Square hole

cool hand · Aug 30, 2016

Is there a practicable way of making a square hole, such as to accommodate a carriage bolt, in 1/4" or lighter steel? Something that this octogenarian mind has not yet been able to imagine?

TimV · Aug 30, 2016

File it. Drill to clear the bolt diameter and clean out the corners with a square or triangular file--provide you don't have dozens to do, it goes much quicker than you'd expect.

Russ from MN · Aug 30, 2016

Like Tim says, file them. I have some coarse square files that do it quickly, they can be tapered a little to match the bolt, and don't go too big.

Bob Harvey · Aug 30, 2016

If it is light /sheet metal, just give the carriage bolt a stout whack with a sFH, and that should do the job - self fitting. HTH

Steve in VA · Aug 30, 2016

Had to do several helping on streetcar repairs. I made a square block out of brass and used the welder to build up around it. Knocked brass out and went to the next one. Of course, there were a lot and they were pretty stout so this might not suit your needs.

ss55 · Aug 30, 2016

There are many way to make a square hole in thin steel:
punch
broach
gas torch
wire EDM
EDM
water jet
laser cutter
are a few of the processes used in manufacturing.

For a small shop a file, die grinder or a Dremel tool might be the easiest.

gene bender · Aug 30, 2016

Drill the hole for the body then a triangle file will be OK

jeffcat · Aug 30, 2016

Another way is when you use the triangle file and are almost there. If you can, use heat on the item, heat it a bit and then drive the carriage bolt in or zap it with an air wrench. Makes it's own square hole. Triangle , or square file is the only thing that will give you a pretty square hole by hand.

Stephen Newell · Aug 30, 2016

How many do you need? Some metal working shops have a hydraulic press that would just stamp the holes easy.

da.bees · Aug 30, 2016

Burn out a hole then drive in a square punch while hole is hot. Burn hole,drop cariage bolt in and hit it with hammer to slightly weld bolt
in hole.

billmart · Aug 30, 2016

Google greenlee knockout punch. they are made for making square holes in sheet metal

mjsnodgrass · Aug 30, 2016

I was making a boring bar once. had a piece of TGP 2" shaft in drill press drilling 17/32 hole when hot shot engineer came by. asked what I was doing. told him I was drilling a square hole. he looked at me kinda funny, and said he wanted to see the square hole when he came back through the shop. after he left I pushed a 1/2" square broach through the hole and put the shaft back on the drill press. you should of seen the look on his face. 8 years of college, and nobody told him about square holes.

Dr. Walt · Aug 30, 2016

Either make a Broach for the size you need, or take your sheetmetal to a Metal Shop that has square punches & dies for their Iron Worker.

DLMKA · Aug 30, 2016

Reminds me of something that happened in my high school machine shop class. We had one kid that was a few bricks shy of a load. Nice guy, just dumb as a sack of hammers. He was making a flat blade screwdriver for his project. Made it out of hex bar stock and was machined and top heat treated. Handles were polycarbonate stock. Came by where I was working and asked me how to get the hexagon bar into the handle. Being a little ornery I told him to go ask Mr. McConnell for the hexagon drill bits that he keeps in the supply closet. Off he goes, all the way into the classroom, stops dead in his tracks right McConnell's desk, pauses, and marches right back out to me mad as an old red hen. I have no idea what he said because I was laughing so hard. About 10 minutes later teacher comes out and asked what Ferguson went in the classroom for and walked out without saying a word. Told him the story and it was all he could do to keep from laughing.

big jt · Aug 31, 2016

Ag Leader seems to have a source on square files. With every install kit I have gotten from them there was a square file for just this purpose for use on the clean grain elevator.

Of just search google.

JT
Google square file search

JK2 · Aug 31, 2016

For small diameter holes you can use a square broach in a press to make a round hole square. Visit this site to see some examples:

http://dumont.com/our-broaches/square-broaches/

I have a device that holds a 3 cornered rotary cutter vertical in the drill press while allowing it to move off center and cut the corners out on larger holes by following a pattern that is clamped to the piece that you are putting the hole in. It will also make a hex hole with a 5 sided cutter.

Adirondack case guy · Aug 31, 2016

Take a small 3 sided file and file your holes square.
Loren

JML755 · Aug 31, 2016

(quoted from post at 19:06:07 08/30/16) Is there a practicable way of making a square hole, such as to accommodate a carriage bolt, in 1/4" or lighter steel? Something that this octogenarian mind has not yet been able to imagine?

https://www.youtube.com/watch?v=ALiqAXiTQBg

Square hole

cool hand

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TimV

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Russ from MN

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Bob Harvey

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Steve in VA

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ss55

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gene bender

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jeffcat

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Stephen Newell

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da.bees

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billmart

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mjsnodgrass

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Dr. Walt

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DLMKA

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big jt

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JK2

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Adirondack case guy

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JML755

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