Making holes in metal

[kbrothers]

Started cutting out pieces for my FEL and am thinking ahead to the holes for bolts and pins. I have a Delta drill press and a variety of drill bits up to 1" which should be the largest hole I have to make in 1/4" steel My question is Is it better to drill a small pilot hole and gradually increase the bit size Or go strait to 1"? Buy a hole saw? And on another note my cut off saw has a 3/32" thick blade a lot Isee are 1/8" thick would it hurt to use one? I have weded in the past but haven't done the fabrication part Thanks for bearing with me Ken in Pa

[vince_o]

Ken

I dont know about the cut off saw part but I always start with a pilot hole and work up. I oil the work a good bit too, as not to over heat the drill bit. The bits I have have been real good so far in drilling steel and in some trannies at work.

maybe some of the metal working guys will chime in, I too am in the learning stage.

[albie]

Ken I agree with vince, start small and use plenty of oil. A nice slow speed on your drill press and steady pressure help alot too, seems bits work longer because hand drills tend to get sped up easily without realizing it.

[Paulf]

Ken, they're giving you good advice. Start small and work your way up. And, I assume when they're speaking of "oil" they're referring to cutting fluid. If you don't have some, it's worth the investment. You'll get a better hole and your bits will last a lot longer.

[Farmallgray]

Not just any oil will do. Be sure to use cutting oil. I personally like to use hole saws to do larger holes like that. However I have a big old antique drill press that can be slowed way down to run them without burning them up.

[mgonitzke]

I assume that bushings will be welded into those holes, and the actual pivot pins will be 3/4" or so?

[kbrothers]

Matt you are correct Thanks all I'll have to get cutting oil Vince how you making out with yours ? Ken in PA

[Tom Scott]

Ken - If you pick up a bit that is large enough to inspect the point, like a 1/2" bit or so, the "point" is really a line from one side to the other. The length of that line is the "point" where not much real cutting is going on.

So, you start with a small drill that has a very small "point", which is able to get through because the area that is cutting-challenged is so small. Once you have an initial pilot hole, things are much easier for you and your bits. Your pilot bit should always be larger than the "point" (length of the line) on the bit that will come next. Your pilot should not be too big, or the next drill up will cut too aggressively and grab in the hole.

It can help to work backwards in your head. If you want to end up with a 1" hole, guess at a pilot for that (let's say 1/2") and hold the butt of it up to the point of the 1" bit. The 1/2" is probably plenty enough larger than the non-cutting area of the 1" bit, but not so close in size as to cause overly aggressive cutting. Then choose a pilot for the 1/2"; and so on. How many steps you need depends on the material, and to some degree how thick it is. By the time you get into your third hole, you will have settled on what sizes you need. Your initial pilot hole size in steel will probably be something around 3/16"; small enough to cut well without a pilot, but large enough that it is not likely to break.

Regular motor oil is better than nothing, but cutting oil is better. I have been using Kroil lately for drilling and tapping and it has worked well. Most drill presses don't go as slow as you would like for steel, but just slow it down to the slowest speed, and it should be ok.

[klinej]

Hi Ken
When I started to build my loader I used the pilot hole then the 1" method until my neighbor said try his carbide tip hole saw all I can say is thats the way to go it cuts through 1/4" steel
like a hot knife through butter.The brand I used is champion they have a web site, I payed about $30. at a local tool store. Note if you go the hole saw route drill a pilot hole through both sides of the box tubing so the holes are aligned and you can flip the tubing and drill the other side with the hole saw use cutting oil . Have fun it was a great project . Do'nt forget the weight box / backhoe attachment

[Tom Scott]

I agree that a hole saw would be better for this. I just intended to explain how to size a pilot drill.

[vince_o]

ON one of the welding forums I read alot of guys are using the hole saw for trailer lights. This way you just push the rubber gromet in. I thought hole says were for plumbers and electracians.

Ken Im doing well. I got the eng wired up, need some fuel line, oil filter and a batt. Dang Ive got all that in stock, LMAO! I hope to have it all up and going by the end of feb.

I got my first real welding job sat. I got to build a hay manger for the preacher next door. So this will eat up a weekend or two.

[Jeff in Pa]

Regardless of whether you decide on drill bits or hole saws, correct rpm is extremely important to long tool life.

Check out this chart to see what surface footage the material you're cutting is to be used


Then look here to match diameter and surafce footage

[Farmallgray]

Vince,
We never had hole saws in the shop when I was growing up and learning. But we had a nice selection of drill bits up to about 2" or so, along with a drill press that could run them. I would borrow holes saws from my Dad when I needed to make a hole for a gauge or something but never for any serious fab work. Then I bought my own small set so that I wouldn't have to borrow from Dad.

Once I had them around I started to use them more and more. Again having a drill press that can be slowed way down really helps. I used them to make a lot of the bearing retainers and other parts for the rearends in my pullers. I would use the hole saw to rough out the hole then finish bore them on the lathe. I have cut holes through steel as thick as 1-1/4" with them. Takes a good bit of patients, lots of cutting oil, and to stop and blow out the chips with compressed air frequently.

[SWilliams]

I use a few things to get big holes in metal. Which one varies by the thickness of the steel. For a lot of stuff I use either good conventional bits or Irwin Uni-Bits. The step drills are nice for stuff up to 3/16" or so. The nice thing is that you don't bother with a pilot hole. Just punch the spot and start drilling till you hit the size you need. For things that will be welded in they also can chamfer the hole for better weld penetration. And because they self pilot and take small steps they work great in smaller drills.
For bigger holes I use either a hole saw or a plasma cutter.

[vince_o]

Todd

It goes back to that email a few weeks ago, Half Ass its not around you area. I agree with what you guys are saying, gota have the right tool for the job. Heck In all my dealings with heavy equipment, and trucking, Ive seen all these guys using Snap on tools, I thought Id never be able to aford them. Now every week I add more to my box, and a good tool makes the job easyer or faster, with out loosing quality!

My little drill press wont turn slow enough to do real thick metal. I use oil cause I dont have cutting oil, but its better than nothing, and just go slow with my preasure. Id love to have a plasma cutter, but in time it will happen. Im really just starting to learn how the work this metal stuff. Its verry intresting learning how it bends with heat or shrinks / grows. As far as a lathe some day. When Dave K was here a few months ago we talked about me getting one. So when the time comes I will call on him to find me one.

I really enjoy watching the projects you guys do and really you all have set a chalange in me to be ablel to do this. This loader is a big to do for me, even if it was half built. My biggest chalange will be the tractor seeing it was under water. I may fire this eng up and find its bad and have to put a differant one on. I have another one sitting on the shelf that needs an oil seal. I was told it was good but how good, it too may be a smoker

BB told me that I should put the bota eng in the 1872, but I have no come to gripps yet to cutting up a good tractor, thats not a QL!

[wdeturck]

I was using a spray can of a product like this one for years that I got from a buddy of mine. It was great for SS and tapping and wasn't as messy as cutting oil. I want to get a can of it next time I order something from McMasters. I lost my last 3 cans in the fire. I've been using PB Blaster that works for keeping the bit cool but te stuff I had was better.
http://www.mcmaster.com/#tap-magic-cutt ... ds/=fceewh

[SWilliams]

Vince, Watch out for that Snap-On guy, My local one acts suspiciously like a certain fallen angel who is willing to accept souls for payment!!!
I have done a lot of stuff using "adaptive tooling" and have been spoiled in recent years by acquiring some of the tools that make life easier.
I would try a set of step bits in that drill press, you will be surprised how well they let you do more because of the small amount that they take at a time.
One thing I did with a small press I had was to buy a different pulley stack for it.

[vince_o]

Steve

Oh my guy had a REALLY nice deal on a box that I would have loved to had. I just couldnt do it. 3 yrs of payments, just not now. I try to get one thing at a time and pay him no more than 3 payment to pay it off. I piced up a nice 3/8 impact the other day, Ill be dragging the payment plan out a little longer than I like. Theres something about their ratchets and sccrew drives that I really like. The screw drivers are great on the carbs, hardly ever do you strip out a screw.


I like the fallen angle coment

[albie]

Vince I have been working on cars for 29 years and dont think I have been without a tool payment but very few times and of all the dealers I have purchased from(MAC Matco Cornwell) Snap on has the best product. Their sockets,ratchets, and screwdrivers are second to none, and their tools boxes are about the best too and I've owned them all at one time or another.

[bruce s]

Ken there is a lot of good advise here, just one more thing . Be sure to clamp things down or use a good vise on your drill press. A piece of steel with sharp edges sping at 500 RPM can ruin your day .

[BigMike]

Ken,you might find someone close to you that would help with machining you may not be set up for,
http://bbs.homeshopmachinist.net/

A lot of these guys are very helpful.I would be glad to help if you have something that can be shipped back and forth.