Thread: Big Holes in Thick Plate?

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I need a 2 1/2 inch hole in a 1/4 inch thick plate (steel). I am trying to avoid paying a bunch of money for a hole saw that may or may not make it through the plate without dulling or going to the waterjet guy.

Any suggestions? I am seriously thinking about drilling about 50 1/8 inch holes in a circle and then filling down the rough spots. harbor Freight is having a sale on 1/8 inch drill bits.

Thank you

Got a hand-held jigsaw and a 3/8 drill bit?

Use the hole saw--that's what they are designed for and work better than anything else

You will need a drill press or 1/2 drill to have enough power to pull it and lift the saw to blow the chips away often as in material that thick they will be trapped in the teeth---cutting oil helps too

Jerry

Buy a bimetal tooth holesaw---thats what they are designed for --use a drill press if you can or a 1/2 drill motor--cutting oil and blow the chips out often

Jerry

4 steel cutting blades and a jig saw and some oil, go slow and it will cut the hole

Just buy a hole saw. Milwaukee's are good, if used at low speed with plenty of oil in a drill press they'll last a long time. Tools are an investment, not an expense.....

Ask Santa for a set of them for Christmas---you'll use them a lot around car building--the bigger ones have got to be run slow to keep speed down

Jerry

You can use a plasma cutter if you or a friend have one. Make a template with 1/4" plywood .

...yeah, every time I try to save money by not buying the right tool it costs me in the long run. I save money by buying an incorrect tool but then I end up spending more when I STILL have to buy the correct tool. Or I ruin the part..... Just buy a hole saw. "buy once, cry once".... Bill

Yep, holesaw, and 1/4 isn't all that thick. First drill a pilot hole like 3/16. then run the 1/4 inch holesaw pilot drill into that hole and start cutting. I use water and soap for lube, but many use cutting oil. I just don't like oil on parts I am going to paint later. By starting with a smaller hole than the 1/4 inch one you get a truer cut as it won't wobble when the hole saw starts to cut. Home Depot and Lowes even carry good ones like Rigid.

BTW, CLAMP DOWN THE PIECE YOU ARE CUTTING. I recently wrapped my arm around the drill press when the holesaw grabbed the piece and spun it and me around the arbor. They give you NO WARNING.

Don

Let's see, hmmmmmm. some C-4 and det chord

Troglodyte and bigtruck guy are more my thinking. I would definitely use the plasma cutter before messing with the hole saw,if you have access to one. you can make a guide to make the circle perfect, if you are willing to drill 50 1/8' holes and clean up with a file it sounds like maybe it doesn't need ot be perfect, in that case you could freehand the cut (draw a circle and trace it with the plasma cutter without using a guide) and get pretty close. I have done that. I love the plasma cutter.

if you can get c-4 and det cord why waste time working on hotrods!! seriously, blowing stuff up has got to be one of the funnest jobs on the planet.

Oh, and if you use the plasma cutter you don't need a pilot hole. put the tip inside the circle facing to the side and tip it over slow, it will cut in and then you can run it to the edge of the circle and start your cut (I hope I explained that right).

Red

I appreciate the help. I broke down and bought the hole saw kit at Harbor Freight on my way in this morning. It was closer to $40 but significantly cheaper than a waterjet guy and certainly less frustrating than drilling 50 holes.

I wish I had a plasma cutter, I might never leave the house again if I did.

I am still a relatively young guy and don't have many friends in the hot rod hobby who build their own stuff. Therefore I am on my own. I will just keep buying new tools until I have everything I need.

Thanks again!

You know what caddy, I am a young guy (i guess not that young any more, since hitting 30) that just happens to be fortunate enough to have a cool uncle that buys or has every thing we need. Problem I have is I don't have any friends that enjoy cars at all. just me and my uncle. that sucks. I get excited and tell friends about it and they stare at me like I'm talking chinese.

Red

I am very fortunate to have a number of interested friends, but none with cars or that know the right end of a screwdriver to use. That is part of the reason for building the family hot rod. Not only can I take my wife and young sone to shows and such, but now I can pick up some friends and introduce them to some of the great car shows we have out here in AZ.