for working in steel vs the standard bimetal ones.

[Bikespot]

Heating the metal to try and make it easier to drill is a bad idea. Your just adding more heat to the drill bit = bad. If the drill bit or cutting tool you use gets too hot it weak/dull the cutting edge.

I would try with a mag base and a hole saw. Mag base will give you rigid drilling , and be able to put alot more pressure on the drill. Dont run the hole saw speed too fast, 1" around 300rpm and if you can mix up some coolant. Will keep it sharp.

[Jack Olsen]

I think this is the key question, based on the progress you made:

What RPM is the drill you're using turning your bit at?

[taylorcraft1947]

AJM,

1.5 holes drilled in 4 hours? Drilling should not be that much work. Speaking from experience, it should take no more than 1 minute 30 seconds to drill a 1 inch hole through 3/8" structural steel using a good mag drill and a "centerless" cutter with coolant (I have done this 8 hours a day for weeks at a time). If one guy center-punches the holes as you go, you should be able to position and drill at least one hole every 3 minutes.
However, spindle speed, power, and proper technique are everything when it comes to drilling holes. This means that you need several drills and/or a variable speed drill if you are going to step drill the holes. A 1/4" drill should spin about 1500 rpm, a 1/2" drill should spin about 800 rpm, and a 1" drill should spin about 400 rpm. These speeds are approximate values for mild steel and the optimum speed is found through trial and error. Also, each drill should have enough power to remove the quantity of metal desired and the drill bit should never slip in the drill chuck. Also, your drill bits must be sharp. They will no doubt get dull and need to be replaced or sharpened about every 200 holes if you are using a mag drill, and every 10-50 holes if you are drilling freehand. Do not sharpen your drills by hand. It takes special jigs/machines and skill to ensure that a drill (or centerless cutter) will be sharpened properly in order to work correctly. Do not buy cheap-o drills either, get them from a reputable stateside manufacturer.
Given that you essentailly have to start each hole four times to make one hole, it would help you greatly to buy center-cutting 1/4" drill bits. These have an extra grinder-cut on the end of the drill which makes the drill cut all of the way to the center of the hole. Regular drill bits have a bridge of metal across the tip. These are fine once you have the pilot hole drilled. Using a center-cutting drill for the first hole will make drilling that hole much faster and easier.
Proper technique is a must if you want to preserve your cutters. First, use coolant. This will keep everything from overheating and allow you to work faster. Get a good industrial cutting coolant, not a lubricant or oil. You should add this to the cutter and workpiece before starting a hole and continue to add coolant little by little as you make the cut. Always start the drill before you make contact with the work. When you make contact between the drill and the workpiece, do so lightly. Then, press the drill just hard enough to start the cut. As you cut, observe the color of the chips and the torque on the drill. If the chips are a blue color, then they are too hot. Feed the drill less. If the drill begins to bind in the hole as heat builds up, then feed the drill less or use more coolant. Additionally, you will probably have to clear the drill to prevent the flutes from clogging with curls of metal. To do this, let up on the drill pressure for an instant every 10-20 seconds. This will cause the curls to break, which will help them to travel up the flutes.
Another thing, be careful not to overheat your drill motor. Avoid using super-long and skinny extension cords. If the cooling air leaving the drill feels like it is about to scald your skin, then back-off on the drill pressure. Should the drill begin to smoke (you are burning insulation), keep the trigger pressed and remove the load. This will let the cooling fan do its job the most effectively and just may save your tool.
I hope this helps and sorry for the length.

Sincerely,
taylorcrafdt1947
Christopher J. Mikesell

[LawsonWeldingLLC]

left hand drill in a right hand brace ? lol couldnt help myself

[AJM]

Originally Posted by Jack Olsen

I think this is the key question, based on the progress you made:

What RPM is the drill you're using turning your bit at?

the drill doesnt have set speed , but we are running it pretty slow

Originally Posted by taylorcraft1947

AJM,

1.5 holes drilled in 4 hours? Drilling should not be that much work. Speaking from experience, it should take no more than 1 minute 30 seconds to drill a 1 inch hole through 3/8" structural steel using a good mag drill and a "centerless" cutter with coolant (I have done this 8 hours a day for weeks at a time). If one guy center-punches the holes as you go, you should be able to position and drill at least one hole every 3 minutes.
However, spindle speed, power, and proper technique are everything when it comes to drilling holes. This means that you need several drills and/or a variable speed drill if you are going to step drill the holes. A 1/4" drill should spin about 1500 rpm, a 1/2" drill should spin about 800 rpm, and a 1" drill should spin about 400 rpm. These speeds are approximate values for mild steel and the optimum speed is found through trial and error. Also, each drill should have enough power to remove the quantity of metal desired and the drill bit should never slip in the drill chuck. Also, your drill bits must be sharp. They will no doubt get dull and need to be replaced or sharpened about every 200 holes if you are using a mag drill, and every 10-50 holes if you are drilling freehand. Do not sharpen your drills by hand. It takes special jigs/machines and skill to ensure that a drill (or centerless cutter) will be sharpened properly in order to work correctly. Do not buy cheap-o drills either, get them from a reputable stateside manufacturer.
Given that you essentailly have to start each hole four times to make one hole, it would help you greatly to buy center-cutting 1/4" drill bits. These have an extra grinder-cut on the end of the drill which makes the drill cut all of the way to the center of the hole. Regular drill bits have a bridge of metal across the tip. These are fine once you have the pilot hole drilled. Using a center-cutting drill for the first hole will make drilling that hole much faster and easier.
Proper technique is a must if you want to preserve your cutters. First, use coolant. This will keep everything from overheating and allow you to work faster. Get a good industrial cutting coolant, not a lubricant or oil. You should add this to the cutter and workpiece before starting a hole and continue to add coolant little by little as you make the cut. Always start the drill before you make contact with the work. When you make contact between the drill and the workpiece, do so lightly. Then, press the drill just hard enough to start the cut. As you cut, observe the color of the chips and the torque on the drill. If the chips are a blue color, then they are too hot. Feed the drill less. If the drill begins to bind in the hole as heat builds up, then feed the drill less or use more coolant. Additionally, you will probably have to clear the drill to prevent the flutes from clogging with curls of metal. To do this, let up on the drill pressure for an instant every 10-20 seconds. This will cause the curls to break, which will help them to travel up the flutes.
Another thing, be careful not to overheat your drill motor. Avoid using super-long and skinny extension cords. If the cooling air leaving the drill feels like it is about to scald your skin, then back-off on the drill pressure. Should the drill begin to smoke (you are burning insulation), keep the trigger pressed and remove the load. This will let the cooling fan do its job the most effectively and just may save your tool.
I hope this helps and sorry for the length.

Sincerely,
taylorcrafdt1947
Christopher J. Mikesell

great post , thanks a lot , we are using lubricant and not coolant.. just using what they give us , i'll recommend coolant to the foreman ... also we only have a couple bits, we are sharpening them as we go.. basically after 5-6 holes we sharpen it using a grinder and we are going through a lot more holes per day now . We dont have a nice bit sharpener so we are just workign with what we've got .

[denrep]

Originally Posted by AJM

... just using what they give us

. . .We don't have a nice bit sharpener so we are just working with what we've got .

By not investing in the right tools for a job like this, with lost time, the company is paying over and over for the best equipment money could buy, they're just not getting it. Crazy, but oh well, it's their dime.

From what I can gather about the drilling, I second this suggestion:

Originally Posted by Pavinsteelman

Small frame drill from Jancy or Hougen with 1" x1" annular cutters.

Good Luck

[Fat Bastard]

Originally Posted by LawsonWeldingLLC

The problem with annular cutters u have to remove the slug before going on to the next hole, if there 12 guage and its all stacked upon each other i personally would run to the home depot or lowes and buy a 1inch punch for electrical work or a "stud punch" looks like bolt cutters with a punch in it i hate doing anything to galvanized that has anything to do with heat, my health is worth more than that to me.

WRONG! You are giving incomplete information.
see here

Cutters for Truck Frame Drilling
Truck frames are manufactured to retain extraordinary
strength and durability. Consequently, frame materials are
more difficult to drill. An effective way to combat this
problem is to use an ID-style cutter that is also TINI coated.
Combined, the resulting cutter simultaneously permits
continuous drilling through layers while enhancing cutting
performance and extending tool life. To order, add the
suffix “ID TN” after part number or set number.

[LawsonWeldingLLC]

Yeah if ya wanna go buy more cutters thats fine , im speaking in a since of going to fastenal and getting a annual cutter , they are tapered on the edge and u have to drill each sheet individually, how about we see a picture of what the guys actually drilling and perhaps instead of saying WRONG say there are other cutters a person could use that will allow you to drill through multiple layers...

[Fat Bastard]

You can take offence at my direct reply all you like it won't change the facts. Your comments were and are wrong. That you don't know what tooling is available is not my problem. That you have limited knowledge is not my problem.

Definitive, and declarative statements will usually create problems for the person making them.

Your misinformation declarative and my definitive have created this.

[LawsonWeldingLLC]

Thanks for bein a douche i appreciate it

[Fat Bastard]

Your welcome. Might be next time you check yourself likely not but either way I'll correct your errors when I see them.
Cheers.

[LawsonWeldingLLC]

I appreciate learning new things , Thanks, it doesnt bother me what happens on the internet - once the hood is down and the checks in my wallet i dont care.

[Sandy]

It should be the responsibility of supervision/management to do most of the thinking, planning and aquiring the right tooling for the job. Sure, the laborer and boss can work together to figure out what works best but when it comes down to the bottom line you do the best job you can with what you're handed.

Are these laying down on the table or standing up & in place out on the job? Drilling all the way through from one side or drilling from both sides? Tightly sandwiched material or loose layers or spaced layers? Big difference in methodology. A conventional 1 inch bit is about the last thing I'd want to use for anything less than about 1/4 inch material. Especially if it was with a hand drill. Instinctively I'd jump back about six foot if someone handed me a 1 inch bit and said go drill a bunch of holes in some loosely layered sheet metal with a hand drill. Not that it can't be done but it would be one biting, snagging, grabbing wrist breaking sumbeech.

If these two guys are making this conventional twist drill thing work out my hat is off to 'em.

[Jay O]

http://www.yankeereamer.com/products.asp

One drill bit I've used in the past was shaped like a reamer. I think that it went under the name or manufacture "Yankee". The first 3" were tapered and the last 3" were the actual dimension. The nice thing about them was that they would pull or feed themselves and made it easy to drill multiple holes. On a 1" bit you would have to drill a pilot hole and they are also kind of expensive.

[Fat Bastard]

Originally Posted by LawsonWeldingLLC

I appreciate learning new things , Thanks, it doesnt bother me what happens on the internet - once the hood is down and the checks in my wallet i dont care.

If any of this were true you would not have posted the following now would you.

"Thanks for bein a douche i appreciate it"

Thanks for being you.