Square holes for carrage head bolts?

Any tips to making square holes for carrage head bolts in 1/8th steel? I have thought of sevral things but nothing easy R). I could do it with the plasma cutter which I think is my best bet . Or I could drill and file. Or I could really cheap out and drill a over sized hole and spot weld the bolts from the back side since I have no reason to remove them from the piece.What do yall think?

 

I drill the hole for the bolt size, than a small flat file to square it off to fit.
My .02

 

:iagree: Most nibbler tools I've seen only go to 18 gauge. Never saw one that would do 1/8", Which is between 11 gauge and 10 gauge. Not saying they don't exist, just never heard of one.

tommy b

 

take by a metal fab shop see if they can punch them for you.

 

Drill and file is the cheapest. If you've got lots of them to make, you could buy a broach. I think you drill a hole first, then press the broach through to make the hole square. This is the big $$$ way.

 

I have drilled the hole to size, heated The piece and used a square tapered punch like a square easy out to square the hole for a 1/8 plate a mild steel punch would probably do or an old carrage bolt. Have also used carriage bolt and washer two sizes larger and a nut to draw the bolt through the hole. once it cools the hole shape is permanant.

 

x2 like Johnnie said. Blacksmith it.

Pete

 

I bought a small square file. Worked really good. I used it when I put more factory nut plates in the firewall when I made the cover for the distributor.

http://groups.msn.com/ScottShannonMilliner/sm465coverplate.msnw?action=ShowPhoto&PhotoID=166

 

How about a die grinder with a carbide bit.They make both air and electric models.It will open those holes up fast.Buy some ear plugs it will be loud.

 

Believe it or not they MAKE drill bit that drill square holes.. Home Depot ,Lowes have them $$$ all it is is a regular drill bit with a square tubing around them but hardned.. kind of like a hole saw !!! Use a bit smaller and pull the carraige bolt down as you tightnen hit the top with a hammer to help it along..

 

Square broach is the way to go if you will be doing this a lot. You will get consistently sized holes that are square and won't get the "Popeye" effect from all that filling. Ain't cheep though.....

http://www.jlindustrial.com/endeca/...quare+broach&go.x=0&go.y=0&Ntk=Keyword+Search

You may also do a search for an air powered filer, although that is likely to be pricey as well.

A third option is to drill the holes where you want them and pay a machine shop to broach them for you. Or see if you can "rent" one of their old used up broaches....

 

Thinks for the tips yall , Im going have to do some hands one research on some scrap steel.Ill report back after the weekend on what happens.

 

quick update I just made me a cheap broach with a piece of 3/8th key stock

 

:uwop:

 

No camrea here but all i did is get a 12" piece of key stock ,rounded of one end with the grinder and slowly took less and less off till I got back to 100% square. I just hope its hard enuff , which it shouldnt take much if I drill a 3/8th hole then heat the metal before driving the home made broach threw. I only have to do it for 8 holes.

 

What are you using to back up the metal (on the side away from the one you are starting the broach through)?

tommy b

 

I have a anvil but I was thinking about doing it on top of my big vice.

 

Here you go david , I might get to try it tommrow.

 

I know you said you had eight holes to do and that four times as many as I just completed. I used a very small flat file that I picked up at Radio Shack in an electrical file kit. Worked great for squaring up 9/16" holes in a Jeep floorpan (mounting a console using carriage bolts from the bottom up).......Good luck with your project !!